CN117580496A

CN117580496A - Video processing device with noise effect mitigation

Info

Publication number: CN117580496A
Application number: CN202280045559.9A
Authority: CN
Inventors: 让-弗朗索瓦·雅克·安德烈·帕卡尔; 斯坦·卡尔森; 约尔根·莱因霍尔德·奥尔森; 托比亚斯·迈克尔·奥斯特格伦
Original assignee: Ambu AS
Current assignee: Ambu AS
Priority date: 2021-06-30
Filing date: 2022-06-29
Publication date: 2024-02-20
Also published as: DE102021116905A1

Abstract

A visualization system, comprising: an endoscope (2), a display unit (18) and a communication bus (48); the endoscope (2) comprises: a proximal endoscope handle or interface (4) comprising a handle or interface housing (38) and a handle or interface printed circuit board (40) housed inside the handle or interface housing (38); and an insertion cord (6) extending from the endoscope handle or interface (4) and comprising an insertion tube (8), a bending section (10) and a distal end unit (12), wherein the distal end unit (12) comprises a camera module (13) comprising an image sensor (14) configured to capture images and an image sensor circuitry (42) configured to communicate with the display unit (18) via the communication bus (48); the display unit (18) includes input circuitry (50) configured to communicate with the handle or interface printed circuit board (40) and the image sensor circuitry (42) via the communication bus (48); and the communication bus (48) connects the endoscope (2) with the display unit (18) and is configured to enable communication between the image sensor circuitry (42), the handle or interface printed circuit board (40) and the input circuitry (50); wherein the input circuitry (50) of the display unit (18) is configured to check, preferably continuously or pulsed, for high frequency noise and electrical disturbances on the communication bus (48).

Description

Video processing device with noise effect mitigation

Cross Reference to Related Applications

The present application claims priority and benefit from german patent application nos. DE102021116905.4 and DE102021116927.5, filed on 6 months and 30 days 2021, which are incorporated herein by reference in their entirety.

Technical Field

The present disclosure relates to a video processing device operable to mitigate signal noise effects in an endoscope communicatively connected to the video processing device. The present disclosure also relates to an endoscope having a sensor operable to detect signal noise.

Background

In general, endoscopes and in particular, surgical specialized endoscopes (such as bronchoscopes, arthroscopes, colonoscopes, laparoscopes, gastroscopes, and duodenums) are well known in the art and are used for at least visual inspection and diagnosis of hollow organs and body cavities, and optionally for assisting surgery, for example for target tissue sampling. Both reusable and disposable endoscopes are known in the art. Basically, an insertion cord comprising an insertion tube, (distal) bending section and (distal) end unit extending in sequence from a proximal endoscope handle can be inserted into a hollow organ or body cavity to be endoscopically examined. The terminal unit comprises a camera module arranged to convert the optical image into image data which is passed to the video processing device for presentation by means of a display connected to the video processing device.

It is known that endoscopes generally include an internal working channel disposed within an insertion cord that extends from an endoscope handle toward a distal tip unit and has an opening at a distal end of the distal tip unit. The working channel is typically accessible via an access port provided in the endoscope handle. The surgical instrument may be guided through the working channel into a body cavity of the patient via the access port (i.e., distally relative to the distal end of the endoscope). An operator may perform a medical procedure within a body cavity of a patient using a surgical instrument. It is known in this context to use electrosurgical tools in endoscopic surgery, i.e. to insert electrosurgical tools into a body cavity of a patient via an access port and a working channel. Additionally, the working channel may also be used as an aspiration channel to withdraw, for example, bodily fluids from a surgical field within the patient's body.

Known electrosurgical tools operate with high voltage pulses (e.g., in the range of 4kV to 5 kV) and may generate high frequency noise and electrical interference. An electrosurgical tool configured to perform Argon Plasma Coagulation (APC) is an example of such an electrosurgical tool. Argon plasma coagulation is an electrosurgical monopolar procedure that uses ionized argon, which can be easily ionized as an inert gas, to perform epidermal hemostasis, inactivation, and ablation. The high voltage pulses cause a strong electric field (high frequency) that may be manifested as high frequency noise and electrical interference on the cable located near the electrosurgical tool. A cable or wire is disposed in the endoscope to communicate images from the camera module to the video processing device and to communicate commands or configuration parameters from the video processing device to the camera module. High frequency noise and electrical interference may be present along the entire working channel.

It is known to use such electrosurgical tools in combination with well known reusable endoscopes. In reusable endoscopes, many of the components are made of metal parts and cables for transmitting images from the distal tip to the handle (which cables are disposed within the insertion cord of the endoscope) can be shielded so that the reusable endoscope provides good shielding from high frequency noise and electrical interference that may be generated by the use of such electrosurgical tools.

For disposable endoscopes, it is important that the entire endoscope can be manufactured economically and inexpensively. Accordingly, the parts/components of the disposable endoscope are mainly made of polymeric materials to enhance disposability, reduce the size (e.g., cross section) of the insertion cord, and reduce costs. In disposable endoscopes, the working channel is typically formed as a flexible polymer tube. Further, for disposable endoscopes, it is desirable to use unshielded cables that are less expensive than shielded cables. Thus, disposable endoscopes typically do not provide good shielding from high frequency noise and electrical interference when inserting and manipulating electrosurgical tools in a working channel. However, disposable endoscopes should also be suitable for use with electrosurgical tools. Accordingly, communication between the video processing device and the camera module should be protected to minimize signal noise effects caused by the use of electrosurgical tools.

More specifically, at the distal end unit of the endoscope (both disposable and reusable), there is an image capturing device, such as a camera module, comprising an image sensor and image sensor circuitry. The image captured by the image sensor may be shown on a monitor/display screen communicatively connected to the endoscope. As described below, the video processing device may include a display (in which case it may be referred to as a "display unit"), or be communicatively connected to a display. The video processing apparatus may further include an image processing device like a CPU or FPGA, which may communicate with the image sensor via a communication bus. In particular, images captured by the image sensor may be transferred via the communication bus to an image processing device where the images are processed. Further, settings may be transferred from the image processing device to a camera module disposed in the distal tip via a communication bus. For disposable endoscopes, the cables or communication bus conductors for the communication bus are generally not shielded. However, the possibility of shielding the communication bus is not excluded.

When a high frequency electrosurgical tool, such as an electrosurgical tool configured to perform argon plasma coagulation, is inserted into the working channel of an endoscope and operated by an operator, the high frequency voltage of the high frequency electrosurgical tool may generate noise in the communication bus. Noise may lead to erroneous locations in the registers of the camera module or erroneous bit insertions with erroneous values, for example, and bit losses of data transmitted via the communication bus during data transmission, since the communication bus may be arranged quite close to the working channel and thus to high frequency electrical noise sources (electrosurgical tools). The high frequency noise may cause flickering and frozen images to be displayed on the display screen. This problem may be exacerbated in disposable endoscopes, and particularly without shielding the communication bus cable. Further, when high frequency noise occurs in the set signal, particularly in the register address, data may be written in an unknown address, i.e., in an unexpected random position, and this may cause interruption of normal operation, and a complete reset of the entire system may be required to resume correct operation. Thus, high frequency noise may greatly affect the endoscope operation performance, and the high frequency noise may cause an operator to fail to perform an endoscopic operation as intended. The term "cable" as used herein refers to a wire used to establish a communication bus. In a serial communication bus, a cable may include one, two, or more conductors, for example, a conductor for a data line and a conductor for a clock line. Additional wires are provided in the endoscope to supply power and ground to the camera module and the illumination device. In a parallel communication bus, the cable includes a plurality of conductors, for example four or more conductors, based on the data width of the bus.

In summary, when a high frequency electrosurgical tool is used with a disposable endoscope, the communication bus between the endoscope and the video processing device is quite susceptible to high frequency noise caused by the use of such electrosurgical tools. In particular, there is a risk of losing real-time images for various reasons, including "freezing" (requiring a reset) of the camera module, and due to communication errors on the communication bus, i.e. data writing error locations or error data being written into registers of the camera module in the far-end terminal.

Disclosure of Invention

It is an object and object of the present disclosure to obviate or at least mitigate the disadvantages of the prior art and to suitably address the above described situation. In particular, flickering and freezing of images and interruption/system malfunction of normal operation due to high frequency noise and electrical interference on a display screen connected to an endoscope should be prevented.

The task and objects of the present disclosure are solved by a visualization (endoscope) system according to claim 1, by a method according to claim 17 and by an endoscope according to claim 18. Advantageous embodiments are claimed in the dependent claims and/or explained below.

In the present disclosure, "distal" means in a direction facing away from the operator, preferably toward the patient, and "proximal" means in a direction facing toward the operator, preferably away from the patient.

The present disclosure relates to an (endoscopic) system comprising: an endoscope or endoscope unit, a display or display unit and a communication bus, preferably a serial communication bus; an endoscope includes: a proximal endoscope handle or (robotic) interface (as defined above) comprising a handle/interface housing and a handle/interface printed circuit board housed inside the handle/interface housing; and an insertion cord (endoscope shaft) extending from the endoscope handle/interface and comprising an insertion tube, (actively actuatable) bending section and a distal tip unit (endoscope head), wherein the distal tip unit comprises a camera module comprising an image sensor configured to capture images and image sensor circuitry configured to communicate with the display unit via a communication bus; the display unit comprises input circuitry (including in particular logic circuitry) configured to communicate with the handle/interface printed circuit board and the image sensor circuitry via a communication bus; and the communication bus connects the endoscope with the display unit and is configured to enable communication between the image sensor circuitry, the handle/interface printed circuit board, and the input circuitry; wherein the display unit/input circuitry of the display unit is configured to check, preferably continuously or pulsed, for high frequency noise and electrical disturbances on the communication bus.

Furthermore, the present disclosure relates to a display unit comprising input circuitry configured to check, preferably continuously or pulsed, for high frequency noise and electrical interference on a communication bus via which the display unit is connectable to an endoscope/endoscope unit and which enables communication between the input circuitry and the endoscope.

Further, the present disclosure relates to a method of checking, preferably continuously or pulsed, for high frequency noise and electrical interference on a communication bus via which a display unit can be connected to an endoscope/endoscope unit and which enables communication between the display unit and the endoscope.

In accordance with the present disclosure, a (separate) display unit is provided, which is particularly adapted to prevent high frequency electrical noise and interference effects that may occur when using, for example, an electrosurgical tool within a working channel of an endoscope, a communication bus configured to provide communication between the endoscope and the display unit. The present disclosure takes into account flickering and frozen images on a screen connected to an endoscope, or in the worst case, system failure may occur immediately/directly when high frequency noise and electrical interference occur in the endoscope. Accordingly, the display unit of the present disclosure, and in particular the input circuitry of the display unit, is configured to check, preferably continuously (i.e. continuously/uninterruptedly), whether high frequency noise and electrical interference is present on the communication bus.

If/if it is determined by the input circuitry of the display unit that there is high frequency noise and electrical interference on the communication bus that is particularly suitable (with respect to its quality and/or quantity) for affecting/communicating via the communication bus, the input circuitry may be configured to (temporarily) terminate the communicating via the communication bus.

