JP2014057898A - Monitoring of esophageal arrangement of capsule endoscope with tether - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a better technique for monitoring an axial direction position of a capsule endoscope.SOLUTION: A scan soft endoscope includes a tether (22) attached to a capsule (20). The tether (22) controls the arrangement of the capsule (20) in a body cavity such as an esophagus. When the capsule (20) is caused to pass and move in the body cavity in an axial direction, a scanner (26) in the capsule (20) optically scans a neighborhood tissue on an internal surface in the body cavity. In response to a marker on the tether (22), a non-contact sensor (638) measures relative positions in the body cavity of the tether (22) and the capsule (20). The form of the marker can be either analog or digital, and the sensor (638) can be either magnetic or optical. A wiper (670) is selectively provided, and when the tether (22) has passed through the sensor (638) and is pulled out from the body cavity, a body fluid is removed from the tether (22). A fluid pulse is supplied to a far end of the tether (22) to cause the expansion of the body cavity so that the free movement of the capsule in the body cavity is promoted.

Description

  Barrett's esophagus (BE) is a precancerous state of the esophagus, a precursor of esophageal cancer. The standard practice of diagnosing Barrett's esophagus often uses a soft endoscopic procedure by blowing air into the esophageal lumen. The normal esophagus is usually light pink, while the stomach has a slightly dark pink color. Barrett's esophagus usually appears as a slightly darker pink area above the lower esophageal sphincter (LES) that separates the stomach from the esophagus.

  Since this condition has been found to be a precursor to esophageal adenocarcinoma, BE is preferably diagnosed early. Therefore, even if millions of esophageal conditions with chronic heartburn and gastric reflux are needed, it is desirable to provide a general screening procedure for this condition. However, because Barrett's esophagus and early stage cancer can develop without obvious symptoms, the condition can be identified and treated as early as possible to prevent the onset, ie provide a curative treatment for cancerous symptoms Mass screening has been proposed as the only viable method. Unfortunately, the current cost of conducting flexible endoscopy by physicians compared to the number of predictive candidates for esophageal screening, and the medical fees associated with mass screening, is currently unrealistic due to the associated costs I have to.

  What is needed is a more efficient and cost effective way to identify people with Barrett's esophagus. Only a physician can perform an esophageal examination using a conventional flexible endoscope, and thus this procedure is relatively expensive. It would be preferable to develop another scanning technique that does not require implementation by a physician and instead can be performed by a trained medical technician or nurse. In fact, automating the evaluation of images generated by imaging the inner surface of the esophagus immediately proximal to the LES so that the presence of Barrett's esophagus can be automatically detected in real time or immediately after the scanning operation. Is also desirable.

  To facilitate mass screening of individuals who may have Barrett's esophagus, it is desirable to use a screening device that can be easily introduced into the esophagus without causing any pharyngeal reflexes. Ideally, this screening device should be realized in a capsule-shaped housing so that it can be easily swallowed with a glass of water. Therefore, this device must be small enough for most patients to swallow. Furthermore, although such devices can be reused if properly sterilized, it would be desirable to use a screening device that is sufficiently low in price so that it can be discarded after a single use.

  The earlier related application discloses a method of monitoring a patient's position in the esophagus with an endoscope that is well suited to provide images that can be used for esophageal condition assessment and thereby detect BE. . In this initial method, a tether attached to a capsule endoscope containing an imaging device passes over a wheel that rotates as the capsule moves axially in the esophagus, and the capsules in the esophagus The position is continuously monitored. The axial position of the capsule is important in order to be able to locate the area of interest in the esophageal internal surface image and to axially scale all of the captured panoramic images. However, the measurement of the axial position depends on the frictional contact between the tether and the measuring wheel. There are three reasons why this method cannot produce sufficiently accurate results. In this earlier method described, the tether needs to remain in tension and the measurement technique relies on friction without friction between the measurement wheel and the movable tether. Slippery saliva and mucus in the human oral cavity and esophagus can adhere to the tether and cause slippage between the rotating measuring wheel and the tether. In addition, the physician performing the procedure may want to feel the progress of the tethered capsule endoscope as it passes through the lower sphincter and other parts of the esophagus, and is disclosed as a measurement wheel (pinch wheel). The additional applied tension generated by the) is likely to disturb the feel. Similarly, the doctor may want to repeatedly move the capsule endoscope up and down in the esophagus, and easily incorporates a measurement error based on friction between the measurement wheel and the tether into the mechanical system. Any hysteresis during the measurement can be an additional source of error.

"AutoStitch", Matthew Brown, http://www.cs.ubc.ca/mbrown/autostitch/autostitch.html

  Therefore, a better technique for monitoring the axial position of the capsule endoscope is desired. The method used should monitor the movement of the capsule by detecting the movement of the tether without actually making contact between the tether and the axial position monitoring device. The presence of saliva and mucus should have minimal impact on the monitoring technique used, and the feel when the capsule endoscope moves up and down will be interfered with by the equipment used to monitor the capsule position It must be easily experienced by a doctor.

  An SFE (optical scanning endoscope) includes a scanning capsule having a scanning device and a tether coupled to the capsule to control the position of the scanning capsule within a body cavity. As a result of bodily fluid covering the surface of the tether, no error is introduced and at least the relative position of the scanning capsule is monitored to avoid disturbing the “feel” of the doctor controlling the position of the scanning capsule within the body cavity Therefore, a new method to realize this function has been developed. Thus, the method allows for relative position monitoring of the scanning capsule within the body cavity. A tether having a distal end coupled to the capsule extends out of the body cavity and carries the scanning signal generated within the scanning capsule that is convenient for generating an image of the interior surface of the body cavity. The method includes providing an indication of position along the axial length of at least a portion of the tether. Without requiring physical contact with the tether, the sensor is responsive to the marker, and the marker is automatically sensed to generate a position signal indicative of the position of the tether, i.e., the axial placement of the scanning capsule in the body cavity.

  At least one non-numeric visible reference mark is provided on the tether to indicate the predicted reference position. The reference mark thus allows the user to manually position the capsule near the desired position based on the visual indication provided by the non-numeric visual reference mark on the tether. Although not required, the body cavity can include the esophagus. In the case of the esophagus, this predicted reference position corresponds to a position on the tether that indicates when the capsule is placed near the gastroesophageal junction in the esophagus. An additional plurality of non-numeric visible reference marks can be provided both distally and proximally of the at least one non-numeric visible reference mark to visually indicate positions or distances on either side of the predicted reference position.

  In an exemplary embodiment, automatically sensing a sign to generate a position signal in response to a magnetic field variation parameter generated by the sign on the tether may include using a magnetic sensor. it can. The generated position signal may be either a digital position signal or an analog position signal, both of which indicate a current position along the axial length of the tether near the magnetic sensor.

  In another exemplary embodiment, an optical sensor can be used to generate a position signal in response to an optical parameter of the marker that varies along the axial length of the tether. Again, the step of generating the position signal may generate either a digital position signal or an analog position signal, both of which are the current position along the axial length of the tether near the photosensor. Indicates. The indicator can include an optical code that generates a position signal in response to at least one parameter selected from the group of parameters. These parameters are the optical code color sensed by the optical sensor, the digital value indicated by the optical code, the light intensity reflected from the optical code compared to the light intensity reflected from the background area, and the digital information. The pattern of the optical code to be transmitted, the relative dimensions of the mark with the optical code, the shape of the mark with the optical code, the light dispersed by the optical code in contrast to the light dispersed from the background area, and reflected by the optical code Or the wavelength of light absorbed.

  In yet another exemplary embodiment, an additional sensor can be provided to monitor the label on the tether to increase the resolution by which the relative position of the capsule within the body cavity is determined.

  Providing the indicator can include applying the indicator by attaching the indicator to the tether as a longitudinally extending tape, or by applying the indicator to the tether as a longitudinally extending coating. Optionally, the label can be protected by a protective coating applied thereon. In some exemplary embodiments, the method can include providing a scraper to gently wipe body fluid from the tether before the tether is removed from the body cavity and passes through the position sensor.

  For some applications, the exemplary method includes determining a reference position of the capsule within the body cavity relative to the marker to determine the position of the capsule within the body cavity. For example, the reference position can be determined by moving the capsule to a known position within the body cavity based on an image of the internal surface of the body cavity. Placing the capsule in a known position, i.e. indicating the reference position, then uses that reference position to determine the next position of the capsule when the tether is used to move the capsule within the body cavity To do.

  Another aspect of the present technology is directed to an exemplary device for measuring the relative position of a capsule used to scan an internal surface of a body cavity to generate an image. The instrument includes a tether and a non-contact position sensor that are generally consistent with the above method.

  Yet another aspect of the present technology is directed to intracavity interests regarding images generated by a scanning device in a capsule having a proximal end extending outwardly of the body cavity and coupled to a tether used to move the capsule. It is directed to an exemplary method for measuring the axial extent of a region. The method includes the step of measuring the distance that the capsule moves through the body cavity by the tether by monitoring the movement of the tether past a sensor located outside the body cavity. A series of images of the internal surface of the body cavity is taken when the capsule is moved in the body cavity axis direction using a tether. A region of interest on the interior surface of the body cavity is detected in the series of images, and a first position of the capsule in the body cavity corresponding to the start of the axial region of interest and a second corresponding to the end of the axial region of interest. The axial extent of the region of interest is measured with reference to the distance between the first position and the second position at which the tether moves the capsule. The following disclosure is an apparatus for executing this distance measurement function.

  Yet another aspect of the present technology is directed to a method of using a capsule having a scanning device that images the interior surface of the esophagus, where the capsule moves the capsule through the esophagus and through the gastroesophageal junction. Combined with a tether for letting. In this method (and with respect to corresponding devices), a tether is used to move the capsule through the esophagus to a location near the gastroesophageal junction. Next, a pressurized fluid pulse is delivered to the area near the capsule. Pressurized fluid pulses cause voluntary dilatation of the lower esophagus, thereby facilitating the passage of the capsule through the gastroesophageal junction and movement into and out of the patient's stomach, while using a scanning device within the capsule. Imaging the internal surface of the esophagus.

  This summary has introduced in a simplified form some concepts that are described in further detail in the following description. This summary is not, however, intended to identify key or essential features of the claimed subject matter or to assist in determining the scope of the claimed subject matter.

  Various aspects and attendant advantages of one or more exemplary embodiments and modifications thereto will be more readily appreciated as the same becomes better understood by reference to the following detailed description taken in conjunction with the accompanying drawings. Like.

