JP2015029885A - Slice image display apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slice image display apparatus which displays present and past slice images of a same patient at a slice position where a lesion part has a maximum diameter.SOLUTION: A slice image display apparatus 100 includes: a lesion detection part 110 which detects a lesion area from slice image sets imaged at different times for a same patient; a positioning image generation part 120 which performs positioning between the slice image sets; a maximum diameter slice image determination part 130 which determines a corresponding slice position by calculating the maximum diameter of a lesion; a slice image set acquisition part 140 which acquires first and second slice image sets; a slice image selection part 150 which selects the slice position having a lesion part with the maximum diameter from the slice image set; and a display control part 160 which displays the slice image of the lesion part with the maximum diameter in time-series order.

Description

  The present invention relates to a slice image display device for comparing and displaying slice images taken at different times of the same patient in image diagnosis.

  In the medical field, digitization of medical images taken of patients is being realized. Medical image data is generated by a medical image diagnostic device (modality) such as CT (Computerized Tomography) or MRI (Magnetic Resonance Imaging). At the time of diagnosis, the medical image data is displayed on a display device such as a monitor and is read by a doctor who is a user. To detect lesions, grasp pathological conditions, and observe changes over time. In particular, diagnosis using a captured tomographic image is currently used for diagnosis in many medical institutions because a three-dimensional shape and pathological condition can be grasped. In particular, as a method for supporting comparative interpretation of observing changes over time, prior document 1 describes the size of abnormal shadows appearing in each slice image after matching the slice positions of current and past slice images of the same patient. Techniques for measuring are disclosed.

  FIG. 17 is a conceptual diagram showing a comparative interpretation method. As shown in FIG. 17, since it is possible to observe the pathology of the same patient at a plurality of times at the same slice position, it is known as an effective technique for comparative interpretation.

JP 2008-259622 A

Junichi Hasegawa, Kensaku Mori, Junichiro Toriwaki, Yasushi Anno, Kazuaki Katada: “Automatic extraction of lung cancer candidate regions from continuous chest CT images using 3D digital image processing”, IEICE Transactions. V.J76-D- II, n.8, p.1587-1594, 1993 D.Rueckert, LISonoda, C.Hayes, DLGHill, MOLeach, and DJHawkes: “Nonrigid Registration Using Free-Form Deformations: Application to Breast MR Images”, IEEE TRANSACTIONS ON MEDICAL IMAGING, vol.18, no.8 , August, 1999 Masayuki Fukui, Takayuki Kitasaka, Kensaku Mori, Yasuhito Suenaga, Yoshito Mekada, Masaki Mori, Hiroki Takatsuki, Hiroshi Natori: "Study on matching lung nodules between time-lapse images in chest CT images using non-rigid registration", IEICE Technical Report, MI2005-139, 2006 Takashi Watanabe, Toshihiro Shibata: “Detection of missing ellipses using Hough transform and hierarchized image”, IEICE (D-II), vol.J73-D-II, No.2, pp.159-166, 1990

  However, in the method of Patent Document 1, since the size of the lesion is compared at the same slice position, the possibility of the lesion growing unevenly is not considered, and the current and past slice images of the same patient are not considered. The growth of the lesions that appeared was not properly grasped. FIG. 18 is a conceptual diagram showing a problem of the conventional system. FIGS. 18A and 18B show coronal images at different times, and FIGS. 18C and 18D show axial images. As shown in FIG. 18, even when the lesion is growing large, it may appear that the size of the lesion does not change when observed at the same slice position.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide a slice image display device that displays current and past slice images of the same patient at a slice position where a lesion has the maximum diameter.

  In order to achieve the above object, the present invention is configured as follows.

According to the first aspect of the present invention, a lesion detection unit that detects a lesion area from first and second slice image sets photographed at different times for the same patient, and the first and second slice image sets. An alignment image generation unit that performs the alignment of the image, a maximum diameter slice image determination unit that calculates the maximum diameter of the lesion detected by the lesion detection unit and determines a corresponding slice position, and a first and a first specified by the user A slice image set acquisition unit that acquires two slice image sets from the examination image storage unit, and the other slice having a lesion part of the maximum diameter corresponding to the lesion designated by the user in the first or second slice image set A slice image selection unit for selecting a position, a display control unit for displaying the first and second slice images in time series,
A slice image display device is provided.

  These general and specific aspects may be realized by a system, a method, a computer program, and any combination of the system, method, and computer program.