The input circuitry may be configured to terminate communication via/through the communication bus for at least a specific, preferably predetermined, period of time in the presence of high frequency noise and electrical interference on the communication bus.

By terminating communication via the communication bus for a certain period of time immediately when there is high-frequency noise and electrical interference in the endoscope that are suitable for affecting the communication bus, it is preferable to avoid communication via the communication bus from entering a failure state in which, for example, images cannot be processed by an image processing apparatus provided in a display unit and thus cannot be displayed on a display.

Preferably, the communication bus is a serial communication bus like an I2C bus or an SCCB (serial camera control bus).

The endoscope may include a working channel configured for insertion of an electrosurgical tool (i.e., the electrosurgical tool may be inserted into the working channel). The working channel may extend inside the endoscope handle and/or inside the insertion cord, in particular from a working channel access port, preferably provided in the endoscope handle, to the distal end unit. In particular, the working channel is formed by a tip housing comprising a connector portion of the working channel access port (Y-connector), a (flexible) working channel tube inserted into the cord and a distal tip unit. The connector portion and working channel tube are typically made of a polymer/resin/plastic material. Preferably, if a certain quality and/or amount of high frequency noise and electrical interference is present in the working channel, the communication via the communication bus is terminated.

The preferred embodiment is characterized in that: the endoscope includes detector circuitry/protection circuitry/noise detection circuitry configured to detect high frequency noise and electrical interference in the working channel, particularly caused by the use and operation of the electrosurgical tool. That is, the endoscope itself is preferably configured to detect the presence of high frequency noise and electrical interference. Advantageously, high frequency noise and electrical interference are detected directly and immediately where they occur (i.e., in an endoscope). The detector circuit/protection circuit may be configured to constantly or pulsed look for high frequency noise and electrical interference that may affect the communication bus, and may be incorporated/implemented at least in part in the handle/interface printed circuit board.

The detector circuit/protection circuit may be configured to provide an output signal indicative of the presence of high frequency noise and electrical interference on the communication bus, especially if the high frequency noise and electrical interference reach a certain quality and/or quantity. It is particularly preferred that the output signal can be transmitted to the input circuitry of the display unit. If such high frequency noise and electrical interference is detected by the protection circuit/detector circuit and the input circuitry receives the output signal, the communication via the communication bus is preferably stopped by the display unit (its input circuitry).

It should be appreciated that the output signal may be transmitted directly to the display unit or may be transmitted indirectly to the display unit. For example, the output signal may also be a trigger signal that may pull down a connection/communication line (e.g., clock line) in a communication bus that transmits the captured image from the image sensor to the display unit. Stated another way, and more generally, the handle/interface printed circuit board (preferably in which the detector circuitry is at least partially integrated) may be configured to pull down an already existing bus (e.g., a communication bus that transmits captured images from the image sensor to the display unit) in order to provide a signal to the display unit indicating that there is preferably a particular quality and/or amount of high frequency noise and electrical interference in the endoscope. Thus, advantageously, no additional wires are required between the handle/interface printed circuit board and the display unit.

Preferably, the communication between the input circuitry, the handle/interface printed circuit board and the image sensor circuitry is based on a master-slave, wherein the input circuitry is a master device and the handle/interface printed circuit board and the image sensor circuitry are slave devices. This may be particularly advantageous in alternative embodiments where no detector circuit is provided in the endoscope.

According to the alternative embodiment, the input circuitry may be configured to initially set a communication line output signal of a communication line of the communication bus and compare the communication line output signal with a communication line input signal of the communication line received from the handle/interface printed circuit board to determine that there is high frequency noise and electrical interference (of a certain quality and/or quantity) on the communication bus.

It is particularly preferred that the communication line output signal is an output clock signal of a clock line of the communication bus and the communication line input signal is an input clock signal of the clock line of the communication bus, and the input circuitry is configured to initially set the output clock signal and compare the output clock signal with the input clock signal received from the handle/interface printed circuit board to determine the presence of high frequency noise and electrical interference on the communication bus.

Further, the input circuitry may be configured to generate a comparison signal based on a comparison of the communication line output signal and the communication line input signal, and determine that high frequency noise and electrical interference are present if the comparison signal exceeds a predetermined threshold.

In summary, according to alternative embodiments, the logic circuitry of the input circuitry may be configured to compare the output of a communication line, in particular a clock line, of a communication bus on the input circuitry with the input of a communication line, in particular a clock line, from a communication bus of the (handle/interface) printed circuit board. By comparing the output of the communication line of the communication bus on the input circuitry with the input of the communication line from the communication bus of the (handle/interface) printed circuit board, it is possible to determine whether high frequency noise and electrical interference is present on the communication bus without having to provide a detector circuit. The communication bus between the display unit, the handle/interface PCB and the camera module in the distal end unit is preferably master-slave based. The input circuitry provided in the display unit may be a master device and may pull down or raise a communication line on the communication bus. If the communication line is pulled low by the display unit but suddenly in an unexpected high state, the display unit may consider it to be present on the communication bus as high frequency noise and electrical interference. A comparison signal indicating the result of the comparison may be generated by the display unit. In the case where the comparison signal exceeds a predetermined threshold, high-frequency noise and electrical interference may be regarded as being present in the endoscope.

The display unit is thus preferably configured to check, preferably continuously, whether a noise detection signal (output signal of the detector circuit or comparison signal of the input circuitry) is received, which noise detection signal indicates that there is preferably a certain quality and/or amount of high frequency noise and electrical interference on the communication bus. When such a noise detection signal is received, the display unit, in particular the input circuitry, preferably performs a (termination) algorithm/method configured to terminate/stop the communication between the display unit and the endoscope via the communication bus.

According to a preferred embodiment, the logic (included in the input circuitry of the display unit) comprises a Field Programmable Gate Array (FPGA), and the algorithms/methods of the present disclosure are implemented on the field programmable gate array. Stated another way, it may be feasible to implement an algorithm/method on such a field programmable gate array forming part of the logic (circuitry) of the input circuitry provided in the display unit. Advantageously, field programmable gate arrays can be readily updated and programmed to perform the algorithms of the present disclosure.

According to a particularly preferred embodiment, the algorithm/method of the present disclosure comprises the following steps (i.e. the display unit is configured to perform the following steps):

a) Determining whether a noise detection signal is received;

b) Blocking the communication bus in case of receiving the noise detection signal;

c) Searching for another noise detection signal within a first predetermined period of time;

d) Restarting the operation of the communication bus in case no further noise detection signal is received in step c);

e) In case a further noise detection signal is received in step c), waiting until no noise detection signal is received within a first predetermined period of time, i.e. until the pulse burst transmitted by the electrosurgical tool has ended;

f) At the end of the pulse burst, waiting a second predetermined period of time and determining whether another pulse burst is detected during the second predetermined period of time;

g) Restarting operation of the communication bus in case no further burst of pulses is detected in step f); and

h) In case a further burst of pulses is detected in step f), step e) is repeated until no further burst of pulses is detected in step f).

More generally, algorithms/methods according to the present disclosure specifically consider the nature of electrosurgical units/electrosurgical tools used in endoscopic procedures. In particular, an electrosurgical tool configured to perform Argon Plasma Coagulation (APC) may be a specific example of such an electrosurgical tool. It has been found in accordance with the present disclosure that when such electrosurgical tools are controlled/powered, a specific noise signal is emitted. In particular, it is apparent that such electrosurgical tools periodically emit bursts of pulses in both a fast pulse mode and a slow pulse mode. The burst of pulses typically includes a plurality of individual pulses that may cause interference to the communication bus, which results in erroneous data being transferred to the erroneous address.

Advantageously, according to steps a) and b) above, the display unit is configured to stop/block communication on the communication bus immediately upon receipt of the noise detection signal/independent pulse, in order to prevent the independent pulse from causing interference to the communication bus.

Furthermore, according to the above steps c), d) and e), the display unit is advantageously configured to check whether the received noise detection signal is random noise (as is the case if no further noise is received during the first predetermined period of time, refer to steps c) and d)) or whether the received noise detection signal is part of a pulse burst (as is the case if a further noise is received during the first predetermined period of time, refer to steps c) and e)). If the noise detection signal is random noise, operation of the communication bus may be resumed/continued. The operation of the communication bus is continued to be prevented only if the noise detection signal is part of a burst of pulses.

The first predetermined period of time is preferably set dependent on the distance between two independent pulses in a pulse burst. It has been found that, for example, two independent pulses in a burst of pulses are typically spaced apart in the microsecond range. In this connection, the first predetermined period of time may be set such that it is sufficiently longer than the distance of the two independent pulses. Preferably, the first predetermined period of time may be set within a single digit microsecond range (e.g., between 1ms and 10 ms). According to the present disclosure, it is particularly preferred that the first predetermined period of time is set to 1ms. Setting the first predetermined time in this way makes it possible to reliably detect bursts of pulses suitable for interfering with communications via the communication bus.

According to step e) above, the display unit is preferably configured to wait in case a pulse burst has been detected until no further noise detection signal has been received within a first predetermined period of time. The display unit is therefore preferably configured to determine whether the end of the pulse burst has been reached.

By waiting a second predetermined period of time according to step f), it can be determined whether the first detected pulse burst is part of the pulsed operation of the electrosurgical tool and whether the distance between the two pulse bursts is too small in order to restart operation of the communication bus between the two pulse bursts. In particular, in the fast pulse mode of the electrosurgical tool, the operation of the communication bus is preferably not started between two pulse bursts.

It has been found that the second predetermined period of time is preferably set in the microsecond range, in particular between 100ms and 200ms (e.g. 125 ms). This makes it possible that another burst of pulses in the fast pulse mode of the electrosurgical tool will be detected, so that the operation of the communication bus can be prevented from being restarted in the fast pulse mode.

Preferably, in case another pulse burst/other pulse burst is detected within the second predetermined period of time, the display unit is configured to wait until no further pulse burst is detected within/during the second predetermined period of time. The display unit therefore preferably ensures that the communication bus is restarted only if the fast pulse mode of the electrosurgical tool has ended.

In a broad sense, the second predetermined period of time is preferably longer than the first predetermined period of time.

Further, it can be said that the display unit is configured to stop communication/operation of the communication bus for a first short predetermined period of time only in the case of random noise, and stop communication of the communication bus for a period of time longer than the first predetermined period of time in the case of a pulse burst caused by operation of the electrosurgical tool.

Further, it is apparent that a system according to the present disclosure may include an electrosurgical tool configured to be inserted into a working channel of a (disposable) endoscope and operated by an operator. During operation of the electrosurgical tool, the electrosurgical tool typically emits high frequency electrical noise, including bursts of pulses, at a wide range of frequencies. The display unit of the present disclosure is specially prepared for the case (electrosurgical tool inserted in the working channel of a disposable endoscope).

The display unit may comprise a display/screen/monitor. Alternatively, the display/screen/monitor may be in electrical communication with the display unit and formed/configured as a part/component separate from the display unit.

The present disclosure makes it possible to show real-time images on the display/screen/monitor during electrosurgery to maintain an acceptably low level of flicker during surgery. The solution according to the present disclosure is highly compatible with disposable endoscopes that widely use plastic materials. Furthermore, the present disclosure may be readily implemented by code updating of field programmable gate arrays of display units. Preferably, no hardware changes are required to the endoscope. Advantageously, the communication bus is protected from a wide range of high frequency noise and electrical interference.