FIG. 3 is a schematic diagram illustrating the esophagus and stomach, and illustrating how one body cavity can be easily manipulated using the present invention. 1B is a schematic diagram of a portion of the esophagus and stomach of FIG. 1A showing how the present invention is controllably positioned to manipulate a desired position of the esophagus to detect a BE condition. FIG. FIG. 2 is an enlarged perspective view of an embodiment of the present invention, and is a view of a FOV (relative wide angle field of view) provided by a scanning device used therein. 1 is a block diagram of the functional flow of signals within a scanning system according to the present invention useful for monitoring an internal surface of a lumen in a patient, providing a diagnosis, and providing treatment. FIG. FIG. 2 is a diagram of a scanning device embodiment having a scanning optical fiber drive actuator with a microlens used in connection with the present invention as a light beam scanning device with a scanning lens. FIG. 4 is a schematic diagram of a point light source imaging embodiment illustrating a change in imaging spot diameter at different scanning angles in connection with a scanning device used in the present invention. It is the schematic of the scanning point light source illuminating device equipped with the time series photodetector and imaging lens used for the scanning apparatus of this invention. It is the schematic of the scanning light beam illuminating device provided with the scanning lens and detector used for the scanning apparatus of this invention. 1 is a schematic diagram of a configuration for a scanning device that uses a bundle of optical fibers and a single concentric optical fiber. FIG. In a side schematic view of a scanning device having detection using a distal red green blue (RGB) light filter and stereo geometry and the ability to subtract background scatter using front and side facing spatial detectors. is there. FIG. 5 is a schematic end view of a scanning device having detection using a distal red green blue (RGB) light filter and stereo geometry and the ability to subtract background scatter using front and side facing spatial detectors. is there. Of a scanning device having detection using distal light deflection filters and volumetric geometry and the ability to enhance signals from surface tissue on the inner surface of the lumen using front and side spatially spaced detectors FIG. A scanning device having detection using distal light deflection filters and volumetric geometry and the ability to enhance signals from surface tissue on the inner surface of the lumen using front and side facing spatially located detectors It is an end surface schematic. FIG. 2 is a schematic diagram of a configuration of a scanning apparatus that is capable of acquiring a pseudo-stereoscopic image by disposing a photodetector having a fiber optic position sensor distally and a proximal optical fiber collector proximally; 1 is a schematic diagram of a fiber optic scanning system for use with the present invention using radiation from visible and UV laser sources combined with a dichroic filter. FIG. 1 is a schematic diagram of a fiber optic system for use with the present invention using radiation from visible and IR laser sources coupled in series with a fiber optic coupler. FIG. 1 is a top view of one embodiment of a thin film or MEMS (microelectromechanical) system scanning device that can be used in the present invention. FIG. 8B is a side cross-sectional view of one embodiment of a thin film or MEMS (microelectromechanical) system scanning device that can be used in the present invention, taken along section line 8B-8B in FIG. 8A. FIG. FIG. 8B is an end view of one embodiment of a thin film or MEMS (microelectromechanical) system scanning device that can be used with the present invention, taken along section line 8C-8C in FIG. 8A. FIG. 6 is an end view of another embodiment including a pair of thin film parallel cantilevers for illuminating the interior surface of the lumen. FIG. 4 is a diagram of a physician performing automatic scanning and diagnostic evaluation of a patient's esophagus using the present invention that may occur during mass screening of a general population targeting BE. 1 is a block diagram of functional input / output elements of a fiber optic scanning system for use with the present invention. FIG. 1 is a functional block diagram of an integrated cancer imaging, screening and biopsy system with optical therapy delivery and monitoring capabilities using a capsule and scanning device according to the present invention. FIG. 1 is a functional block diagram of an integrated cancer imaging, screening, and diagnosis system with stereographic surgery support and display capabilities using a capsule and scanning device according to the present invention. FIG. A side view of an exemplary embodiment of a non-contact optical sensor used to measure the position of the tether, i.e., the position of the scanning capsule coupled to the tether within the patient's esophagus, in response to an optical marker provided on the tether. FIG. 2 is a side schematic view of an exemplary embodiment of a non-contact magnetic sensor used to measure the position of a tether and a scanning capsule within a patient's esophagus in response to a magnetic marker provided on the tether. FIG. FIG. 2 is an exemplary schematic block diagram illustrating how a non-contact sensor that monitors tether and capsule placement is coupled to functional components of an SFE (scanning fiberscope) master. How an exemplary elastic scraper is used to wipe saliva and mucus from the tether when the tether is removed from the patient's esophagus and passes through a non-contact sensor that measures the position of the tether and capsule in the esophagus It is a schematic front view of a part of a tether shown. FIG. 3 is a schematic view of a capsule with an attached balloon and showing a balloon inflated in the lumen. 1 is a schematic view of a capsule having electrodes that cause peristalsis of muscle tissue that advances the capsule through the lumen. FIG. 1 is a schematic view of a capsule having a tether that includes an annular channel through which a biopsy instrument, such as a cytology brush, passes and advances to take biological tissue from the inner surface of the lumen. FIG. Pyramid for simultaneous lateral imaging of opposing lumen inner surfaces, showing how the tether can be used to rotate the capsule when a complete view of the lumen inner surface needs to be covered 1 is a schematic view of a capsule having a mold mirror. An exemplary analog pattern applied to a tether that allows a non-contact sensor to determine the position of the tether and attached capsule within the esophagus, for example based on an analog signal generated by an optical sensor responsive to the analog pattern FIG. An exemplary digital pattern applied to a tether that allows a non-contact sensor to determine the position of the tether and attached capsule within the esophagus, for example based on a digital signal generated by a light sensor responsive to the digital pattern FIG. Schematic of an exemplary embodiment that includes a dual light sensor with a lens to respond to a two-color optical pattern applied to the tether to determine the relative position of the tether / capsule within a body cavity, such as the esophagus. FIG. 1 is a schematic cut-away view of an exemplary tether with data applied on a data layer protected by a transparent coating. FIG. FIG. 22B is a cross-sectional view of the tether, data layer, and protective coating taken along section line 22B of FIG. 22A. FIG. 5 is an exemplary view of a tether with visible marks that indicate the predicted portion of the tether that must be inserted into the esophagus so that the capsule is positioned near the gastroesophageal junction where the esophagus is coupled to the stomach. FIG. 6 is a schematic illustration of an exemplary embodiment including a passage that carries a pressurized pulse of air (or other liquid) to a proximal point of the capsule so that the esophagus spontaneously expands. FIG. 6 is a schematic diagram of another exemplary embodiment including a nearby outer tube used to deliver a pressurized pulse of air (or other liquid) to a proximal point of the capsule. FIG. 6 is a schematic diagram of another exemplary embodiment in which an outer tube is used to slide over a tether and carry a pressurized pulse of air (or other liquid) to a proximal point of the capsule. .

  The figures and disclosed embodiments are not limiting.

  Exemplary embodiments are illustrated in the referenced figures of the drawings. The embodiments and figures disclosed herein are to be understood as illustrative rather than limiting. No limitation with respect to the scope of the present technology or the following claims shall be attributed to the examples shown in the drawings or the discussion within this specification.

Exemplary Application of Scanning Capsule An exemplary embodiment of a scanning capsule is a solution for providing a relatively low-cost general population mass screening for initially detecting BE without requiring physician interaction However, this embodiment is also useful for scanning, providing diagnostics, providing treatment, and monitoring the treatment status so provided on the inner surface of almost all lumens of the patient's body. It will be clear that this is applicable. Thus, the following discussion often emphasizes the application of scan capsules in the detection of BE, but the application of the instrument is not limited to that particular application.

  FIG. 1A includes a schematic diagram 10 showing the stomach 12, the esophagus 14, and the lower esophageal sphincter (LES) 16. The LES 16 normally serves as a check valve, allowing the food swallowed to the esophagus 14 to pass freely into the stomach 12, but normally acid and food go back from the stomach 12 into the esophagus 14. Is prevented. However, as mentioned in “Background of the Invention”, those suffering from chronic heartburn and gastroesophageal reflux often experience BE as a result of gastric acid passing through the LES 16 and into the lower part of the esophagus 14. A patient suffering from BE can be detected by determining whether the inner surface of the lumen, including the esophagus 14, has changed from its normal light pink color to a dark pink color in the region 18 just above the LES 16. it can. The exemplary scanning capsule allows easy scanning of the region 18 in the esophagus 14 and produces an image in which a dark pink color of the internal surface clearly showing BE is present. More importantly, as discussed in more detail below, a scanning capsule may allow the scanning process to be performed in an automated manner, so that a technician or nurse trained in the procedure It is intended that the detection of BE can be completed by a medical practitioner such as that, and usually no direct interaction with a doctor is required.

  A method that can scan the esophagus is illustrated in FIG. 1B. As shown therein, a capsule 20 of a size and configuration suitable for this purpose has been advanced through the esophagus 14 and has just passed into the stomach 12. Capsule 20 extends upward through esophagus 14 and is connected to a tether 22 that exits the patient's mouth. The capsule housing 24 is made of a plastic material that is biocompatible with dimensions about the size of a large vitamin tablet, eg, 15 mm long by 7 mm in diameter, and is not affected by gastric acid or other biological fluids. The tether 22 is very flexible and has a relatively small diameter, for example about 1 mm. Within the housing 24, the capsule 20 includes an actuator 28 that drives the scanning device 26 to scan the inner surface of the lumen in the FOV (field of view) 30. When used to determine whether a patient has BE, the capsule 20 is typically removed through the LES 16 so that the FOV 30 covers the area 18. That is, the image of the region 18 provided by the scanning device 26 is evaluated to indicate whether the tissue on the inner surface of the esophagus 14 has turned to a dark pink color indicating BE. It will also be apparent that when the capsule 20 is first lowered toward the stomach 12, the internal surface of the esophagus 14 is scanned and imaged.