  According to the aspect of the present invention, as shown in FIG. 19, the maximum diameter position of the lesion that reflects the size of the lesion most is presented to the user instead of the same slice position. Since the current and past slice images of the same patient at the slice position where the lesion is the maximum diameter are displayed, the user can appropriately grasp the growth of the lesion that appears in the slice image.

The block diagram which shows the function structure of the slice image display which concerns on 1st Embodiment. Example of maximum diameter slice position storage format Processing flow for calculating the maximum diameter in advance Conceptual diagram showing lesion detection and labeling Conceptual image alignment between images over time Conceptual diagram of extraction between lesions Conceptual diagram of calculating the maximum lesion diameter Detailed flowchart of step S400 Example of maximum diameter slice position storage format Example of lesion label information storage format Interpretation process flow when calculating the maximum diameter in advance Conceptual diagram of target lesion designation method Example output The block diagram which shows the function structure of the slice image display apparatus which concerns on 2nd Embodiment. Processing flow for time direction display Example output Conceptual diagram showing comparative interpretation method Conceptual diagram showing the problems of the conventional system The conceptual diagram which shows the effect of the comparative interpretation system by this invention

  Embodiments of the present invention will be described below with reference to the drawings. In the following, an example will be described in which a first slice image set taken in an examination of a patient and a second slice image set taken in an examination at another time of the same patient and modality are comparatively interpreted.

(First embodiment)
FIG. 1 is a block diagram of a slice image display apparatus according to the first embodiment.

(overall structure)
The slice image display device 100 includes a lesion detection unit 110, an alignment image generation unit 120, a maximum diameter slice image determination unit 130, a slice image set acquisition unit 140, a slice image selection unit 150, and a display control unit 160. It has. The slice image display device 100 is connected to a user input unit 200, an inspection image storage unit 300, and a display unit 400.

(Each block configuration)
The inspection image storage unit 300 stores the first and second slice image sets captured by the imaging device.

  The lesion detection unit 110 detects a lesion region from the slice image set. The first and second slice image sets are acquired from the examination image storage unit 300, each lesion area is detected, a labeling process is performed, and a unique number is assigned to each lesion area. The lesion detection unit 110 outputs the detected lesion region and the labeling result to the maximum diameter slice image determination unit 130.

  The alignment image generation unit 120 performs alignment between the first and second slice image sets. The first and second slice image sets are acquired from the inspection image storage unit 300, and the slice image set of the alignment result is output to the maximum diameter slice image determination unit 130 and the inspection image storage unit 300.

  The maximum diameter slice image determination unit 130 calculates the maximum diameter of each lesion area and calculates a corresponding slice position. The alignment slice image set in the first and second slice image sets and the lesion area information with correspondence information are acquired from the alignment image generation unit 120, and the maximum diameter slice position of each lesion area is output to the examination image storage unit 300. .

  When a new lesion appears, as shown in FIG. 2, the lesion maximum diameter slice number at the time when the lesion exists may be adopted so that the same slice position can be browsed. With this output method, it is possible to grasp the growth of the lesioned part for all lesions even when the correspondence is not calculated.

  The user input unit 200 selects a case to be displayed or a lesion to be displayed.

  The slice image set acquisition unit 140 acquires an aligned slice image set to be displayed. Case information to be displayed is acquired from the user input unit 200, and the corresponding first and second aligned slice image sets are acquired from the examination image storage unit 300. The acquired slice image set is output to the slice image selection unit 150.

  The slice image selection unit 150 selects a slice image to be displayed from the acquired first and second slice image sets. The maximum-diameter slice position information of each lesion area is acquired from the examination image storage unit 300, the lesion label information to be displayed is acquired from the user input unit 200, and the first and second slice images are acquired from the slice image set acquisition unit 140. Get a set. The maximum slice position in the first or second slice image set is determined from the lesion label information input by the user input unit 200, and the slice image and time are output to the display control unit 160. When one lesion is determined, the maximum diameter slice position of the lesion corresponding to the lesion at the other time is determined by referring to the maximum diameter slice position information, and the slice image and time at that position are displayed on the display control unit 160. Output to.

  The display control unit 160 displays the first and second slice images in chronological order. The first and second slice images and time information are acquired from the slice image selection unit 150, a display position is designated based on the time information, and the first and second slice images are output to the display unit.

  The display unit 400 includes a medical high-definition monitor or the like, acquires the first and second slice images from the display control unit 160, and displays them to the user.

(Overall processing flow)
Hereinafter, the procedure of the entire process flow of the case display process performed by the slice image display device 100 will be described using the flowcharts of FIGS. 3 and 11.