The present disclosure may also relate to the following aspects, wherein each of the following aspects may be independently and arbitrarily combined with any of the above-mentioned aspects and claims.

1. An endoscope, comprising: a proximal endoscope handle or interface comprising a handle or interface housing, a working channel access port, and a printed circuit board, wherein the printed circuit board is housed inside the handle or interface housing; an insertion cord extending from a proximal endoscope handle or interface and comprising an insertion tube, a bending section, and a distal tip unit, wherein the distal tip unit comprises a camera module connected to a printed circuit board; a working channel extending from a working channel access port of an endoscope handle or interface to a distal end unit of an insertion cord; and a detector circuit configured to detect the presence of high frequency noise and electrical interference caused by electrosurgical tool use and operation in the working channel.

2. The endoscope of aspect 1, wherein the detector circuit comprises: a sensor portion configured to detect the presence of high frequency noise and electrical interference; and a circuit portion electrically connected with the sensor portion and configured to provide an output signal indicative of the presence of high frequency noise and electrical interference.

3. The endoscope of aspect 2, wherein the sensor portion is configured to input a voltage to the circuit portion, and the circuit portion is configured to output an output signal based on the voltage input from the sensor portion to the circuit portion.

4. The endoscope according to aspect 3, wherein the circuit portion is configured to set an upper limit threshold voltage and a lower limit threshold voltage, and change an output signal of the circuit portion when a voltage transmitted from the sensor portion is higher than the upper limit threshold voltage or lower than the lower limit threshold voltage.

5. The endoscope of any of aspects 2-4, wherein the circuit portion is integrated in a printed circuit board disposed in an endoscope handle or interface.

6. The endoscope of any one of aspects 2-5, wherein the circuit portion comprises a window comparator.

7. The endoscope of any one of aspects 2-6, wherein the sensor portion is positioned around the working channel so as to at least partially surround the working channel.

8. The endoscope of any of aspects 2-7, wherein the working channel is formed by a tip housing comprising a connector portion of the access port, the working channel tube, and the distal tip unit, and the sensor portion is positioned on an outer surface of the connector portion or on an outer surface of the working channel tube.

9. The endoscope of any one of aspects 2-8, wherein the sensor portion is a conductive portion and is configured to function as a capacitor.

10. An endoscope according to any of aspects 2 to 9, wherein the sensor portion is formed as a conductive foil or tape or a flexible printed circuit board so as to be bendable and shapeable so as to follow the outer contour of the working channel.

11. The endoscope of any one of aspects 2-10, wherein the sensor portion is disposed inside a proximal endoscope handle or interface.

12. A system, comprising: the endoscope according to any one of the preceding aspects 1 to 11; and a display unit connected with a printed circuit board housed in a handle or interface housing of the endoscope handle or interface, configured to communicate with a camera module provided in a distal end unit of the insertion cord via a communication bus, and configured to terminate communication via the communication bus when the detector circuit detects the presence of high frequency noise and electrical interference.

13. The system of aspect 12, wherein the display unit includes input circuitry including logic circuitry for communicating with a printed circuit board housed in a handle or interface housing of the endoscope handle or interface and a camera module disposed in a distal end unit of the endoscope, the input circuitry configured to receive the output signal indirectly or directly from the detector circuit.

14. The system of aspect 12 or 13, further comprising: an electrosurgical tool configured to operate with high voltage pulses to generate high frequency noise and electrical interference during operation.

15. The system of aspect 14, wherein the electrosurgical tool is configured to be inserted into a working channel of an endoscope, the high voltage pulses cause an electric field, and the electric field charges a sensor portion of the detector circuit when the electrosurgical tool is received and operated within the working channel.

Drawings

The disclosure is explained in more detail below using preferred embodiments and with reference to the accompanying drawings.

FIG. 1 is a plan view illustrating a system including an endoscope and a video processing device according to the present disclosure;

FIG. 1a is a perspective view of an embodiment of the video processing device of FIG. 1;

FIG. 1b is a front view of another embodiment of the video processing device of FIG. 1;

FIG. 2 is a schematic view illustrating electrical connections provided in an endoscope and display unit according to the present disclosure

And a schematic of a communication line;

FIG. 3 is a perspective view showing an endoscope handle of the endoscope in an open configuration;

FIG. 4 is a diagram showing the sensor portion and handle printed circuit in a detached state from the endoscope handle

An illustrative perspective view of a road board;

FIG. 5 shows a window comparator incorporated in a detector circuit in accordance with the present disclosure

Is a simplified diagram of the function of (a);

FIG. 6 illustrates a first embodiment of a circuit forming a detector circuit according to the present disclosure;

FIG. 7 illustrates a second embodiment of a circuit forming a detector circuit according to the present disclosure;

FIG. 8 shows a simplified diagram illustrating pulsing of an electrosurgical tool in a rapid pulse mode;

FIG. 9 illustrates one of the plurality of pulse bursts illustrated in FIG. 8;

FIG. 10 shows individual pulses in the pulse burst shown in FIG. 9;

FIG. 11 shows a simplified diagram illustrating pulsing of an electrosurgical tool in a slow pulse mode;

FIG. 12 illustrates one of the plurality of pulse bursts illustrated in FIG. 11;

FIG. 13 shows a flowchart of an embodiment of a noise detection method according to the present disclosure;

FIG. 14 shows a flow chart of another embodiment of a noise detection method according to the present disclosure;

and

Fig. 15 shows a modification of the embodiment of the noise detection method of fig. 14.

The drawings are schematic in nature and are used only to understand the disclosure. Features of different embodiments may be interchanged with one another.

Detailed Description

Further described, VPA 18 and variants thereof, denoted VPA 18a and VPA 18e, are configured to mitigate the effects of electrical noise resulting from the use of electrosurgical tools located in the working channel of endoscope 2. This effect is alleviated by: determining that electrical noise is present; and in response to the determination, preventing the camera module from malfunctioning by stopping transmission of the configuration signal from the VPA to the camera module in the endoscope 2.

In some variations, endoscope 2 includes an electrical noise detector and logic configured to transmit the detected noise signal to the VPA. The VPA may determine that electrical noise is present based on the detected noise signal or based on a mismatch between the configuration parameters transmitted from the output buffer and the configuration parameters read from the input buffer.

Advantages of the visualization system include, among other things, preventing or alleviating camera module failure while operating the electrosurgical tool, reducing the size of the insertion cord of the endoscope, and reducing the cost of the endoscope. Size and cost reduction may be achieved when malfunctions are alleviated by means that do not require the addition of an electrical shield between the electrosurgical tool and the communication wires in the endoscope, whether such shields include shielding braids of the communication wires or metallizing and grounding the working channel.

The endoscope 2 is preferably a disposable endoscope formed substantially from parts of plastic/polymeric material. The endoscope 2 comprises a proximal endoscope handle 4 designed to be held by an operator and configured to accommodate operating parts of the endoscope 2. Here, the presence of the handle 4 is a preferred embodiment. However, it is also possible to apply an interface instead of a handle, which interface is adapted to be coupled to the distal end of a robotic arm or the like. Since such an interface has the same function as a handle, but is basically only different in appearance, only the handle is shown in the drawings as a synonym for both the handle and the interface. Further, the endoscope 2 comprises an insertion cord 6 configured to be inserted into a body cavity of a patient. The insertion cord 6 comprises a (flexible/passively curved) insertion tube 8, a (actively actuatable) bending section 10 and a distal tip unit 12 extending in sequence from the endoscope handle 4.

At/in the distal end unit 12, a camera module 13 is provided. The camera module 13 includes image sensor circuitry 42 and an image sensor 14. The image sensor circuitry 42 is configured to implement the settings of the image sensor 14. The camera module 13 may include a light source such as a light emitting diode or an optical fiber connected to the light source so that a body cavity of a patient may be irradiated and inspected. Image sensor circuitry 42 may include, for example, voltage regulators, capacitors, and other passive devices to regulate the signals and light sources of the image sensor. The image captured by the image sensor 14 may be shown on the display 16 of the display unit 18. The endoscope 2 may be connected to the display unit 18 via a plug and socket connection 20. The endoscope 2 may comprise a plug which may be plugged into a socket of the display unit 18. It should be understood that display unit 18 need not include display 16. Alternatively, an external monitor/display may be provided that is not part of display unit 18 and is connected to display unit 18.

The endoscope 2 has an internal working channel 22. Working channel 22 is substantially formed by biopsy connector/Y-connector 76, a bendable/flexible polymer tube (i.e., working channel tube 65) connected to Y-connector 76, and the tip housing of distal tip unit 12 where working channel 22 forms an opening to the environment. The Y-connector 76 includes an access port 24 for introducing instruments into the working channel 22. A working channel tube 65 is provided in/within the insertion cord 6 and extends from a Y-connector 76 provided in the endoscope handle 4 towards the distal tip unit 12. Working channel 22 is accessible via an access port 24. In particular, electrosurgical tool 25 is an example of a minimal instrument that may be guided through working channel 22 into a patient's body cavity via Y-connector 76 and working channel tube 65. Thus, the operator can perform a medical procedure within the body cavity of the patient with the tool 25.

The endoscope handle 4 comprises two operating units 26, 28, namely a first operating unit 26 and a second operating unit 28, to actively steer/bend the bending section 10, thereby orienting the distal tip unit 12 in a determined direction. The endoscope handle 4 may alternatively comprise only one operating unit 26, 28. The operating units 26, 28 may be handle wheels or levers. In the illustrated embodiment, the operator may apply a rotational/turning force to both the first operating unit 26 and the second operating unit 28. As can be taken from fig. 1, the first operating unit 26 and the second operating unit 28 are coaxially arranged, i.e. rotatable about a common rotation axis. Both the first operating unit 26 and the second operating unit 28 are formed as handle wheels in fig. 1.

The distal tip units 12 may be oriented in different directions, respectively, by bending the bending section 10. The endoscope 2 shown in fig. 1 is basically a biplane bending endoscope. This means that the distal tip unit 12, or more specifically the bending section 10, may be bent in a first bending plane (e.g. in an up-down direction) and in a second bending plane (e.g. in a left-right direction). In particular, the first operating unit 26 may be operated by an operator to bend the distal end unit 12/bending section 10 in a first bending plane, and the second operating unit 28 may be operated by an operator to bend the distal end unit 12/bending section 10 in a second bending plane. The first bending plane is preferably perpendicular to the second bending plane. It should be appreciated that the endoscope 2 according to the present disclosure may also be a single plane bending endoscope.

To achieve the above bending movement, the bending section 10 may include a plurality of segments, wherein two adjacent segments (i.e., a pair of segments) among the plurality of segments may be connected via corresponding flexible hinge members, respectively. The curved section 10 may be molded as a single piece comprising segments and hinge members connecting the segments, as is known in the art. The curved section 10 may be largely covered by a flexible tubular outer cover member 30 to prevent contamination.