  FIG. 2 illustrates further details of this embodiment of the capsule 20. Some of the other exemplary embodiments of the capsule are discussed below. Because the front or distal end 32 of the housing 24 is optically transparent, the light emitted by the oscillating optical fiber including the scanning device 26 in the exemplary embodiment is an optical system 34 that includes a plurality of lenses. And the light reaches the inner surface of the esophagus or other lumen where the capsule 20 is placed. The inner surface can be illuminated by the scanning device 26 using light in other wavelength bands, but in the exemplary embodiment, the inner surface of the lumen is illuminated using white light. The light reflected from the inner surface is detected by a plurality of RGB (red, green, and blue) sensors 36r, 36g, and 36b, respectively. White light used to illuminate the inner surface of the esophagus or lumen is transmitted to the scanning device 26 through an optical fiber (not shown separately) disposed within the tether 22. Signals generated by the plurality of RGB sensors are sent back through leads (not shown) in the tether 22 for processing to generate an image corresponding to the portion of the scanned internal surface. In an alternative exemplary embodiment discussed below, light reflected from the internal surface is transmitted proximally through an optical fiber in the tether to a detector outside the patient's body.

  The exemplary embodiment of FIG. 2 also includes a position sensor 38, provided by a signal source (not shown) external to the patient's body by generating a signal indicating the position and optionally orientation of the capsule 20 within the patient's body. Respond to external signals. Suitable position sensors that are responsive to electromagnetic signals are available, for example, from Ascension Technology. The position sensor 38 may be responsive to an electromagnetic field, an RF signal, an optical signal of a wavelength selected to pass through tissue and to the lumen, or other suitable signal. Alternatively, the position sensor 38 can be replaced with a signal source, which is also used in conjunction with an external sensor (not shown) to determine the position and optionally the orientation of the capsule 20 within the patient. Has been. An external signal source or position sensor is placed at a specific location on the patient's body to provide a reference by bandaging the signal source or position sensor to a specific location on the patient's torso.

  A chemical sensor 40 is optionally included to sense chemical parameters. For example, the chemical sensor 40 can detect the hydrogen ion concentration in the lumen, that is, the pH. Alternatively or additionally, the chemical sensor can include a temperature sensor to monitor the internal temperature of the lumen. Similarly, a pressure sensor can be used in addition to or instead of a chemical sensor, and thus it is intended to represent any one or all of these sensors.

As an additional option, a selectively releasable connection 42 is provided, allowing the capsule connection to be pneumatically or electrically released from the tether when desired. Thus, when disconnected from the tether, the capsule will be transported through the body cavity, and if the lumen is associated with the digestive tract, the capsule will pass through and be excreted. The releasable connection is activated by a pressurization pulse that is propagated from an external source (not shown) through a lumen (not shown) in the tether 22 or is actuated by an electrical signal. The electrical signal can be used to magnetically actuate the releasable connection 42 using a current provided through a lead in the tether. A similar releasable coupling, or alternatively, near the proximal end of the tether can be provided to release the tether and capsule together and pass through the lumen.
System processing overview

  FIG. 3 illustrates a system 50 with external equipment for processing the signals generated by the various components inside the capsule, and how the signals used to control the system are these components. Indicates whether it is input. In order to provide integrated imaging functionality and other functionality, the system 50 thus allows these components that are external to the patient and components that are in the capsule (ie, some of which are The components in the dotted line 52 are optionally divided according to the application used. Block 54 thus describes the functional components that can be placed within the capsule. As shown, these components are comprised of illumination optics, one or more electromechanical scanning actuators, one or more scanning device control actuators, and one or more scanning devices for scanning device operation control. Motion detectors, photodetectors for imaging the region of interest (ROI) (if there is an optical path in the tether to transmit light reflected from the inner surface of the lumen to the outer detector, these As well as, optionally, additional photodetectors for diagnostic and therapeutic and monitoring purposes (which can also be placed outside of the capsule and patient). It should be noted that with respect to system 50, only functional components that are actually needed for a particular application, such as esophageal imaging, may be included. Also, other additional functions of imaging can be diagnosis or treatment, or a combination of these functions, and continue to be evaluated by performing appropriate tests, including performing biopsies of internal tissue. can do. Although a specific embodiment of a capsule that includes a plurality of actuators, each associated with a different scanning device, is not shown, the scanning device disclosed herein is relatively small, so that the arrangement of such scanning devices is It will be apparent that it is possible to provide and increase the total area scanned. Each such scanning device has its own actuator and detector for detecting light from the area scanned by the scanning device, or a waveguide for transmitting the light to one or more external detectors. You will have either.

  The illumination optical system is light supplied externally from an illumination light source and a modulator as indicated by block 56. Further details regarding various preferred embodiments of external light source systems that generate RGB, UV, IR, and / or high intensity light that are transmitted to the distal end of the fiber optic system are disclosed below. Block 58 indicates that the illumination source, modulator, filter, and detector are optionally coupled to an electromechanical scanning actuator in the capsule and / or a scanning device control actuator provided in the capsule. The scanner motion detector is optionally used for scan control and generates signals that are fed back to the scanner actuator, illumination source, and modulator to perform more precise scanning if necessary.

  In block 60, image signals are filtered, buffered, scan converted, amplified, and others using electronic signals generated by the imaging photodetector and other photodetectors used for diagnostic / therapeutic and monitoring purposes. The processing function is executed. Blocks 56, 58, and 60 are interconnected bi-directionally to convey signals that facilitate the functions performed by each block. Similarly, each of these blocks is connected bi-directionally and in communication with block 62, in which analog / digital (A / D) and digital / analog (D / A) converters are provided. Process signals supplied to computer workstation user interfaces used for image acquisition and processing, related program execution, and other functions. Computer workstations can be used for mass screening of the general population, when they process images generated by scanning the esophagus so that near real-time results are provided and usually do not require evaluation by a physician Programmed to detect BE.

  Control signals from the computer workstation are fed back to block 62 and converted to analog signals suitable for controlling or operating the functions provided in blocks 56, 58, and 60. The A / D converter and the D / A converter in the block 62 are also bidirectionally connected to the block 64 and the block 66 provided with data storage. Block 66 illustrates a user interface for manipulating, positioning, and stabilizing a capsule with a scanning device within a lumen in a patient's body. Additional descriptions of various exemplary techniques for locating the capsule within the lumen are discussed below. Techniques for manipulating and locating the capsule within the lumen are discussed in further detail below. Also discussed are techniques for stabilizing the position of the capsule within the lumen.

  In block 64, the data storage is used to store images generated by the detector in the patient's body and other data related to imaging and functions performed by the scanning device in the capsule. Is done. Block 64 is also bi-directionally connected to the computer workstation and the interactive display monitor in block 70. Block 70 receives input from block 60 and enables interactive display of an image of the ROI on the inner lumen surface. In addition, one or more passive image display monitors may be included in the system as indicated at block 72. Other types of display devices, such as a head mounted display (HMD) system, may also be provided to allow medical practitioners to view the ROI in the lumen as a pseudo-stereoscopic image.

  FIG. 4 illustrates an exemplary embodiment of a scanning device 120 that can be used within a capsule. The scanning device 120 includes an electromechanical instrument or piezoceramic tube actuator 122 that causes a first mode of vibrational resonance in the cantilevered optical fiber 124. In the exemplary embodiment, the cantilevered optical fiber includes a collimator lens 126 at its distal end, and a scanning lens 128 that scans the light beam that has passed through the collimator lens, generally in the lumen. Focus directly onto the illumination plane 132 that will include the area on the inner surface. The light collected by the scanning lens 128 forms a PSF (point spread function) 134 on the illumination plane 132, and when the cantilevered optical fiber moves, the PSF 134 'moves on the illumination plane. The cantilevered optical fiber 124 can be constrained to scan along a single axis, as indicated by arrow 130, but the optical fiber can be scanned two-dimensionally, for example, in a spiral pattern. It is generally preferred to use an actuator that moves the. However, for highly amplified resonant vibrations generated by linear single-axis actuators, the resulting optical fiber motion can be two-dimensional due to nonlinear cross coupling of mechanical forces. That is, a biaxial actuator is not required for two-dimensional (2-D) scanning.

  FIG. 5 schematically illustrates the advantages of the scanning device used in the present invention. Such an optical fiber scanning device can easily implement a 120 degree FOV by imaging the scanned point source object surface on an enlarged image plane, which generally includes a region on the inner surface of the lumen. In contrast to FIG. 4 describing light beam scanning, FIG. 5 represents an exemplary embodiment of point source imaging using an imaging lens rather than a combination of microlenses and scanning lenses. FIG. 5 also illustrates, for an exemplary embodiment of an optical system 140 that includes lenses 142 and 144, the relative Gaussian beam diameter of the light used for illumination at different angles between 0 and 45 degrees. Explains. In this embodiment, the detection of reflected light is performed using a photodetector 146 located on and around the outer surface of the lens 144 (this part of the lens does not transmit illumination light), or alternatively, Light reflected from the area being scanned can also be collected and transmitted through an optical fiber to an external detector (not shown). Although shown in cross-section, the light detector 146 wraps around the entire periphery of the lens 144 and actively light both on its front surface and on all sides by its light sensitive area, which is shaded as shown. It will be understood that detection is performed automatically.

  6A and 6B describe an embodiment of a 2D scanning point source illumination device 240 and a light beam illumination device 240 'for use in a capsule. In FIG. 6A, the point source illuminator 240 can provide point source illumination through an optical fiber 242 in the capsule that scans the ROI of the lumen interior surface within the patient. When the scanning optical fiber causes the desired pattern of the provided point light source to move within a capsule (not shown), the light emitted by the scanning optical fiber passes through the imaging lenses 244a, 244b, and 244c. A plurality of points with different ROIs are illuminated. In the position illustrated by the solid line, the light beam 246 illuminates a specific portion of the ROI, while in the portion described by the dotted line, the scanning optical fiber produces a light beam 246 'that illuminates a different portion of the ROI. The light reflected from each of the series of points illuminated by the scanning optical fiber is reflected back through image lenses 244c, 244b, and 244a and received by RGB photodetectors 245r, 245g, and 245b, respectively. Corresponding electrical signals are generated and transmitted outside the patient's body and used to display a full color image of the ROI. Alternatively, the light may be transmitted through the tether to an external photodetector located outside the patient's body.

  Further, the scanning optical fiber 242 can be used to provide treatment to the inner surface of the lumen. For example, by illuminating the point scanned by the scanning optical fiber 242 with a relatively high power laser, for drug activation or PDT (photodynamic therapy), or for thermotherapy High intensity light can be applied to the ROI. Since the signals generated by the RGB photodetectors correspond to a series of points in the ROI, the images produced by the signals they generate are based on time series accumulation of pixel data. Scanning optical fiber 242 is preferably a communication grade or better single mode or hollow optical fiber. One important advantage of the present integrated system is that the mechanisms used to generate visual images are the same as those used in diagnostic, therapeutic, and surgical procedures. Directed light illumination used for image acquisition allows most advanced diagnostics and treatments to be integrated into this single imaging system within a large sized capsule that passes through a body cavity (scan engine, display And by sharing the user interface).

