JP4835245B2 - Cardiac diagnostic imaging equipment - Google Patents

Description

  The present invention provides a circulation in which an image diagnosis is performed on a blood vessel of a subject by displaying an angiographic X-ray image and an IVUS image taken by an ultrasonic blood vessel endoscope (hereinafter also referred to as IVUS) side by side. The present invention relates to a diagnostic imaging apparatus. More specifically, when an IVUS probe (also referred to as an ultrasonic probe or an ultrasonic catheter) is inserted into a region of interest in the body of a subject and an IVUS image inside the blood vessel is imaged by the sensor portion of the probe, the blood vessel of the region of interest The present invention relates to a cardiovascular diagnostic imaging apparatus that displays X-ray images including contrast images side by side.

  In the diagnosis of the circulatory organ, a contrast medium is injected into a blood vessel in the region of interest of the subject, an X-ray image is taken by an X-ray examination apparatus (X-ray TV apparatus, X-ray CT apparatus), Diagnosis is performed by observing the projected angiographic image.

  In addition, in order to observe the blood vessel of the region of interest from the viewpoint from the inside of the blood vessel, an ultrasonic image signal obtained by inserting an IVUS probe into the blood vessel of the region of interest and transmitting / receiving ultrasonic waves from the sensor portion near the probe tip. Based on the above, a diagnosis is also made by displaying an IVUS image on the screen of a display device. When making a diagnosis with IVUS images, it is important to know exactly what part of the blood vessel the IVUS image displayed on the screen is, but this is enough to gain clinical experience and familiarity with IVUS testing. It was difficult to discriminate without a doctor.

  Therefore, recently, while performing X-ray imaging of a region of interest, an IVUS probe is inserted into a blood vessel to observe an IVUS image, and an IVUS probe image is simultaneously aligned with an angiographic image displayed in the X-ray image on the screen. By observing with, a diagnostic apparatus for circulatory organs is disclosed in which the position of the IVUS probe tip in the blood vessel can be confirmed and the IVUS image in the blood vessel at that position can be observed (Patent Document) 1, see Patent Document 2).

In this way, by using the cardiovascular diagnostic apparatus that can simultaneously observe the X-ray image and the IVUS image, the position of the stenosis site of the blood vessel in the subject can be accurately identified. For example, it is useful when performing a treatment for expanding a stenosis site using a balloon catheter.
Japanese Patent Laid-Open No. 10-137238 JP-A-5-84248

  In many cases, a subject who needs to take an IVUS image has taken an X-ray image by angiography at least once in the past. In the case of a subject who has taken an angiographic X-ray image, when an IVUS image is newly taken, an X-ray image is taken again by angiography. As the exposure dose increases, it is also affected by side effects and the like due to the contrast agent, and the burden on the subject is large.

  Further, in the conventional cardiovascular diagnostic device described in the prior art, X-ray imaging is performed to track the position of the sensor portion of the IVUS probe from the start of IVUS image imaging to the end of imaging. Therefore, when imaging of an IVUS image starts, the subject continues to be exposed to X-rays continuously until imaging of the IVUS image is completed.

  In order to reduce the exposure dose of the subject, when an IVUS image is taken, an X-ray image need not be taken at all. However, in that case, only an IVUS image can be obtained. Unless it is a doctor who has experience and is familiar with IVUS examinations, it is difficult to always accurately grasp the imaging position of the IVUS image at each time point.

  Therefore, in the present invention, when an IVUS probe is inserted into a subject's blood vessel and an IVUS image is taken, the X-ray image of the contrasted blood vessel is not taken simultaneously, or even if it is taken simultaneously. An object of the present invention is to provide a cardiovascular diagnostic device that can suppress the X-ray exposure dose of a subject as much as possible and can accurately grasp the position of the sensor portion of the IVUS probe.

