CH707046A2

CH707046A2 - Pressure measuring device for measuring blood pressure of e.g. vein, has pressure sensor that is arranged for measuring the pressure in the liquid in container of ultrasonic measuring unit

Info

Publication number: CH707046A2
Application number: CH01725/12A
Authority: CH
Inventors: Ulrich Baumann
Original assignee: Veinpress Gmbh
Priority date: 2012-09-24
Filing date: 2012-09-24
Publication date: 2014-03-31
Also published as: CH707046B1

Abstract

The pressure measuring device (300) has an ultrasonic measuring unit (350) comprising a container (330) which is filled with an ultrasound transparent measurement liquid. The container of ultrasonic measuring unit is configured such that ultrasound measurement signal is passed through first and second ultrasound transparent windows and fabric. A pressure sensor (325) is arranged for measuring the pressure in the liquid in container. Independent claims are included for the following: (1) pressure measurement system; and (2) method for blood pressure measurement of vein or organ.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a pressure measuring device according to the preamble of claim 1, as well as a system for the pressure measurement of veins or organs according to claim 7 and a method for pressure measurement according to claim Of a living being, whereby at the same time the tissue is observed by means of ultrasound and its reflection on tissue evaluating processes.

[0002] In general, ultrasound examinations are known with the aid of commercially available ultrasonic measuring units, in particular transducers and imaging methods from the medical examination day. Ultrasound is radiated into the tissue, reflected there, and the transit time differences are processed by image-forming methods into an image of the interior of the tissue to be examined. The use of a pressure on the transducer for the characterization of pressure-induced tissue and vessel changes is well established. In particular, this is used in venous compression for thrombosediagnostics. However, in the case of these examination procedures, the pressure exerted depends on the operator's experience and varies from examiner to examiner. In the context of the representation of vessel structures and body fluids moving therein, in particular Doppler methods are used to determine the flow velocity, which necessitate additional equipment for commercial ultrasound equipment. From the prior art it is known from US Pat. No. 6,086,533 A to provide an ultrasonic measuring head with a container in the form of a bubble filled with an ultrasonic permeable liquid in order to be able to measure the pressure applied by the ultrasonic measuring head to a tissue. For this purpose, pressure is exerted on the preceding bubble by means of the ultrasonic measuring head, which pressure exerts this pressure on the underlying tissue. Thus, the force which an operator exerts on a tissue surface lying underneath can be determined. Furthermore, the speed of the body fluid flowing in the vessel is measured by means of a Doppler method. Subsequently, the fluid pressure in the vessel can be determined from the force applied externally and by means of the flow velocity. However, practical tests with such arrangements have shown that the spatial resolution of the ultrasonic measuring heads customary in medicine is regularly severely impaired or rendered unusable by the introduction of such a pressure measuring device. This document also teaches that the pressure in the bubble can be regulated by means of a pressure regulator (23; in FIG. 2). Accordingly, the pressure applied by the contact surface of the bubble,

[0003] Furthermore, a pressure measuring device for ultrasonic measuring devices is known from the publication EP 1415 596 A1. The pressure measuring device described there, from which the article of application originates, essentially consists of a rigid container, for example in the form of a flat hollow cylinder. A rigid membrane, which is used for coupling to the ultrasonic measuring head, is let in on a flat side. On the opposing flat side, a flexible support membrane is provided, which seals the chamber formed by the housing. The interior of the pressure measuring device is filled with an ultrasound-permeable liquid as completely as possible and without bubbles. As can be seen from FIG. 2 of EP 1415 596 A1, an attachment piece is located on the housing, Via which this can be connected with a liquid reservoir. A line is shown in FIG. 1, with which the pressure present in the pressure measuring capsule can be determined by means of an external apparatus.

SUMMARY OF THE INVENTION The object of the present invention is thus to provide a pressure measuring device and a system as well as a method for the pressure measurement of veins and organs which are less susceptible to faults and easier to operate than previous solutions.

The object is achieved for a pressure measuring device according to the features of patent claim 1 and for a system for venous pressure measurement according to the features of claim 7, while patent claim 8 provides a solution for a method for venous / organd pressure measurement.

[0006] Advantageous further developments are set forth in the figures and in the patent claims dependent on the aforementioned claims.

According to the invention, a pressure sensor for measuring the pressure in the liquid is provided in a further development of the pressure measuring device, and the container encloses a closed measuring liquid volume.

[0008] In this way, it is advantageously avoided that the position of a measuring apparatus influences the pressure in the container (pressure measuring capsule), as is the case in the art, according to the principle of communicating tubes. In a particularly advantageous manner, therefore, calibration steps (zeroing) which are preceding the measuring operation can be dispensed with in this context.