  FIG. 6B illustrates a scanning light beam illuminator 240 ′ for use in a capsule (not shown), including a scanning optical fiber 242 just as in the exemplary embodiment shown in FIG. 6A. Yes. However, instead of using an imaging lens, the scanning light beam illumination device 240 'uses a collimating lens 243 and a scanning lens 244' attached to the distal end of the scanning optical fiber. Light transmitted through the optical fiber 242 is collimated by the collimating lens 243 as it travels through the capsule, and then a flat illumination plane 233b or curved, depending on the ROI of the lumen internal surface within the patient. It is condensed on the illumination surface 233c. The light reflected from each of the series of points scanned as the scanning optical fiber travels returns through the scanning lens 244 'and is detected by RGB photodetectors 245r, 245g, and 245b, each on line 248. An RGB signal is provided and used to generate an image with data accumulated pixel by pixel.

  At the illumination surface, the beam of light radiation is collected to achieve the maximum intensity and / or optical quality that is the objective of all modes of scanning. When the tissue coincides with the illumination surface, the light irradiance is a function of the refractive power and the light spot size on the tissue. That is, for imaging, diagnosis, and treatment, the resolution of the scanning device placed in the capsule is determined by the size of this point in the image plane and limited by the sampling density (ie, samples per unit area of tissue). This is because higher resolution is achieved by providing more scan lines per unit area. For image acquisition, image resolution depends on the illumination spot size, detector bandwidth (and scan speed), and signal-to-noise ratio (illumination intensity and collection efficiency), but depends on physical dimensions or number of photodetectors. Is not limited.

  Since diagnosis and treatment require accurate spatial identification, there is a need to calibrate the directed illumination prior to delivery. By integrating optical imaging with diagnostic and therapeutic scans provided within the capsule, medical practitioners can easily identify the optical scan spatially by viewing the displayed image, and then the capsule is placed Can proceed to intraluminal diagnostic and therapeutic applications. Finally, the integration of computer image capture circuitry and image processing software allows image, diagnostic, and treatment data to be analyzed on a pixel basis. Since each pixel corresponds to the same area or volume of tissue, a single fiber integrated system maintains all three functions: spatial registration for imaging, diagnosis, and treatment. Consistent spatial registration from the same point of view for all three functions makes the single fiber optic scanning system provided within the capsule passing through the lumen highly accurate and easy for medical practitioners to use.

The advantages afforded by using the present scanning instrument integrated in a relatively small capsule are as follows.
Smaller dimensions by integration,
Little or no patient seedation,
No need for a doctor to insert a tethered capsule into the patient's esophagus,
Low cost due to integration and low price components
Low bending stiffness allows for better insertion into various body lumens.
If you need faster procedure times, especially repeated treatments,
Higher accuracy with integrated high-resolution imaging device and interactive display,
Additional functions with scanning optical systems, such as variable resolution (real-time zoom) and enhanced stereo effects (such as shading),
Additional functionality with integrated invisible light source and detector,
Low risk of patient infection due to multiple instruments or multiple intraluminal insertions,
There is little damage to healthy tissue, fast patient recovery time, and long-term indwelling for chronic disease monitoring.

  FIG. 6C illustrates a portion of a concentric fiber optic assembly 280 that is readily used with the capsule of the present invention for use as a confocal scanning device. The optical fiber assembly 280 includes a relatively small central optical fiber 284 that is surrounded by a cladding 286. A large diameter optical fiber surrounds a small optical fiber. ROI illumination is provided through a small diameter optical fiber 284, and the light emitted thereby illuminates the ROI through lenses 288a, 288b, and 288c. Light reflected or otherwise received from the ROI is collected by these lenses and returned into the fiber optic assembly 289, where the received light is placed outside the detector and the patient's body through the tether. It is transmitted to other devices. It should be noted that a single optical fiber can provide ROI illumination and transmission of light from the ROI to external equipment in this so-called concentric confocal imaging. Concentric fiber optic geometry is a single mechanical unit that can be melted together when hot drawn from a preform, or can concentric regions with refractive index differences by radially doping glass fibers It is. Tubular piezoelectric actuator 282 moves a plurality of concentric optical fibers together, thus scanning the ROI in one of the above modes. Light collected in the surrounding optical fiber is used with signals from detectors or optical fibers at increasing distances from the reflected confocal to enhance image analysis, diagnostics, imaging, and Improve the penetration depth of therapeutic light. For extremely high gain or discriminating detection settings, the backscattered light may be collected in the same part of the waveguide (eg, the core of the optical fiber). Such applications use optical coherent properties to amplify small signal levels and generate diagnostic maps based on optical coherent OCR (reflectometry) or OCT (optical coherent tomography) or laser excitation feedback.

  6D and 6E illustrate an embodiment of a scanning device useful within the capsule of the present invention, including detectors for RGB, UV (ultraviolet), and IR (infrared) spectral elements. The fiber optic assembly 295 includes an internal actuator 291 mounted on a carrier 293 in a capsule (not shown). An optical fiber 300 enclosed in a housing having an opening 298 extends distal to the actuator 291 and is moved by an internal actuator, preferably a tubular piezoelectric type, to achieve a desired scanning pattern, such as a spiral or spiral scan. . As illustrated in FIG. 6E, RGB detectors 292 and 294 are disposed above and below the optical fiber 300, while RGB detectors 306 and 308 are disposed on the left and right of the optical fiber. Further, as shown in these figures, RGB detectors 290 and 296 are located on the outer surface of the assembly, at the top and bottom thereof. In a similar manner, RGB detectors 302 and 304 are attached to the left and right sides of the detector as described in FIG. 6E. UV detectors 310 and 312 are mounted on one diagonal of the RGB detector, while IR detectors 314 and 316 are mounted on the other diagonal. Thus, when imaging tissue on the inner surface of the lumen from within the capsule of the present invention, a pseudo-stereoscopic image for RGB, UV, or IR spectral elements received by the various detectors included on this assembly. Is generated. By comparing the signals from complex RGB detectors and knowing the orientation of the tethered capsule in the lumen, the level of the signal due to specular reflection and complex dispersion is estimated and reduced by appropriate signal processing be able to.

  FIGS. 6F and 6G illustrate a fiber assembly 295 ', in which parallel and light beam detectors are included. The optical fiber 300 transmits light deflected in a parallel direction, as indicated by reference numeral 328. As shown in FIG. 6G, parallel deflected light detectors 334 and 336 are disposed on opposite side surfaces of the optical fiber 300, while direct deflected light detectors 324 and 326 are disposed above and below the optical fiber 300. Further, the orthogonal deflection light detectors 320 and 322 are disposed above and below the orthogonal deflection light detectors 324 and 326, while the parallel deflection light detectors 329 and 330 are disposed on the left and right of the parallel deflection light detectors 334 and 336. . That is, the fiber optic assembly 295 ′ is useful for detecting bi-directional deflected light within the capsule and is positioned outside the patient's body and receives instrument output signals through a tether coupled to the capsule ( For analysis by (not shown in these figures), light is reflected or received from the ROI on the inner surface of the lumen. The signals generated by the various deflection photodetectors can be used to generate an image of the tissue inside the lumen for external display corresponding to a particular type of deflection. By recording light that is shifted in deflection by interaction with tissue, specular reflection is minimized. Since the degree of deflection from the tissue depends in part on the optical properties of the tissue, various tissue types and depths can be identified by measuring both axes of deflection.

  FIG. 7A aimed at both providing a pseudo-stereoscopic image of the ROI on the inner surface of the lumen and acquiring a spectral image that can be analyzed using a spectrophotometer outside the lumen. An exemplary scanning and detection system 266 that can be used with a capsule is described. In this system, an optical fiber assembly 250 comprising a tether that extends through a lumen and out of a patient's body includes an optical fiber 256 that is tapered at the distal end and surrounded by a piezoelectric actuator 254. Actuator 254 causes optical fiber 256 to vibrate and scan for ROI, causing the emitted light passing through lenses 258a and 258b to illuminate the interior surface of the lumen (not shown). Light reflected from the tissue ROI or otherwise received from it (such as phosphorescence or fluorescence) is transmitted by twelve optical fibers 252 arranged in a circumferential array around the optical fiber 256. Focused. As described in this exemplary embodiment, optical fibers 1, 2, and 3 collectively referred to by reference numeral 260 are external RGB corresponding to the left side of the circumferential array, each through a tether. Coupled to the imaging detector. Similarly, optical fibers 7, 8, and 9 collectively referred to by reference numeral 262 are each coupled through a tether to an external RGB imaging detector on the right side of the circumferential array. Another set of optical fibers 264 is coupled to the spectrophotometer 270 through a tether. Spectrophotometers are used for spectral analysis and spectral image acquisition using UV, visible, and / or IR light. Since the RGB detectors on the left and right sides of the circumferential array receive light from the ROI in two spaced apart parts of the array (ie, the left and right sides), they are easily viewed using an HMD display (not shown) A pseudo-stereo full color image that can be generated is generated.

  A schematic diagram illustrating an exemplary light source system 340 for generating light of different spectral configurations that is coupled through a tether into an optical fiber 360 disposed within the capsule is illustrated in FIG. 7B. In this embodiment, a red light source 342, a green light source 344, a blue light source 346, and a UV light source 348 are each selectively coupled to the optical fiber 360. The optical fiber 360 passes through the tether so that the distal end of the optical fiber emits light and the capsule containing the distal end of the optical fiber illuminates tissue on the inner surface of the lumen through which it passes. Extend. An attenuator 350 is provided at the proximal end of the optical fiber for each light source so that the intensity of the light generated by the light source is selectively controlled. Three dichroic mirrors 352, 354, and 356 containing coatings specific to the color of the light emitted by each of the corresponding green, blue, and UV light sources are positioned in the optical path to provide green, blue, and UV Each of the light reflects into the proximal end of the optical fiber 360. Light outside the respective reflection wavelength bands of these dichroic mirrors passes through the dichroic mirror and is collected by the lens 358 into the proximal end of the optical fiber 360.