An image diagnosis apparatus for a circulatory organ according to the present invention, which has been made to solve the above problems, includes an IVUS image creation unit that creates an IVUS image based on an ultrasound image signal from a sensor portion of an IVUS probe inserted into a blood vessel of a region of interest. , An insertion length detection unit for detecting the insertion length of the IVUS probe, an X-ray image storage region for storing an X-ray image of the region of interest including a contrasted blood vessel image, and a region of interest read from the X-ray image storage region An image display control unit that displays the X-ray image and IVUS image side by side on the display screen, a blood vessel path extraction unit that extracts shape information of the blood vessel image displayed on the displayed X-ray image by image processing, and a display a position of the feature portion on at least two positions of the blood vessel image in X-ray images, the position is a reference point, respectively the feature portion of the vessel to cope with IVUS images are observed When specified by the pointing device, a reference point information storage unit for storing the coordinates of each reference point and the insertion length at the time of specifying each reference point in association with each other, and the coordinates of each specified reference point and each reference A probe position calculation unit that calculates the position of the sensor portion with respect to the insertion length of the IVUS probe based on the insertion length associated with the point and the shape information of the blood vessel image between the reference points, and the calculated sensor A position marker display unit that indicates the position of the part on the display screen is provided.

  Here, strictly speaking, the “insertion length” of the IVUS probe refers to the length from the body surface of the subject to the sensor portion (usually the probe tip position) of the IVUS probe inserted into the body. However, the length of the part inserted from the body surface does not necessarily have to be, for example, the length from the origin position to the sensor part when the probe is sent out from the origin position determined on the base side of the IVUS probe. Good. In short, it is sufficient that the length information can be used to know the length changed by the movement from the difference between the insertion length before and after the movement when the IVUS probe is moved in the body.

The “image processing” may be any process that can extract the shape information of the blood vessel image included in the X-ray image. For example, by utilizing the fact that the brightness of the contrasted blood vessel image is different from the brightness of the part other than the blood vessel, the pixel portion whose brightness is equal to or higher than the reference value is compared with the reference brightness value set in advance. A pattern recognition process for recognizing a vascular path may be used.
In addition, the “pointing device” may be any device that can specify a position on the display screen.

  According to the present invention, an X-ray image of a region of interest including a contrasted blood vessel image is stored in advance in the X-ray image storage region. The IVUS image creation unit obtains an ultrasound image signal by transmitting and receiving ultrasound from the sensor portion of the IVUS probe inserted into the blood vessel of the region of interest, and creates a current IVUS image based on the ultrasound image signal. At this time, the insertion length detection unit detects the insertion length of the IVUS probe inserted into the blood vessel. The image display control unit reads the X-ray image of the region of interest stored in advance in the X-ray image storage region, and displays the X-ray image along with the current IVUS image on the display screen. The blood vessel path extraction unit extracts the shape information of the blood vessel image displayed in the X-ray image displayed on the display screen by image processing. By extracting the shape of the blood vessel path on the display screen (a set of position coordinates of each point forming the blood vessel path), if any point on the blood vessel path is instructed on the screen thereafter by the pointing device, that point The position coordinates of can be recognized. Further, when two points are designated on the blood vessel path, all the position coordinates of each point on the blood vessel path sandwiched between the two points are also recognized. Therefore, the distance of the curve between the two points can also be calculated by a simple calculation process.

  The reference point information storage unit stores each reference point when positions on at least two blood vessel images on the X-ray image displayed on the display screen by an operator are designated as reference points by the pointing device. The coordinates and the insertion length at the time of designating each reference point are stored in association with each other. For the designation of the reference point at this time, a point where a characteristic part (for example, a branch point of a blood vessel) is observed in the IVUS image is selected. As a result, when a position corresponding to the reference point position is designated on the X-ray image by the pointing device, a characteristic part on the X-ray image (that is, a branch point of the blood vessel path) may be searched. The corresponding point can be easily specified.

  The probe position calculation unit calculates the insertion length of the IVUS probe based on the coordinates of the specified at least two reference points, the insertion length associated with each reference point, and the shape information of the blood vessel image between the reference points. The position of the sensor portion of the IVUS probe is determined. That is, the amount of change in insertion length when the sensor portion moves between two reference points is detected. On the other hand, the length between two reference points is obtained from the shape information of the blood vessel image extracted from the X-ray image. Calibration is performed by associating these length information, and thereafter, by detecting the insertion length, the position on the blood vessel image corresponding to each insertion length is calculated. Then, the position marker display unit displays the calculated position on the X-ray image so that the IVUS image and the position on the contrast blood vessel can be observed in correspondence with each other.

  In this way, by using an X-ray image taken in the past, an IVUS image and an X-ray image can be observed without taking a new X-ray image by exposing the subject to new X-ray exposure. In addition, the position of the currently displayed IVUS image is displayed with a marker on the X-ray image.