  In step S100, the first and second slice image sets are acquired from the examination image storage unit 300, and a lesion area is detected from each slice image set. As a method for detecting a lesion area, for example, a technique such as Non-Patent Document 1 can be used. FIG. 4 shows a conceptual diagram of lesion detection and labeling processing results. As shown in FIG. 4, the number of lesions may differ in slice image sets with different imaging times, and the number of the labeling process result is not necessarily the same for the same lesion (for example, the label number in FIG. 4A). 2 and label number 3 in FIG. 4B are the same lesion). Therefore, correspondence extraction between lesion areas is performed in step S300.

  In step S200, alignment between the first and second slice image sets is performed. FIG. 5 shows a conceptual diagram of alignment between images over time. As shown in FIGS. 5 (a) and 5 (b), since the imaging time is different, the inspiration amount and body position of the patient are different, and the shape of the lung field and the position of the structure in the lung field are changed. As a method for aligning images having different shooting times, for example, a technique such as Non-Patent Document 2 can be used. When the above method is used, as shown in FIG. 5C, slice image sets at different shooting times have substantially the same shape.

  In step S300, as shown in FIG. 6, the correspondence in the multi-time examination of the lesion detected in step S100 is calculated. As a method for extracting correspondence between lesion areas, for example, a technique such as Non-Patent Document 3 can be used.

  In step S400, the maximum diameter of the lesion area is calculated. FIG. 7 shows a conceptual diagram for calculating the maximum lesion diameter. As shown in FIGS. 7A and 7B, the maximum diameter of the lesion area is calculated for each slice with respect to a plane parallel to the XY plane. In each slice, as shown in FIGS. 7C and 7D, an ellipse is detected from the lesion area, and the diameter of the lesion is calculated. Details of the slice selection process will be described below with reference to the flowchart shown in FIG. Here, the number of detected lesions is N.

  In step S410, the number of slices in the lesion (n) is counted. In the following, S is the number of slices in lesion (n). For example, the number of slices is 3 in FIG. 7A and the number of slices is 7 in FIG. 7B.

  In step S420, ellipse detection is performed from the intra-lesional slice image (i). As an ellipse detection method from the image, for example, a technique such as Non-Patent Document 4 can be used. For example, FIGS. 7C and 7D show the result of detecting an ellipse from a slice image.

  In step S430, the diameter of the ellipse detected from the intralesional slice (i) is calculated.

  In step S440, the largest lesion diameter calculated from each slice in a certain lesion is adopted as the lesion maximum diameter.

  The above process is repeated for each lesion, and the maximum diameter in each lesion is calculated.

  In step S500, the slice position or slice number that is the maximum lesion diameter calculated in step S400 is calculated.

  In step S600, the slice position information of the maximum diameter is stored in the inspection image storage unit 300. FIG. 9 shows an example of the maximum diameter slice position storage format. As shown in FIG. 9, the correspondence between the lesions at each imaging time and the slice position or slice number of the maximum lesion diameter are output.

  In step S700, lesion label information is stored in the examination image storage unit 300. FIG. 10 shows an example of a lesion label information storage format. FIG. 10A shows a lesion area binarized image, and FIG. 10B shows lesion label information. As shown in FIG. 10B, the background and area number information is stored in the inspection image storage unit 300 in association with the image. This area information is used when specifying the target lesion.

  In FIG. 11, in step S800, the user designates a target case. For example, case selection from a case list is applicable. Here, the slice image set of the case selected in step S800 is referred to as a first slice image set.

  In step S900, the user designates a comparative case. For example, the selection of the same patient as the case specified in step S800 and the case at a different time corresponds. Here, the slice image set of the case selected in step S900 is referred to as a second slice image set.

  In step S1000, the first and second slice image sets specified in steps S800 and S900 and the lesion label information corresponding to the first and second slice image sets are read.

  In step S1100, the lesion area noted by the user is designated. A designation operation is performed on a lesion observed by the user from the first or second slice image set. When the designation operation is performed, the lesion label information is referred to, and if it is a lesion area, the lesion label information is output to the slice image selection unit 150. FIG. 12 shows a conceptual diagram of the target lesion designation method. FIG. 12 shows an example in which a lesion area is clicked and specified using a mouse.

  In step S1200, the maximum diameter slice image is determined. First, the maximum diameter slice position information of each lesion area is acquired from the examination image storage unit 300. The lesion label information designated in step S1100 is acquired, the maximum-diameter slice position information in the first slice image set is displayed and controlled by referring to the maximum-diameter slice position information from the first and second slice image sets read in step S1000. Output to the unit 160. Next, the maximum diameter slice image of the lesion in the second slice image set corresponding to the lesion is output to the display control unit 160.