[0009] The pressure sensor is advantageously arranged in the housing and is particularly advantageously integrated directly in the housing. In this way, the pressure measuring device is easily transportable and can be operated by a person by himself.

[0010] In a further development of the pressure measuring device according to the invention, output measurement values of the pressure sensor can be transmitted particularly advantageously via connecting cable or radio. As a result, the pressure measuring device according to the invention can be used more flexibly, or a downstream evaluation device can be designed less complex, since preprocessing of the signals can already take place in the region of the sensor.

[0011] In a particularly advantageous manner, a further processing unit for processing the values determined by the pressure sensor is provided in a further development of the pressure measuring device. In this way, more complex measured values, in particular measuring series, can be brought into context and systematic measurement errors can be eliminated.

[0012] The further processing unit is advantageously arranged in the housing and is particularly advantageously integrated directly in the housing. In this way, the pressure measuring device is easily transportable and can be operated by a person by himself.

[0013] In a particularly advantageous manner, a display unit is provided in a further development of the pressure measuring device according to the invention in order to display the determined or further processed measured values in a clear manner. By means of this display unit, it is also advantageously possible to display the actual ultrasound images and more advantageously also data of the image evaluation (eg quality data, status data, statistical data, alarm values, etc.).

[0014] Particularly advantageously, in particular, if the further processing device is provided in the region of the sensor and is capable of handling complex processing tasks, the further processing unit essentially consists only of the display unit.

[0015] Advantageously, depending on the embodiment, the display unit can be arranged on the pressure measuring device or in a separate housing unit. This allows the greatest possible flexibility in the design of the pressure measuring device according to the invention and an exact adaptation to the particular application.

In a further development of the pressure measuring device according to the invention, the measurement can be initiated remotely controlled by means of radio buttons, or special evaluation algorithms or display modes can be set on the display unit by means of function buttons. In particular, an automatic measuring operation can be initiated, for example by means of the function keys, or a manual pressure measurement can be carried out with the aid of the display.

[0017] In a further development of the pressure measuring device according to the invention, it is particularly advantageous to provide a flange for the ultrasonic measuring unit or at least for an ultrasonic measuring head. In this way, a measuring unit consisting of an ultrasonic measuring head and a pressure measuring device can be formed quickly and reliably.

In an alternative embodiment of the invention, the ultrasonic measuring unit, or at least the ultrasonic measuring head integrated component of the pressure measuring device, with which the pressure measuring device is easily transportable and compact in design.

In a particularly advantageous manner, in a further development of the pressure measuring device, a pressure generating device is provided for pressurizing at least the ultrasonic transmittance measurement liquid in the container so that a corresponding pressure can be generated in the container so that the at least one flexible window adjoins the surface of the fabric Thus enabling a reliable measurement. Advantageously, a specific reference pressure is generated in the container with the printer-producing device, which serves as the initial value for the subsequent measurements or evaluations.

[0020] The printer generating device is advantageously arranged in the housing and is particularly advantageously directly integrated in the housing. In this way, the pressure measuring device is easily transportable and can be operated by a person by himself.

[0021] In a particularly advantageous manner, in a pressure measuring system for the pressure measurement of a vein or an organ, a pressure measuring device can be combined with a measuring unit combined with an ultrasonic measuring unit or connected to it. The appropriate time for the pressure measurement can be determined by pressure exertion of the combined device on an underlying tissue with simultaneous measurement and ultrasound imaging by promptly observing the change in the tissue.

In a further development of the system according to the invention, the pressure of the collapsing vein or the degree of deformation of the organ can be determined in a particularly advantageous manner. An organ does not have to be completely imaged in the ultrasound for the pressure measurement, since the pressure measurement can be carried out on only one part of the body with the aid of repeatable and reliable measurement results. As a result, large organs such as a liver, for example, can also be measured.

[0023] In a further development of the system according to the invention, the time of the colocalization of the vein can be determined particularly advantageously, for example, by computer evaluation of the ultrasonic measurement values, in conjunction with the pressure measurement values.

[0024] In a further development of the system according to the invention, the timing of the convoluting can be determined particularly advantageously by image-processing and / or image-evaluating methods which analyze ultrasound images.

In a method for the pressure measurement of a vein or an organ according to the invention, a venous pressure can be determined by a pressure measuring device according to one of claims 1 to 6, in that the combined ultrasonic measuring unit and pressure measuring device is pressed onto a tissue in a partially automated manner A signal evaluation is detected that a vein is collapsed or a certain degree of deformation of an organ is reached and the corresponding pressure in the pressure measuring capsule is measured.

