JP2009066325A - Anterior ocular segment tomographic image analyzing system, and anterior ocular segment tomographic image photographing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anterior ocular segment tomographic image analyzing system and an anterior ocular segment tomographic image photographing apparatus by which a plurality of kinds of geometric information can easily be acquired. <P>SOLUTION: This anterior ocular segment tomographic image analyzing system includes the first step, the second step, the third step, the fourth step and the fifth step. In this case, in the first step, the setting of an analysis reference point to a characteristic area in an anterior ocular segment tomographic image, and the distance setting between an analysis reference point and an analysis reference point are performed in a random order. In the second step, a plurality of analysis referring points are set on a boundary from the analysis reference point to a tissue being located at the distance which has been set. In the third step, the distances from the analysis reference point to each of the plurality of analysis referring points, and the information of the boundary of the tissue in which the analysis referring points have been set are correlated as analysis referring point identification information. In the fourth step, a plurality of geometric information related to the tissue which is present in a vicinity of the corner is calculated based on the analysis referring point identification information and the positional relationship between the plurality of analysis referring points. In the fifth step, the calculated geometric information is displayed on a displaying means. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an anterior ocular segment image analysis system and an anterior ocular segment image capturing apparatus that can analyze an image obtained by capturing a cross section near the corner of the anterior segment, and in particular, can acquire information related to the position or shape of the iris. .

  In the field of ophthalmology, glaucoma is diagnosed using an image obtained by photographing the anterior segment of an eye to be examined. FIG. 1 shows a positional relationship among a cornea 11, a pleura 12, an iris 13, a ciliary state 14, and a crystalline lens 15, which are representative tissues existing in the anterior segment. In the diagnosis of glaucoma, the evaluation is performed by paying attention to the positional relationship of the tissue existing in the region A surrounded by the rectangle in the figure, and used for the examination of the treatment policy.

  FIG. 2 is a diagram in which the region A in FIG. 1 is extracted, and a region indicated by B between the cornea 11 and the iris 13 is a region called a corner angle. In the eyeball, metabolism called the aqueous humor circulation indicated by the dotted line f is performed, and the aqueous humor produced from the ciliary body 14 reaches the corner B via the rear surface of the iris 13 and reaches the scleral cape (in the figure). SS is discharged from an area called trabecular meshwork (TM in the figure) sandwiched between characteristic areas called SS and Schwalbe line (SL in the figure) (both are dotted in the cross-sectional image). Therefore, when the gap at the corner B is narrow, the discharge amount from the trabecular meshwork of the aqueous humor decreases, and the aqueous humor produced from the ciliary body 14 gradually accumulates in the eyeball, increasing the pressure in the eyeball. There is a causal relationship between the intraocular pressure (hereinafter referred to as intraocular pressure) and the onset of glaucoma, and glaucoma caused by a narrow corner gap is classified as closed angle glaucoma.

  The angle-closure glaucoma is classified as shown in Non-Patent Document 1 according to the mechanism of its occurrence, and is referred to in the examination of treatment methods. Non-Patent Document 2 proposes a parameter defined for performing shape evaluation in the vicinity of a corner, and also provides an anterior ocular segment imaging device having an analysis function for obtaining a partial angle or distance of the parameter. Yes.

  In recent diagnosis of closed angle glaucoma, as shown in Non-Patent Document 3, Non-Patent Document 4, or Non-Patent Document 5, it is not a simple evaluation such as the angle near the corner, It has been proposed to evaluate by combining the position or shape of the tissue existing near the corner of the iris 13 or the like.