The endoscope 2 may comprise a steering wire 31 (not shown in fig. 1) for controlling the bending movement of the bending section 10. The control wire 31 guided in the additional function channel inside the insertion cord can be connected to the first operating unit 26 and/or the second operating unit 28. The steering wire 31 may extend through the entire insertion tube 8 and preferably the entire bending section 10 and be connected to the most distal segment or distal end unit of the bending section. By turning the first operating unit 26, the steering wire 31/steering wire section can be pulled and released and the distal end unit 12 can be tilted according to the direction in which the first operating unit 26 is rotated. In other words, by operating the first operating unit 26, the operator is able to tilt the distal tip unit 12 in the first bending plane by bending the bending section 10 accordingly. By turning the second operating unit 28, the steering wire 31/steering wire section can be pulled and released and the distal tip unit 12 can be tilted according to the direction in which the second operating unit 28 is rotated. In other words, by operating the second operating unit 28, the operator is able to tilt the distal tip unit 12 in the second bending plane by bending the bending section 10 accordingly.

The endoscope 2, and in particular the endoscope handle 4, further comprises two valves, namely a gas/water injection valve 32 and an aspiration valve 34. The endoscope handle 4 may alternatively comprise only one valve 32, 34. The gas/water injection valve 32 and the suction valve 34 are arranged side by side on a top surface 36 of a handle housing 38 (in particular formed of two half-shells) of the endoscope handle 4.

Fig. 1a shows a perspective view of a VPA 18a with a display 16, a socket 18b, a handle or bracket 18c and a housing 18d partially enclosing the display 16. Wires 46 may be connected to the receptacle 18b to present real-time images obtained by the camera module 13 using the display 16. The VPA 18a includes an image processing device configured to receive real-time images and, if necessary, convert these real-time images into a format suitable for the display 16. The image processing device includes logic operable to present a graphical user interface to allow a user to manipulate image data using a touch screen (e.g., display 16) and optionally output video signals to allow remote viewing of images presented with display 16. VPA 18a may also include memory with Graphical User Interface (GUI) logic embedded therein, as well as a video output board. A wireless interface may be provided. Example wireless interfaces include bluetooth and Zigbee controllers. The wireless interface may be configured to communicate with a display that is not integrated in VPA 18 a.

Fig. 1b shows a front view of VPA18e comprising housing 18 f. An optional display support interface 18g may be provided to physically mount a display support 18h connected to a display device 18i including a display 16. Display support interface 18g may be removed so that VPA18e may be separated from display device 18i. The display device 18i may then be placed in a convenient location such as an iv pole. Existing display devices 18i connected to VPA18e via cable or wirelessly may also be used.

Fig. 2 is a schematic diagram showing electrical connections and communication lines provided in the endoscope 2 and the display unit 18 according to the present disclosure. As can be seen in fig. 2, the endoscope handle 4 includes a handle printed circuit board (handle PCB) 40 housed inside a handle housing 38. The handle printed circuit board 40 is electrically connected to and in electrical communication with the camera module 13, and in particular with the image sensor circuitry 42 and the image sensor 14, via wires 44.

When endoscope 2 and display unit 18 are connected via plug and socket connection 20, display unit 18 is electrically connected and in electrical communication with handle printed circuit board 40 via wires 46 and is configured to power handle printed circuit board 40, image sensor circuitry 42, and image sensor 14. In particular, display unit 18 may communicate with image sensor 14 via a communication bus 48, which is used to transmit configuration information and may be referred to as a configuration bus. Image sensor circuitry 42 at the remote end unit 12 is configured to handle communications via a communications bus 48. The communication between the display unit 18 and the handle PCB 40 may alternatively be wireless and the handle PCB 40 may alternatively be battery powered. The images captured by the image sensor 14 may be transferred via a separate image data bus (not shown) to the display unit 18 where they are processed. For this purpose, the display unit 18 includes input circuitry 50 that includes logic for communicating with the handle PCB 40 and for receiving images captured by the image sensor 14. The input circuitry 50 may be a circuit board.

In this embodiment, the configuration bus may operate at about 200 kbits/s and the image data bus may operate at about 320 mbits/s. The configuration bus may be a serial bus and the image data bus may be a MIPI bus including one or more differential data lines. Some examples of serial communication buses include I2C and SCCB (serial camera control bus), both of which have proven to be suitable serial communication buses in accordance with the present disclosure. Parallel communication buses may also be used where the patch cord size allows for a larger communication bus.

In other embodiments, a single bus may be used to transmit configuration data and receive image data.

The input circuitry 50 may be implemented using logic circuitry, an FPGA (field programmable gate array) 52, or a DSP (digital signal processor), or the like. The input circuitry 50 includes noise mitigation logic 51 configured to implement the noise mitigation methods described with reference to fig. 13-15. Noise mitigation logic 51 is shown as part of FPGA52, but noise mitigation logic 51 may be embedded in or accessed by the memory of the logic circuit or DSP.

In particular, according to a preferred embodiment of the present disclosure, the input circuitry 50 is implemented using an FPGA 52. The display unit 18 is configured to display the processed image on the display 16. FPGA52 may include noise mitigation logic 51.FPGA52 may include an output buffer and an input buffer connected to a common pad. The output buffer is switched to generate a clock signal on a clock line of the bus. The input buffer is used to read the current state of the clock line. The same arrangement may be used for controlling the data lines of the bus.

The term "logic" as used herein comprises software and/or firmware executed on one or more programmable processing devices, application specific integrated circuits, field programmable gate arrays, digital signal processors, hardwired logic, or a combination thereof. Thus, the various logic may be implemented in any suitable manner and will remain unchanged from the embodiments disclosed herein, depending on the embodiment. Logic may include processing instructions embedded in a non-transitory machine-readable medium (e.g., memory).

As indicated in fig. 2, an electrosurgical tool 25 configured to be operated by high voltage pulses (e.g., in the range of 4kV to 5 kV) to generate high frequency noise and electrical interference during operation may be inserted into the working channel 22 via the access port 24. Electrosurgical tools 25 of this type are well known in the art and are commonly used, for example, for tissue cautery and may be directed through working channel 22 and out of working channel orifice/opening 56 provided in distal tip unit 12. During operation of the electrosurgical tool 25, the high voltage pulses cause a strong electric field (HF) that is experienced as noise on the communication bus 48. Noise may have a negative effect on the communication, i.e. may cause electrical interference. According to the present disclosure, noise causing electrical interference is designated as high-frequency noise and electrical interference. Since the working channel 22 is preferably made of a plastic material in accordance with the present disclosure, the working channel 22 itself does not provide a good/adequate shielding from high frequency noise and electrical interference. Thus, the communication bus 48 using the wires 44 guided/extended immediately/adjacent/near the working channel 22 inside the insertion rope 6 is quite susceptible to high frequency noise and electrical interference from the working channel. When the electrosurgical tool 25 is disposed distally relative to the working channel aperture 56 inside the body cavity of the patient, the image sensor circuitry 42 and the image sensor 14 are positioned relatively close to the electrosurgical tool 25 and thus close to the high frequency noise and electrical interference sources. As already mentioned, however, high frequency noise and electrical interference are present along the entire working channel 22 as a result of the cable 58 transmitting a voltage of about 4kV to 5kV to the tool end of the electrosurgical tool 25.

For a better understanding of the physical relationship between the working channel and the communication bus, it is noted that the outer diameter of the insertion rope may be less than 5mm, preferably less than 4mm and even 3mm or less. In cross section, the wall of the curved section, the wall of the tube forming the working channel and the camera module are comprised within the outer diameter. Furthermore, the lead 44 may abut the wall of the working channel tube and be separated from the electrosurgical tool 25 only by the thickness of the working channel tube wall. Since structures including wires and wall thicknesses prevent buckling of the distal end of the insertion cord and the insertion cord diameter is reduced to reduce the invasiveness of medical procedures, it is desirable to minimize the structures (e.g., wires and wall thicknesses) and reduce the outer diameter, which can increase noise picked up by the communication bus and exacerbate the problems addressed by the present solution.

Further, the display unit 18 is configured to write exposure data to the image sensor 14 via the communication bus 48, in particular the wire 44. The exposure data and other data that set the functions of the image sensor are referred to as configuration data. Configuration data may include shutter speed, orientation, white balance, etc. For this purpose, configuration data is written to registers provided in the image sensor. The registers may also be read. Thus, the VPA may write to a register and then read from the register to confirm that the data was written correctly.

In particular, during data transfer via the communication bus 48, data is written into one register in the image sensor 14 in, for example, four bytes including a device address, two register addresses, and configuration data. During operation of the electrosurgical tool 25, high frequency noise and electrical interference on the communication bus 48 may cause erroneous bit insertion and bit loss of data transmitted during data transmission.

Thus, as shown in fig. 2, an endoscope 2 according to the present disclosure may include a detector circuit 60 that detects the presence of high frequency noise and electrical interference in the working channel 22 caused by the use of the electrosurgical tool 25. The detector circuit 60 includes a sensor portion 62 that detects the presence of high frequency noise and electrical interference, and a circuit portion 64 electrically connected to the sensor portion 62. The sensor portion 62 is positioned adjacent the working channel 22 (particularly on the outer surface of the working channel tube 65 or Y-connector 76) so as to at least partially surround the working channel 22, as already indicated in fig. 2. The sensor portion 62 may be positioned on the working channel 22, preferably inside the handle housing 38. The sensor portion 62 may be positioned at least partially around a portion of the working channel 22, preferably inside the handle housing 38. The sensor portion 62 is a conductive portion or at least has a conductive surface that can establish a capacity charge. As shown in fig. 2, the circuit portion 64 of the detector circuit 60 may be included in the handle printed circuit board 40.

When a high-frequency voltage is present in the working channel 22, the sensor portion 62 is configured to input a detected noise signal (e.g., voltage) into the circuit portion 64. The circuit portion 64 is configured to provide an output signal that is communicated to the display unit 18. The output signal depends on the voltage input from the sensor portion 62 to the circuit portion 64. In particular, the output signal may indicate the presence of high frequency noise and electrical interference, or may indicate the absence of any high frequency noise and electrical interference. The output signal of circuit portion 64 serves as an input to display unit 18, which may temporarily terminate some or all of the communications on communication bus 48 based on the input signal. In one variation, the display unit or VPA 18 stops transmission of configuration data, but continues to receive image data based on the configuration data last transmitted to the camera module (e.g., before noise is detected). The noise is not perceived by the camera module. Because of the timing of the high frequency voltages and the timing of the communications when the electrosurgical tool 25 is actuated, the output signals may be transmitted to the VPA 18 prior to transmitting the configuration data to the camera module while electrical noise is present. Additionally, a stop command/signal may be transmitted via the communication bus to cause the camera module to stop receiving configuration data.

The output signal is transmitted from the handle printed circuit board 40 to the display unit 18 via the wire 46. In this manner, an existing bus (substantially for transmitting images) like communication bus 48 may be used to transmit the output signals, and additional communication buses need not be provided in accordance with the present disclosure. The output signal of the circuit portion 64 may be regarded as a trigger signal. In particular, when the output signal/trigger signal goes low, a communication line like the clock line of the communication bus 48 may be pulled down. Alternatively, the output signal may also be transmitted directly to the display unit 18. The present disclosure provides embodiments of algorithms/methods that are performed when an output signal indicative of the presence of high frequency noise and electrical interference is received, either directly or indirectly, by input circuitry 50 of display unit 18. Display unit 18 is configured to continuously check working channel 22 for the presence of high frequency noise and electrical interference that may affect communication bus 48. As will be described in greater detail below, display unit 18 terminates communication over communication bus 48 in the presence of high frequency noise and electrical interference for at least a particular period of time.