Advantageously, depending on the complexity of the pressure measuring device, already preprocessed signals can be forwarded to a display and / or evaluation unit by radio or connecting cable in the aforementioned method variable. In this way, the method for the pressure measurement can be formed optimally, depending on the application of existing infrastructure.

[0027] A software for carrying out the image-processing method is preferably provided. Such a software is itself a self-contained invention. The collapsed state of a vein is thereby recognized by the conversion of raw data (pixels) into a cross-sectional area of the vein. A cross-section of the unstressed vein can be used to define any cross-sectional reduction as a criterion for the Kol-labieren. In the case of organs, the degree of deformation of the organ or of the organ part is accordingly determined by the displacement of tissue-induced pixel abnormalities (eg blood vessels, density differences, etc.). As already stated, for a pressure measurement with the pressure measuring device of an organ according to the invention, this must not be completely imaged in the ultrasound.

In an advantageous further development of the software, the automatic recognition of the beginning of the measuring cycle is defined by the beginning of the deformation of the vein or by the beginning of the reduction of the through-flow cross section area. In the case of organs or organ parts, the time at which pixel abnormality starts to shift is advantageously selected.

In a further advantageous further development of the software, the automatic recognition of the measurement quality is defined by determining the position of the observed vein or the organ or the organ part opposite the measuring axis of the ultrasonic transducer or ultrasonic transducer and / or the container of the pressure measuring device. Advantageously, the position of the vein or the organ is also taken into account in the case of adjacent and in particular underlying structures such as bones or the like.

[0030] In an advantageous further development of the software, an automatic decision is made about acceptable or unacceptable measurement by taking into account and analyzing all the aforementioned data.

Further advantages, features and details of the invention will become apparent from the following description, in which embodiments of the invention are described with reference to the drawings. The features mentioned in the claims and in the description can be individually relevant to the invention individually or in any desired combination.

[0032] The reference list and the claims are part of the disclosure. The figures are described in a coherent and comprehensive manner. Identical reference symbols mean identical components, reference symbols with different indices indicate functionally identical or similar components.

[0033] In this connection,

1 shows schematically an ultrasound measuring head with a pressure measuring device in side view according to the prior art; FIG.

FIG. 2 shows an embodiment of a device according to the invention, which is coupled via a connecting cable to a separate housing unit; and

FIG. 3 shows an example of a device according to the invention, which is coupled by radio to a separate housing unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As is shown in detail in FIG. 1, which is an example from the prior art, which forms the basis of the present invention, an ultrasonic measuring head 2 (or ultrasonic measuring unit) with a pressure measuring device is shown in a side view. The following explanations relate, on the one hand, to the embodiment known from the prior art and also to the corresponding elements of the embodiments according to the invention.

The embodiment shown here is distinguished by the fact that the contact pressure is exerted by a force 1 on the ultrasonic measuring head 2 on the ultrasonic measuring unit 7 on the tissue 4, such as, for example, the flare of a person, for example on an arm. The resulting pressure can be measured and displayed quantitatively during the examination. For this purpose, an embodiment of a pressure measuring device is designed as a container 5 in the form of a pressure measuring capsule on which a commercially available ultrasonic measuring unit 7 can be coupled for ultrasonic measurements. It is conceivable for a person skilled in the art that an overall integrated pressure measuring device can also be designed as a unit with an ultrasonic measuring unit.

[0036] The size and shape of the container 5 can be varied according to the application and task. In addition to the fixed coupling or constructive integration on or in the transducer, various connections to known sound heads are conceivable. A gel 8 is preferably used between the pressure measuring device and the ultrasonic measuring unit. A pressure measurement can be carried out by means of commercially available pressure transducers by measuring the pressure in the liquid located between the ultrasonic measuring unit and the supporting membrane. For this purpose, the liquid volume can be connected via a hose to a commercially available pressure measuring device (not shown).

In this embodiment, the liquid 11 in the interior of the container 5 for pressure measurement is connected to a line 12 with a pressure measuring device (not shown). It is particularly important that the liquid does not obstruct the ultrasound passage and is, as a rule, completely transparent to ultrasound. In this connection, glycerin-water mixtures or a similar liquid have proven particularly suitable. The illustrated container 5 is closed by a flexible ultrasound-permeable support membrane 13, which can also be designed as a compliant window, on the side which serves to rest on the tissue 4. In practical tests, it has been shown that the material and the design of this support membrane 13 have a great influence on the quality of the ultrasound measurement. In numerous tests, silicone elastomer was determined as suitable. The type MVQ (international short), which is characterized by the following data: Hardness 50 ° Shore A; Density 1.15 g / cm3; Appearance milky transparent. The thickness of the supporting membrane should be as small as possible, for example 0.4-0.5 mm. The material MVQ could easily be used with a thickness of 1 mm. Smaller thicknesses are advantageous, but have the disadvantage that they are easier to damage and wear more quickly. Thicker membranes on the order of 3 mm and more, on the other hand, considerably affect the ultrasonic measurement result. A gel 17 is preferably introduced between the support membrane / the compliant window 13 and the tissue surface 15 in order to improve the coupling of the ultrasound into the tissue 4. A window 20 is let into the rear side 19 of the container 5. The window 20, like the support membrane / compliant window 13, also consists of an ultrasonically permeable material, which preferably has a low flexibility.

