Method and device for automatically determining position of needle tip of biopsy needle

Abstract

The invention relates to a method for the automated determination of the position of the needle tip (N) of a biopsy needle (32), which is arranged in a needle holder (31) and can be moved along the longitudinal axis of a biopsy unit (30) for biopsy by means of the biopsy unit (30) and is guided by means of a needle guide (33), the method comprises the following steps: positioning the biopsy needle (32) in a needle holder (31), ascertaining the position of at least the needle tip (N) of the biopsy needle (32) by means of a sensor (35), and automatically calculating the distance from the needle tip (N) to a reference point. In addition, the invention comprises a device and a mammography system.

Description

TECHNICAL FIELD

[0001] The present application relates to a method and a device for automatically determining the position of a needle tip of a biopsy needle and to a mammography system. BACKGROUND

[0002] During diagnosis, for example in the application of a biopsy in mammography, a puncture needle or a vacuum needle is used, the length of which can be approximately 90 mm to 150 mm. The needle parameters are usually stored in the workstation used and the target position for the electrically moveable biopsy unit is calculated and moved to by means of the needle parameters. For this purpose, the desired biopsy needle is inserted into a needle holder, also called "gun", which can then be moved by means of a usually manually moved slide of the biopsy unit. The biopsy needle is then pushed into the patient by moving the needle holder on the slide. If the tip of the biopsy needle reaches the desired point, a negative pressure is generated therein, so that a tissue sample is sucked into the biopsy needle (or below, also simply referred to as "needle" hereinafter). The determination and calculation of the coordinates of the desired point is typically performed on the basis of a plurality of recordings by means of a "stereoscopic" calculation or reconstruction of a 3D data set.

[0003] After the pre-positioning of the needle holder has been performed, the needle is typically introduced into the examination object in practice, for example by means of a linear feed of the needle holder. Here, the needle is guided by a sterile needle guide.

[0004] The position of the needle in the body is determined by means of repeated X-ray recordings. However, the X-ray recordings each introduce a radiation dose into the tissue, which can be avoided if the position of the needle is known exactly. Furthermore, it must be noted that the entire construction of the biopsy unit does not cast a shadow in the recordings. Therefore, the needle is preferably set at an angle.

[0005] The needle is usually stopped before the desired point, for example the lesion site, in order to be able to check, for example by means of an X-ray recording, whether the needle is positioned correctly. If the needle body is introduced until the end stop, it can be assumed from this that the desired pre-calculated position in the object has been reached (here still before the lesion site). Subsequently, the needle is introduced into the final position for tissue extraction via a spring mechanism, a mechanical drive or by means of a vacuum and extracts the tissue sample.

[0006] Serious problems can arise due to incorrect guidance of the needle or use of the wrong needle type.

[0007] Since the needle manufacturers usually offer a plurality of needle lengths in order to be able to extract tissue samples in different depths of the examination object, there is a risk of missing the intended tissue or of completely penetrating the object when the wrong needle is used, which leads to injuries to the patient and damage to the examination device. If, for example, the wrong needle length is notified to the system, this can lead to (possibly serious) injuries.

[0008] The determination of the needle length is only carried out by manual measurement or by extracting the length from product data or customer documentation. At present, the presence of a biopsy needle is detected via the presence of a needle holder, or for example a flip lever is turned over in order to be able to introduce the needle, wherein the lever is connected with a switch, which prevents the movement of the device and the movement of the needle.

[0009] It can be summarized that the main hazard is the incorrect positioning of the needle tip in the body. The incorrect positioning can occur by incorrectly introducing the needle into the body, or the needle length does not correspond to the information given about the needle length (an incorrect needle is inserted or an incorrect statement is given about the needle length). The incorrect positioning can be identified by means of an X-ray recording. However, this places a burden of the X-ray dose on the body of the patient and must be corrected manually. The incorrect positioning can completely be ignored. SUMMARY

[0010] It is an object of the present application to provide a method and a device for automatically determining the position of the needle tip of a biopsy needle, and a mammography system, with which the above-mentioned disadvantages are avoided.

[0011] The object is achieved by a method for automatically determining the position of the needle tip of a biopsy needle according to the present application, a device for automatically determining the position of the needle tip of a biopsy needle according to the present application and a mammography system according to the present application.

[0012] The method according to the present application serves for automatically determining the position of the needle tip of a biopsy needle, which is arranged in a needle holder and which can be moved on a longitudinal axis of a biopsy unit for carrying out a biopsy by means of a biopsy unit and is guided by means of a needle guide. The method comprises the following steps:

[0013] - positioning the biopsy needle in the needle holder,

[0014] - determining the position of at least the needle tip of the biopsy needle by means of a sensor,

[0015] - automatically calculating the distance from the needle tip to a reference point.

[0016] The information about the distance is then output as information to an operator and / or in the form of a control command. For example, a warning can be output that an incorrect needle has been inserted, or the feed of the needle holder can be prevented.

[0017] For this method, the biopsy needle is positioned in a needle holder. In order to perform a biopsy by means of the biopsy unit, the needle holder can be moved on the longitudinal axis of the biopsy unit, in particular on a slide. The needle is guided during the movement by means of a (sterile) needle guide. Directly after insertion, the needle is typically not yet located in the needle guide. Only when the needle holder has been moved slightly, the needle tip moves through the needle guide and is then guided on its path by the needle guide. All this is clearly known from the prior art.