Fig. 3 shows the handle housing 38 of the endoscope handle 4 in an open configuration (i.e., with one of the two halves forming the handle housing 38 removed). It can be seen that working channel tube 65, which forms part of working channel 22, extends from Y-connector 76 into insertion cord 6. In addition, it can be seen that a number of other (functional) tubes like the water jet tube 66, the irrigation tube 68, the air blow tube 70, the conduit 72 including the electric wire 44, and the manipulation wire 31 are guided into the insertion cord 6.

In fig. 3, the sensor portion 62 is placed on a Y-connector 76 that includes the access port 24. The Y-connector 76 further includes a first inlet passage 73, a second inlet passage 74 incorporated into the first inlet passage 73, and a common outlet passage 75. The second inlet passage 74 is at an angle of less than 90 ° relative to the first inlet passage 73. The outlet channel 75 forms an extension of the first inlet channel 73. The first inlet channel 73, the second inlet channel 74 and the outlet channel 75 are thus arranged approximately Y with respect to each other. The working channel tube 65 is connected to the outlet channel 75. The electrosurgical instrument 25 may be inserted into the working channel tube 65 via a second inlet channel 74 and an outlet channel 75. It can thus be said that the second inlet channel 74, the outlet channel 75, the working channel tube 65 and the tip housing of the distal tip unit 12 in combination form the working channel 22, and that the second inlet channel 74 serves as the inlet port 24. Three possible arrangements/positions/locations (1), (2) and (3) of the sensor portion 62 are shown, wherein the sensor portion 62 is drawn only at position (1). As can be seen in fig. 3, according to position (1), the sensor portion 62 is located around/on the outer surface of the second inlet channel 74. Depending on position (2), the sensor portion 62 may also be located around the Y-connector 76 in the transition region between the second inlet channel 74 and the outlet channel 75. Depending on position (3), the sensor portion 62 may also be located around the outlet channel 75 of the Y-connector 76. It should be appreciated that the sensor portion 62 may also be disposed about the working channel tube 65 that is connected to the outlet channel 75. In summary, the sensor portion 62 is preferably disposed inside the handle housing 38 of the endoscope handle 4 so as to be proximate to the handle printed circuit board 40. However, it should also be understood that the present disclosure is not limited to this configuration, and that the sensor portion 62 may be disposed substantially anywhere in the vicinity of the working channel tube 65 (i.e., also throughout the insertion cord 6).

The sensor portion 62 may be made of a conductive material. In particular, the sensor portion 62 is formed as a conductive foil or tape in fig. 3 and is bent or shaped to follow the contour of the working channel 22. For example, sensor portion 62 may be made of copper foil or flexible PCB positioned proximate to the outer surface of working channel 22, particularly proximate to the outer surface of Y-connector 76 or working channel tube 65. The sensor portion 62 may be glued to the outer surface of the working channel 22. The sensor portion 62 may have a thickness of 0.5cm ² And 2cm ² Between, in particular about 1cm ² In order to provide a capacitance sufficient for detecting high frequency noise and electrical interference and to (at least partially) surround the working channel 22 in order to be able to better detect possible communicationHigh voltage pulses on bus 48 that cause high frequency noise and electrical interference. In the configuration shown in fig. 3, the sensor portion 62 (and in particular the surface of the sensor portion 62) is positioned relatively close to the source of high frequency electrical noise (the electrosurgical tool 25 or its cable 58) when the electrosurgical tool 25 is inserted into the working channel 22. Thus, the sensor portion 62 is charged by an electric field generated from high frequency noise and electric interference generated by the electrosurgical tool 25 operating inside the working channel 22. Without being bound by theory, it is believed that the capacitor is formed by the electrosurgical tool 25 and the sensor portion 62, wherein the wall of the working channel and the air between the electrosurgical tool 25 (or cable 58 thereof) and the sensor portion 62 define the dielectric of the capacitor.

As best shown in fig. 4, the sensor portion 62 is preferably disposed around/on the outer surface of the Y-connector 76. In order to be charged by the high frequency noise and electrical interference generated by the electrosurgical tool 25 operating inside the working channel 22, the sensor section 62 should have a distance from the inside of the Y-connector 76 of less than 3mm, in particular less than 2mm, for example a distance between 1mm and 2 mm. Accordingly, the wall thickness of the Y-connector 76 should be appropriately adjusted. Alternatively, the surface area of the sensor portion 62 may be increased to increase its sensitivity.

Fig. 4 also shows that the sensor portion 62 is connected to the handle printed circuit board 40 via a cable 78. In addition, fig. 4 shows a first cable conduit 72 extending from the handle printed circuit board 40 into the insertion cord 6 and a second cable conduit 80 extending from the handle printed circuit board 40 towards the display unit 18.

As mentioned above, the detector circuit 60 outputs a signal, i.e. the VPA18, may be used to determine a noise detection signal in the presence of electrical noise. The noise detection signal may be generated by the detector circuit 60 when the input signal exceeds a threshold and is communicated by changing the state of the lines of the configuration bus 48. The sensor portion 62 may include a capacitor 84, but other sensors that detect significant changes in the amount of electrical energy may be used, for example, wires that act as antennas, inductors, and the like. The circuit portion 64 potentially amplifies the input signal so that it can be used by the rest of the circuit, sets a threshold value, and generates an output signal when the input signal (or amplified input signal) exceeds the threshold value.

In some embodiments, circuit portion 64 is a window comparator. The window comparator has two thresholds instead of one. The function of the window comparator is better understood with reference to fig. 5, in which the input voltage 90 (solid line) generated by the sensor portion 62 and the output signal 94 (dash-dot line) generated by the circuit portion 64 are shown. The window comparator has an upper threshold voltage 96/u1 (dashed line) and a lower threshold voltage 92/u2 (dotted line). The horizontal axis represents time and the vertical axis represents the amplitude of the voltage. The input voltage and the output voltage do not have to be on the same voltage scale. The upper threshold voltage 96/u1 and the lower threshold voltage 92/u2 define threshold voltages for determining high frequency noise and electrical interference. It can be seen that when the input voltage 90 is in the window (between the upper threshold voltage 96/u1 and the lower threshold voltage 92/u 2), the output signal 94 is "high", which is considered to be undetected for high frequency noise and electrical interference, and when the input voltage 90 is outside the window (above the upper threshold voltage 96/u1 or below the lower threshold voltage 92/u 2), the output signal 94 is "low", which is considered to be present for high frequency noise and electrical interference. More generally, the output signal of the circuit portion 64 changes state when the input voltage transmitted from the sensor portion 62 transitions from inside the window to outside the window, and vice versa. In a single threshold comparator, either an upper or lower threshold voltage may be used to generate the output/trigger signal 94.

Having described the functionality of the window comparator, attention is now directed to the detection of noise. In some embodiments described with reference to fig. 6 and 7, noise is detected by a detector circuit. In other embodiments, noise is detected by noise mitigation logic based on the state of the input buffers of FPGA 52 or the equivalent bits of circuit 50 corresponding to the output buffers of the corresponding lines of the bus.

Fig. 6 and 7 show electrical diagrams of two embodiments of the detector circuit 60. The two embodiments are based on the same concept but are implemented slightly differently. Both detector circuits 60 comprise a capacitor 84 (i.e. a sensor portion 62) which is electrically connected to a window comparator circuit (comprised in the circuit portion 64) which is shown in fig. 6 as an IC (integrated circuit) chip 86 and in fig. 7 as two operational amplifiers (op-amps) (op-amp (operational amplifier)) 124, 126. The output of the window comparator circuit is communicated to display unit 18 via communication bus 48, for example using a clock line of communication bus 48.

Functionally, the capacitor 84 is charged by high frequency noise and electrical interference generated during operation of the electrosurgical tool 25 within the working channel 22. As described with reference to fig. 5, the upper threshold voltage 92 and the lower threshold voltage 96 define the range (detection window) of high frequency noise and electrical interference that triggers the noise detection signal. Once the input voltage 90 is outside the range between the upper threshold voltage 92 and the lower threshold voltage 96, the output voltage 94 goes low and may further pull down connections in the communication bus 48, such as the clock line of the communication bus 48.

IN electrical detail, the capacitor 84 is electrically connected to pins 1 IN-and 2in+ of an IC chip 86, which may be a dual voltage comparator integrated circuit, IN fig. 6. Upper threshold voltage 96 is electrically connected to pin 1in+ of IC chip 86 and lower threshold voltage 92 is electrically connected to pin 2IN-. The voltage supply Vcc is applied to pin Vcc+ and grounded to pin Vcc-. Capacitor 98 acts as a filter and zener diode 100 acts as a voltage regulator. Resistor 122 pulls up output 94 until either of pins 1 or 7 goes low, thereby pulling down output 94.

Similarly, capacitor 84 in FIG. 7 is electrically connected to the inverting terminal of op-amp 124 and to the non-inverting terminal of op-amp 126 via optional resistor 102. The upper threshold voltage 96 in fig. 7 is electrically connected to the non-inverting terminal of the operational amplifier 124 and the lower threshold voltage 92 is electrically connected to the inverting terminal of the operational amplifier 126. The voltage supply Vcc is applied to the positive power supply of the operational amplifiers 124, 126 and to the negative power supply of the operational amplifiers 124, 126. The zener diodes 104, 106 together with the resistor 102 form a zener clamp to prevent the voltage from exceeding a prescribed value, wherein the resistor 108 is designed to limit the current to a safe value for the zener diodes 104, 106. The capacitor 110 acts as a filter.

Further, in both fig. 6 and 7, a bias circuit may be provided at the input of the window comparator circuit electrically connected to the capacitor 84 using a voltage divider having two resistors 112, 114, such that the voltage at the input of the window comparator circuit may be quickly biased to a voltage value designed by the bias. In particular, the values of resistors 112, 114 may be set equal, so the designed voltage value for the bias may be set to 1/2Vcc.

The lower threshold voltage 92 and the upper threshold voltage 96 are preferably set using a voltage divider network formed by three resistors 116, 118, 120. The three resistors 116, 118, 120 may be selected to have equal resistance values. Thus, the voltage may drop one third of the voltage supply Vcc across each resistor. Thus, in this example, the upper threshold voltage 96 may be set to 2/3Vcc and the lower threshold voltage may be set to 1/3Vcc. Resistors 116, 118, and 120 may be set at any value to adjust the lower threshold voltage 92 and the upper threshold voltage 96.

Additionally, a pull-up resistor 122 may be provided at the output of the window comparator circuit, which may be connected to the same power supply as the window comparator or to a separate power supply available in the handle PCB 40.

The circuits in fig. 6 and 7 show only two exemplary designs of detector circuit 60. The peripheral electrical components around capacitor 84 and window comparators 86, 124, 126 may be adjusted according to different design requirements. For a single threshold design, pins 1 through 4 or 5 through 8 of IC chip 86 may be used, and one of op-amps 124 and 126 may be used.

