JP2007159934A - Comparative diagnostic reading supporting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a comparative diagnostic reading supporting apparatus which can reduce the number of diagnostic reading and improve the efficiency of the reading without generating artifacts in comparative diagnostic reading. <P>SOLUTION: The comparative diagnostic reading supporting apparatus 1 transmits the patient ID of a test subject for the reading to a PACS 2. The PACS 2 searches a current image group and a past image group of the test subject based on the patient ID. A CAD 3 implements CAD processing on the current image group and the past image group and detects abnormal sites. The comparative diagnostic reading supporting apparatus 1 separately sorts out a current or past image having the abnormal sites detected and another image which corresponds to the detected image, and displays the sorted both images comparably. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a comparative interpretation support apparatus, and more particularly, to a comparative interpretation support apparatus that can improve the efficiency of interpretation.

  Conventionally, in the comparative interpretation of CT images acquired by CT examination, the current image and the past image are compared and interpreted for all slice positions of the subject. Therefore, it is necessary for the image interpreter to interpret a slice image twice as much as a normal image. In particular, in chest CT screening, a large number of CT images used for comparative interpretation are generated.

Further, in comparative interpretation, there is a case where a difference or the like is calculated in order to emphasize the difference between the current image and the past image. Japanese Patent Application Laid-Open No. 2004-228561 discloses a technique for performing difference processing between original images to be subjected to comparative interpretation and displaying the difference images side by side.
JP 2001-184492 A

  However, when comparative interpretation is performed using difference processing, there is a problem that artifacts due to misalignment between images are likely to occur. In addition, in order to reduce artifacts, it is necessary to perform further image processing, and there is a problem that the processing becomes complicated. In addition, there is a problem that the burden of interpretation is heavy because the number of interpretation targets is large.

  The present invention has been made in view of such circumstances, and a comparative interpretation support apparatus capable of reducing the number of interpretations by an interpreter without causing artifacts in comparative interpretation and improving the efficiency of interpretation. The purpose is to provide.

  In order to achieve the above object, a comparative interpretation support apparatus according to the present invention includes a detection unit that performs computer diagnosis support processing on the current image group and the past image group under the same conditions, and detects an abnormal part. , Image selecting means for selecting the current image or the past image having the detected abnormal part from the current image group and the past image group, and the other image corresponding to the image, and the selected current image and the past Display means for displaying an image in a comparable manner.

  According to the present invention, in comparative interpretation, it is possible to reduce the number of interpretations without causing artifacts, and to improve the efficiency of interpretation.

  Hereinafter, preferred embodiments of a comparative interpretation support apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a conceptual diagram showing a schematic configuration of a comparative interpretation support system 10 to which the present invention is applied.

  A comparative interpretation support system 10 in FIG. 1 includes a comparative interpretation support apparatus 1 and a medical image management system (hereinafter referred to as “PACS”) that stores and manages medical images associated with identification information of a subject. 2) and a computer diagnosis support system (Computer Aided Detection, Computer Aided Diagnosis (hereinafter referred to as “CAD”)) 3 using medical images. These components are connected to each other by the network 4.

  In the following, the PACS 2 shows a current image group (for example, a chest CT image group generated at this year's screening) and a past image group (for example, a chest CT image group generated at last year's screening). The case of storing and managing will be described. The current image group and the past image group are a plurality of tomographic images having different slice positions.

  The comparative interpretation support apparatus 1 mainly includes a central processing unit (CPU) that controls the operation of each component, a main memory that reads a control program of the comparative interpretation support apparatus 1 and serves as a work area during program execution, and various application software Data storage device for storing images and images, a display memory for temporarily storing display data, a monitor for displaying an image based on the image from the display memory, a keyboard as an input device, a mouse, a network 4 includes a communication interface for connecting to the communication terminal 4.

  Next, the configuration of the program installed in the comparative interpretation support apparatus 1 will be described. The comparative interpretation support apparatus 1 reads the following program from the data storage device, loads it into the main memory at the time of execution, and executes it by the CPU.