[0018] With regard to the method steps, the distance determined there can be used not only for determining the needle length but also for determining the needle position. Not only when determining the length of the biopsy needle, but also when determining the position of the biopsy needle, the position of the needle tip and the position of the reference point, for example the needle holder or the needle guide, must be known. It is not necessarily necessary to measure the position of the needle holder, since the position of the needle holder can also be known in advance due to the construction of the biopsy unit in its initial position. The determination of the position of the needle tip of the biopsy needle can completely additionally be monitored by means of X-ray recordings, however this is not necessarily necessary.

[0019] Now, the biopsy needle is first positioned in the needle holder in a known manner.

[0020] Subsequently, the position of at least the needle tip of the biopsy needle is determined by means of a sensor. Preferably, also the position of the needle holder is determined. However, as mentioned, this is not necessarily necessary, since the position, for example in the insertion position, can already be known.

[0021] If the distance of the needle tip to the reference point has been determined, this distance can be used not only for determining the needle length (in the case of a reference point at the needle holder) but also for determining the needle position (in the case of a fixed reference point in space at the needle guide). The distance from the needle tip to the reference point is determined here automatically. The reference point is preferably a point at the needle holder, for example its needle holding point. However, the reference point can also be the needle guide or another point outside the needle holder.

[0022] The calculation of the total needle length is simple by means of the information known in the method. The needle length can be derived from the distance between the needle tip and the needle holder, for example from an image (here, the camera would be the sensor). Although the needle length in the image is not the true needle length, a conversion factor can be determined simply in the case of a predefined recording distance and, if necessary, a plurality of calibration measurements. Thus, essentially only the pixels have to be counted from the needle tip to the needle holder. The actual needle length is then directly derived from the conversion factor.

[0023] With regard to the position of the needle, the distance from the needle tip to a (known) reference point, for example the needle guide or the needle holder, must be calculated. It should be noted here that it is not necessarily necessary to have a certain measuring tip to determine the position of the needle tip of the biopsy needle. It is sufficient to be able to derive the position from the measurement. For this purpose, the position of the needle tip is preferably determined directly at the beginning (when the needle tip is still outside the patient). This can preferably be achieved by determining the position of the needle tip at the needle guide by means of a sensor at the needle guide. The position of the needle holder can then be measured and the current position of the needle tip (given the known needle length) is derived (and thus determined) from it.

[0024] To measure the needle length, it is actually only necessary to carry out these method steps once. In determining the position of the needle tip in the body, the method steps should be carried out several times. It is particularly preferred to determine the needle length before the biopsy needle is introduced, so that it can be checked whether the correct needle has been inserted. The position of the needle tip in the body can then be determined. For this purpose, after the biopsy needle has been positioned in the needle holder, the method steps can be specified as follows:

[0025] a) determining the position of at least the needle tip of the biopsy needle, in particular in the region of the needle guide, by means of a sensor,

[0026] b) automatically calculating the total needle length from the needle tip to the needle holder as a first reference point,

[0027] c) determining the position of the needle holder by means of a sensor and determining the position of the needle tip of the biopsy needle from the position of the needle holder and the calculated total needle length,

[0028] d) automatically calculating the distance from the needle tip to the needle guide as a second reference point,

[0029] e) repeating steps c) and d) several times.

[0030] For this purpose, it should be noted that the possible movement vectors of the needle holder in the biopsy unit are known. The needle holder can only be moved along the movement vectors (or "movement directions"). Since the biopsy needle is rigid, the needle tip moves correspondingly when the needle holder is moved. Thus, if the position of the reference point at the needle holder is known and, in addition, if the distance of the needle tip to the reference point is known, the position of the needle tip can be determined precisely along the movement vectors and thus also in space.

[0031] The device according to the application serves to determine the position of the needle tip of a biopsy needle automatically, which is accommodated in a needle holder and can be moved on a longitudinal axis of the biopsy unit for a biopsy by the biopsy unit and is guided by means of a needle guide. The device comprises the following components:

[0032] - optionally: a sensor for recognizing the positioning of the biopsy needle in the needle holder,

[0033] - a determination unit designed to determine, by means of a sensor, at least the position of the tip of the biopsy needle,

[0034] - a calculation unit designed to automatically calculate the distance from the tip to the reference point,

[0035] Preferably: a data interface designed to output the distance, in particular in the form of a needle length or a position of the tip.

[0036] The functions of the components of the device have already been described above. The device is preferably designed to implement the method according to the application.

[0037] The mammography system according to the application comprises a device according to the application and / or is designed to perform the method according to the application.

[0038] The application can in particular be implemented in the form of a computer unit with suitable software. The computer unit can for this purpose have one or more cooperating microprocessors, etc. In particular, the microprocessor can be implemented in the computer unit in the form of suitable software program portions. A software-based implementation scheme has the advantage that computer units already used to date can also be retrofitted in a simple manner by means of a software or firmware upgrade in order to work in the manner according to the application. In this respect, the object is also achieved by a corresponding computer program product, which has a computer program which can be loaded directly into the memory means of the computer unit, which has program segments in order to carry out all the steps of the method according to the application when the program is executed in the computer unit. In addition to the computer program, such a computer program product can comprise additional components, such as file assemblies and / or additional parts, and also hardware components, such as hardware keys for using the software (dongles, etc.), if appropriate.

[0039] A computer-readable medium, such as a memory stick, a hard disk or other removable or fixedly installed data carriers, can be used for transmission to the computer unit and / or storage at or in the computer unit, on which computer-readable medium program segments of the computer program which can be read and executed by the computer unit are stored.

[0040] Further particularly advantageous design schemes and refinements of the application result from the following description, wherein a claim of one claim category can also be refined into another claim category, similar to the claims and description parts, and individual features of different embodiments or variants can also be combined into new embodiments or variants, in particular.