Another circulatory image diagnostic apparatus of the present invention, which has been made to solve the above problems, generates an IVUS image based on an ultrasonic image signal from a sensor portion of an IVUS probe inserted into a blood vessel of a region of interest. An image creation unit, an insertion length detection unit that detects the insertion length of an IVUS probe, an X-ray image creation unit that creates an X-ray image of a region of interest including a contrasted blood vessel image at the time of IVUS image creation, and creation An X-ray image storage unit for storing the X-ray image thus obtained in the X-ray image storage area, an image display control unit for displaying the X-ray image and the IVUS image created by the X-ray image creation unit side by side on the display screen, a vascular path extractor for extracting shape information of the blood vessel image that is displayed on the displayed X-ray image by image processing, the position der feature portion on the blood vessel image of the at least two positions in the displayed X-ray image Te, when the position of a characteristic portion of the vessel to cope with IVUS image is observed is designated by the pointing device as the reference point, respectively, corresponding to the insertion length of time specified coordinates and the reference point of each reference point An IVUS probe based on the reference point information storage unit to be stored, the coordinates of each designated reference point, the insertion length associated with each reference point, and the shape information of the blood vessel image between the reference points A probe position calculation unit that calculates the position of the sensor portion relative to the insertion length of the sensor, and a position marker display unit that displays the calculated position of the sensor portion on the display screen, so that the probe position calculation unit calculates the sensor position. After that, the X-ray image creation unit stops creating the X-ray image, and the image display control unit displays the X-ray image read from the X-ray image storage area.

  According to the present invention, the IVUS image creation unit obtains an ultrasound image signal by transmitting and receiving ultrasound from the sensor portion of the IVUS probe inserted into the blood vessel of the region of interest, and based on this, obtains the current IVUS image. Create At this time, the insertion length detection unit detects the insertion length of the IVUS probe inserted into the blood vessel. On the other hand, the X-ray image creation unit includes a contrasted blood vessel image by irradiating the subject with X-rays from the time when the IVUS probe is inserted to start creating an IVUS image (or from immediately before). X-ray imaging of the region of interest is performed to create an X-ray image. Then, the created X-ray image is displayed on the display screen. The X-ray image storage unit stores the X-ray image of the region of interest including the blood vessel image at this time in the X-ray image storage region. The image display control unit reads an X-ray image of the region of interest currently being photographed, and displays the X-ray image along with the current IVUS image on the display screen. The blood vessel path extraction unit extracts the shape information of the blood vessel image displayed in the X-ray image displayed on the display screen by image processing. By extracting the shape of the blood vessel path on the display screen (a set of position coordinates of each point forming the blood vessel path), if any point on the blood vessel path is instructed on the screen thereafter by the pointing device, that point The position coordinates of can be recognized. Further, when two points are designated on the blood vessel path, all the position coordinates of each point on the blood vessel path sandwiched between the two points are also recognized. Therefore, the distance of the curve between the two points can also be calculated by a simple calculation process.

  The reference point information storage unit stores each reference point when positions on at least two blood vessel images on the X-ray image displayed on the display screen are designated as reference points by the pointing device by an operator's input. And the insertion length at the time of designating each reference point are stored in association with each other. For the designation of the reference point at this time, a point where a characteristic part (for example, a branch point of a blood vessel) is observed in the IVUS image is selected. As a result, when a position corresponding to the reference point position is designated on the X-ray image by the pointing device, a characteristic part on the X-ray image (that is, a branch point of the blood vessel path) may be searched. The corresponding point can be easily specified.

  The probe position calculation unit calculates the insertion length of the IVUS probe based on the coordinates of the specified at least two reference points, the insertion length associated with each reference point, and the shape information of the blood vessel image between the reference points. The position of the sensor portion of the IVUS probe is determined. That is, the amount of change in insertion length when the sensor portion moves between two reference points is detected. On the other hand, the length between two reference points is obtained from the shape information of the blood vessel image extracted from the X-ray image. Calibration is performed by associating these length information, and thereafter, by detecting the insertion length, the position on the blood vessel image corresponding to each insertion length is calculated. Then, the position marker display unit displays the calculated position on the X-ray image so that the IVUS image and the position on the contrast blood vessel can be observed in correspondence with each other.