In an alternative practical embodiment, no detector circuit 60 is provided in the endoscope 2. According to the alternative embodiment, input circuitry 50 continuously checks or monitors the communication lines on communication bus 48. The communication bus 48 between the display unit 18, the handle PCB 40 and the camera module 13 in the distal end unit 12 may be based on a master-slave protocol. The input circuitry 50 at the display unit 18 is preferably the master device and may pull down or raise (i.e., may set up a signal of) a communication line on the communication bus 48. The input circuitry 50 may then continuously check or monitor whether the (signal of the) communication line is actually set as originally. The input circuitry 50 is configured to determine whether the communication line is in an unexpected state, i.e., in a state that has not been initially set by the input circuitry 50. This may be interpreted by the input circuitry 50 as the presence of high frequency noise and electrical interference on the communication bus 48, which is described below as a mismatch or collision.

In particular, input circuitry 50 as a master may control the clock line and transmit clock signals via the clock line. The handle PCB 40 may be a slave device and may receive a clock signal from the master device via a clock line. If the output signal of the clock line set by the input circuitry 50 is pulled low, for example, but the clock line of the communication bus 48 is suddenly in an unexpected high state, the input circuitry 50 may consider it to be present on the communication bus 48 as high frequency noise and electrical interference. This comparison of the output signal of the clock line set by the input circuitry 50 with the input signal of the clock line received from the handle PCB 40 is performed by the input circuitry 50. The input/output signal mismatch is indicative of noise and may be described below as collision.

A comparison signal indicative of the result of the comparison may be generated by the input circuitry 50. Once the difference of the comparison exceeds a predetermined threshold, the input circuitry 50 may pull the comparison signal "low", which may be considered to be the presence of high frequency noise and electrical interference on the communication bus 48.

In summary, the method according to an alternative practical embodiment is implemented on the input circuitry 50 of the display unit 18 and is configured to continuously check the high frequency noise and electrical interference on the communication bus 48 by monitoring the communication lines on the communication bus 48. Preferably, the input circuitry 50 compares the output signal of the clock line set by the input circuitry 50 (as a "controller/master") with the input signal of the clock line from the handle PCB 40 (as a "peripheral/slave") to determine the presence of high frequency noise and electrical interference on the communication bus 48 without the use of the detector circuit 60.

As discussed above, the present disclosure was developed in view of the nature of electrosurgical (e.g., plasma surgical) tools 25 used in endoscopic surgery. Typically such electrosurgical tools 25 emit electrical noise signals comprising a (independent) pulse burst/bursts, including high voltage pulses and a wide range of frequencies, and there is a risk that individual pulses in the pulse burst(s) may interfere with the communication bus 48 (e.g., the I2C bus).

Electrosurgical tools may operate in different modes to perform a desired medical procedure. For example, fig. 8 shows pulsing of the electrosurgical tool 25 in a rapid pulsing mode. In this mode, the electrosurgical tool 25 emits current pulses at a rapid rate (e.g., 125 MS/s). It can be seen that when the electrosurgical tool 25 is delivering current pulses at a rapid rate in this mode, a plurality of pulse bursts 130 occur periodically. Two pulse bursts 130 are spaced apart by about 60ms (which begins). Fig. 9 shows one burst 130 (of the plurality of burst 130 shown in fig. 7) in more detail. The individual pulses are substantially more closely spaced at the beginning of the pulse burst 130 compared to the end of the pulse burst 130. This is more apparent when looking at fig. 10, which shows the transition/change from an initial faster independent pulse to a slower independent pulse in a burst. The two slower independent pulses are spaced apart by about 50 mus as can be seen in fig. 10. Figures 11 and 12 show the pulsing of the electrosurgical tool 25 in a slow pulsing mode. As can be seen in fig. 11, the two pulse bursts 130 are spaced apart about 800ms (which begins) in the slow pulse mode. In fig. 12, it can be seen that a single burst 130 lasts about 200ms in the slow pulse mode. The high voltage pulses of the individual pulses in both the fast pulse mode and the slow pulse mode may cause strong electric fields that may cause high frequency noise and electrical disturbances to propagate in the working channel 22 and affect the communication bus 48, which may lead to the writing of erroneous data and/or erroneous addresses in the image sensor 14. The HF electrosurgical tool 25 has been used in APC (argon plasma coagulation) mode to measure the waveforms of the individual pulses, which waveforms may also represent the general characteristics of the high frequency noise and electrical interference generated in the common HF electrosurgical tool.

Referring to fig. 13, a method of mitigating the effects of high frequency noise is provided. According to this method, display unit 18 terminates communication with image sensor 14 over communication bus 48 in the presence of high frequency noise and electrical interference for at least a specified period of time. The display unit 18 considers the described properties of the electrosurgical tool 25 with respect to pulsations in both the fast pulse mode and the slow pulse mode. The method is implemented by noise mitigation logic 51 in display unit 18. The functionality of the noise mitigation logic is illustrated by the flowcharts depicted in fig. 13-15.

In general, methods to mitigate the effects of high frequency noise are timed based on the profiling of the noise. As described above, in the example of high frequency noise, the bursts of pulses are spaced 60 milliseconds apart. Thus, two bursts span 120 milliseconds. If more than 60 milliseconds have passed after the last burst detected, it can be concluded that the high frequency pulse has ended, but a safer approach is to wait more than 120 milliseconds (two burst periods plus the duration of the burst), for example 125 milliseconds, during which there will be two or three bursts if the tool is operational, so if no burst is detected during this time, it is safely concluded that the tool is not operating or is not operating in a noise-forming mode. The 125 ms secure time will be referred to as "t2" and corresponds to a 60 ms burst period. If the tool is parsed and the profile has different burst periods, t2 will be adjusted accordingly. Of course, a time greater than one cycle but less than about two cycles plus the burst duration may be used.

The method periodically senses signal collisions (the wire having a value different from the commanded value or the endoscopic guidewire indication sensor detecting noise) during a short time window (e.g., t 1) to detect collisions indicative of high frequency pulse bursts and optionally prevent termination of communications on the configuration bus if the collisions are random events. If noise is detected, the method terminates communication on the configuration bus using one or more of several techniques discussed below. Once the noise ceases for a safe period of time (e.g., t 2), the method resumes communication on the configuration bus. The method may be improved to avoid detecting collisions during signal transitions, e.g. transition edges based on rise/fall time. Embodiments of the method are described in more detail with reference to fig. 13-15.

In the flowchart shown in fig. 13, the following abbreviations are used:

a: start to

B: is a noise detection signal received?

C: continuing operation of the communication bus

D: return to

E: blocking the communication bus and looking for another noise at time t1

F: is another noise detection signal received?

G: restarting operation of a communication bus

H: return to

I: waiting time t1

J: is another noise detection signal received during t 1?

K: waiting time t2

L: is another pulse burst detected during t 2?

M: restarting operation of a communication bus

N: return to

+: is that

-: whether or not

Specifically, at B, the noise mitigation logic first determines whether noise is present (step S1). When the noise mitigation logic receives the noise detection signal, it may be determined that noise is present. The noise detection signal may be an output signal received indirectly or directly from detector circuit 60 or a comparison signal generated by input circuitry 50 of display unit 18, as described below.

In the event no noise detection signal is received ("no"), operation of the communication bus 48 continues at C. In the event that a noise detection signal is received ("yes"), the communication bus 48 is immediately blocked at E, i.e., communication on the communication bus 48 is temporarily terminated/stopped. Thus, the independent pulses are prevented from causing interference to the communication bus 48. In some embodiments, when a particular communication bus protocol permits this, if noise is detected while transmission of command/configuration data packets is in progress, a stop condition command is transmitted on the bus to properly end transmission of the data packets, and then the bus is blocked in response to a command from noise mitigation logic.

Then at F (as step S2), the noise mitigation logic checks/looks for another noise/another noise detection signal for a first short period of time t1 (e.g., 1 ms). In the case where another noise/another noise detection signal is not received during the first short period t1 ("no"), the noise detection signal received in step S1 is random noise. In particular, the individual pulses of a pulse burst are typically spaced apart by about 50 μs. Thus, the first short period of time is set to be sufficiently longer than 50 μs (e.g., 1 ms) so that one certainly knows that the individual pulses detected in S1 are not part of a pulse burst. If it is determined that the noise detection signal received in S1 is random noise (i.e., if another noise is not received during time t 1), communication on the communication bus 48 continues at G.

In the event that another noise/another noise detection signal is received during the first short period of time t1 ("yes"), the noise mitigation logic is configured to wait again for the first short period of time t1 and determine at J (step S3) whether another noise/another noise detection signal is received during said period of time t 1. This process is repeated in the case of another noise ("yes"). Accordingly, the noise mitigation logic is configured to wait until another noise detection signal is not received within the time period t 1. When another noise detection signal is not received within the time period t1, this means that the end of the pulse burst 130 has been reached.

In a next step, at K, the noise mitigation logic is configured to wait a second long period of time t2, e.g., 125ms. The second long period of time is set such that another burst of pulses in the fast pulse mode will be detected. Thus preventing communication of the communication bus 48 from continuing during rapid burst mode operation of the electrosurgical tool 25. In case another burst of pulses 130 is detected during the second long period t2 at L (step S4), the method returns to detection during period t1 until the end of the burst is detected and then waits again for the second long period t2. This process is repeated as long as another burst of pulses 130 is detected during the second long period t2. Operation of the communication bus 48 is resumed at M only if another burst of pulses 130 is not detected during the second long period t2.

In a practical embodiment of the present disclosure, the method shown in fig. 13 is implemented by noise mitigation logic on an FPGA 52 forming part of the input circuitry 50 of the VPA18 or the display unit. FPGA 52 can be readily updated and configured to implement and perform the methods of the present disclosure. When noise is detected based on a mismatch or conflict on a line of the configuration bus, after the noise stops, the line returns to its commanded state and the noise mitigation logic may thus detect the absence of a match or conflict. Basically, when noise occurs and when noise disappears, the noise changes the state of one or more of the lines and both changes can be detected by the noise mitigation logic when monitoring the respective input buffers.

Referring now to fig. 14, another embodiment of a method of mitigating the effects of high frequency noise will be described with reference to a flowchart 140. Prior to practicing the method, at 142, VPA 18 verifies that the endoscope is connected. At 146, noise mitigation logic 51 on FPGA52 waits for confirmation that endoscope 2 is connected. At 148, noise mitigation logic 51 queries whether a connection is made, for example, by receiving an indication of a change in the state of the wire, as is known in the art. If the endoscope is not connected, the noise mitigation logic 51 returns to 146 and then periodically checks again until the endoscope is connected. The foregoing is preferred, but noise can also be detected and mitigated by monitoring the buffer without checking whether the endoscope is connected.

At 150, noise mitigation logic 51 begins to check if there is a conflict by first determining at 152 whether to intentionally switch any line in the communication bus. In one example, the lines include an SCL line or an SDA line corresponding to the clock line and the data line. In this embodiment, the communication bus comprises a configuration bus for transmitting commands to the image sensor. A separate image data bus with a faster data transfer rate is provided to allow the image sensor to transfer images to VPA 18. It has been empirically found that while noise is observed on the configuration bus, the same noise source does not appear to generate noise on the image data bus.