  An alternative light source system 362 for use with the present invention is illustrated in FIG. 7C. In this embodiment, red, green, and blue light sources 342, 344, and 346 are coupled to a series or continuous optical coupler 366, through optional attenuator 350, through lens 364, respectively. Yes. The lens 364 collects light from each of the light sources of different colors into the optical fiber 365 and transmits the light to the optical coupler 366. Further, the IR light source 368 transmits light through the optional attenuator 350 and lens 364 and into the optical fiber 365, which in turn transmits the IR light to the final optical coupler. A photodetector 369 is provided to monitor the respective light intensity levels or power levels of the different light sources, allowing the intensity of the various light sources to be controlled. From the final optical coupler, an optical fiber 367 transmits light to the input of the photodetector 369, while the output of the final optical coupler is to a scanning device placed in a capsule within the lumen of the patient. as input, and are inputted to the proximal end of the optical fiber 360 (the tether or capsules containing optical fiber 360, both for ease of illustration not shown).

  As indicated above, the development of a relatively low-cost, mass-manufacturable scanning device with a small cross-sectional area ensures the endoscopic capsule scanning system is economical and thereby promotes the spread of use It is desirable. When manufacturing economical scanning devices, this objective can be more easily realized by making effective use of MEMS (microelectromechanical system) technology using integrated thin film equipment. FIGS. 8A, 8B, and 8C illustrate an exemplary thin film optical system 370 that can be adapted for use as a scanning device in a capsule for use in scanning applications. An additional exemplary alternative 370 'described in FIG. 8D includes a parallel cantilevered thin film optical waveguide for scanning and detector.

  In the exemplary embodiment of this thin film scanning device, an electrostatic actuator 386 operates on a thin film optical waveguide 380 carried on a raised ledge 378. Thin film optical waveguides are only about 0.003 mm in diameter. The distal portion 382 of the thin film optical waveguide is caused to scan in two orthogonal directions indicated by the curved arrows in FIGS. 8A and 8B. Note that the scanning motion can be one-dimensional (ie, along a single axis) or, as shown, can be two-dimensional (eg, according to either a raster pattern or a spiral pattern). . Optionally, the thin film optical instrument can be mounted on a rod 373 in the capsule and can be rotated or vibrated manually or mechanically to change direction or displace a single axis scan. Also provided is a lens 384 that can be attached to a silicon substrate 376 (or other substrate material). Alternatively, an actuator (not shown) that is external to the substrate but statically placed in the capsule can be used in place of the electrostatic actuator, in which case the optical fiber 374 and lens 384 are carried by the silicon substrate 376. It will be. The optical fiber is caused to vibrate by an external actuator, causing a desired pattern of resonant scanning in the cantilevered thin film optical waveguide.

The optical fiber 374 can be mounted within a centering V-cut 390 in the silicon substrate 376 to ensure that the optical fiber is aligned with the thin film optical waveguide 380. Since the optical fiber is approximately 0.1 mm in diameter, care must be taken to accurately align the end of the optical fiber and the thin film optical waveguide. FIGS. 8A and 8B show an exemplary embodiment using a butt-end coupling between the optical fiber 374 and the thin film optical waveguide 380. To ensure proper alignment between the optical fiber and the thin film optical waveguide, a V-cut 390 provides a relative placement of the optical fiber with respect to the thin film optical waveguide. Refractive index matching gel 375 or liquid can be used to couple optical fiber 374 to thin film optical waveguide 380. In order to reduce the gap filled with the refractive index matching gel 375, the tip of the optical fiber can be etched into a tapered shape. In addition, the length and surface of the tip can be adjusted by CO ₂ laser machining prior to attachment. Other embodiments of the MEMS scanning device described below further reduce the alignment problem.

In the embodiment shown in FIGS. 8A, 8B, and 8B, light reflected from the target in the ROI passes through lens 384 and is received by RGB detectors 392r, 392g, and 392b, respectively. These detectors located within the capsule are responsive to the corresponding color light and, as described above, produce a signal that is transmitted proximal to the external component. In FIG. 8D, separate images and diagnostic / therapeutic thin film optical waveguides are spaced apart and scanned in parallel. This exemplary embodiment uses a diagnostic “DIAG” detector 392d.
Automated system for mass screening

  One intended use of the present invention is to screen a BE patient (manually performed by a physician), allowing the present invention to ultimately perform a substantially automated esophageal screening process by a medical practitioner. Don't need that). FIG. 9 is used in conjunction with the present invention to perform a scan of the esophageal interior surface of patient 395 by medical practitioner 408 to determine if the patient suffers from BE (or some other condition of the esophagus). It describes an automated system. The system includes a computer processor 394 that performs many of the above functions in conjunction with FIG. 3 and in the following additional details.

  The tether 22 is connected to the computer processor 394 after passing through a non-contact axial motion measurement device 396 that is used to monitor the movement of the tether 22. As described above, the tether 22 is used to retract or advance the capsule within the esophagus of the patient 395. An electrical cable 402 communicates a signal generated by the non-contact axial motion measurement device 396 indicating the tether position or axial movement to the computer processor 394. A tether 22 that includes one or more optical fibers and one or more conductors that carry optical and electrical signals to and from a scanning device disposed within a capsule (not shown in the figure). It can be stored with the capsule or advanced in the esophagus. The tether extends between the lips 404 and down the patient's esophagus. A sign (eg, magnetic or optical as described in detail below) causes the position and movement of the tether to be detected as the tether passes through the device 396. Patient 395 is initially given a liquid, such as water, in cup 406 to facilitate swallowing of the capsule and attached tether 22. The liquid is swallowed after the capsule is inserted into the patient's oral cavity, helping the capsule to advance through the esophagus by normal peristalsis of muscles including the esophageal wall as the patient swallows the liquid.

  The capsule is left to advance into the patient's stomach and then withdrawn through the LES by the medical practitioner 408 who grasps the handle 402 and rotates the reel 396. Computer controlled capsule removal can be fully automated by using a motor driven reel (not shown) to remove the capsule over the esophagus. That is, the computer responds to the criteria for determining the quality and content of the image being scanned by the capsule in real time and in response to the signal output from the non-contact axial motion measurement device 396 how fast the capsule is. You can decide whether to remove. In addition to controlling the removal speed of the capsule, the computer can control the intensity of the light provided for the scan and patient specific variables, perform automatic image stitching and length of the lumen A panoramic image of the internal surface along the line can be formed. An example of currently available automatic image stitching software is disclosed (see, for example, Non-Patent Document 1). Such images can be used in conjunction with image recognition software to determine the location of the LES and to automate the determination of whether the patient has BE or some other medical problem. Also, as an alternative instrument to calibrate images that have been automatically stitched together to form a complete 360 degree panoramic field to clarify the position of the capsule in the patient's esophagus, the length of the capsule from the LES A measuring device such as a ruler in pixel units can be formed. As an additional alternative, the signal generated by the non-contact axial motion measurement device 396 is used to speed up the process of stitching together successive axial images of a lumen such as the esophagus, resulting in a complete continuous panoramic view of the lumen. An image can be formed.

  By looking at the display 398 connected to the computer processor 394, the medical practitioner can easily observe the stomach image, and then when the reel winds up the tether and retracts the tether on top of the LES, A medical practitioner can observe an image of the inner surface of the esophagus on a display. A display 400b is displayed on one of the displays to indicate the relative speed and position at which the capsule moves through the esophagus.

The computer processor 394 can detect the LES based on changes in the image 399, display the capsule distance 400a from the LES, and automatically evaluate the image of the internal surface of the esophagus directly above the LES. It can be programmed to determine if the patient has a characteristic dark pink color indicating BE. The results of the image scanning process are thus fully automated so that esophageal conditions can be detected in real time and immediately indicate whether the patient is suffering from BE, so that the medical practitioner can scan the tether 22, And it should only be required to assist the patient during the initial swallowing of the capsule. The efficiency of such a system will allow mass screening of the general population to be performed with minimal expense, and esophageal cancer, where BE is often a precursor, will be avoided by early detection of BE.
Functional block diagram

  FIG. 10 illustrates at least some of the various functions that can be performed by an exemplary scanning system when a capsule is placed in a lumen of a patient's body. Functions such as diagnosis, treatment, and monitoring are shown in blocks formed by dotted lines, while the solid lines are used for the imaging function of system 410 that is performed with the capsule and associated components. As shown, the imaging laser 412 is directed by the scanning device within the capsule through the imaging optics that is directed through the tether into the patient's body and used with the scanning optical fiber disposed within the capsule. Generate light to be attached. In addition, the diagnostic, therapeutic, and monitoring lasers in block 416 controlled by the remote light switch and attenuator in block 418 generate coherent light that passes through the optical coupling mechanism 420 to the lumen in the patient's body. Transmitted to an additional optical component 422 located within the capsule used therein. The RGB photodetector 430 is responsive to light received from the ROI on the interior surface of the lumen and generates an electrical signal that passes through or in parallel with the conductor in the tether and is external to the patient. Is transmitted to the devices arranged in Alternatively, the RGB light is transmitted through an optical fiber in the tether to an external photodetector 426 outside the body, or to other types of photodetectors 424 including, for example, photodiodes and associated circuitry.

  As shown in box 432, an additional high or low power UV and / or visible light detector associated with a collection fiber for use by one or more spectrophotometers or spectrum analyzers and An exemplary system may include / or an IR photodetector. For example, the spectrophotometer and spectrum analyzer shown at block 434 can receive light transmitted through the collection optical fiber and / or a signal transmitted over the electrical conductor shown at block 436. The system may optionally include an additional photodetector located within a capsule within the patient's body. Signals are exchanged bi-directionally between blocks 432 and 434, the computer processor (or workstation), and the data acquisition components in block 440. The computer processor can execute and control algorithms that provide non-linear scan patterns and can also be programmed to perform intensity data acquisition, image mapping, panoramic image stitching, and data storage. . In addition, real-time filtering (eg, correction of motion and scanner artifacts), real-time ratio determination and background removal, analysis, pseudo-stereo enhancement, and processing of signals generated by various detectors are performed by a computer processor. . The signal supplied by the computer processor is output to a data storage on an image display device (as shown in FIG. 9) and a non-volatile storage (not shown). The image display device can include a cathode ray tube, a liquid crystal display, and an HMD device, or other type of stereoscopic image display, as described in block 442.

  Since commercially available displays generally require a linear video format, any non-linear optical scan pattern is stored in a data buffer (memory) and converted to a standard raster scan format for display monitoring and contained in an exemplary capsule. Many of the advantages of non-linear scanning used in one or more scanners (such as simple single actuator, cylindrical scanner dimensions, and low scanning speed) must be utilized. This additional step in signal conditioning and mapping is technically trivial with programmable computing equipment.