  After the sensor position is calculated by the probe position calculation unit, the X-ray image generation unit stops the X-ray image generation process and ends the X-ray irradiation to the region of interest. The image display control unit displays the X-ray image read from the X-ray image storage area, and displays a position marker indicating the current position of the sensor portion on the image.

According to the first invention, when an IVUS image is taken, an X-ray image is not taken at all by angiography, so that the subject is not newly exposed to X-rays.
According to the second invention, when an IVUS image is taken, an X-ray image is first taken by angiography, but calibration is performed by associating the insertion length of the IVUS probe with the contrasted angiogram. After that, since the X-ray irradiation can be terminated, the subsequent X-ray exposure can be suppressed.
In either case, the IVUS image can be observed while confirming the accurate position of the sensor portion on the contrasted blood vessel image.

(Means and effects for solving other problems)
Moreover, in the said invention, you may make it an insertion length detection part detect insertion length based on the insertion speed of IVUS probe, and the insertion continuation time by the insertion speed.

  According to this, the insertion length can be obtained from the product of the insertion speed of the IVUS probe and the insertion duration time depending on the insertion speed.

Further, in the above invention, the probe position calculation unit, when the position on the three or more of the blood vessel image is designated as a reference point, the coordinate of the two reference points adjacent across the sensor portion of the IVUS probe 2 one of the insertion length associated with the reference point, and, based on the shape information of the blood vessel image between the two reference points, the position of the sensor portion in between the two reference points on the insertion length of the IVUS probe It may be calculated accordingly .

  According to this, since the calculation is performed using the two nearest reference points, the position error can be reduced.

Hereinafter, an embodiment of an optical measurement device of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of a cardiovascular image diagnostic apparatus according to an embodiment of the present invention. The cardiovascular diagnostic imaging apparatus 1 according to the present invention can be roughly classified into an X-ray image measurement unit 10, an IVUS image measurement unit 20, and an image processing unit 30.

  Among these, the X-ray image measurement unit 10 includes an X-ray inspection apparatus (X-ray TV apparatus) or a configuration equivalent thereto. That is, the X-ray image measurement unit 10 includes an X-ray measurement optical system 13 including an X-ray source 11 and an X-ray detector 12, a control device (CPU), a storage device (ROM, RAM, HDD), and an image creation circuit. And a control system 14 for controlling the X-ray measurement optical system 13. As a part of the function of the control system 14, an X-ray image creation unit 15 and an X-ray image storage control unit 16 are included.

  The X-ray image creation unit 15 emits X-rays from the X-ray source 11 so as to include the region of interest A of the subject S, and sequentially sends video signals of the region of interest A from the X-ray detector 12, and the video Control is performed to create an X-ray image (moving image) based on the signal. The created X-ray image is sent to the image processing unit 30.

  The X-ray image storage control unit 16 performs control to store the X-ray image (moving image) created by the X-ray image creation unit 15 in the X-ray image storage area 17. The stored X-ray image can be read from the image processing unit 30 at any time (even after the X-ray irradiation is finished).

  The IVUS image measurement unit 20 includes an IVUS apparatus (an ultrasonic vascular endoscope apparatus) or a configuration equivalent to this. That is, the IVUS image measurement unit 20 includes an IVUS probe 21 to be inserted into the body of a subject, and an IVUS apparatus main body 22 that connects and controls the IVUS probe 21.

A sensor 21 a that acquires an ultrasonic image signal by transmitting and receiving ultrasonic waves is provided at the distal end portion of the IVUS probe 21.
The IVUS apparatus main body 22 includes a probe drive mechanism 23 that inserts the IVUS probe 21, an IVUS image creation unit 24 that creates an IVUS image, and an insertion length detection unit 25 that detects the length of the IVUS probe inserted into the body. It has.

  The probe drive mechanism 23 inserts the IVUS probe 21 into the body at an insertion speed set by the operator. It is possible to insert at a constant insertion speed, or to insert while adjusting the speed by the operator. Here, “insertion” includes the feeding operation and the drawing operation of the IVUS probe 21 by treating the time when the probe is fed into the blood vessel as the insertion in the positive direction and the time when the probe is pulled out as the insertion in the negative direction. .