At 154, noise mitigation logic 51 ignores conflicts that may be the result of such switching by ignoring edges of transitions caused by switching lines of the configuration bus, e.g., by waiting for X clock cycles at 156. In one example, X is equal to 4 cycles. The number of cycles is not entirely arbitrary, being a number high enough to prevent false positives but short enough to detect noise quickly. Depending on the clock rate and the hardware used, more or less cycles may be sufficient to ensure that edges of the switching transition are not considered in assessing whether a collision occurs.

After X clock cycles, the noise mitigation logic 51 compares the state of the lines of the configuration bus (input state) with the state of the previous command (output state) at 160. If these states match, i.e., are the same, then there is no conflict yet. On the other hand, if the states do not match, then at 162, the noise mitigation logic 51 asserts a high frequency noise flag. Asserting the high frequency noise flag may simply mean that the logic state of the register switches from deasserted to asserted. Of course, the status of the flag may be tracked and changed in any manner known in the art. In one example, the FPGA has pads for each line (e.g., SCL and SDA) of the configuration bus. The pads are connected to the input and output buffers of the FPGA. The noise mitigation logic 51 "remembers" the last state to which the output buffer zone was set and reads the input buffer, then compares the two states and determines whether a conflict occurs based on the comparison. The natural state of the wires may be a high impedance high state.

After determining that the conflict occurred, at 164, the noise mitigation logic 51 determines whether the conflict is random. To do so, at 166, noise mitigation logic 51 again performs a comparison during time period t 1. If the comparison does not indicate that another conflict occurred, the mismatch is random and the noise mitigation logic 51 deasserts the high frequency noise flag at 168. If the comparison indicates that another conflict has occurred, then the noise mitigation logic 51 determines at 170 that the conflict is not random and that a burst of high frequency voltage is in progress and waits for the end of the burst. It does this by periodically comparing the input buffer with the output buffer during period t1 at 172 until the comparison indicates no conflict.

Time t1 is set relative to the pulse rate in the high frequency mode of the electrosurgical tool. The burst period is between 12 milliseconds and 15 milliseconds, so t1 is selected to be between 5% and 10% of the burst period, which provides a sufficient balance between responsiveness and computational cost.

At 174, noise mitigation logic 51 waits for another burst during time period t2 at 176. If another burst is detected (by performing the comparison again), the noise mitigation logic 51 returns to 170 to search for the end of the burst. If another burst is not detected, the noise mitigation logic 51 de-asserts the high frequency noise flag at 168.

When the high frequency noise flag is asserted, the noise mitigation logic 51 pauses the configuration of the image sensor to prevent configuration data transmitted via the configuration bus from becoming corrupted by noise and thus causing the camera module to fail. The camera module continues to transmit image data via the image data bus based on the last configuration data set received by the image sensor. When the high frequency noise flag is de-asserted, the noise mitigation logic 51 again sends the configuration data to the image sensor. The configuration data may include, for example, automatic Exposure Settings (AES) to control exposure settings of the image sensor on a substantially image-by-image basis. While the transmission of the configuration data is suspended, the image sensor does not receive the configuration data (such as an AES command), but continues to generate an image using the last transmitted AES command.

The conflict may occur in different ways. If the detector circuit 60 is provided in the endoscope 2, the detector circuit 60 may lower the output signal and thus the SCL line or the SDA line. By forcing a state change on either line, the detector circuit causes a change at the input buffer such that a conflict is determined to have occurred.

Noise caused by the electrosurgical tool 25 may also change the state of the configuration bus. A change in state of a command that is not from VPA 18 causes a change at the input buffer such that a conflict is determined to have occurred.

The noise mitigation logic 51 may suspend the configuration of the image sensor in different ways. First, the noise mitigation logic 51 may only stop transmitting commands via the configuration bus. Second, noise mitigation logic 51, which is a configuration bus master, may transmit a stop command via the configuration bus. The stop command provides a suitable way to instruct the image sensor to stop reading the configuration bus and thus prevents problems when noise occurs in the transmission (when the data packet has been at least partially transmitted). Third, noise mitigation logic 51, which is a configuration bus master, may set the state of these lines to end the transmission and prevent subsequent packets from being transmitted. One or more of these options may be implemented based on the configuration bus protocol and possibly based on the timing of the ongoing transmission.

Fig. 15 depicts a flowchart 180 showing a simpler embodiment of a method of mitigating the effects of high frequency noise described with reference to fig. 14. In this embodiment, the method does not test for random collisions/mismatches. If the high frequency noise flag is asserted, the method searches for the end of the burst and then checks during period t2 before de-asserting the high frequency noise flag.

Additional exemplary embodiments of the foregoing aspects of the present disclosure are set forth in the following exemplary entries:

1. a system, comprising: a display unit (18), the display unit (18) comprising input circuitry (50) configured to communicate with the handle or interface printed circuit board (40) and the image sensor circuitry (42) via a communication bus (48); and a communication bus (48) connecting the endoscope (2) with the display unit (18) and configured to enable communication between the image sensor circuitry (42), the handle or interface printed circuit board (40) and the input circuitry (50); wherein the input circuitry (50) of the display unit (18) is configured to check, preferably continuously or pulsed, for high frequency noise and electrical disturbances on the communication bus (48).

2. The system of item 1, wherein the input circuitry (50) is configured to terminate communication via the communication bus (48) in the presence of high frequency noise and electrical interference on the communication bus (48).

3. The system of clause 1 or 2, wherein the communication between the input circuitry (50), the handle or interface printed circuit board (40) and the image sensor circuitry (42) is master-slave based, wherein the input circuitry (50) is a master and the handle or interface printed circuit board (40) and the image sensor circuitry (42) are slaves.

4. The system of item 3, wherein the input circuitry (50) is configured to initially set a communication line output signal of a communication line of the communication bus (48) and compare the communication line output signal with a communication line input signal of the communication line received from the handle or interface printed circuit board (40) to determine the presence of high frequency noise and electrical interference on the communication bus (48).

5. The system of item 4, wherein the communication line output signal is an output clock signal of a clock line of the communication bus (48) and the communication line input signal is an input clock signal of the clock line of the communication bus (48), and the input circuitry (50) is configured to initially set the output clock signal and compare the output clock signal with the input clock signal received from the handle or interface printed circuit board (40) to determine that high frequency noise and electrical interference is present on the communication bus (48).

6. The system of clause 4 or 5, wherein the input circuitry (50) is configured to generate a comparison signal based on a comparison of the communication line output signal and the communication line input signal, and to determine that high frequency noise and electrical interference are present if the comparison signal exceeds a predetermined threshold.

7. The system according to any one of items 1 to 3, wherein the endoscope (2) further comprises: a working channel (22) configured for inserting an electrosurgical tool (25) into a body cavity of a patient; and a detector circuit (60) configured to detect high frequency noise and electrical interference caused by use and operation of the electrosurgical tool (25) in the working channel (22) and affecting the communication bus (48).

8. The system of item 7, wherein the detector circuit (60) is configured to provide an output signal indicative of the presence of high frequency noise and electrical interference on the communication bus (48).

9. The system of any of the preceding items 1 to 8, wherein the input circuitry (50) is configured to:

a) Determining whether a noise detection signal is received; and

b) In the event of a noise detection signal being received, the communication bus (48) is blocked.

10. The system of item 9, wherein the input circuitry (50) is further configured to:

d) Restarting the operation of the communication bus (48) in case no further noise detection signal is received in step c); and

e) In case a further noise detection signal is received in step c), waiting until no noise detection signal is received within a first predetermined period of time, i.e. until the end of the pulse burst (130) emitted by the electrosurgical tool (25) is reached.

11. The system of item 10, wherein the input circuitry (50) is further configured to:

f) At the end of the pulse burst (130), waiting a second predetermined period of time and determining whether another pulse burst (130) is detected during the second predetermined period of time;

g) Restarting operation of the communication bus (48) in case no further burst of pulses (130) is detected in step f); and

h) In case a further pulse burst (130) is detected in step f), step e) is repeated until no further pulse burst (130) is detected in step f).

12. The system of any one of the preceding items 1 to 11, further comprising an electrosurgical tool (25) configured to be inserted into the working channel (22) of the endoscope (2) and to transmit a high frequency electrical noise signal comprising pulse bursts (130) at a wide range of frequencies during operation.

13. A display unit (18) comprising input circuitry (50) configured to check, preferably continuously or pulsed, for high frequency noise and electrical interference on a communication bus (48) via which the display unit (18) is connectable to an endoscope (2) and which enables communication between the input circuitry (50) and the endoscope (2).

14. The display unit (18) of item 13, wherein the input circuitry (50) is configured to terminate communication via the communication bus (48) in the presence of high frequency noise and electrical interference on the communication bus (48).

15. A method of checking, preferably continuously or pulsed, for high frequency noise and electrical interference on a communication bus (48) via which a display unit (18) can be connected to an endoscope (2) and which enables communication between the display unit (18) and the endoscope (2), and which preferably terminates communication via the communication bus (48) in the presence of high frequency noise and electrical interference on the communication bus (48).

16. An endoscope (2), the endoscope comprising: a proximal endoscope handle or interface (4) comprising a handle or interface housing (38), a working channel access port (24), and a printed circuit board (40), wherein the printed circuit board (40) is housed inside the handle or interface housing (38); an insertion cord (6) extending from the proximal endoscope handle or interface (4) and comprising an insertion tube (8), a bending section (10) and a distal tip unit (12), wherein the distal tip unit (12) comprises a camera module (13) connected to a printed circuit board (40); a working channel (22) extending from a working channel access port (24) of the endoscope handle or interface (4) to the distal end unit (12) of the insertion cord (6); and a detector circuit (60) configured to detect the presence of high frequency noise and electrical interference in the working channel (22) caused by use and operation of the electrosurgical tool (25).

17. The endoscope (2) of item 16, wherein the detector circuit (60) comprises: a sensor portion (62) configured to detect the presence of high frequency noise and electrical interference; and a circuit portion (64) electrically connected to the sensor portion (62) and configured to provide an output signal indicative of the presence of high frequency noise and electrical interference.

18. The endoscope (2) according to item 17, wherein the sensor portion (62) is configured to input a voltage to the circuit portion (64), and the circuit portion (64) is configured to output the output signal based on the voltage input from the sensor portion (62) to the circuit portion (64).

19. The endoscope (2) of item 18, wherein the circuit portion (64) is configured to set an upper threshold voltage (96, U1) and a lower threshold voltage (92, U2), and to change an output signal of the circuit portion when a voltage transmitted from the sensor portion (62) is higher than the upper threshold voltage (96, U1) or lower than the lower threshold voltage (92, U2).

20. The endoscope (2) of any of the claims 17 to 19, wherein the circuit portion (64) is integrated in a printed circuit board (40) provided in the endoscope handle or interface (4).

21. The endoscope (2) of any of claims 17-20, wherein the circuit portion (64) comprises a window comparator (84, 124, 126).

22. The endoscope (2) of any of the claims 17-21, wherein the sensor portion (62) is positioned around the working channel (22) so as to at least partially encircle the working channel (22).