Japan Glaucoma Society, “Glaucoma Diagnosis Guidelines (2nd edition)”, Journal of the Japan Association, 2006, 110, 10, 777-814 Charls J Pavlin et al., “UltrasoundBiomicroscopy of Anterior Segment Structures in Normal and Glaucomatous Eyes”, American Journal of Ophthalmology, 1992, 113: 381-389 Hiroyo Hirasawa et al., “Plateau Iris”, New Ophthalmology, 2006, Vol.23, No.8, 997-1001 Hiroshi Sakai et al., “Pathophysiology of angle-closure glaucoma: (1) Anatomical background of primary angle-closure”, New Ophthalmology, 2005, Vol. 22, No. 9, pp. 1169-1173 Yasuo Kurimoto, “New development of primary angle-closure glaucoma”, Clinical Ophthalmology, 2007, Vol.61, No.2, pp.128-135

  However, since many of the parameters proposed in Non-Patent Document 2 are acquired by setting new conditions after acquiring another parameter, a complicated procedure is required until the desired parameter is acquired. There are many. In addition, there are a plurality of apparatuses having an analysis function related to the parameters described above, but in order to avoid complication of internal processing due to the above-described circumstances, only the distance or angle in a specific region between the corneal posterior surface and the iris front surface is determined. It has only the function to analyze individually.

  Therefore, when performing a composite evaluation proposed in the above-mentioned Non-Patent Document 3, Non-Patent Document 4 or Non-Patent Document 5, since it cannot be performed only by information acquired using the conventional technology, It was necessary to acquire information under the conditions set by the user, and it was difficult to make a quantitative evaluation without human error.

  The present invention has been made in view of the above-mentioned circumstances, and the object of the present invention is the position or shape of the posterior surface of the cornea and the other tissues existing in the vicinity of the corners that have been implemented only individually in the conventional apparatus. For the geometric information related to, use the analysis reference point set at a predetermined distance based on the specific part of the corner area of the anterior segment and the identification information associated with each analysis reference point Accordingly, an object of the present invention is to provide an anterior ocular segment image analysis system and an anterior ocular segment image capturing apparatus that can easily acquire a plurality of types of geometric information.

  Hereinafter, embodiments of the present invention made to solve the above-described problems will be described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible.

  That is, the first aspect of the present invention includes an anterior segment cross-sectional image acquisition unit that acquires an anterior segment cross-sectional image, an input unit that inputs information necessary for performing analysis, and the acquired anterior segment Storage means for storing image information related to a cross-sectional image and input information input by the input means, display means for displaying the image information and the input information, and image analysis processing based on the image information and the input information In the anterior segment cross-sectional image analysis system having a calculation means for performing the analysis, the analysis processing is performed on a characteristic part in the anterior segment cross-sectional image, which is basic information for setting an analysis reference point referred to in the analysis. A first step of setting the analysis reference point and the distance between the analysis reference point and the analysis reference point in any order; and the analysis reference point at the boundary of the tissue located at the set distance from the analysis reference point A second step of setting a plurality, and a third step of associating each of the plurality of analysis reference points with the distance from the analysis reference point and the information on the boundary of the tissue where the analysis reference points are set as analysis reference point identification information And a fourth step of calculating a plurality of pieces of geometric information related to the tissue existing in the vicinity of a corner based on the analysis reference point identification information and the positional relationship between the plurality of analysis reference points. A fifth step of displaying the geometric information on the display means is characterized in that it comprises:

  According to the anterior segment cross-sectional image analysis system according to the present invention configured as described above, since identification information is assigned to each set analysis reference point, a geometry that can be acquired using the identification information. By performing the process of discriminating the type of geometric information, it is possible to set the analysis reference point prior to the designation of the type of geometric information to be acquired. In addition, when there are multiple types of geometric information that are determined to be obtainable in the process of determining the types of geometric information that can be obtained, the geometric information is continuously calculated. By doing so, an efficient analysis becomes possible. Furthermore, different types of geometric information are associated with each other by setting the analysis reference point so that a part of the setting position of the different analysis reference point is shared for each type of geometric information. Become.

  The second aspect of the present invention is the anterior segment cross-sectional image analysis system according to the first aspect, wherein one of the plurality of pieces of geometric information is the analysis reference point identification information. It is an angle having the analysis reference point as a vertex obtained based on the analysis reference point set at the boundary of a plurality of tissues having the same distance from the reference point.