  The IVUS image creation unit 24 performs control to create an IVUS image in the blood vessel based on the ultrasonic image signal sent from the sensor 21a every moment. The created IVUS image (moving image) is sent to the image processing unit 30.

The insertion length detection unit 24 monitors the insertion speed of the IVUS probe 21 and the insertion duration time at the insertion speed using a speedometer and a clock (not shown), calculates the product of the insertion speed and the insertion duration time, By accumulating this, control is performed to detect the insertion length at each time point.
Specifically, for example, the insertion speed is measured and the time is measured using a known instrument such as a potentiometer that measures the rotational movement amount (rotation speed) of the roller per unit time by bringing the IVUS probe into contact with the roller. To determine the insertion length.

The image processing unit 30 includes a computer device having a hardware configuration including a mouse 31 as an input device, a display 32 as a display device, a control device (CPU) 33, and a storage device 34 (ROM, RAM, HDD). Is done.
The functions and processes executed by the control device 33 and the storage device 34 of the image processing unit 30 will be described in blocks for each function. The control device 33 includes the image display control unit 41, the blood vessel path extraction unit 42, and the reference point information storage unit. 43, a probe position calculation unit 44, and a position marker display unit 45, and the storage device 34 includes a blood vessel path storage area 51 and a reference point information storage area 52.

  The image display control unit 41 is further divided into an X-ray image display control unit 41a and an IVUS image display control unit 41b. The X-ray image display control unit 41a performs control to display the X-ray image 32a on the display 32 by one of the following two methods depending on the situation. That is, first, the X-ray image creation unit 15 performs control to display the X-ray image 32a currently being created in real time. Secondly, control is performed to display the X-ray image 32a stored in the X-ray image storage area 17 in advance.

The IVUS image display control unit 41b performs control so that the IVUS image creation unit 24 displays the IVUS image 32b currently being created on the display 32 in real time.
Then, the image display control unit 41 controls the X-ray image display control unit 41a and the IVUS image display control unit 41b so that the X-ray image 32a and the IVUS image 32b are displayed side by side on the display 32. Control. Further, when it is necessary to switch the image display control unit 41 to suppress the exposure dose to the subject, the X-ray image creation unit 15 creates the X-ray image 32a displayed by the X-ray image display control unit 41a. Control is performed to switch from the real-time X-ray image to the X-ray image stored in the X-ray image storage area 17.

  The blood vessel path extraction unit 42 performs control to extract the shape information of the blood vessel image displayed on the X-ray image 32a displayed on the display 32 by image processing based on pattern recognition. In other words, the brightness of the contrasted blood vessel portion of the X-ray image 32a is projected to be different from the brightness of other portions. Therefore, image processing for extracting a blood vessel portion is performed by setting a luminance value serving as a determination criterion and comparing it with the luminance. The extracted blood vessel part shape information (a set of position coordinates on the blood vessel path) is stored in the blood vessel path storage area 51.

When the operator designates two points on the blood vessel path of the X-ray image 32a as reference points by operating the mouse 31, the reference point information storage unit 43 calculates and stores the coordinates of those designated positions. Then, the insertion length of the IVUS probe 21 detected by the insertion length detection unit 25 at the time of designation is read, and the coordinates of the designated position and the insertion length are associated with each other and stored in the reference point information storage area 52.
Two reference points may be stored, but if more reference points are specified, for example, the nearest two points are adopted as reference points according to the position of the blood vessel to be observed, and processing described later is performed. Will do.
When waiting for the operator to designate a position on the blood vessel, guidance display for prompting the position designation may be performed on the screen of the display device 32 to wait.

The probe position calculation unit 44 inserts the IVUS probe 21 based on the coordinates of the two designated reference points, the insertion length associated with each reference point, and the shape information of the blood vessel image between the reference points. Control is performed to calculate the position of the sensor 21a with respect to the length.
More specifically, the coordinates of the two reference points stored in the reference point storage area 52 and the shape information of the blood vessel portion between these two reference points stored in the vascular path storage area 51 (position on the vascular path) A curve distance between two reference points is calculated from a set of coordinates). On the other hand, the difference between the insertion lengths stored in the reference point storage area 52 in association with the two reference points is calculated, and the actual curve distance between the two points is calculated. Since these two curve distances are essentially the same length, the curve distance calculated from the shape information of the blood vessel portion is calibrated so as to match the actual curve distance obtained from the insertion length. Based on the result of the calibration, the curve distance between an arbitrary position on the blood vessel between the two reference points and the reference point is also calibrated. Thereby, if the distance from the reference point to any point on the blood vessel is given (corresponding to giving the insertion length), the position coordinates of that point can be uniquely determined. In this way, control for calculating the position of the sensor 21a with respect to the insertion length of the IVUS probe 21 is performed.