23. The endoscope (2) of any of the claims 17-22, wherein the working channel (22) is formed by a tip housing comprising a connector portion (76) of the access port (24), a working channel tube (65) and a distal tip unit (12), and the sensor portion (62) is positioned on an outer surface of the connector portion (76) or on an outer surface of the working channel tube (65).

24. The endoscope (2) of any of claims 17-23, wherein the sensor portion (62) is a conductive portion and is configured to function as a capacitor (84).

25. The endoscope (2) of any of the claims 17 to 24, wherein the sensor portion (62) is formed as a conductive foil or tape or a flexible printed circuit board so as to be bendable and formable to follow the outer contour of the working channel (22).

26. The endoscope (2) of any of the claims 17-22, wherein the sensor portion (62) is arranged inside the proximal endoscope handle or interface (4).

27. A system, comprising: the endoscope (2) according to any one of the preceding items 16 to 26; and a display unit (18) connected to a printed circuit board (40) housed in a handle or interface housing (38) of the endoscope handle or interface (4), configured to communicate with a camera module (13) provided in a distal end unit (12) of the insertion cord (6) via a communication bus (48), and configured to terminate communication via the communication bus (48) when the detector circuit (60) detects the presence of high frequency noise and electrical interference.

28. The system of item 27, wherein the display unit (18) comprises input circuitry (50) comprising logic circuitry for communicating with a printed circuit board (40) housed in a handle or interface housing (38) of the endoscope handle or interface (4) and a camera module (13) provided in a distal end unit (12) of the endoscope (2), the input circuitry (50) being configured to receive the output signal indirectly or directly from the detector circuit (60).

29. The system of clauses 27 or 28, further comprising: an electrosurgical tool (25) configured to be operated by high voltage pulses to generate high frequency noise and electrical interference during operation.

30. The system of item 29, wherein the electrosurgical tool (25) is configured to be inserted into the working channel (22) of the endoscope (2), the high voltage pulses cause an electric field, and the electric field charges the sensor portion (62) of the detector circuit (60) when the electrosurgical tool (25) is received and operated inside the working channel (22).

As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," "can," "contains," and variants thereof are intended as open transition terms that do not exclude the possibility of additional actions or structures. In contrast, as used herein, the term "composition" is intended as a closed transition term that excludes the possibility of additional actions or structures.

List of reference numerals

2. Endoscope with a lens

4. Endoscope handle

6. Insertion rope

8. Insertion tube

10. Bending section

12. Distal end unit

13. Camera module

14. Image sensor

16. Monitor/screen

18. Display unit

19. Image processing apparatus

20. Plug and socket connection

22. Working channel

24. Access port

25. Electrosurgical tool

26. A first operation unit

28. A second operation unit

30. Cover member

31. Control wire

32. Gas/water injection valve

34. Suction valve

36. Top surface

38. Handle shell

40. Printed circuit board of handle

42. Image sensor circuitry

44. Electric wire

46. Electric wire

48. Communication bus

50. Input circuit board

51. Noise mitigation logic

52FPGA

56. Working channel orifice

58. Cable wire

60. Detector circuit

62. Sensor part

64. Circuit part

65. Working channel tube

66. Water spray pipe

68. Flushing pipe

70. Air blowing pipe

72. First cable duct

73. A first inlet channel

74. A second inlet channel

75. Outlet channel

76Y-shaped connector

78. Cable wire

80. Second cable duct

84. Capacitor with a capacitor body

86IC chip

90. Input voltage

92. Lower threshold voltage

94. Output voltage

96. Upper threshold voltage

98. Capacitor with a capacitor body

100. Zener diode

102. Resistor

104. Zener diode

106. Zener diode

108. Resistor

110. Capacitor with a capacitor body

112. Resistor

114. Resistor

116. Resistor

118. Resistor

120. Resistor

122. Pull-up resistor

124. First operational amplifier

126. Second operational amplifier

130. Pulse bursts.

Claims

1. A visualization system, comprising:

video processing apparatus (18) comprising input circuitry (50) and noise mitigation logic (51), the input circuitry (50) being adapted to communicate with an image sensor (14) of an endoscope (2) via a communication bus (48), wherein,

The noise mitigation logic (51) is configured to cease transmitting configuration data to the image sensor via the communication bus (48) in the presence of high frequency noise and electrical interference on the communication bus (48).

2. The visualization system according to claim 1, wherein the configuration data comprises at least one configuration parameter of the image sensor (14).

3. The visualization system of claim 2, wherein the video processing device (18) receives the image generated by the image sensor (14), and wherein the video processing device (18) continues to receive the image generated by the image sensor (14) while ceasing to transmit configuration data to the image sensor (14) via the communication bus (48).

4. A visualization system according to any of claims 1 to 3, wherein the noise mitigation logic is configured to periodically check for high frequency noise and electrical interference on the communication bus (48).

5. The visualization system of claim 4, wherein the communication between the input circuitry (50) of the video processing device (18) and the image sensor (14) is based on a master-slave arrangement, wherein the video processing device (18) is a master device.

6. The visualization system of claim 1, wherein the input circuitry (50) is configured to set a communication line output signal of a communication line of the communication bus (48) and compare the communication line output signal with a communication line input signal of the communication line received from the endoscope (2) to determine the presence of the high frequency noise and electrical interference on the communication bus (48).

7. The visualization system of claim 6, wherein the communication line output signal is an output clock signal of a clock line of the communication bus (48) and the communication line input signal is an input clock signal of the clock line of the communication bus (48), and the input circuitry (50) is configured to initially set the output clock signal and compare the output clock signal with an input clock signal received from the endoscope (2) to determine that the high frequency noise and electrical interference is present on the communication bus (48).

8. The visualization system of claim 6 or 7, wherein the input circuitry (50) is configured to generate a comparison signal based on a comparison of the communication line output signal and the communication line input signal, and to determine that the high frequency noise and electrical interference are present if the comparison signal exceeds a predetermined threshold.

9. A visualization system according to any one of claims 1 to 3, further comprising the endoscope (2), wherein the endoscope (2) further comprises a working channel (22) and a detector circuit (60), the working channel (22) being configured for insertion of an electrosurgical tool (25), and the detector circuit (60) being configured to detect high frequency noise and electrical interference caused by operation of the electrosurgical tool (25).

10. The visualization system of claim 9, wherein the detector circuit (60) is configured to provide a noise detection signal via the communication bus (48) indicating the presence of the high frequency noise and electrical interference on the communication bus (48).

11. The visualization system of claim 10, wherein the noise mitigation logic (51) is configured to:

a) Determining whether the noise detection signal is received; and

b) The communication bus (48) is blocked if the noise detection signal is received.

12. The visualization system of claim 11, wherein the noise mitigation logic (51) is further configured to:

e) In case a further noise detection signal is received in step c), waiting until no noise detection signal is received within the first predetermined period of time, which indicates that the end of the pulse burst (130) transmitted by the electrosurgical tool (25) has been reached.

13. The visualization system of claim 12, wherein the noise mitigation logic (51) is further configured to:

f) At the end of the pulse burst (130) in step e), waiting a second predetermined period of time and determining whether another pulse burst (130) is detected during the second predetermined period of time;

14. The visualization system of claim 9, wherein the detector circuit (60) comprises: a sensor portion (62) configured to detect the presence of the high frequency noise and electrical interference; and a circuit portion (64) electrically connected with the sensor portion (62) and configured to provide an output signal indicative of the presence of the high frequency noise and electrical interference.

15. The visualization system of claim 14, wherein the circuit portion (64) is configured to set a threshold voltage (92, 96) and change a state of the output signal when a voltage transmitted from the sensor portion (62) exceeds the threshold.

16. The visualization system of claim 14, wherein the circuit portion (64) is configured to set an upper threshold voltage (96, U1) and a lower threshold voltage (92, U2), and to change an output signal of the circuit portion when a voltage transmitted from the sensor portion (62) is above the upper threshold voltage (96, U1) or below the lower threshold voltage (92, U2).

17. A method of checking, preferably continuously or pulsed, for high frequency noise and electrical interference on a communication bus (48) via which a video processing device (18) is connectable to an endoscope (2) and which enables communication between the video processing device (18) and the endoscope (2), and which preferably terminates communication via the communication bus (48) in the presence of high frequency noise and electrical interference on the communication bus (48).

18. An endoscope (2) comprising

A proximal endoscope handle or interface (4) comprising a handle or interface housing (38), a working channel access port (24), and a printed circuit board (40), wherein the printed circuit board (40) is housed inside the handle or interface housing (38);

An insertion cord (6) extending from the proximal endoscope handle or interface (4) and comprising an insertion tube (8), a bending section (10) and a distal end unit (12), wherein the distal end unit (12) comprises a camera module (13) connected to the printed circuit board (40);

a working channel (22) extending from a working channel access port (24) of the endoscope handle or interface (4) to a distal end unit (12) of the insertion cord (6); and

a detector circuit (60) configured to detect the presence of high frequency noise and electrical interference in the working channel (22) caused by use and operation of the electrosurgical tool (25).

19. The endoscope (2) of claim 18 wherein the detector circuit (60) comprises: a sensor portion (62) configured to detect the presence of the high frequency noise and electrical interference; and a circuit portion (64) electrically connected with the sensor portion (62) and configured to provide an output signal indicative of the presence of the high frequency noise and electrical interference.

20. The endoscope (2) of claim 19, wherein the sensor portion (62) is configured to input a voltage to the circuit portion (64), and the circuit portion (64) is configured to output the output signal based on the voltage input to the circuit portion (64) from the sensor portion (62).

21. The endoscope (2) of claim 20, wherein the circuit portion (64) is configured to set an upper threshold voltage (96, U1) and a lower threshold voltage (92, U2) and to change an output signal of the circuit portion when a voltage transmitted from the sensor portion (62) is above the upper threshold voltage (96, U1) or below the lower threshold voltage (92, U2).

22. The endoscope (2) according to any of claims 18 to 21, wherein the circuit portion (64) is integrated in the printed circuit board (40) provided in the endoscope handle or interface (4).

23. The endoscope (2) of any of claims 18-22, wherein the circuit portion (64) comprises a window comparator (84, 124, 126).

24. The endoscope (2) of any of claims 18-23, wherein the sensor portion (62) is positioned around the working channel (22) so as to at least partially encircle the working channel (22).

25. The endoscope (2) according to any of claims 18 to 24, wherein the working channel (22) is formed by a connector portion (76) comprising the access port (24), a working channel tube (65) and a tip housing of the distal tip unit (12), and the sensor portion (62) is positioned on an outer surface of the connector portion (76) or on an outer surface of the working channel tube (65).

26. The endoscope (2) of any of claims 18-25, wherein the sensor portion (62) is a conductive portion and is configured to function as a capacitor (84).

27. Endoscope (2) according to any of claims 18 to 26, wherein the sensor portion (62) is formed as a conductive foil or tape or a flexible printed circuit board so as to be bendable and shapeable following the outer contour of the working channel (22).

28. An endoscope (2) according to any of claims 18-27, wherein the sensor portion (62) is arranged inside the proximal endoscope handle or interface (4).