When the ultrasonic measuring unit 7 is placed on the rear side 19, the window 20 can adapt itself to the shape of the forehead 22 of the ultrasonic measuring unit, which is often slightly curved. As a material for the window Teflon® (polyfluoroethylene, Dupont) has proved to be suitable in a thickness of approx. 0.05-0.7 mm. Thicknesses of the order of 1 mm or more lead to a marked deterioration in the quality of the ultrasonic measurement. From a thickness of 3 mm of this curved window the measurements were virtually useless. Preferably, the curved window 20 and the flexible window or support membrane 13 are held in a metal frame 24.

In the following description as well as in the patent claims of this invention, the curved window window 20 is also referred to as a first window and the flexible window / support membrane 13 also as a second window. In this context, it is particularly advantageous in such an embodiment that, for example, all the housing components of the container 5, in addition to the windows 13 and 20, are designed to be as hard as possible in order to be pressurized, so that the entire force 1 is pressurized The tissue surface which is measured and the measured pressure is not falsified by compliant housing components. With regard to the frame 24, which does not need to have any special properties with respect to ultrasound,

[0040] For example, the frame holder 26 is fastened on the rear side of the container 5, between which the ultrasonic measuring unit 7 can be inserted. The holders 26 can, for example, be equipped with spring elements in order to hold the measuring head 7. A variant with hook-and-loop fasteners 28 is shown, which allows stable, pressure-free fixing of the ultrasonic measuring unit 7 on the container 5. For example, pivoted blades 30 are provided on the holder 26, which can be pivoted about rods 32 and are provided with a Velcro strip for fixing the ultrasonic measuring unit 7. For the embodiment of the connection between the receptacle 5 and the ultrasonic measuring unit 7, any technical variants are conceivable. In the most extreme case, an inseparable connection is provided between the ultrasonic measuring unit and the pressure measuring device.

In embodiments of the invention, the first window 20 as well as the second window / support membrane 13 can be made of polytetrafluoroethylene, abbreviated PFTE and registered as the brand name with the designation Teflon of Dupont. It does not matter whether only the first window 20, the second window 13 or both windows are made of this material. The advantage of this material, when used in embodiments of the invention, is that fewer losses occur, no preloading occurs, and thus a more accurate pressure measurement is possible. The support membrane 13 can, for example, be made of a shrinking flock. If the first window 20 or the curved disc has a low elasticity, this has the advantage that less losses occur and the measurement thereby becomes more accurate.

FIG. 2 shows an exemplary embodiment of a pressure measuring device according to the invention. A human forearm 110 serving as a tissue 4 is shown as well as a pressure measuring device 300 which consists of an ultrasonic measuring unit 350 with a supply and control supply line 340 as well as a container 330 (pressure measuring capsule) with an annular 331. The receptacle 330 is coupled to a pressure sensor 325. In addition to a circular ring-shaped design, as shown in the present exemplary embodiment, this housing section 331 could also have a polygonal annular design. Furthermore, it is conceivable that the annular housing section 331 has a polygonal outward contour and a circular internal contour or a circular outward contour and a polygonal inside contour.

[0043] Further, an operation button 335 is attached to the pressure measuring device 300 for starting the measurement. In this exemplary embodiment, a pressure evaluation electronics 345 is also provided in the form of a processing unit in a housing 305. This is implemented, for example, as a processor in the form of a microprocessor or microcontroller. In this embodiment, the pressure evaluation electronics 345 is connected to a display unit 130 with a keyboard 310 by means of a data cable 420. The display unit 130 with the keyboard 310 forms a separate housing unit 400.