  Then, the position marker calculation unit 45 performs control to display a marker at the position of the sensor 21 a on the blood vessel calculated by the probe position calculation unit 44.

  Next, an image processing operation performed by the cardiovascular diagnostic imaging apparatus having the above-described configuration will be described.

(First image processing method)
FIG. 2 is a flowchart showing an example of the processing operation performed by the cardiology image diagnostic apparatus 1.
Prior to the measurement of the IVUS image, an X-ray image (hereinafter also referred to as a map image) including a contrasted blood vessel image of the region of interest A is taken in advance and stored in the X-ray image storage area 17. (S101).

Subsequently, the IVUS probe 21 is inserted into the body of the subject, and further inserted while displaying the IVUS image 32b on the display 32 (S102). At this time, the insertion length of the IVUS probe 21 is also measured.
In parallel with the display of the IVUS image 32b, the X-ray image 32a (map image 32a) of the region of interest A stored in the X-ray image storage area 17 is also displayed on the display 32 (S103).

  Subsequently, the shape of the contrasted vascular path is extracted by image processing based on pattern recognition, and the position coordinates of the vascular path are recognized (S104). Then, it waits for the operator to specify the position of the characteristic part on the blood vessel path displayed on the X-ray image 32 a by the mouse 31. FIG. 3A is a diagram showing a screen display of the display device 32 at this time. A mouse pointer C for designating a position by operating the mouse 31 is displayed on the screen along with the blood vessel path B.

When the operator continues to observe the IVUS image 32b, a feature point such as a blood vessel branch point is displayed, and the corresponding position on the blood vessel path B displayed in the X-ray image 32a (map image 32a) becomes clear. Comes. At this point, the corresponding position on the X-ray image 32a is clicked and designated as the first reference point (S105). FIG. 3B shows a screen display at this time. When the first reference point is designated, the insertion length of the IVUS probe 21 at the designated time is stored in association with the position coordinate.
When the IVUS probe 21 is further inserted, as shown in FIG. 3C, one uncharacteristic blood vessel path is displayed again in the IVUS image 32b.
As the IVUS probe 21 continues to be inserted, the blood vessel branch point that is the second feature point is displayed as shown in FIG. At this point, the corresponding position on the X-ray image 32a is clicked and designated as the second reference point (S106). FIG. 3D shows a screen display at this time.
When the second reference point is designated, the insertion length of the IVUS probe 21 at the designated time is stored in association with the position coordinate.

  Subsequently, a curve distance between the designated first reference point and the second reference point is calculated based on the shape information of the blood vessel path obtained by pattern recognition from the X-ray image. At the same time, the difference in the insertion length stored in association with each of the first reference point and the second reference point is calculated, and the actual curve distance between the two points is calculated (S107).

Subsequently, calibration is executed by obtaining a conversion formula in which the curve distance obtained from the shape information of the blood vessel path matches the curve distance obtained from the difference in insertion length (S108). With this conversion formula, calibration is performed for an arbitrary point on the blood vessel path and the first reference point (or second reference point) and distance.
As a result of the calibration, if an insertion length is given, the corresponding position on the blood vessel path (position of the sensor 21a) can be determined according to the insertion length.

Subsequently, it is determined whether another reference point is designated (S109).
When the third reference point or later (generally referred to as the Nth reference point) is designated, the process returns to S106, and the process from the designation of the reference point to the execution of calibration (S106 to S108) is repeated. In this case, the curve distance may be calculated between the Nth reference point and the (N-1) th reference point.
When completing the designation of the reference point, the process proceeds to S110.

  With the above processing, the position of the sensor 21a on the corresponding vascular path can be specified according to the insertion length of the IVUS probe 21, so that a position marker is displayed at the position of the sensor 21a on the X-ray image 32a (S110). . FIG. 4 is a diagram illustrating a screen of the display device 32 when the position marker D is displayed. Thereafter, the IVUS image 32b displayed on the screen and the position on the X-ray image 32a corresponding to the image can be simultaneously confirmed.