  In addition, image analysis software that performs spectral analysis and multivariate analysis to locate and calculate the boundaries of the region of interest is executed using a computer processor or other computing device. For the ROI on the inner surface of the lumen, the calculation results can determine its range, boundary, volume, color, and absorbance, and based on data collected from the ROI, a tissue disease state such as BE, and In addition to determining stage, treatment doses can be calculated and monitored. All these functions are shown in block 444, and a conventional imaging computer processor in block 440 can be used. Block 444 is connected to block 446 where an additional interactive display and image overlay format is provided. Associated with block 444 is block 448, which provides scanning device power and control circuitry for operating the electromechanical scanning device and receiving signals from the servo sensors in block 450, which provide screening, monitoring, and It has been shown to be used for both diagnosis and normal image acquisition and enhancement involving the delivery of pixel-level accurate therapy to a desired site within a lumen.

  Embodiments of fiber optic scanning actuators have been described so far in connection with moving a scanning device disposed within a capsule to image an ROI in a lumen. Block 454 is prepared to manually control the distal end of the scanning optical fiber so that the capsule containing the scanning optical fiber is inserted into the patient and positioned at a desired location near the ROI. Is shown. Manual control will likely include rotating the capsule with a tether orientation and / or axially positioning the capsule and scanning device relative to the ROI in the lumen; As indicated at block 456, an automatic servo sensor may be used to facilitate positioning the capsule and one or more scanning devices to a desired position. Once positioned, automatic vibration compensation for the scanning device is provided to stabilize the image against biological motion (breathing and heart motion) and physical patient motion, as described in block 452. In addition, other mechanisms can be provided in at least one exemplary embodiment to stabilize the capsule in a desired location within the lumen of the patient's body.

Details of various functions that can be executed by the capsule imaging system are as follows.
Integrated imaging, screening and diagnosis Optical tissue imaging using UV, visible and IR wavelengths,
Fluorescent tissue imaging using UV, visible, and IR wavelengths,
Thermal imaging using IR wavelengths,
Deep tissue imaging using IR wavelengths,
Concentric confocal imaging and true confocal imaging,
Blood transmission imaging using IR wavelengths,
Deflection contrast imaging,
Laser feedback microscopy,
OCT (optical coherent tomography) and OCR (reflectance measurement),
Optical pseudo-vibration acoustic analysis,
High resolution enlarged tissue contact imaging,
LIF (laser excited fluorescence) imaging and fluorescence ratio imaging and detection,
Multiphoton excitation fluorescence imaging,
Fluorescence lifetime imaging and analysis,
Full-scale reproduction of imaging structure using 3D and distance measurement options,
LIFS (laser excitation fluorescence spectroscopy),
Raman spectroscopy,
ESS (elastic scattering spectroscopy) analysis,
Absorption spectroscopy,
Chemiluminescence and cell viability detection and mapping,
Spatial mapping of optical sensor data (oxygen concentration, pH, ion concentration, etc.),
Temperature measurement and feedback control,
Color, laser power supply, tissue for pressure measurement (pressure measurement) and guidance of correlation between visual observation and pressure detection findings of the esophagus, lower esophageal sphincter, stomach, pylorus, small intestine and other body cavities, and monitoring and feedback control Other measurements such as properties, photobleaching, complex color development,
Treatment, surgery, and monitoring PTD (light therapy),
Heating the tissue and / or tumor (eg hyperthermia),
Laser surgery with light illumination (UV, heat and / or ablation),
Photoactivation analysis, photopolymerization, and biomaterial transplantation,
Mechanical destruction of tissue using laser ablation and shock waves generated by absorption of optical pulsed radiation.
Interactive interactive display and advanced user interface design Pseudo-stereoscopic on display monitor, stereoscopic image mapping using pseudo-color overlay, and true 3D display format (Note, individual display methods and capabilities are specific to specific applications) Dependent), and interactive touch / point screen.

  11A and 11B illustrate various functions that can be performed by the capsule, depending on the equipment used in the scanning system. FIG. 11A shows a single scanning waveguide used to perform imaging, sampling diagnostics, and treatment, while in FIG. 11B the single scanning waveguide is 3D imaging, biopsy tissue sampling, endoscopy Used to monitor mirror surgery. In these two figures, it is useful to recognize that many of the same components are provided and that different functionality is provided by making minor changes to the components used as part of the system. is there. In the system 460 shown in FIG. 11A, the interactive computer workstation monitor 462 allows the medical practitioner to control the scanning optical fiber to be used for imaging, diagnosis (eg, optical biopsy), and performing the therapy. It becomes possible to execute the algorithm. High resolution color monitor 464 receives signals from scanning optical fiber 484 transmitted over optical fiber system 488 to distribution console 472. An optional RGB detector can be provided if not internally contained within the patient near the scanning optical fiber 484. The ROI 486 is scanned by an optical fiber to produce a high resolution color image that is displayed to the user. In one embodiment of an exemplary passive display, two CRT (CRT monitor) displays display images using two different contrast modes to generate images of the same object (eg, tissue). For example, the same resonant drive scanning optical fiber can generate both a full color optical image on a CRT and a grayscale fluorescent image on another CRT monitor. If there is no overlap in excitation and signal optical properties, two or more images can be generated simultaneously. In the case of overlap, the two images are stored either by the surface sequential method or the line sequential method of the fast resonant scanning device. To switch between image contrast modes (full color optics and fluorescence), close the shutter of the light source or turn the power off and on directly. In time synchronization during modulation of both illumination intensity and spectral range, the signal from the photodetector is recorded and displayed as a separate image. In this example, a second fluorescent image of the same ROI can be obtained to ensure that the medical practitioner identifies small or pre-cancerous lesions that are not visible on a standard white light image.

  One of the two indicators is, for example, by using a touch screen monitor or an interactive foot mouse or pedal that allows the medical practitioner to select (outline) the ROI for laser surgery. It is intended to be interactive. Since the image may be moving, the touch screen monitor requires the image to be saved and stopped at the same time. However, once the ROI outline is drawn, image segmentation and subject recognition algorithms are executed to keep the ROI highlighted during real-time image acquisition and display. The interactive monitor may provide a practitioner sidebar menu for setting parameters for laser therapy, such as power level and duration of laser radiation exposure. The second display will not be used interactively, but a high resolution monitor that displays real-time optical images in full color or gray scale is preferred. When the IR photodetector is integrated into the endoscope, the practitioner monitors the progress of the tissue laser treatment, such as tissue heating and / or tissue emission during laser surgery, with a high resolution display with pseudo colors Will be able to.

The scanning optical fiber in the capsule is positioned in the desired position in the patient opposite the ROI 486 using a tether and an optional manual controller that facilitates steering and stabilization of the tip, as shown in block 466. Is positioned. The placement of the capsule in the lumen is based on the position sensor signal or the tether extends into the lumen by referring to a scale provided on the tether as discussed below in connection with FIG. It is determined automatically by simply monitoring the distance. Within ROI 486, the optical biopsy “location” 485 describes the spatio-temporal distribution of single point spectroscopic measurements for diagnosing disease. These locations are distributed in large numbers according to current practice of taking tissue samples invasively for in vitro biopsy analysis. Each location is analyzed spectroscopically during the frame cycle of the optical scanner, with t ₁ and t ₂ separated by, for example, about 1/30 second. In addition to the image provided by the scanning optical fiber, an IR temperature photodetector (and optional temperature monitor) may be included to receive the IR signal from the ROI, as shown in block 468.

  To facilitate operation control of the scanning optical fiber or optical waveguide, a small sensor power and control circuit is provided, as shown in block 470. The signal provided by the control circuit allows optical fiber amplitude and displacement control when the actuator that causes the optical fiber scan is controlled by both electrical hardware and software in block 470. A spectrophotometer and / or spectrum analyzer 474 is included for diagnostic purposes because the spectral components of the light received from R0I 486 and the distribution of the optical biopsy site 485 can be determined based on spectral photometric analysis. This is because it can be used for screening and diagnosis of diseases such as cancer by medical practitioners who evaluate the condition. To illuminate the ROI so that the ROI is imaged, the red, green, and blue light sources 476, 478, and 480 are combined and the light they generate is scanned through the fiber optic system into the capsule. It is transmitted to the optical fiber 484. The light source used for spectral analysis may be one high power pulse of an external RGB light source (eg, a laser), a second laser or a white light source. Since signal strength, time, and illumination intensity are limited, an iterative one-point spectral analysis method will be used first using flash illumination. In addition, the same or another high power laser light source 482 may be used to treat PTDs, laser ablation of dysplasia, neoplasia, and tumors, and other types of treatment provided using high intensity light sources, etc. Can be implemented.

  When using the system 460, the medical practitioner looks at a high-resolution color monitor displaying standard full-color endoscopic images while attaching a soft tether and an attached capsule containing a scanning device to the appropriate area of the patient's body lumen. Maneuver and operate. Exploration of intraluminal tumors, neoplasia, and / or precancerous lesions can be initiated by simply looking at the monitor. A second monitor (not separately shown) included in the spectrophotometer and spectrum analyzer 474 displays a pseudo-color fluorescence mapping on the grayscale image generated by the scanning device in the capsule. If tissue with an abnormal appearance is found, the capsule is optionally mechanically stabilized (eg, by inflating an attached balloon, as described below). The ROI on the lumen wall is centered within the scanning device FOV and then magnified using the multi-resolution capabilities provided by the scanning device. ROI or cancer dimensions are evaluated, and pixel boundaries are determined by image processing of either visible or fluorescent images. If spectroscopic diagnosis is required, such as LIFS, the distribution of optical biopsy points is estimated along with the illumination level. Diagnostic measurements are made by automatically and repeatedly providing illumination on multiple imaging frames. The user can interrupt the diagnosis or the signal to noise ratio and / or sampling density at the workstation until a clear diagnosis can be made from the generated image of the lumen internal surface by the scanning device in the capsule. Can continue to improve. The result of diagnosis is expected to be superimposed on a standard image in real time.