The receptacle 330 for the ultrasound-transparent measurement liquid is particularly advantageously embodied and the pressure sensor 325 is coupled directly to the closed volume. In cases where a filling plug is found to be necessary on the receptacle 330 with the annular housing section 331, this is tightly closed during the pressure measuring operation. The nature and quantity of the data which is passed on to the display unit 130 is derived from the complexity of the measurement data processing carried out in the pressure evaluation electronics 345. In the extreme case, only graphical data can be made available via the data line 420. However, there is also the possibility that the pressure evaluation electronics 345 converts measurement signals from the pressure sensor 325 and determines pressure values therefrom, Which are then made available to the display unit 130. It is furthermore conceivable for data to be stored and further processed in the display unit 130 so that, for example, an average value formation of different measurements can be carried out or measurement series or series can be compared by different operators. Furthermore, it is possible to determine and compensate for systematic errors in the measurement. Compensation can either be carried out within the scope of a display preparation or directly taken into account during the measuring process by setting modified measuring parameters in the pressure evaluation electronics. So that, for example, an average value formation of different measurements can be carried out or measurement series or series can be compared by different operators. Furthermore, it is possible to determine and compensate for systematic errors in the measurement. Compensation can either be carried out within the scope of a display preparation or directly taken into account during the measuring process by setting modified measuring parameters in the pressure evaluation electronics. So that, for example, an average value formation of different measurements can be carried out or measurement series or series can be compared by different operators. Furthermore, it is possible to determine and compensate for systematic errors in the measurement. Compensation can either be carried out within the scope of a display preparation or directly taken into account during the measuring process by setting modified measuring parameters in the pressure evaluation electronics.

Pressure measurement values can be displayed on the display unit 130, for example. It is also possible, in parallel, to display an image of the vein 6 and to compare the actual values measured in the tissue 4 with this image.

Furthermore, a printer generating device 370 is provided in the housing 305, by means of which the pressure of the measuring liquid 11 in the container 330 can be increased. For example, the pressure is increased by a mechanical piston of the printer generating means 370, which compresses the closed volume. The pressure generating device 370 is, for example, electrically, pneumatically and / or hydraulically operated and is designed in accordance with the medium used. The pressure sensor 325, provided in the housing 305, measures the pressure in the measuring liquid 11 periodically or continuously during the pressurization by the printer generating device 370.

In this context, it is important to understand that, in the prior art, the pressure measurement does not take place in a closed housing. As a result, the position of a pressure measuring device or of a pressure regulating device, as described in US Pat. No. 6,086,533 A, can lead to falsifications of the measuring result in the case of an insufficient prior nulling, according to the principle of the communicating tubes. Furthermore, it is to be noted that the coupled liquid-carrying components, such as, for example, the line 12 to the pressure measuring device and other liquid-conducting components located there, have a considerable effect on the result of the measurement due to their elastic properties and the fact that the liquid has a larger surface area can. In particular, it is important in this connection to take into account that the volume of liquid in the container is relatively small for an improved ultrasound passage, and a correspondingly larger liquid volume, which is added by the line to the pressure measuring device and the liquid-carrying components in the pressure measuring device, cause a certain measuring inertia Can falsify the measurement. In particular, in such a device according to the invention, a calibration operation (zeroing) is omitted in order to compensate for the influence of different liquid levels between the pressure measuring capsule and the pressure measuring device. Which pass through the line to the pressure measuring device and the liquid-carrying components in the pressure measuring device, can cause a certain measuring inertia and therefore can falsify the measurement. In particular, in such a device according to the invention, a calibration operation (zeroing) is omitted in order to compensate for the influence of different liquid levels between the pressure measuring capsule and the pressure measuring device. Which pass through the line to the pressure measuring device and the liquid-carrying components in the pressure measuring device, can cause a certain measuring inertia and therefore can falsify the measurement. In particular, in such a device according to the invention, a calibration operation (zeroing) is omitted in order to compensate for the influence of different liquid levels between the pressure measuring capsule and the pressure measuring device.

FIG. 3 shows a further exemplary embodiment of a pressure measuring device according to the invention. 2, FIG. 3 shows the difference that the data line 420 is replaced by a radio link, which consists of a transmitter 315 and a receiver 320. The design of the spark gap can be carried out in a manner known from the prior art. It can be unidirectional or bidirectional. If necessary, the Bluetooth® or Zigbee® standard is the basis for the radio connection. 2, the embodiment in FIG. 3 also has the advantage that only one connecting cable 340 is needed to supply the ultrasonic measuring unit 350 and thus a simpler flammability of the pressure measuring device 360 in the pressure measuring process is provided.

Furthermore, it is possible to receive the data emitted by the transmitter 315 several times by means of a plurality of receiving devices and to appropriately further process them. For example, pressure measurement series can be stored in order to determine systematic measurement errors. In addition, different measurement data sets can be compared with one another for training purposes.