  The program includes an input unit that receives input from an operator, a transmission unit that transmits subject identification information (such as a patient ID) to the PACS 2 and an image to the CAD 3, and computer diagnosis support processing (hereinafter “CAD”) from the CAD 3. A receiving unit that receives a processed image), a current image or a past image having an abnormal part detected by CAD 3 from a current image group and a past image group, which will be described later, and the other image corresponding to the image. Each of the image selection units for selecting, a display unit for displaying the selected current image and the past image in a comparable manner, a measurement unit for measuring the size of the abnormal part detected by the CAD 3, and the measured past image A warning unit that issues a warning in accordance with the rate of change of the size of the abnormal part of the current image with respect to the size of the abnormal part.

  Hereinafter, processing according to the present embodiment will be described with reference to FIGS. FIG. 2 is a sequence diagram showing a flow of processing according to the present embodiment. FIG. 3 is a schematic diagram for explaining the flow of processing.

(Step S101)
In S101, the interpreter determines a subject (patient) to be interpreted. The interpreter inputs identification information of the subject to be interpreted into the comparative interpretation support apparatus 1 through the keyboard 17 and the mouse 18. The input unit of the comparative interpretation support apparatus 1 receives input of identification information (S101). Below, the case where patient ID is used as identification information of a subject is demonstrated.

(Step S102)
In S102, the transmission unit of the comparative interpretation support apparatus 1 transmits the patient ID to the PACS 2 and makes a search request for the current image group of the subject to be interpreted (S102).

(Step S103)
In S103, the PACS 2 searches the current image group of the subject requested to be searched based on the patient ID (S103).

(Step S104)
In S104, the PACS 2 transmits the current image group of the searched subject to the comparative interpretation support apparatus 1 (S104).

(Step S105 to Step S106)
In S105 to S106, the comparative interpretation support apparatus 1 inherits the patient ID input in S101 (S105), and makes a search request to the PACS 2 for the past image group of the subject having the patient ID (S106).

(Step S107)
In S107, the PACS 2 searches for a past image group of the subject. (S107).

(Step S108)
In S108, the PACS 2 transmits the searched past image group to the comparative interpretation support apparatus 1 (S108).

(Step S109)
In S109, the transmission unit of the comparative interpretation support apparatus 1 transmits the past image group and the current image group to the CAD 3, and requests CAD processing of the current image group and the past image group (S109).

  In FIG. 3, the current image group 21 and the past image group 31 are transmitted to the CAD 3.

(Step S110)
In S110, the CAD 3 performs a CAD process on the received current image group and past image group under the same conditions (equivalent sensitivity and accuracy), and detects an abnormal part (S110). Thereby, the temporal change of the abnormal part becomes clear.

(Step S111)
In S111, the CAD 3 transmits the past image group subjected to the CAD process and the current image group to the comparative interpretation support apparatus 1 (S111).

(Step S112)
In S112, the consultation unit of the comparative interpretation support apparatus 1 receives the past image group and the current image group that have been subjected to the CAD processing.

  The image sorting unit sorts one of the current image and the past image having the abnormal part detected by the CAD 3 and the other image having the same slice position as the slice position of the one image (S112).

  In FIG. 3, an abnormal part 22 a (included in the image 22 of Slice No. 2) and an abnormal part 23 a (included in the image 23 of Slice No. 8) are detected from the images constituting the current image group 21 by CAD 3. Has been detected. Further, an abnormal region 32a (included in the image 32 of Slice No. 2) is detected from the images constituting the past image group 31. Here, Slice No indicates the slice position of the image.

  Further, the images 22 and 23 are selected from the current image group 21 by the image selection unit. In addition, images 32 and 33 are selected from the past image group 31. Here, although an abnormal part is not detected in the image 33 (Slice No. 8), since an abnormal part 23a is detected in the image 23 of Slice No. 8 in the current image group 22, it is selected by the image selection unit. Is done.