(Second image processing method)
FIG. 5 is a flowchart showing an example of another processing operation performed by the cardiology image diagnostic apparatus 1.
This processing method is used when an X-ray image (map image) including a contrasted blood vessel image of the region of interest A is not stored in advance.

  The region of interest A is irradiated with X-rays, an X-ray image (map image) including a contrasted blood vessel image is captured, and an X-ray image 32a (map image 32a) currently being captured is displayed on the display 32. To do. At the same time, the X-ray image (map image) is stored in the X-ray image storage area 17 (S201).

  Subsequently, the IVUS probe 21 is inserted into the body of the subject, and further inserted while displaying the IVUS image 32b on the display 32 (S202). At this time, the insertion length of the IVUS probe 21 is also measured.

  Subsequently, the shape of the contrasted vascular path is extracted by image processing based on pattern recognition, and the position coordinates of the vascular path are recognized (S203). Then, it waits for the operator to designate the position of the characteristic portion on the blood vessel path displayed on the X-ray image 32a with the mouse 31 (see FIG. 3A).

When the operator continues to observe the IVUS image 32b, a feature point such as a blood vessel branch point is displayed, and the corresponding position on the blood vessel path B displayed in the X-ray image 32a (map image 32a) becomes clear. Comes. At this point, the corresponding position on the X-ray image 32a is clicked and designated as the first reference point (S204) (see FIG. 3B). When the first reference point is designated, the insertion length of the IVUS probe 21 at the designated time is stored in association with the position coordinate.
When the IVUS probe 21 is further inserted, one uncharacteristic blood vessel path is displayed again in the IVUS image 32b (see FIG. 3C).
As the IVUS probe 21 continues to be inserted, the blood vessel branch point that is the second feature point is displayed (see FIG. 3D). At this point, the corresponding position on the X-ray image 32a is clicked and designated as the second reference point (S205) (see FIG. 3D). When the second reference point is designated, the insertion length of the IVUS probe 21 at the designated time is stored in association with the position coordinate.

  Subsequently, a curve distance between the designated first reference point and the second reference point is calculated based on the shape information of the blood vessel path obtained from the X-ray image 32a by pattern recognition. At the same time, the difference in the insertion length stored in association with each of the first reference point and the second reference point is calculated, and the actual curve distance between the two points is calculated (S206).

Subsequently, calibration is executed by obtaining a conversion formula in which the curve distance obtained from the shape information of the blood vessel path matches the curve distance obtained from the difference in insertion length (S207). With this conversion formula, the distance between an arbitrary point on the blood vessel path and the first reference point (or the second reference point) is also calibrated.
As a result of the calibration, if an insertion length is given, the corresponding position on the blood vessel path (position of the sensor 21a) can be determined according to the insertion length.

Subsequently, it is determined whether to designate another reference point (S208).
When the third reference point or later (generally referred to as the Nth reference point) is specified, the process returns to S205, and the process from the specification of the reference point to the execution of calibration (S205 to S207) is repeated. In this case, the curve distance may be calculated between the Nth reference point and the (N-1) th reference point.
When the specification of the reference point is finished, the process proceeds to S209.

  Subsequently, X-ray irradiation to the region of interest A is stopped, and the X-ray image to be displayed is switched to the X-ray image stored in the X-ray storage region 17 (S209). Thereby, the X-ray exposure to the subject after switching is eliminated.

With the above processing, the position of the sensor 21a on the corresponding X-ray image can be specified according to the insertion length of the IVUS probe 21, and thereafter, the position marker is positioned at the position of the sensor 21a on the X-ray image 32a. D is displayed (S210) (see FIG. 4).
Thereafter, the IVUS image 32b displayed on the screen and the position on the X-ray image 32a corresponding to the image can be confirmed simultaneously. In addition, since the X-ray irradiation has already been stopped, the exposure dose of the subject is reduced as compared with the conventional case.

  INDUSTRIAL APPLICABILITY The present invention can be used for a cardiovascular image diagnostic apparatus that performs X-ray image measurement and IVUS image measurement.