2 and 3, the ultrasonic measuring unit 350 each form a pressure measuring system with the pressure measuring device 300 or 360. In the embodiment according to FIGS. The ultrasonic measuring unit 350 is advantageously mechanically coupled to the pressure measuring device 300 or 360 and particularly advantageously with this. To this end, the means which have been described for the coupling according to the embodiment shown in FIG. 1 are used, for example.

[0051] Components of the housing sections of the container and, in particular, its annular housing section 331 of the plastic PEEK (polyetherether ketone) can preferably be designed. This material has the advantage that it has a high hardness (ISO 668, ISO 2039-2) of M99 and thus is particularly suitable for application in pressure measuring devices. Furthermore, this material can be easily injection-molded and thus is the basis for a cost-effective production of the pressure measuring device according to the invention.

In particular, pressure gauges and organdrums can be determined with the pressure measuring devices 300 and 360 according to the invention. This allows, for example, a fast and cost-effective measurement of the peripheral and central pressure (ZVD). The previous conventional measurement is made invasively by inserting a catheter into the heart. Such a measurement has a complication rate of about 20% and is associated with a partial serious risk to patients. In addition, the insert of the catheter takes about 23 minutes and must be performed by two persons, of which a doctor must necessarily. The procedure is relatively expensive. On the other hand, the pressure measuring system 100, 300, 360 and 500 according to the invention provides a non-invasive, faster, simpler, more cost-effective and non-invasive measuring method for pressure measurement.

The use of the pressure measuring system according to the invention leads to faster operating sequences and allows a largely automated measurement of the central venous pressure, similar to that of commercially available blood pressure measuring devices for arterial blood pressure. For this purpose, a combination of an ultrasonic measuring head 350 and a pressure measuring device 300 according to the invention is placed on a patient tissue to be examined, for example, on the arm 110 of a patient, and the pressure resulting from the contact force is measured in the tissue 4 via a pressure measuring device. At the same time, it is observed by ultrasound how a vein 6 located in tissue 4 behaves. As soon as, for example, the vein 6 collapses, the associated pressure in the tissue 4 can be determined,

The measuring method is, of course, not restricted to veins, but can also be used in other tissue structures, in particular in organs or organ parts (eg the liver or the spleen) and other body fluids.

[0055] Advantageously, the measuring operation can be started automatically. As soon as a pressure pulse from the pressure sensor 325 is measured, for example, the display device 130 can be switched on, and the ultrasonic measuring unit 350 can also be started via a suitable signal. An automatic starting procedure has the advantage that the pressure measuring system 300 or 360 according to the invention can be used energy-efficient. It is also conceivable that the time at which a vein 6 or another body fluid vessel collapses can be determined automatically by suitable analytical methods. For example, it is conceivable that the change in the flow noise as an indicator for the collapse of a vein 6 is used by means of a structure-borne sound microphone, the change in a blood-flow sound. It is also conceivable, (Eg, arm 110) to image the location of a vein 6 and to determine the geometry change thereof by image processing methods generated by image processing techniques from the interior of the tissue 4 in an extremity. In this way, a detection of the collapse of the vein 6 can also take place, in order to determine the time of the correct measurement of the venous pressure. This point in time is then determined as the time at which the central venous pressure was determined in the course of the pressure measurement. To determine the time of the correct measurement of the pressure. This point in time is then determined as the time at which the central venous pressure was determined in the course of the pressure measurement. To determine the time of the correct measurement of the pressure. This point in time is then determined as the time at which the central venous pressure was determined in the course of the pressure measurement.

[0056] Furthermore, an image of the vein 6, which is observed by means of ultrasound, can be displayed side by side or one above the other on a display unit 130 at the same time as the printing process. Such an embodiment offers the advantage of a compact representation and allows only one display device 130 to be provided for several display functions.

In further embodiments, it is, for example, conceivable to collect the measured values measured by the pressure measuring device according to the invention and to use them for quality control in order, in particular, to understand the correct position of the pressure detection, ie the correct position over a vein 6 And to be able to ascertain whether the correct and sufficient force for the pressure measurement has been exerted on the tissue 4.

In general, automated methods in embodiments of the pressure measuring device 300 or 360 according to the invention and of the pressure measuring system according to the invention have the advantage that fewer errors occur. Furthermore, it is also conceivable to use the method for measuring the stiffness of the sley. For this purpose, the liver is deformed to a certain degree of deformation by means of the increasing pressure in the measuring fluid, the ratio of the degree of deformation to the pressure being the measure for the resistance to leaching. Alternatively, the liver stiffness can also be measured by determining the pressure of a liver vein and, conversely, the higher the pressure in the hepatic vein, the stiffer the liver tissue is.