In step S1300, the maximum diameter slice image of the lesion designated by the user is displayed. FIG. 13 shows an example of the output result. In the present invention, the maximum diameter slice image in the first and second slice image sets is presented to the user, and as shown in FIG. 13, the slice position is z ₂ in FIG. As shown in FIG. 13B, an image at a slice position z ₃ different from z ₂ is presented. Further, regarding the first slice image, the slice position z ₁ at the time point designated in step S1100 is moved to the maximum diameter slice position z ₃ .

(Effect of 1st Embodiment)
According to the slice image display device of the first embodiment, slice images taken at different times of the same patient at the slice position where the lesion has the maximum diameter can be easily compared and displayed. Appropriate grasp of the growth of the lesion appearing can be obtained.

(Second Embodiment)
In the first embodiment, a slice image display device that can display slice images taken at different times of the same patient at the slice position where the lesion has the maximum diameter has been described. According to this method, it is possible to appropriately grasp the growth of the lesioned part in the examination for two hours.

  However, when browsing the growth of a lesion for a long period of time, it is necessary to compare a larger number of examination images, and the display for two hours may be insufficient. In the second embodiment, in order to solve the above problem, an image display method in a time series direction is added.

  FIG. 14 is a block diagram of a slice image display device according to the second embodiment. The description of the same components as those in the first embodiment is omitted. The overall block configuration of the second embodiment includes a time direction display control unit 170 in addition to the first embodiment. Below, the detail and operation | movement of the time direction display control part 170 in 2nd Embodiment are demonstrated.

  The time direction display control unit 170 switches the slice images before and after the change in the same window and outputs them to the display unit. For example, if the time of the second slice image is referred from the first slice image, the images are switched and displayed in the first and second order. By performing this process in an examination at two or more times, it becomes possible to view the growth of time-series lesions like an animation.

  Hereinafter, the procedure of the processing flow of slice selection processing in the second embodiment will be described with reference to the flowchart of FIG. Since steps other than step S1400 are the same as those in the first embodiment, only these two steps will be described.

  In step S1400, the maximum diameter slice images having different imaging times of the lesion designated by the user are switched and displayed. FIG. 16 shows an example of the output result. In the present embodiment, as shown in FIG. 16, images at different times are switched and displayed in an animation in the same window.

(Effect of 2nd Embodiment)
By performing the above time direction display, it becomes possible to view the growth of a time-series lesion like an animation. At this time, since the components other than the time direction display control unit 170 are the same as those in the first embodiment, the slice position where the lesion has the maximum diameter is displayed in the time direction. Therefore, it becomes possible to intuitively grasp the change in the size of the lesion in the time series direction.

  The slice image display device according to the present invention is useful at the time of interpretation work because comparative interpretation of pathological changes and size changes of lesions in examination images performed at a plurality of times becomes easy.

100 slice image display device 110 lesion detection unit 120 alignment image generation unit 130 maximum diameter slice image determination unit 140 slice image set acquisition unit 150 slice image selection unit 160 display control unit 200 input unit 300 case storage unit 400 imaging device 500 display unit

Claims (4)

A lesion detection unit for detecting a lesion region from first and second slice image sets photographed at different times for the same patient;
An alignment image generator for performing alignment between the first and second slice image sets;
A maximum diameter slice image determination unit that calculates the maximum diameter of the lesion detected by the lesion detection unit and determines a corresponding slice position;
A slice image set acquisition unit that acquires the first and second slice image sets designated by the user from the inspection image storage unit;
A slice image selection unit that selects the other slice position corresponding to the lesion designated by the user in the first or second slice image set from the slice image set acquired by the slice image set acquisition unit and having the lesion part of the maximum diameter. When,
A display control unit for displaying slice images of the first and second largest diameter lesion sites selected by the slice image selection unit in chronological order;
A slice image display device comprising: The slice image display device according to claim 1,
A slice image display device comprising a time direction display control unit that switches and displays slice images at different times in the same window. The slice image display device according to claim 1,
A maximum-size slice image determination unit that outputs the same slice position as the maximum-diameter slice position at the time when the lesion exists when the correspondence between the lesions at multiple times cannot be calculated is provided. A slice image display device characterized by the above. First and second images taken at different times with respect to the same patient, which are slice planes with the patient's body cross-section in the X and Y axis directions and the patient's body axis in the Z axis direction A slice image set acquisition unit for acquiring a slice image set;
In the first and second slice image sets, a slice image selection unit that selects the first and second slice images each having a lesion site of the maximum diameter from each slice image;
A display control unit for displaying the first and second slice images in chronological order;
A slice image display device comprising:

Images