  According to the anterior segment cross-sectional image analysis system according to the present invention configured as described above, the positional relationship between a plurality of tissues can be acquired as an angle at the same distance from the analysis reference point, and is particularly implemented in conventional analysis. It is possible to evaluate the positional relationship of the boundaries of the tissue that did not exist. Specifically, not only the angle of angles that has been conventionally acquired for evaluating the positional relationship of the front surface of the iris 13 with respect to the rear surface of the cornea 11, but also the rear surface of the iris 13 in the region near the analysis reference point or The approximate positional relationship of the ciliary body 14 can be acquired simultaneously.

  The third aspect of the present invention is the anterior segment cross-sectional image analysis system according to the first aspect, wherein one of the plurality of pieces of geometric information is the analysis reference point identification information. It is an approximate curvature of the boundary of the tissue obtained based on the analysis reference point set at a distance of at least three or more from the analysis reference point having the same boundary information.

  According to the anterior segment cross-sectional image analysis system according to the present invention configured as described above, an approximate curvature of a tissue boundary can be acquired, and a shape evaluation that has not been conventionally performed can be performed. Specifically, since the shape of the front surface or the rear surface of the iris 13 can be acquired as the curvature, it is possible to easily evaluate the iris shape that has attracted attention in recent glaucoma research.

  According to a fourth aspect of the present invention, in the anterior segment cross-sectional image analysis system according to the first aspect, one of the plurality of pieces of geometric information is the analysis reference point identification information. It is a distance between the analysis reference points for each distance from the analysis reference point obtained based on the analysis reference points set at the boundaries of a plurality of tissues existing at least three or more distances from the reference point. Features.

  According to the anterior segment cross-sectional image analysis system according to the present invention configured as described above, it is possible to acquire the inter-distance distances of a plurality of tissues according to the distance from the analysis reference point, and based on the inter-distance distance transition Evaluation is possible. Specifically, it is possible to evaluate the positional relationship between the rear surface of the cornea 11 and the front surface of the iris 13, in other words, the transition of the gap in the corner region.

  According to a fifth aspect of the present invention, there is provided an anterior segment sectional image photographing means for photographing an anterior segment sectional image, an input means for inputting information necessary for performing analysis, and the photographed anterior segment. Storage means for storing image information related to a cross-sectional image and input information input by the input means, display means for displaying the image information and the input information, and image analysis processing based on the image information and the input information In the anterior ocular segment cross-sectional image photographing apparatus having the calculating means for performing the above, the analysis processing is performed on a characteristic part in the anterior ocular segment cross-sectional image, which is basic information for setting an analysis reference point referred to in the analysis. A first step of setting the analysis reference point and the distance between the analysis reference point and the analysis reference point in any order; and setting a plurality of analysis reference points on the boundary of the tissue located at the set distance from the analysis reference point And a third step of associating each of the plurality of analysis reference points with the distance from the analysis reference point and information on the boundary of the tissue where the analysis reference point is set as analysis reference point identification information. A fourth step of calculating a plurality of geometric information relating to a tissue existing in the vicinity of a corner based on the analysis reference point identification information and a positional relationship between the plurality of analysis reference points; and the calculated geometry It is characterized by comprising the fifth step of displaying scientific information on the display means.

  According to a sixth aspect of the present invention, in the anterior segment cross-sectional image photographing device according to the fifth aspect, one of the plurality of pieces of geometric information is the analysis reference point identification information. It is an angle having the analysis reference point as a vertex obtained based on the analysis reference point set at the boundary of a plurality of tissues having the same distance from the reference point.

  According to a seventh aspect of the present invention, in the anterior segment cross-sectional image photographing device according to the fifth aspect, one of the plurality of pieces of geometric information is the analysis reference point identification information. It is an approximate curvature of the boundary of the tissue obtained based on the analysis reference point set at a distance of at least three or more from the analysis reference point having the same boundary information.