[0059] Possible user errors during the pressure measurement and measures are described below. - The arrangement of the pressure measuring device is too far from the axis with respect to the target vein and therefore no peak pressure is exerted on the vein. Therefore, the method of venous pressure measurement according to the invention should preferably perform a detection of the central axis of the pressure measuring system and a comparison thereof with the target vein. Preferably, the target vein is marked in color on the display unit. If the pressure measuring device is not in an ideal position for an accurate pressure measurement, preferably a warning is issued by the inspector with a request to correct the position of the pressure measuring device and the pressure measurement is not released. - The pressure exerted by the pressure measuring device on the vein is uneven and leads to asymmetric tissue displacement between the pressure measuring device, which touches the tissue 4 and the vein 6. Therefore, according to the invention, surface displacement and elastographic methods are preferably employed to detect such cases. Preferably, in such a case, a warning of the inspector is issued with a request for correction with a request for a uniform pressure application, and there is no release of the pressure measurement. - An arrangement of the pressure measuring device is placed in an unsuitable place. According to the invention, an evaluation of the contact area for the pressure measuring device is provided as a remedy. For example, a suitable location for venous pressure measurement is found by searching for internal bone 8 below the target vein 6. Preferably, a warning is issued by the examiner with a request to correct the placement of the pressure measuring device and the pressure measurement is not released. In the case of the embodiments described in FIGS. 2 and 3, the system pressure in the measuring liquid 11 should preferably be set to zero before the measurement (zeroing). A preferably provided automatic calibration function allows the pressure measuring system to calibrate itself before measurement. This should preferably be done according to the invention by the detection of the current pressure together with the illustrated ultrasound image. For this purpose, for example, a specific pressure increase rate, for example With respect to a reference pressure defined by the examining or the pressure measuring system, in conjunction with an ultrasound image, by means of which the tissue displacement is detected, for example, by the use of elastographic methods. There is therefore no need for a calibration of the pressure measuring system for the pressure measurement by the examiner before the start of the measurement and a corresponding calibration error is advantageously avoided. A visible representation of the measuring cycle is also advantageously provided. An automatic detection of the point in time at which the measurement was started can be performed by evaluating the venous geometry and its deformation (for example, the start of the measurement at 5% of the geometry change from venous height to venous width).

Furthermore, it is preferably possible for the investigator to be informed about the fact that the measurement has begun. For example, this can be done by changing the colors of certain areas of the screen or the display unit. Advantageously, this ensures that the examiner knows that a measurement cycle has been started, and furthermore, a further date for evaluation is provided to the examiner in the form of the initial pressure during the first movement of the vein geometry. - A visual representation of the end of the measuring cycle is also provided. This allows an automatic detection of the time at which the vein 6 is collapsed and the measurement has been completed by evaluating the vein geometry and its deformation. For example, "termination" may be preferably defined,

Preferably, the investigator is notified of the fact that the measurement has been completed. This is done, for example, by changing the colors of certain areas on the screen and by displaying the result of the measurement in, advantageously large, digits on the display unit (screen). It is thus advantageously ensured that the examiner knows that a measuring cycle has been completed. This data can be used and a new measurement can also be started. Preferably, it can be ensured according to the invention that the continuation of the measurement is carried out by means of further data collection at the same position. Therefore, an automatic detection of further measurements is preferably carried out, To carry out a further measurement to the investigator after a poor measurement taking into account the criteria mentioned above. If the measurement cycle is completed, the new measurement is displayed as well. Preferably, an average value with the preceding measurements at the same location is also displayed with the value of the preceding measurement.

Continuous monitoring of the print and the analyzed image advantageously results in an automatic detection of the measuring end. As soon as, for example, the examiner removes the pressure measuring device from the skin of the patient or moves it too far from the starting point of the measurement, the measurement can advantageously be terminated. As a result, a new measuring cycle can advantageously be aborted thereafter as soon as the examiner presses the actuating button on the pressure measuring device or the pressure measuring device comes into contact with the fluff and the pressure rises, whereby tissue 4 can advantageously be detected by an evaluation software. Such an option may, for example, be selected from a personal setting menu within the software. In order not to confuse the examiner and for the sake of a clear presentation, advantageously the measured and evaluated data are displayed in a combined frame together with the ultrasound image delivered by the medical ultrasound device. - In order to provide an investigator with up-to-date information on the quality of the measuring cycle, the detected typologies of skin, surface of the venous pressure device, vein, bone; As indicated above, are displayed on the screen and colored according to their status. For example, topology means green "no problem", red "unacceptable" and orange "critical". Which is delivered by the medical ultrasound device. - In order to provide an investigator with up-to-date information on the quality of the measurement cycle, the detected typologies of skin, surface of the venous pressure device, vein, bone; As indicated above, are displayed on the screen and colored according to their status. For example, topology means green "no problem", red "unacceptable" and orange "critical". Which is delivered by the medical ultrasound device. - In order to provide an investigator with up-to-date information on the quality of the measuring cycle, the detected typologies of skin, surface of the venous pressure device, vein, bone; As indicated above, are displayed on the screen and colored according to their status. For example, topology means green "no problem", red "unacceptable" and orange "critical".