[0041] Within the scope of the method or for the preferred apparatus, a preferred sensor for determining the position of the needle tip of the biopsy needle is a capacitive sensor, an inductive sensor, an optical sensor or an acoustic sensor. The sensor can measure the position of the needle tip or the position of the needle holder directly. Preferably, however, the sensor measures the position of the needle tip directly. The measurement is preferably made by means of a sensor at or in the needle guide device.

[0042] Alternatively or additionally, it is preferred that an optical sensor monitors whether the biopsy needle has reached a preset position. It should be noted here that the needle tip is always moved in the direction of movement of the needle holder. An optical sensor, for example a grating, can determine when the needle tip has reached a certain point in the direction of movement. Since the biopsy needle is usually metallic and, if necessary, also magnetic, the presence of the needle at the certain point can be determined by means of an inductive sensor or a capacitive sensor. A camera is preferably also used as a sensor, as will be described in more detail below.

[0043] Preferably, the position of the needle holder is measured at least in the case where the needle tip is in the patient and / or after a certain needle length or in addition to the (direct) measurement of the needle tip. A preferred sensor for this is a capacitive sensor, an inductive sensor, an optical sensor or an acoustic sensor. It is also possible to query a potentiometer or to measure its state by means of a sensor. It is also possible to determine the position of the needle holder from the control preset for moving the needle holder. In addition to the (direct) measurement of the position of the needle tip, measuring the position of the needle holder has the advantage that the position of the needle tip can be determined even if the needle tip is in the patient.

[0044] Preferably, the presence of the needle tip in the region of the needle guide device is first checked. If the needle tip has been identified there, it is not necessarily necessary to continue to determine the position of the needle tip. Since the needle length is known (determined automatically or because the inserted needle is known and verified) and the direction of movement of the needle is known (in the direction of movement), the determination of the position of the needle holder can unambiguously determine the position of the needle tip.

[0045] Preferably, the movement of the needle holder is read from a scale or determined by means of a scale or the state of the slide of the biopsy unit is determined here. By means of a detection of counted increments in the calculation or of analog values in the calculation when using a scale, for example, starting from the introduction of the needle into the needle probe, or when applying an analog measuring system (for example a potentiometer), or by reading fixed positions, the state can be detected by means of a control system or can also be visualized by displaying it to the user at a display. Furthermore, the position or the needle length can be evaluated by a programmable control system, if necessary to correct the correct position or to trigger an error display. For example, by detecting several positions, for example 3 preset lengths, a suitable detection with lower accuracy can be achieved.

[0046] Preferably, the length of the biopsy needle is measured before the biopsy and after the needle has been positioned in the needle holder. This is preferably done by recording an image of the biopsy needle in the holder (particularly using a camera) and evaluating that image. Alternatively, the position of the needle tip at the needle guide can be determined, and the needle holder can then be moved toward the needle guide until a stop point (in the absence of a patient). As described above, measuring the length of the biopsy needle has the advantage of avoiding errors caused by deviations between the given needle length and the actual needle length when determining the position of the needle tip.

[0047] Preferably, the position of the biopsy needle tip is determined using an optical sensor, preferably a camera (2D or 3D). Preferably, an image of the biopsy needle is recorded from a fixed recording position having a predetermined distance from the needle, and the length of the biopsy needle is calculated by locating the biopsy needle and needle holder in the image and converting the length of the biopsy needle in the image (e.g., by counting pixels) into the true length of the biopsy needle using a predetermined function (e.g., triangulation or a function to compensate for known distortions in the image). Preferably, the thickness of the biopsy needle in the image is also converted into the true thickness of the biopsy needle using a predetermined function (e.g., also by counting pixels). This has the advantage that the length of the biopsy needle can be determined with very little effort and without needing to move to a precise location. It should be noted that needles exist only in forms of (known) distinctly different length classes. Therefore, it is not usually necessary to determine the length with millimeter-level precision.

[0048] Preferably, in one embodiment of the method, the presence of the biopsy needle in the needle holder is determined by means of a sensor. This sensor can be, for example, a switch that is activated if the biopsy needle is in the needle holder and deactivated if the biopsy needle is not in the needle holder. Upon insertion of the biopsy needle, movement of the needle holder is prevented under preset conditions, particularly when the distance from the needle tip to the fixed reference point exceeds a preset limit. This prevents the biopsy needle from protruding through the target area in the patient.

[0049] Preferably, after positioning the biopsy needle in the needle holder, and preferably also after optionally checking that the biopsy needle is inserted in the needle holder, the following steps are performed:

[0050] - Record images of the biopsy needle and needle holder.

[0051] - Segment the image,

[0052] - Perform at least a contour probe of the biopsy needle.

[0053] - Count the pixels that have been segmented into biopsy needles.

[0054] - The actual length of the biopsy needle is calculated using the length of the biopsy needle in the image and a preset formula, and preferably, the actual thickness of the biopsy needle is also calculated using the thickness of the biopsy needle in the image and a preset formula.

[0055] - Preferably, the calculated values ​​are output in the form of an image with the corresponding dimensions.

[0056] The images are preferably recorded by a camera, as described above. It is important here that the biopsy needle is fully recorded, and at least the portion of the needle holder tightly containing the biopsy needle is recorded.

[0057] Image segmentation is known in the prior art. This is preferably performed using a machine learning-enabled model trained to identify biopsy needles and needle holders in the image. After segmentation, it is known which pixels in the image represent biopsy needles and which represent needle holders.

[0058] Contour probing is known in the prior art for segmented elements (i.e., biopsy needles). Preferably, the contour probing is performed using the minimum rectangle method, also known in the prior art. Here, the smallest rectangle is found around the relevant contour. In this way, the pixels representing the biopsy needle are separated.