  When optical therapy is approved, such as PDT, optical radiation exposure is determined and programmed into an interactive computer workstation that controls the scanning device system within the capsule. A PTD procedure is generally an optical scan of high intensity laser illumination with a high power laser light source 482 preselected for PDT fluorescence staining, and includes a dichroic filter, attenuator, and electromechanical shutter as described above. Controlled using. In the frame sequential method, both the fluorescence image and the visible light image are acquired during a PDT treatment provided using a scanning device in the capsule. The medical practitioner monitors the progress of the PDT treatment by viewing these images acquired by the scanning device on both displays.

  Referring to FIG. 11B, the scanning system 460 ′ provided in the capsule is used for 3D imaging, biopsy, and endoscopic surgery monitoring of the lumen internal surface. An HMD 490 is included to enable 3D imaging of the ROI pseudo-stereoscopic field of view. In addition, the system includes the high resolution color monitor 464 described above in connection with FIG. 11A. An IR optical phase detector 492 is also included for distance measurement within the lumen. The high frequency modulation of IR illumination is measured to determine the phase shift due to the optical propagation distance on the order of a few millimeters. The distance between the distal end of the scanning optical fiber or optical waveguide in the capsule and the ROI 486 is important for evaluating the intensity of the light, and for specific ROI 487 mapping to determine ROI boundaries and dimensions In addition, this light intensity should be applied during endoscopic surgery to determine the size and shape of features such as dysplastic regions or tumor volumes, including intraluminal ROI. UV-visible biopsy light source 494 allows optical biopsy to be performed with a specific ROI 487. The spectrophotometer and spectrum analyzer in block 474 are useful for monitoring the status of the ROI during the endoscopic procedure being performed because the status of the ROI during the endoscopic procedure is This is because it is sometimes best determined based on the spectral analysis provided by this instrument. In other respects, the components used for the alternative function provided in FIG. 11B are the same as those in FIG. 11A.

  When using system 460 ', the medical practitioner moves the tether and capsule while viewing the high resolution color monitor 464 showing a visible wavelength (full color) image to reposition the scanning device and look for new tissue again. Once the ROI is found, the capsule can be mechanically stabilized, for example, by inflating the attached balloon, as described below. In addition, the ROI is centered in the FOV and then magnified by the multi-resolution function. However, if the surrounding tissue is moving and the acquired image is not stable, a snapshot of the image is taken and transferred to an interactive computer workstation monitor, preferably a bi-directional display. A stable ROI boundary outline is drawn on the screen of the interactive display and the dysplasia area or tumor volume is measured using a pixel-by-pixel diameter and distance measuring IR optical phase detector 492. Estimated from distance measurements between device and tissue. The optical biopsy is performed by a UV-visible biopsy light source 494, but may be a fiber coupled arc lamp for ESS (elastic scattering spectroscopy). If this tissue is indeed cancerous or pre-cancerous, the optical radiation exposure is calculated and the treatment protocol is programmed into the interactive computer workstation monitor 462. The digital image processing algorithm is calibrated to automatically segment the ROI or process the scanner signal to estimate motion artifacts from images acquired in real time, which is equivalent to or slower than the display frame rate. Laser surgical procedures and / or ablation occur with a high intensity laser 482 (IR) that is optically coupled to a visible optical scanning device. If an IR distance measurement option is not required but an IR temperature monitor or laser monitor is desired, an IR light source can be used instead for these alternative monitoring functions. For frame sequential methods, both IR and visible images are required during laser surgery and / or cauterization. The IR image is either a mapping of backscatter from the laser illumination as the laser illumination scans the intraluminal ROI, or a temperature image of the ROI, and a pseudo color on a grayscale visible image on an interactive computer display. Can be displayed as The medical practitioner monitors the progress of the IR radiation procedure by observing these acquired images on both the high resolution and interactive display monitors.

Determining Capsule Placement in a Body Cavity The previous exemplary embodiment of a scanning flexible endoscope uses a wheel when the tether is manipulated to control the position of the capsule in the patient's esophagus Rotated with the axial movement of the tether. However, using this type of contact sensor does not accurately report the position of the capsule in the esophagus because the presence of saliva, mucus, or other bodily fluid slides the tether over the rotating sensor wheel. Further, the requirement to maintain friction between the tether and the rotation sensor wheel may interfere with the “feel” that medical personnel may want to experience when controlling a tethered capsule. Accordingly, FIGS. 12 and 13 illustrate two alternative exemplary embodiments of a non-contact sensor for measuring the relative placement of capsules in a body cavity such as the esophagus.

  In FIG. 12, the proximal end of tether 630 is illustrated outside the oral cavity of patient 636. Although not shown in this view (or FIG. 13), the distal end of tether 630 extends down into the esophagus of patient 636. An optical marker 634 is axially disposed along at least a portion of the tether 630 and, depending on the form of the marker, provides an analog or digital indication of the relative placement of the tether within the esophagus of the patient 636 and thus the relative placement of the capsule. Can be provided. A display of an exemplary analog optical pattern 680 is illustrated in FIG. 20A, while FIG. 20B illustrates a display of an exemplary digital optical pattern 682.

  One skilled in the art will appreciate that many light sensors can be readily used to read either analog or digital encoded data provided on a label on the tether. For example, a light source (not shown separately) on the light sensor 638 can be directed toward the sign 634. Alternatively, ambient light can be used to illuminate the sign. The light reflected or scattered by the sign on tether 630 is received by light sensor 638 and includes a photodiode or other suitable photodetector, but is not separately illustrated in this figure. Also, one or more lenses can be included in the light sensor to focus the light source (if used) on the sign and / or to focus the received light on the photodetector. Since the light source can be directed to pass light through the sign, it is also intended to receive the transmitted light by a photodetector on the side of the sign opposite the light source. However, this method is unlikely to be implemented due to problems associated with the transmission of light through the tether perimeter and is not shown in the figure.

  The optical sensor can use ultraviolet light, visible light, or infrared light from a light emitting diode (or other suitable light source) and uses an optical fiber (not shown) to direct the light Can be transmitted from the light source to the sign on the tether. Similarly, other optical fibers (not shown) can be used to collect the light from the sign and transmit it to the photodetector. By using a shorter wavelength light and a lens with a larger numerical aperture for the collection optical fiber, the spatial resolution at which the sign is read on the tether can be improved. The sign can be applied axially around the entire circumference of at least a portion of the tether so that the orientation of the tether does not care about the direction of rotation about its longitudinal axis and the sign can be read by an optical detector Can do.

  In FIG. 13, indicia on tether 630 includes a magnetic medium 642, such as magnetic paint or tape, and is applied along at least a portion of its length along the longitudinal axis of the tether. When detected or read by the magnetic sensor 640, the magnetic medium can store a varying magnetic field that represents the relative position of either analog or digital data, ie, the position of the capsule in a body cavity such as the esophagus. The magnetic sensor 640 can include a high sensitivity magnetic pickup coil (not separately shown) such as those used in tape recorder heads. Magnetic media encode position data as analog or digital data using variable magnetic strength, modulation, frequency, or a combination of these types of encodings. Since the magnetic encoding can be read by a magnetic sensor, its signal can be used to indicate the relative position of the capsule in a visual indicator as well as to indicate the relative position of the capsule in the body cavity. It is intended to provide an audible sound.

  The relative position of the tether and capsule within the body cavity is important for a variety of reasons. First, the medical practitioner can correlate the apparent internal surface condition of the body cavity with the position of the capsule within the body cavity in the image generated by the image scanning device contained within the capsule. You can clearly see the state of BE at the specific location. This information can be used to continue approaching the same location within the body cavity to provide further diagnostic procedures or treatment. FIG. 14 illustrates how a non-contact position sensor 646 (such as the optical or magnetic sensor of FIGS. 12 and 13) reads a sign on the tether 652 and generates a position signal that is input to the processor in the SFE base unit 394. Explains what to do. A position determination function 648 is executed by the processor to always determine at least the relative position of the capsule 650 within the body cavity. At the same time, the capsule uses the image scanning device to generate an image signal that is input to an image generation function 662 that is executed by a processor in the SFE master. The relative position of the capsule not only allows the current image position generated by the scanning device in the capsule to be indexed, but also assists the processor in the SFE master that performs the stitch mosaic image generation function 664. Thus, it is also used to bind a series of axial images more efficiently. Even without the relative position data provided by the non-contact position sensor 646, these series of axial images can be stitched together, but the relative position data can be stitched anywhere along the longitudinal end of the series of images. To reduce the processing time for determining whether to create an axially continuous mosaic image showing the internal surface of the body cavity along most of the length of the body cavity.

  The data provided by the position determination function 648 may indicate the actual distance that the capsule has moved somewhere from the reference position to the next position. For example, the reference position of the capsule corresponding to the placement of the capsule at the gastroesophageal junction is determined from the image generated by the capsule, and the subsequent movement up the capsule esophagus is a signal generated by the non-contact position sensor 646. Can be used to represent the actual distance from the reference position. That is, once this reference position is determined, the distance from the reference position to the region on the inner surface of the esophagus where the BE state is clearly observed in the image is determined from the position data. This region can be easily found again by repeating the steps of setting a reference and advancing the capsule above the same distance.

  Optionally, when removed from a body cavity or esophagus, it is desirable to gently clean bodily fluids such as saliva and mucus in the tether 652 before bodily fluids on the tether reach the non-contact position sensor 646. As illustrated in FIG. 15, an elastic cone 670 or other type of scraper that fits snugly into the tether 652 can wipe the bodily fluid 672 from the outer surface of the tether, which can be Does not add any significant friction that interferes with the tether movement through the body cavity. Body fluid can easily fall onto an absorbent material or sponge (not shown), i.e., when drops 674 fall from the lower peripheral edge of the elastic cone, they collect in a small dish (also not shown). be able to.

Use of a Balloon Coupled to a Capsule FIG. 16 illustrates a capsule 570 having an inflatable balloon 574 coupled to the proximal end of the capsule. The balloon does not interfere with the illumination light 572 that is directed from the distal end of the capsule to the inner surface 582 of the lumen in which the capsule is located. The volume 586 in the balloon 574 is selectively inflated by liquid or air carried through the lumen 578 in the tether 576. Liquid is present in lumen 578 through at least one opening 588 formed in the portion surrounded by the tether balloon.

  The balloon can be inflated to serve one or more of the following notable purposes. For example, since balloon 574 can inflate, the peristaltic movement of muscle tissue causes the balloon and capsule to advance through the lumen, and the larger diameter of the balloon causes the force applied by the muscle tissue to The connected capsule is advanced more efficiently in the lumen. As an additional option, when the balloon is inflated, the pressure from the lumen wall in which it is placed can be communicated to a pressure sensor (not shown here but discussed above), Because it is on the capsule or in fluid communication with the internal volume 586, the pressure exerted by the lumen wall can be monitored external to the lumen. Various conditions can be determined by pressure, i.e. providing information of interest to the physician.