The method according to the invention for the pressure measurement provides a simple procedure whereby a pressure measuring device consisting of a pressure measuring device and an ultrasonic measuring unit can be used for the automated measuring of venous and or organdrian backings.

For the person skilled in the art, modifications in the context of the technical possibilities and the known devices for pressure and ultrasound measurements are conceivable for the person skilled in the art in view of the above description and exemplary embodiments of the pressure measuring device according to the invention for the pressure measurement and the method for pressure measurement.

Reference list 1 Force 2 Measuring head 4 Tissue 5 Container 6 Venee 7 Ultrasonic applicator 8 Bones 11 Measuring liquid 12 Line for pressure measurement 13 Supporting membrane / 2. Window 15 fabric surface 17 gel 20 1. window 24 frame 26 holder 28 hook-and-loop fastener 30 wings 32 rods 100 pressure measuring device 105 housing 110 limb 115 1. housing part 120 2. housing part 125 hinge 130 display unit 135 locking device 140 function buttons 150 function buttons 160 function buttons 170 receptacle 171 1. Window of 170 172 2. Window v.

Claims

claims

1. A pressure-measuring device (300) for combination with an ultrasonic measuring unit (350), comprising: a container (330) filled with an ultrasonic-transparent measuring fluid (11), a first ultrasonic-transmissive window (20) Wherein at least one window is flexible in order to be able to adapt itself to the surface of a tissue, wherein the receptacle is configured such that an ultrasound emitted by the ultrasound measuring unit is transmitted through both of the ultrasound measuring units (11), characterized by a pressure sensor (325) for measuring the pressure in the liquid (11), and by means of a pressure sensor (325)Wherein the container surrounds a sealed measuring-liquid volume.

2. The pressure measuring device as claimed in claim 1, characterized in that a connecting cable (420) is provided for transferring the values determined by the pressure sensor (325), or a transmitter (315) is provided for transferring the values determined by the pressure sensor (325).

3. Pressure measuring device according to claim 1, characterized in that a further processing unit (345), preferably in the housing, is provided for the further processing of ascertained values of the pressure sensor (325).

4. The pressure measuring device as claimed in claim 1, characterized in that a display unit (130) is provided for displaying ascertained values of the pressure sensor (325). The display unit (130) is advantageously arranged in a separate housing unit (210) , The housing unit (210) having at least one evaluation device and / or processing unit and / or function buttons (140, 150, 160, 230, 240) for controlling the device.

5. The pressure measuring device as claimed in claim 1, wherein a flanging device is provided for the ultrasonic measuring unit, or the ultrasonic measuring unit is a component of the pressure measuring device.

6. Pressure measuring device according to claim 1, characterized in that a pressure generating device (370), preferably in the housing (305), is provided for pressurizing at least the ultrasound-transparent measuring liquid (11) in the container (330).

7. The pressure measuring device as claimed in claim 1, wherein the pressure measuring device and the ultrasonic measuring unit are advantageously mechanically combined with one another to form a measuring unit Or are connected to a measuring unit.

8. A method for measuring the pressure of a vein or an organ, in which an ultrasonic measuring unit (350), which is coupled to a pressure measuring device (300) according to one of claims 1 to 6, or in which a printing system according to claim 7 is applied to a tissue (4) (6) or the organ to be measured is placed on the tissue (4), and as long as the pressure on the tissue (4) is increased, until the ultrasound measurement reveals that the vein (6) collapses, (300) is determined as a vented pressure or organs pressure, wherein the evaluation of measurement information preferably takes place at least partially in the region of a pressure sensor (325) and evaluated measurement information is transmitted by radio. (DE) (315,320) or connecting cable (420) to a display unit (130) and / or evaluation unit.

9. Method for the pressure measurement of a vein or an organ according to claim 8, characterized in that the time of the pressure measurement in a processing unit is determined automatically.

10. A method for the pressure measurement of a vein or an organ according to claim 8, characterized in that the time of the collapse of a vein (6) or the attainment of a predetermined degree of deformation of an organ is determined by an image-processing method.