(Step S113)
In S113, the display unit of the comparative interpretation support apparatus 1 displays the selected past image and the current image so that they can be compared with each other, for example, on the display (S113).

  The radiogram interpreter compares and interprets the displayed past image and current image. Note that the interpreter may perform comparative interpretation in order to improve the accuracy of image diagnosis by interpretation, and may interpret all images constituting the current image group separately from comparative interpretation.

  The display unit may point out an abnormal part detected by the CAD process on the image (enclose the abnormal part with a line or attach an arrow).

  In FIG. 3, images corresponding to Slice No. 2 and Slice No. 8 (images 22 and 23 in the current image group, images 23 and 33 in the past image group) are compared and displayed in a comparable manner.

  Next, based on FIG. 4, the process which measures the change of the magnitude | size of the abnormal site | part detected by CAD process is demonstrated. FIG. 4 is a schematic diagram showing a method for calculating the size of the abnormal part. In FIG. 4, the image 22 of the current image group 21 and the image 32 of the past image group 31 are displayed in comparison.

  The measurement unit of the comparative interpretation support apparatus 1 measures the size of the abnormal part 22a of the image 22 and the abnormal part 32a of the image 32. The warning unit issues a warning according to a change rate of the size of the abnormal part of the current image with respect to the size of the abnormal part of the measured past image.

  In FIG. 4, the measurement unit measures the number of pixels occupied by the abnormal portions 22a and 32a, and calculates the areas of the abnormal portions 22a and 32a. Furthermore, the measurement unit calculates the ratio of the area of the abnormal part 22a in the current image to the area of the abnormal part 32a in the past image. The display unit may display the calculated area ratio on a monitor.

  In addition, when the rate of change in the size of the abnormal part exceeds a predetermined value (for example, when the abnormal part 22a is larger than the abnormal part 32a), the warning unit warns that the abnormal part has become larger. A message may be displayed on the monitor.

  The measurement unit calculates a volume of the abnormal portions 22a and 32a by forming a pseudo three-dimensional image including a plurality of images and measuring the number of voxels occupied by the abnormal portions 22a and 32a in the pseudo three-dimensional image. May be.

  Further, the warning by the warning unit is not limited to the display of the warning message, but may be issued by displaying the abnormal part in a predetermined color.

  According to the first embodiment, since an abnormal part is detected by CAD processing before comparative interpretation, interpretation by an interpreter becomes easy. Further, since the image interpreter only needs to perform comparative image interpretation on only the image in which the abnormal part is detected, the number of image interpretation can be reduced and the efficiency of image interpretation can be improved.

  In addition, since the present embodiment does not include the process of subtracting the past image from the current image, the comparative interpretation support apparatus 1 is robust with respect to the shift of the slice position between the current image group and the past image group, and is caused by the difference process. Do not generate artifacts.

  In addition, the measurement unit measures the size of the abnormal part in the current image and the past image, and a warning is issued when the size changes. Is reduced.

<Second embodiment>
In the present embodiment, CAD processing is performed in advance on the current image group and past image group for all subjects to be interpreted, and the current image group and past image group that have been subjected to CAD processing are stored in the comparative interpretation support apparatus 1. It is a form to store.

  Hereinafter, based on FIG. 5, the process of this embodiment is demonstrated. FIG. 5 is a sequence diagram showing a processing flow according to the present embodiment.

(Step S201)
In S201, all subjects (patients) to be interpreted are set, and a patient list (for example, a list showing 10 subjects who have undergone chest CT examination) is generated (step 201). The patient list stores the patient ID as the identification information of the subject.

(Steps S202 to S211)
In S202 to S211, as in S102 to S111, the current image group and the past image group of the subject to be interpreted are searched by PACS2 based on the patient ID (S202 to 208). CAD processing is performed on the current image group and the past image group searched by CAD 3 (S209 to S211).