The block diagram which shows the structure of the image diagnostic apparatus for cardiovascular which is one Embodiment of this invention. The flowchart explaining an example of the operation | movement by the image diagnostic apparatus for cardiovascular which is one Embodiment of this invention. The figure explaining the X-ray image and IVUS image which are displayed on a display screen, and the operation state on the screen. The figure which shows the state by which the marker was displayed on the display screen. The flowchart explaining the other operation example by the image diagnostic apparatus for cardiovascular which is one Embodiment of this invention.

Explanation of symbols

10: X-ray image measurement unit 11: X-ray source 12: X-ray detector 14: X-ray image creation unit 15: X-ray image storage control unit 20: IVUS image measurement unit 21: IVUS probe 21a: sensor 24: IVUS image Creation unit 25: Insertion length detection unit 30: Image processing unit 31: Mouse 32: Display device 32a: X-ray image 32b: IVUS image 41: Image display control unit 42: Blood vessel path extraction unit 43: Reference point information storage unit 44 : Probe position calculation unit 45: Position marker display unit

Claims (4)

An IVUS image creating unit that creates an IVUS image based on an ultrasound image signal from a sensor portion of an IVUS probe inserted into a blood vessel of a region of interest;
An insertion length detector for detecting the insertion length of the IVUS probe;
An X-ray image storage area for storing an X-ray image of a region of interest including a contrasted blood vessel image;
An image display control unit that displays the X-ray image and IVUS image of the region of interest read from the X-ray image storage region side by side on the display screen;
A blood vessel path extraction unit that extracts shape information of a blood vessel image displayed on the displayed X-ray image by image processing;
A position of the feature portion on the blood vessel image of the at least two positions in the displayed X-ray image, when the position of the characterizing part of the corresponding blood vessel in IVUS images is observed is designated by the pointing device as a reference point, respectively A reference point information storage unit that stores the coordinates of each reference point and the insertion length at the time of designating each reference point in association with each other,
Based on the coordinates of each designated reference point, the insertion length associated with each reference point, and the shape information of the blood vessel image between the reference points, the position of the sensor portion with respect to the insertion length of the IVUS probe is calculated. A probe position calculation unit for
A cardiovascular image diagnostic apparatus comprising: a position marker display unit that displays a calculated position of a sensor portion on a display screen. An IVUS image creating unit that creates an IVUS image based on an ultrasound image signal from a sensor portion of an IVUS probe inserted into a blood vessel of a region of interest;
An insertion length detector for detecting the insertion length of the IVUS probe;
An X-ray image creation unit that creates an X-ray image of a region of interest including a contrasted blood vessel image at the time of IVUS image creation;
An X-ray image storage control unit for storing the generated X-ray image in an X-ray image storage area;
An image display control unit that displays the X-ray image and the IVUS image created by the X-ray image creation unit side by side on the display screen;
A blood vessel path extraction unit that extracts shape information of a blood vessel image displayed on the displayed X-ray image by image processing;
A position of the feature portion on the blood vessel image of the at least two positions in the displayed X-ray image, when the position of the characterizing part of the corresponding blood vessel in IVUS images is observed is designated by the pointing device as a reference point, respectively A reference point information storage unit that stores the coordinates of each reference point and the insertion length at the time of designating each reference point in association with each other,
Based on the coordinates of each designated reference point, the insertion length associated with each reference point, and the shape information of the blood vessel image between the reference points, the position of the sensor portion with respect to the insertion length of the IVUS probe is calculated. A probe position calculation unit for
A position marker display unit showing the calculated position of the sensor part on the display screen,
After the probe position calculation unit starts calculating the sensor position, the X-ray image generation unit stops generating the X-ray image, and the image display control unit displays the X-ray image read from the X-ray image storage area. An image diagnostic apparatus for a circulatory organ characterized by: 3. The circulatory organ according to claim 1, wherein the insertion length detection unit detects the insertion length based on an insertion speed of the IVUS probe and an insertion duration time according to the insertion speed. Diagnostic imaging device. When three or more blood vessel image positions are designated as reference points, the probe position calculation unit associates the coordinates of two reference points adjacent to each other with the sensor part of the IVUS probe and the two reference points. was inserted length, and, based on the shape information of the blood vessel image between the two reference points, that is calculated according to the position of the sensor portion in between the two reference points on the insertion length of the IVUS probe The diagnostic imaging apparatus for a circulatory organ according to any one of claims 1 and 2.

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