[0059] The separated pixels can then be counted. In the simplest case, the recording is adjusted so that the needle extends precisely in the X or Y direction of the image. However, a tilted view is also perfectly feasible. Preferably, the counting is performed at least in the vertical direction. The counting is used to determine the length of the biopsy needle in the image. Preferably, pixels are also counted in the horizontal direction as well. This is used to determine the thickness of the biopsy needle in the image.

[0060] If the number of pixels is known, the actual length of the biopsy needle is calculated. Because the biopsy needle has a different length in the image than in reality, but this length is scaled only by a known (or obtainable) function, the actual length can be calculated using the length of the biopsy needle in the image and a predefined formula. In the case of a linear relationship, the actual length will be L = aB, where a is a factor and B is the length in the image. Preferably, the actual thickness of the biopsy needle is also calculated using the thickness of the biopsy needle in the image and a predefined formula. This can be done accordingly, just as with the length. However, it should be noted that the biopsy needle is usually angled. This affects not only the length calculation but also the thickness calculation (in this case, the needle is slightly tapered). However, in practice, this has only a small effect, as the angled position can be compensated for by appropriately selecting a function for the calculated length. Regarding the thickness, a specific point of the needle (e.g., the tip) can be selected.

[0061] The calculated values ​​can then be displayed or stored in a log file, for example. Preferably, an image of the needle is output in the corresponding dimensions.

[0062] According to a preferred embodiment of the invention, the needle holder is additionally examined to identify characteristics that disclose its manufacturer. Preferably, this involves searching for symbols, particularly in the form of logos and / or characters, at the location of the needle holder in the image. The found symbols are then compared to a list consisting of symbols. This is used to better verify that the correct needle is being used.

[0063] A preferred device includes an optical sensor designed and configured to record images of the needle holder and the inserted biopsy needle. Additionally, the device includes a length determination unit designed to determine the length of the biopsy needle. Particularly preferably, the length determination unit is designed to locate the biopsy needle and needle holder in the image and convert the length of the biopsy needle in the image to the actual length of the biopsy needle using a preset function. Preferably, the length determination unit is also designed to convert the thickness of the biopsy needle in the image to the actual thickness of the biopsy needle using a preset function.

[0064] According to a preferred embodiment of the invention, before inserting the biopsy needle into the needle holder, an identification code, such as a QR code, label, string, NFC information, or barcode, is scanned on the biopsy needle or its packaging. The scanned information is then compared with preset information regarding the desired needle type. If the identification code indicates that it is not the desired needle type, a warning message is issued. This has the advantage of preventing accidental tearing of the sterile needle's packaging. Alternatively or additionally, insertion of the biopsy needle into the needle holder is prevented. This has the advantage of providing additional protection against the use of incorrect needles beyond human attention.

[0065] Preferred devices include sensors designed to detect the needle tip at the needle guide and sensors designed to determine the position of the needle holder. Preferably, the computing unit is designed to automatically calculate the distance from the needle tip to a fixed reference point in space, preferably to a point at the needle holder, based on the measured position of the needle tip at the needle guide and the position of the needle holder.

[0066] It is desirable to determine only the needle length in order to check if the correct biopsy needle is present. A preferred method here is to automate the determination of the biopsy needle length. This method includes the following steps:

[0067] - Biopsy needles are provided (in their packaging or in the needle holder).

[0068] - Using optical sensors, especially cameras or barcode readers, images of the biopsy needle (in the needle holder or in its packaging) are recorded, or the needle's NFC information is recorded using sensors.

[0069] - Determine the needle length from the sensor information, especially from the image information.

[0070] - Output pin length (output as information to the operator or in the form of control commands).

[0071] Here, two implementations of the method are particularly preferred. On one hand, the method allows reading of a code (e.g., a barcode or QR code) on the biopsy needle or packaging and checking whether the correct (packaged) biopsy needle has been selected. This implementation prevents incorrect biopsy needles from being inserted in the wrong manner, in which case the biopsy needle must be discarded because it is no longer sterile. Therefore, this implementation prevents unnecessary costs.

[0072] Another preferred embodiment allows for the automatic determination of the needle length from the image when the needle is inserted. This has already been described above.

[0073] First, a biopsy needle is provided. The biopsy needle may be present in its packaging (for one preferred method) or may already be present in a needle holder (for another preferred method).

[0074] Then, an image of the biopsy needle is recorded. In one preferred method, this can be an image from a barcode or QR code reader; in another preferred method, this can be an image from a camera as described above.

[0075] Then, the needle length can be determined from the image. In a preferred method, the needle length can be read directly from the encoded information; in another preferred method, the needle length can be read by evaluating image information (e.g., counting pixels), as described above.

[0076] The obtained needle length can then be output as information to the operator or as a control command.

[0077] A preferred device for automatically determining the length of a biopsy needle, particularly a device utilizing the above-described method, includes the following components:

[0078] - Provision of biopsy needles (in their packaging or in the needle holder).

[0079] - Optical sensors, especially cameras or barcode readers, designed to record images of biopsy needles.

[0080] - A length determination unit, designed to determine the needle length from image information of an image.

[0081] - Data interface, which is designed to output the needle length (either as information to the operator or as a control command).

[0082] The functions of the components of the device have been described above. This device is preferably designed for implementing the method according to the invention.

[0083] Preferred mammography systems include the device and / or are designed to perform preferred methods.

[0084] The preferred sensors for preferred methods or preferred devices used for length measurement have already been mentioned above. The same applies to monitoring whether the biopsy needle has reached a preset position.