  In steps S209 to S211, batch processing is repeatedly performed until CAD processing is performed on all subjects to be interpreted. The current image group and the past image group that have been subjected to the CAD processing are stored in the storage device of the comparative interpretation support apparatus 1.

(Step S212)
In S212, the radiogram interpreter determines a subject to be interpreted from the subjects described in the patient list (S212).

(Step S213)
In S213, the current image group and the past image group are searched from the storage device of the comparative interpretation support apparatus 1 based on the patient ID of the subject determined in S212 (S213).

(Steps S214 to S215)
In S214 to S215, as in S112 to S113, an image having an abnormal part is selected by the image selection unit (S214), and displayed for comparison at each slice position (S215).

  According to the second embodiment, a patient list to be interpreted is generated, a CAD process is performed in advance on the subject image group described in the patient list, and the CAD processed image is stored in the comparative interpretation support apparatus 1. ing. As a result, the image interpreter only needs to read out only the image in which the abnormal part is detected from the comparative image interpretation support apparatus 1 and perform the comparative image interpretation. Therefore, the number of image interpretation can be reduced, and the image interpretation burden on the image interpreter is reduced. Can be made more efficient.

<Third embodiment>
In the present embodiment, the image selection unit includes one image of the past image and the current image having the detected abnormal part, and the other image of the preceding and following slice positions including the same slice position as the slice position of the one image. It is a form which sorts. The comparative image interpretation support apparatus 1 further includes a correction unit that calculates the correlation between the current image and the past image and corrects the shift of the slice position between the current image group and the past image group according to the calculation result.

  FIG. 6 is a diagram showing a configuration of the comparative interpretation support system 10 according to the third embodiment. As in the first embodiment, the comparative interpretation support apparatus 1, PACS 2, and CAD 3 are connected to each other via the network 4.

  The program installed in the comparative interpretation support apparatus 1 further includes a correction unit that corrects a shift in slice position between the current image group and the past image group.

  Next, processing according to the present embodiment will be described with reference to FIG. FIG. 7 is a sequence diagram illustrating the flow of processing.

(Steps S301 to S312)
In S301 to S312, as in S101 to S112, the current image group and the past image group for the subject to be interpreted are searched from PACS2, and the abnormal part is detected by CAD3 (S301 to S312).

(Step S313)
In S313, the correction unit corrects the shift of the slice position between the current image group and the past image group between arbitrary images (S313).

  FIG. 8 is a diagram for explaining processing for correcting the shift of the slice position. In FIG. 8, in the current image group, an abnormal part 27a is detected in the current image 27 of Slice No. 8, and in the past image group, an abnormal part 38a is detected in the past image 38 of Slice No. 9.

  The correction unit compares the current image 27 of Slice No. 8 with the past images 35, 36, 37, 38, and 39 in the vicinity of Slice No. 8 (for example, from Slice No. 6 to Slice No. 10), and correlates the images. Ask.

  Specifically, the correction unit recognizes the shape of an abnormal part or a structure (such as a blood vessel or a bone), and calculates correlation coefficients 0 to 1 between images to be compared using a method such as pattern matching. For example, in FIG. 8, the past image 38 of Slice No. 9 has the highest correlation with the current image 27 of Slice No. 8.

  Further, the correction unit multiplies the calculated correlation coefficient by 100 to obtain the probability that the current image 27 and the past image 38 are at the same slice position (probability (%) = correlation coefficient * 100). The probability that the abnormal part 27a in FIG. 14 is the same as the abnormal part 38a in the past image 38 is calculated.

  The correction unit corrects the slice position if the calculated probability is greater than a predetermined threshold. For example, in FIG. 8, the slice positions of the past images 35, 36, 37, 38, and 39 are shifted. For example, the past image 38 is corrected from Slice No. 9 to Slice No. 8.

  The correction unit may perform interpolation when there is a difference in slice thickness between the current image group and the past image group.