  Instead of allowing the capsule to advance, the balloon is at least partially inflated to enlarge the cross-sectional dimension of the balloon so that the capsule passes through a lumen portion or other passage having a smaller cross-sectional dimension than the balloon. Further movement can be prevented. Finally, the balloon is inflated so that the capsule can be centered and stabilized approximately within the lumen of the patient's body so that the inner surface scan to generate an image is performed more efficiently. .

Electrical contacts for stimulating peristalsis A capsule 590 is illustrated in lumen 592 of FIG. 17 and includes a plurality of electrical contacts 594 disposed on the outer surface of the capsule housing. The electrical contact 594 is connected to a lead 598 that extends through a passage 602 formed in the tether 600. The lead wire is connected to a power source (not shown). A voltage is thereby selectively applied through lead 598 to electrical contact 594, thereby contacting muscle tissue 604 and stimulating peristalsis within the muscle tissue of lumen 592, which causes the capsule to pass through the lumen. Advance through. Optionally, electrical contacts 596 connected to tether 600 proximal to capsule 590 can be used in place of or in addition to electrical contacts 594 to stimulate muscle tissue peristalsis.
Mechanical biopsy

  FIG. 18 illustrates a capsule 620 that is coupled to a tether 624. The tether 624 includes an annular passage 622 in which one or more cytological brushes 626 or biopsy forceps (not shown) are controllably advanced so that the inner surface of the lumen in which the capsule 620 is disposed. To touch. The cytodiagnosis brush 626 is advanced from the annular passage 622 to contact tissue on the inner surface, so that tissue cells that line the lumen are transferred to the brush hair. The cytology brush is then withdrawn into the annular passage and after the capsule and tether have been withdrawn from the lumen within the patient, the cell sample is removed from the brush hair for processing and investigation. Although not shown, an annular passage can be used to pull back the lid on the capsule, which exposes the bristles of the brush that are advanced from the capsule. Instead of an annular passage, a cytological brush, fine needle, or other type of mechanical biopsy device can be advanced through a shoulder passage (not shown) provided on the tether. A gripping device can also be used in the annular or shoulder passage to collect the sample from the lumen and retract the sample into the passage. Such a passage can also be used as a liquid intake, where the liquid is drawn through the passage to the proximal end of the tether outside the patient's body.

Composite Image As mentioned above, it is contemplated that a plurality of scanning devices can be included in a capsule in accordance with the present invention. Since each scanning device is relatively small, it can be configured in a spaced array, for example, a wide field of view that encompasses the entire 360 degree field of view of the inner surface of the lumen. Alternatively, as shown in FIG. 19, a single scanning device can be used in capsule 650 to image the four sides of lumen 672 (after the two sides shown and after the pyramid mirror and its Neither can be seen in this figure, including the opposite side). The capsule 650 is connected to a tether 652 that extends outside the lumen 672. A movable optical fiber 654 within the capsule emits light that is directed through the lens 656 toward the pyramidal mirror 658. Adjacent mirror surfaces of pyramid mirror 658 reflect light from lens 656 in four different directions through lenses 660a and 660b (the other two lenses are not shown). Light reflected from the inner surface of lumen 672 is detected by annular detectors 670a and 670b (the other two annular detectors are not shown). If the extent of image overlap provided on the four sides of the capsule 650 is incomplete, the user can rotate the tether 652 as indicated by arrow 674 which causes the capsule 650 to rotate To change the direction in which surface scanning occurs, additional images are generated and optionally joined together to form a full stereoscopic field of view of the inner surface of the lumen.

Combined Tether / Capsule Position Sensor To increase the accuracy and accuracy of measuring the relative position of the tether / capsule, two optical or magnetic sensors can be used simultaneously to read the label on the tether. Interpolation between the optical or magnetic scaling provided by the sign is also used. The spacing between these two or more sensors can be precisely determined and one sensor can be used to measure one step while the other sensor can measure one-half step. FIG. 21 illustrates an exemplary embodiment of a dual color coding pattern 800 with dual sensors. In order to detect red analog or digital mark 818 on tether 820, red laser 802 generates red wavelength light that is directed somewhere in free space, ie, as shown in the present exemplary embodiment, It is directed towards the lens 806 through the fiber 822 and collects red light on the double color coded pattern 818. Red light reflected from the red portion of the dual color coding pattern passes through lens 808 and is transmitted to either free space or red wavelength photodetector 804 through optical fiber 824 as shown. Similarly, on the opposite side of the tether 820, a green laser generates light having a green wavelength that is transmitted through free space or optical fiber 826 towards the lens 814 and onto the double color coded pattern 818. Collect the light. Green light reflected from the dual color coding pattern passes through lens 816 and transmits the green light to free wavelength or optical fiber 828 as shown to green wavelength photodetector 812. Appropriate red and green bandpass filters (not shown) are suitably included in the red and green light detectors, respectively, to limit the wavelength of light reaching the photodetector photodiode. The red and green photodetectors each generate position signals that are processed to effectively double the resolution, which allows the relative position of the tether 820 and the capsule to which it is coupled to be within the SFE master. Determined by the processor. Desirably, the relative position of the capsule in a body cavity such as the esophagus is determined with a resolution of at least 1.0 mm. Instead of red and green light encoding and detection, other combinations of colored light can be used. For example, a red light source, an infrared light source, and a photodetector can be used because the wavelength of red light and infrared light is a maximum sensitivity wavelength band (700 that can be used as a two-wavelength photodetector). This is because it is within ~ 900 nm.

  As another option, the actual high resolution scale can be printed during the optical contrast notation on the tether, and the non-contact sensor enables high spatial resolution “reading” of the SFE in-core processor scale. A characteristic reader can be included. In addition, the physician can read the scale on the tether directly visually while using the tether to position the capsule in the body cavity.

  22A and 22B illustrate details of the tether 830 and include a carrier structure 832 around a central region 838 in which optical fibers, electrical wires, lumens, etc. are disposed. On the outer surface of the carrier structure 832 is a data layer 834 (ie, a tape or mark carrying analog or digital position information is applied). Finally, a protective coating that is biocompatible and prevents the data layer from being cut or damaged covers the data layer. The protective coating can include a transparent polymer or other suitable transparent biocompatible material.

  For use in screening for BE in the esophagus, physicians generally want to first use the capsule scanning function to image the area directly above and near the gastroesophageal junction where the esophagus connects to the stomach. The average distance from the patient's mouth down the esophagus to the position of the capsule suitable for scanning to generate an image of this region is about 39 cm. To facilitate the initial position of the capsule, as shown in FIG. 23, the tether 652 can be provided with a visual indication, such as a red mark 840, about 39 cm above the capsule 650. That is, when the doctor observes that the red mark is placed around the patient's lip, in the average patient, the capsule 650 has been taken down the esophagus to a point just above the gastroesophageal junction. Becomes clear. The doctor can confirm this position of the capsule by viewing an image of the area near the capsule at that point. The position of the capsule can be adjusted slightly, and if necessary, additional separate colored visible marks 842 and 844 are provided on either side of the red mark 840 to prevent the physician from going out of the way of fine tuning. To assist. Of course, the position signal generated by monitoring the data provided on the tether with a non-contact position sensor can also be used to make fine adjustments. Once the initial position relative to the gastroesophageal junction is determined, the position can be used as a reference position for the relative position determined from position data on the tether.

  24-26 illustrate three different exemplary embodiments, which are slightly different 3 for delivering a fluid pulse (generally an air pulse) to a location near the distal end of the tether or capsule. Explains one method. Using fluid pulses such as air to assist in moving the capsule more easily in the esophagus (or other body cavity) and especially when moving the capsule through the LES between the esophagus and stomach can do. In order to facilitate the free movement of the capsule through the esophagus and through the LES, an air pulse is delivered down the lumen in the tether 850 via a tube 856 from a pneumatic source (and a valve supplying the air pulse). Is done. The lumen passes through the capsule and opens into the body cavity at an orifice 854 formed in the capsule 858 housing. This bolus or air pulse is thus selectively delivered into the esophagus (or other body cavity) at a point near the capsule, dilating the esophageal wall and spontaneously opening the upper LES.

  Another exemplary embodiment for delivering an air pulse as shown in FIG. 25 includes a shoulder wheel tube that is mounted along the outer surface of the tether 860 and is located near the distal end of the tether. Due to the positioning port 864, the air pulse is released into the esophagus near the capsule 866. Both the exemplary embodiments shown in FIGS. 24 and 25 provide directed air pulses that can be used to force non-axisymmetric effects and their reaction to air pressure. The resulting capsule movement and tissue reaction can be controlled to manipulate and position the capsule relative to the lumen wall. In contrast, FIG. 26 illustrates an exemplary embodiment in which the tether 870 is used as a guide wire for a larger tube 872 and applies axisymmetric pressure from a fluid pulse. A tube 872 is disposed at its proximal end and is disposed at its distal end with an annular opening 876 for receiving a pressurized air pulse from a pneumatic source and a valve (both not shown). Air pulse with other annular openings 874 near the distal end of the capsule and near the capsule 866, so that the air pulse is spontaneously outside the inner wall of the esophagus or other body cavity where the capsule is placed Cause expansion to. Other techniques for supplying air pulses or other types of fluids can also be used for this purpose.

  While the concepts disclosed herein have been described in connection with preferred embodiments for implementing them and variations thereof, those skilled in the art will recognize that many other variations thereon are within the scope of the following claims. It will be understood that this is possible within. Therefore, the scope of these concepts is not limited in any way by the above description, and is completely determined by referring to the claims below.

Claims (1)

A method for monitoring the relative position of a scanning capsule within a body cavity, wherein the scanning capsule extends outside the body cavity and is generated within the scanning capsule that is convenient for generating an image of the interior surface of the body cavity. In a method coupled to a tether carrying a scanning signal,
(A) providing sign data encoded along an axial length of at least a portion of the tether, wherein the encoded sign data is along the axial length of the tether; Providing either an analog data indication of the position or a digital data indication; and
(B) automatically sensing the encoded tag data using a sensor responsive to the encoded tag data without requiring physical contact with the tether; Generating a position signal indicative of a position, ie, an arrangement of the scanning capsule within the body cavity.

Images