[0085] The preferred method for measuring needle length is to record the biopsy needle in the needle holder in an image (especially by means of a camera) and evaluate the image. Alternatively, the position of the needle tip at the needle guide can be determined, and the needle holder can then be moved toward the needle guide until a stop point (in the absence of a patient). As described above, measuring the length of the biopsy needle has the advantage of avoiding errors caused by the deviation between the preset needle length and the actual needle length when determining the position of the needle tip.

[0086] As described, the needle length is preferably determined by an optical sensor, preferably a camera (2D or 3D). Preferably, an image of the biopsy needle is recorded from a fixed recording position having a predetermined distance from the needle, and the needle length is calculated by locating the biopsy needle and needle holder in the image and converting the needle length in the image (e.g., by counting pixels) into the true needle length using a predetermined function (e.g., triangulation or a function to compensate for known distortions in the image). Preferably, the needle thickness in the image is also additionally converted into the true needle thickness using a predetermined function (e.g., also by counting pixels). This has the advantage of determining the needle length with very little effort and without needing to move to a precise location. It should be noted that needles exist only in forms of (known) distinctly different length classes. Therefore, it is not always necessary to determine the length with millimeter-level precision.

[0087] Preferably, after positioning the biopsy needle in the needle holder, and preferably also after optionally checking that the biopsy needle is inserted into the needle holder, the following steps are performed:

[0088] - Record images of the biopsy needle and needle holder.

[0089] - Segment the image,

[0090] - Perform at least a contour probe of the biopsy needle.

[0091] - Count the pixels that have been segmented into biopsy needles.

[0092] - The actual length of the biopsy needle is calculated using the length of the biopsy needle in the image and a preset formula, and preferably, the actual thickness of the biopsy needle is also calculated using the thickness of the biopsy needle in the image and a preset formula.

[0093] - Preferably, the calculated values ​​are output in the form of an image with the corresponding dimensions.

[0094] The images are preferably recorded by a camera, as described above. It is important here that the biopsy needle is fully recorded, and at least the portion of the needle holder tightly containing the biopsy needle is recorded.

[0095] Image segmentation is known in the prior art. This is preferably performed using a machine learning-enabled model trained to identify biopsy needles and needle holders in the image. After segmentation, it is known which pixels in the image represent biopsy needles and which represent needle holders.

[0096] Contour probing of segmented elements (i.e., biopsy needles) is known in the prior art. Preferably, the contour probing is performed using the minimum rectangle method, also known in the prior art. Here, the smallest rectangle is found around the relevant contour. In this way, the pixels representing the biopsy needle are separated.

[0097] The separated pixels can then be counted. In the simplest case, the recording is adjusted so that the needle extends precisely in the X or Y direction of the image. However, a tilted view is also perfectly feasible. Preferably, the counting is performed at least in the vertical direction. The counting is used to determine the length of the biopsy needle in the image. Preferably, pixels are also counted in the horizontal direction as well. This is used to determine the thickness of the biopsy needle in the image.

[0098] If the number of pixels is known, the actual length of the biopsy needle is calculated. Because the biopsy needle has a different length in the image than in reality, but this length is scaled only by a known (or obtainable) function, the actual length can be calculated using the length of the biopsy needle in the image and a predefined formula. In the case of a linear relationship, the actual length will be L = aB, where a is a factor and B is the length in the image. Preferably, the actual thickness of the biopsy needle is also calculated using the thickness of the biopsy needle in the image and a predefined formula. This can be done accordingly, just as with the length. However, it should be noted that the biopsy needle is usually angled. This affects not only the length calculation but also the thickness calculation (in this case, the needle is slightly tapered). However, in practice, this has only a small effect, as the angled position can be compensated for by appropriately selecting a function for the calculated length. Regarding the thickness, a specific point of the needle (e.g., the tip) can be selected.

[0099] The calculated values ​​can then be displayed or stored in a log file, for example. Preferably, an image of the needle is output in the corresponding dimensions.

[0100] According to a preferred embodiment of the invention, the needle holder is additionally examined to identify characteristics that disclose its manufacturer. Preferably, this involves searching for symbols, particularly in the form of logos and / or characters, at the location of the needle holder in the image. The found symbols are then compared to a list consisting of symbols. This is used to better verify that the correct needle is being used.

[0101] As described above, the preferred device includes an optical sensor designed and configured to record images of the needle holder and the inserted biopsy needle. Additionally, the device includes a length determination unit designed to determine the length of the biopsy needle. Particularly preferably, the length determination unit is designed to locate the biopsy needle and needle holder in the image and convert the length of the biopsy needle in the image to the actual length of the biopsy needle using a preset function. Preferably, the length determination unit is also designed to convert the thickness of the biopsy needle in the image to the actual thickness of the biopsy needle using a preset function.

[0102] According to a preferred embodiment of the invention, before inserting the biopsy needle into the needle holder, an identification code, such as a QR code, label, string, NFC information, or barcode, is scanned at the biopsy needle or on its packaging. The scanned information is then compared with preset information regarding the desired needle type. If the identification code indicates that it is not the desired needle type, a warning message is issued. This has the advantage of preventing accidental tearing of the sterile needle packaging. Alternatively or additionally, insertion of the biopsy needle into the needle holder is prevented. This has the advantage of providing additional protection against the use of incorrect needles beyond human attention.

[0103] Preferably, a KI-based method (KI: "Künstliche Intelligenz" - Artificial Intelligence) is used in the method according to the invention. Artificial intelligence is based on the principles of machine learning and is typically performed using algorithms that have been trained and possess learning capabilities. The term "Machine Learning" is commonly used to describe machine learning, which also includes the principles of "Deep Learning." In particular, detecting biopsy needles in images is one task of such a system.