  Based on the corrected slice position, the image sorting unit sorts one of the current image and the past image having the detected abnormal part and the other image at the slice position equal to the slice position of the one image. To do.

  In FIG. 8, the current image 27 and the previous and subsequent images 35, 36, 37, 38, 39 including the past image 38 at the slice position equal to the current image 27 are selected.

(Step S314)
In S314, the display unit displays the selected images so that they can be compared. (S314).

  In FIG. 8, the display unit displays a current image 27 and past images 35, 36, 37, 38, and 39. The display unit displays the probability that the abnormal part 27a and the abnormal part 38a are the same.

  According to the present embodiment, when only one of the current image group or the past image group includes an abnormal part at an arbitrary slice position, an image at the preceding and succeeding slice positions is additionally displayed. Can be prevented. In addition, the number of interpretation images can be reduced, and the interpretation efficiency can be improved.

<Fourth embodiment>
In the present embodiment, the comparative interpretation support apparatus 1 includes a CAD function.

  FIG. 9 is a diagram showing a configuration of the comparative interpretation support system 10 according to the fourth embodiment. The comparative interpretation support apparatus and the PACS 2 are connected via the network 4. The program installed in the comparative interpretation support apparatus 1 includes a CAD unit that performs CAD processing.

  Next, processing according to the present embodiment will be described with reference to FIG. FIG. 10 is a sequence diagram illustrating the flow of processing.

(Steps S401 to S408)
In S401 to S408, as in S101 to S108, the current image group and the past image group for the subject to be interpreted are retrieved from the PACS 2 and transmitted to the comparative interpretation support apparatus 1. (S401 to S408).

(Step S409)
In S409, the CAD unit of the comparative interpretation support apparatus 1 detects an abnormal part from the current image group and the past image group (S409).

(Steps S410 to S411)
In S410 to S411, as in S112 to S113, the current image or past image having an abnormal part and the other image corresponding to the image are selected and displayed (S410 to S411).

  According to the present embodiment, since an abnormal part is detected in advance by CAD processing, interpretation by an interpreter becomes easy. Further, since the image interpreter only needs to perform comparative image interpretation on only the image in which the abnormal part is detected, the number of image interpretation can be reduced and the efficiency of image interpretation can be improved.

Diagram showing the structure of a comparative interpretation support system Sequence diagram showing the flow of processing of the first embodiment Schematic diagram explaining the processing of the first embodiment Schematic diagram explaining how to calculate the size of the abnormal part Sequence diagram showing the flow of processing of the second embodiment The figure which shows the structure of 3rd embodiment. Sequence diagram showing the flow of processing of the third embodiment The figure explaining the process of correction of a slice position The figure which shows the structure of 4th embodiment. Sequence diagram showing the flow of processing of the fourth embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Comparative interpretation support apparatus, 2 ... PACS, 3 ... CAD, 4 ... Network, 10 ... Comparative interpretation support system, 21 ... Current image group, 22a ... Abnormal part, 23a ... Abnormal part, 31 ... Past image group, 32a ... Abnormal part

Claims (3)

A detection means for performing computer diagnosis support processing under the same conditions for each of the current image group and the past image group, and detecting an abnormal site;
Image selection means for selecting a current image or a past image having the detected abnormal part from the current image group and a past image group, and the other image corresponding to the image, respectively.
Display means for displaying the selected current image and the past image in a comparable manner;
A comparative interpretation support apparatus characterized by comprising:   The current image group and the past image group are a plurality of tomographic images each having a different slice position, and the image selection means includes one of the current image and the past image having the detected abnormal part, and one of the images. 2. The comparative interpretation support apparatus according to claim 1, wherein a second image having the same slice position as that of the first image is selected.   Measuring means for measuring the size of the abnormal part detected by the detecting means, and a warning for issuing a warning according to the rate of change of the size of the abnormal part of the current image with respect to the size of the abnormal part of the measured past image The comparative interpretation support apparatus according to claim 1, further comprising: means.

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