[0104] Preferably, the components of the present invention exist as a "cloud service." This cloud service is used for data processing, particularly with the aid of artificial intelligence, but it can also be a service based on traditional algorithms or a service evaluated by humans in the background. Generally, a cloud service (hereinafter referred to as the "cloud") is IT infrastructure in which storage space or computing power and / or application software are provided via a network. Communication between the user and the cloud is conducted via data interfaces and / or data transmission protocols. Where this is present, it is particularly preferred that the cloud service provides not only computing power but also application software.

[0105] Within the scope of the preferred method, data obtained within the scope of this invention is provided to a cloud service via a network. The cloud service includes computing systems that typically do not include the user's local computer. This method can be implemented using an instruction set within the network. The data computed in the cloud is then sent back to the user's local computer via the network. Attached Figure Description

[0106] The present invention will now be described in detail again with reference to the accompanying drawings and embodiments. Here, in different figures, the same parts are given the same reference numerals. The figures are generally not to scale. The drawings show:

[0107] Figure 1 A rough schematic diagram of a preferred mammography system with preferred equipment is shown.

[0108] Figure 2 The biopsy unit is shown.

[0109] Figure 3 A preferred sensor device is shown at the needle holder equipped with a biopsy needle.

[0110] Figure 4 Another preferred sensor device is shown at the needle holder equipped with the biopsy needle.

[0111] Figure 5 This demonstrates how to measure needle length using a camera.

[0112] Figure 6 The flowchart illustrates the process of this method.

[0113] Figure 7 This shows how to scan a barcode to determine the needle type. Detailed Implementation

[0114] exist Figure 1 The diagram illustrates, in a illustrative and rough schematic form, a mammography system 1 in the form of a tomography system 1. Relative directions, such as "upper" and "lower," refer to the tomography system 1 as defined for operation. The tomography system 1 includes a tomography device 2 and a control unit 9.

[0115] The tomography apparatus 2 has a column 7 and a source detector device 3, which in turn includes an X-ray radiator 4 and a detector 5 having a detector surface 5.1. The column 7 stands upright on the ground during operation. The source detector device 3 is movably connected to the column, allowing the height of the detector surface 5.1, i.e., its distance from the ground, to be set to the patient's chest height.

[0116] The patient's chest O (shown schematically here) is placed on the detector surface 5.1 on its upper side as the examination object O. A pressure plate 6 is positioned above the chest O and detector surface 5.1, and is movably connected to the source detector device 3. For the examination, the chest O is compressed and simultaneously secured by lowering the pressure plate 6 onto the chest, such that pressure is applied to the chest O between the pressure plate 6 and detector surface 5.1. The contact surface of the pressure plate 6 facing the chest has a concave arch, causing the chest to convexly arch there, for example... Figure 4 , Figure 5 and Figure 6 As shown in the image.

[0117] X-ray radiator 4 and detector 5 are positioned opposite each other and configured such that detector 5 detects the X-ray radiation R emitted by the X-ray radiator after at least a portion of the X-ray radiation R has penetrated the patient's chest O. Here, X-ray radiator 4 can pivot relative to detector 5 within a range of ±50° around a basic position, in which it stands vertically above detector surface 5.1, by means of a rotating arm 8. The area to be recorded can be preset or limited by means of collimator C.

[0118] The control device 9 acquires the raw measurement data RD and sends control data SD to the tomography synthesis device 2 via a data interface. The control device is connected to a terminal 20, through which the user can issue commands to the tomography synthesis system 1 or retrieve measurement results. The control device 9 can be located in the same room as the tomography synthesis device 2, but it can also be located in an adjacent control room or at a greater spatial distance.

[0119] The device 10 according to the invention is used to automatically determine the position of the tip N of a biopsy needle 32, which is housed in a needle holder 31 and can be moved along the longitudinal axis of the biopsy unit 30 for biopsy to be performed, and is guided by means of a needle guide 33 (see...). Figure 2 The device includes a determination unit 11, a calculation unit 12, and a length determination unit 13. A sensor (not shown) for identifying the positioning of the biopsy needle 32 within the needle holder 31 is also preferred. The device is here located within a control unit. However, the device could also be useful in other locations, such as at the rotating arm 8, or elsewhere near the X-ray R, or even directly at the biopsy unit 30.

[0120] The determining unit 11 is used to determine the position of at least the tip N of the biopsy needle 32 by means of the sensor 35 (see the following figures).

[0121] The calculation unit 12 is used to automatically calculate the distance from the needle tip N to the reference point.

[0122] The length determination unit 13 is used to determine the length of the biopsy needle 32. Preferably, this is done by locating the biopsy needle 32 and the needle holder 31 in image B, and converting the length of the biopsy needle 32 in image B into the actual length of the biopsy needle 32 using a preset function. The length determination unit can also be additionally used to convert the thickness of the biopsy needle 32 in image B into the actual thickness of the biopsy needle 32 using a preset function.

[0123] Then the resulting image E is output via data interface 14.

[0124] Figure 2 A biopsy unit 30 with a needle holder 31 is shown, the needle holder 31 being mounted on a slide 36. A biopsy needle 32 is inserted into the needle holder 31, the biopsy needle being guided by a needle guide 33. Here, in order to extract a biopsy sample, the biopsy needle 32 has been introduced into the examination subject O, which is, in this case, a female breast O. Here, the breast O is located according to... Figure 1 The biopsy needle 32 has been moved through a hole in the compression plate 6 on the detector 5 of the mammography system 1. The double arrows indicate the possible directions of movement for the biopsy needle 32 and the needle holder 31.

[0125] Figure 3 and Figure 4 Shown in accordance with Figure 2 The preferred sensor device is located at the needle holder 31 of the biopsy unit 30, which is equipped with a biopsy needle 32. Two embodiments are shown, respectively, of a sensor 34 for monitoring the movement of the needle holder and a sensor 35 at the needle guide 33 for detecting the position of the needle tip N.

[0126] existFigure 3 In this design, a scale S is placed at the needle holder, the position of which is monitored by an optical sensor 34. This allows for very precise determination of the position of the needle holder 31. Because the structure of the needle holder 31 and the biopsy needle 32 is rigid, the position of the biopsy needle 32 can be directly inferred from the position of the needle holder 31. However, for safety, the needle tip N is still determined at the needle holder 35. This ensures that the determined position on the scale actually corresponds to the (determined) position of the needle tip N. For example, if an incorrect needle length is selected, this will be detected. The needle holder 31 can then move to a preset rear position where the needle tip N has not yet been detected at the needle holder 33, and then slowly move forward until the sensor 35 at the needle holder 33 detects the needle tip N. Now the position of the scale S can be directly correlated with the position of the needle tip N, and even the needle length can be determined. The sensor shown here can be, for example, a capacitive sensor, an inductive sensor, or an acoustic sensor.

[0127] exist Figure 4 In this design, a scale S formed by shadows is placed at the needle holder, the position of which is monitored by an optical sensor 34. This allows for very precise determination of the position of the needle holder 31, especially when the sensor 34 has spatial resolution. For safety, the needle tip N at the needle holder 35 is also determined using an optical sensor 35 in the form of a grating in this example.

[0128] Figure 5 The image illustrates the use of an optical sensor 35 in the form of a camera to determine the position of the biopsy needle 32's tip. In this example, an image B of the biopsy needle 32 is recorded from a fixed recording position having a preset distance from the biopsy needle 32. The length of the biopsy needle 32 is then calculated from the image by locating the biopsy needle 32 and needle holder 31 in image B and converting the length of the biopsy needle 32 in image B to its actual length using a preset function.

[0129] This is preferably done by means of the following steps:

[0130] - Image B of the recorded biopsy needle 32 and needle holder 31,

[0131] - Segmenting image B, preferably using a machine learning-enabled model trained to identify the biopsy needle 32 and needle holder 31 in image B.

[0132] - Perform contour probing with at least 32 biopsy needles, preferably using the minimum rectangle method.

[0133] - Preferably, the pixels that have been segmented into biopsy needles 32 are counted at least in the vertical direction to determine the length of the biopsy needles 32 in image B, and preferably additionally, the pixels are counted in the horizontal direction to determine the thickness of the biopsy needles 32 in image B.

[0134] - The actual length of the biopsy needle 32 is calculated using the length of the biopsy needle 32 in image B and a preset formula, and preferably, the actual thickness of the biopsy needle 32 is also calculated using the thickness of the biopsy needle 32 in image B and a preset formula.

[0135] - Preferably, the calculated values ​​are output in the form of an image B with the corresponding dimensions.

[0136] Figure 6 As shown in the block diagram, it is used to rely on... Figure 2 The flowchart describes a method for automatically determining the position of the biopsy needle tip in a biopsy unit.

[0137] First, position the biopsy needle 32 inside the needle holder 31 (on the left side).

[0138] Then, in step I, firstly as about Figure 5 The length L of the biopsy needle 32 is determined from the image as described.

[0139] In step II, the position of at least the tip N of the biopsy needle 32 at the needle guide device 33 is determined by means of the sensor 35.

[0140] In step III, the distance from the needle tip N to the needle guide device 33, which serves as a reference point, is automatically calculated. Here, the position of the needle holder 31 is determined by means of the sensor 34, and its precise position is inferred by means of the obtained length L of the biopsy needle 32.

[0141] Figure 7 The procedure involves scanning a barcode to determine the needle type. Here, before inserting the biopsy needle 32 into the needle holder 31, a barcode is scanned on the biopsy needle 32 or on its packaging. The scanned information is then compared with preset information regarding the desired needle type. If barcode C indicates that it is not the desired needle type, a warning message is issued.

[0142] Finally, it should be pointed out again that the invention described in detail above is merely an embodiment, and these embodiments can be modified by those skilled in the art in entirely different ways without departing from the scope of the invention. Furthermore, the use of the indefinite article "a" does not preclude the existence of multiple features. Similarly, the term "unit" does not preclude the possibility that the component involved is composed of multiple interacting sub-components that may optionally be spatially distributed. The term "multiple" should be interpreted as "at least one." Nouns and pronouns relating to persons in this invention generally do not specify a particular gender.

Claims

1. A method for automatically determining the position of the tip (N) of a biopsy needle (32), the biopsy needle (32) being disposed in a needle holder (31) and movable along the longitudinal axis of a biopsy unit (30) for biopsy to be performed, and guided by means of a needle guide (33), the method comprising the steps of: - Position the biopsy needle (32) in the needle holder (31), - The position of at least the tip (N) of the biopsy needle (32) is determined by means of a sensor (35). - Automatically calculate the distance from the needle tip (N) to the reference point.

2. The method according to claim 1, wherein the position of the tip (N) of the biopsy needle (32) is determined by means of a capacitive sensor, an inductive sensor, an optical sensor or an acoustic sensor, preferably by means of a sensor (35) at or in the needle guide device (33) and / or an optical sensor (35) that monitors whether the biopsy needle (32) has reached a preset position.

3. The method according to any one of the preceding claims, wherein the position of the needle holder (31) is measured at least when the needle tip (N) is inside the patient and / or after the needle length (L) is determined, particularly by means of a capacitive sensor, an inductive sensor, an optical sensor or an acoustic sensor, or from the state of a potentiometer or a control preset, preferably wherein the movement of the needle holder (31) is read from a scale (S) or the movement of the needle holder is determined by means of a scale (S), or the state of the slide (36) of the biopsy unit (30) is determined.

4. The method according to any one of the preceding claims, wherein the length (L) of the biopsy needle (32) is measured before the biopsy and after the biopsy needle (32) is positioned in the needle holder (31), preferably by recording the biopsy needle (32) in the needle holder (31) in an image (B) and evaluating the image (B), or by determining the position of the needle tip (N) at the needle guide (33) and subsequently moving the needle holder (31) toward the needle guide (33) until a stop point.

5. The method according to claim 4, wherein the position of the tip (N) of the biopsy needle (32) is determined by means of an optical sensor (35), preferably a camera, wherein an image (B) of the biopsy needle (32) is recorded from a fixed recording position having a preset distance from the biopsy needle (32) and the length (L) of the biopsy needle (32) is calculated by finding the biopsy needle (32) and the needle holder (31) in the image (B) and converting the length (L) of the biopsy needle (32) in the image (B) into the true length (L) of the biopsy needle (32) by means of a preset function, and preferably also converting the thickness of the biopsy needle (32) in the image (B) into the true thickness of the biopsy needle (32) by means of a preset function.

6. The method according to any one of the preceding claims, wherein the presence of the biopsy needle (32) in the needle holder (31) is determined by means of a sensor, and in the case of insertion of the biopsy needle (32), under a preset condition, especially when the distance from the needle tip (N) to the fixed reference point exceeds a preset limit value, the movement of the needle holder (31) is prevented.

7. The method according to claim 5 or 6, wherein after positioning the biopsy needle (32) in the needle holder (31) and preferably also after optionally checking whether the biopsy needle (32) is inserted in the needle holder (31), the following steps are performed: - Record images (B) of the biopsy needle (32) and the needle holder (31). - Segment the image (B), preferably by means of a machine learning-enabled model trained to identify the biopsy needle (32) and needle holder (31) in the image (B). - Preferably, contour probing is performed on at least the biopsy needle (32) using the minimum rectangle method. - Preferably, the pixels that have been segmented into biopsy needles (32) are counted at least in the vertical direction to determine the length (L) of the biopsy needles (32) in the image (B), and preferably additionally, the pixels are counted in the horizontal direction to determine the thickness of the biopsy needles (32) in the image (B). - The actual length (L) of the biopsy needle (32) is calculated using the length (L) of the biopsy needle (32) in the image (B) and a preset formula, and preferably, the actual thickness of the biopsy needle (32) is also calculated using the thickness of the biopsy needle (32) in the image (B) and a preset formula. - Preferably, the calculated values ​​are output in the form of an image (B) with the corresponding dimensions.

8. The method according to any one of claims 5 to 7, wherein the needle holder (31) is additionally examined to determine the characteristics of its manufacturer, in particular, wherein symbols, in particular in the form of signs and / or characters, are searched for at the location of the needle holder (31) in the image (B), and the found symbols are compared with a list consisting of symbols.

9. The method according to any one of the preceding claims, wherein before inserting the biopsy needle (32) into the needle holder (31), an identification code, preferably a QR code, label, string, NFC information or barcode, is scanned at the biopsy needle (32) or at the packaging of the biopsy needle (32), the scanned information is compared with preset information about the desired needle type, and a warning message is issued and / or insertion of the biopsy needle into the needle holder (31) is prevented if the barcode (C) indicates that it is not the desired needle type.

10. An apparatus (10) for automatically determining the position of the tip (N) of a biopsy needle (32), the biopsy needle (32) being disposed in a needle holder (31) and movable along the longitudinal axis of a biopsy unit (30) for biopsy, and guided by means of a needle guide (33), the apparatus (10) comprising: - Optionally: a sensor for identifying the positioning of the biopsy needle (32) in the needle holder (31), - Determination unit (11), the determination unit being designed to determine the position of at least the tip (N) of the biopsy needle (32) by means of a sensor (35). - Calculation unit (12), which is designed to automatically calculate the distance from the needle tip (N) to the reference point.

11. The device (10) according to claim 10, the device comprising an optical sensor (35) designed and configured to record an image (B) of the needle holder (31) and the inserted biopsy needle (32), and the device comprising a length determination unit (13) designed to determine the length (L) of the biopsy needle (32), preferably by locating the biopsy needle (32) and the needle holder (31) in the image (B), and converting the length (L) of the biopsy needle (32) in the image (B) into the actual length (L) of the biopsy needle (32) by means of a preset function, and preferably also converting the thickness of the biopsy needle (32) in the image (B) into the actual thickness of the biopsy needle (32) by means of a preset function.

12. The device (10) according to claim 10 or 11, the device comprising a sensor (35) designed to detect the needle tip (N) at the needle guide (33) and a sensor (34) designed to determine the position of the needle holder (31), preferably wherein the computing unit (12) is designed to automatically calculate, based on the measured position of the needle tip (N) at the needle guide (33) and the position of the needle holder (31), the distance from the needle tip (N) to a fixed reference point in space, preferably the distance to a point at the needle holder (31).

13. A mammography system (1), the mammography system comprising the device (10) according to any one of claims 10 to 12 and / or designed to perform the method according to any one of claims 1 to 9.

14. A computer program product comprising instructions that, when executed by a computer, cause the computer to perform the steps of the method according to any one of claims 1 to 9.

15. A computer-readable storage medium comprising instructions that, when executed by a computer, cause the computer to perform the steps of the method according to any one of claims 1 to 9.

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