  Further, an eighth aspect of the present invention is the anterior segment cross-sectional imaging device according to the fifth aspect, wherein one of the plurality of pieces of geometric information is the analysis reference point identification information. It is a distance between the analysis reference points for each distance from the analysis reference point obtained based on the analysis reference points set at the boundaries of a plurality of tissues existing at least three or more distances from the reference point. Features.

  According to the anterior ocular segment cross-sectional image photographing apparatus according to the present invention configured as described above, an anterior ocular segment image acquisition in the anterior ocular segment image analysis system according to the first to fourth aspects of the present invention described above. Since it is directly made by the anterior segment cross-sectional image photographing means, it is possible to immediately perform analysis processing on the photographed image, and information on conditions at the time of photographing is also acquired at the same time, which affects the analysis It is possible to omit the input of correction information related to the shooting magnification and the like.

  The anterior segment cross-sectional image capturing system and the anterior segment cross-sectional image capturing apparatus according to the present invention configured as described above are configured to analyze clinical reference points set under different conditions for each type of analysis in the past. By setting based on the distance to the analysis reference point set in the characteristic part, it is possible to carry out in the same procedure and handle the analysis contents that have been evaluated individually as being associated with each other It becomes possible. In addition, by associating the analysis reference point with information about the distance from the analysis reference point and the set tissue boundary, the type of analysis that can be performed can be specified by the set analysis reference point. Even if it is added, it becomes possible to quickly acquire a new type of information that has not been set, thereby shortening the analysis time.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 3 shows a flowchart of the analysis processing of the anterior segment cross-sectional image analysis system in the present invention. Since the processing contents performed at each stage overlap with the description of the following embodiments, they are omitted here.

  FIG. 4 shows an anterior segment cross-sectional image analysis system according to the first embodiment of the present invention. The anterior segment cross-sectional image analysis system 100 displays an analysis device 101 for performing analysis, an image reading device 105 for acquiring an image, a keyboard 106a and a mouse 106b for inputting information necessary for analysis, a cross-sectional image, analysis results, and the like. And a display 107, a printer 108, and the like. The analysis apparatus 101 includes a control circuit 102 that controls the entire apparatus, an arithmetic circuit 103 that performs analysis processing, and a storage device 104 that stores analysis programs, image data, calculation results, and the like. The analysis apparatus 101 can use a commercially available personal computer. Commercially available products can be used for other components. An image photographed by the anterior segment cross-sectional image photographing device 120 is provided by an external storage medium or the like and acquired from the image reading device 102. Further, when the anterior segment cross-sectional image capturing device 120 has a communication function, it is also possible to directly read into the analysis device 101 via a communication cable (not shown) without using the image reading device 102.

Next, processing executed in the analysis apparatus 101 will be described based on the flowchart of FIG.
First, in step S1011, the analysis program is executed by operating the keyboard 106a or the mouse 106b, and image data to be analyzed is acquired. The acquired image is stored in the storage device 104.

  Next, in S1021, the stored image is displayed on the display 107. Here, when a plurality of anterior segment cross-sectional image capturing apparatuses 120 used for capturing an image are assumed, it is necessary to correct a difference in conditions such as an imaging magnification set for each apparatus. In addition, when the direction of the image is different, it is desired to change to an appropriate direction. Therefore, it is preferable to provide a step of operating the keyboard 106a or the mouse 106b to input correction information or the like when an image is displayed on the display 107. Furthermore, by making it possible to save the correction information in association with the image, it is possible to automatically display the corrected image without re-inputting the same information when the same image is used at another occasion. Become.

  Next, in step S1111, the keyboard 106a or the mouse 106b is operated to set an analysis reference point serving as a reference for analysis in the cross-sectional image displayed on the display 107. FIG. 6A shows a state in which a cursor 106c that moves in the display image in conjunction with the keyboard 106a or the mouse 106b is displayed superimposed on the image. The operator operates the keyboard 106a or the mouse 106b to move the cursor 106c to a position for setting the analysis reference point, and then sets the analysis reference point by inputting a completion signal. FIG. 6B shows a state in which an analysis standard is set for SS (scapular cape).

  Next, in S1112, the distance from the analysis reference point for setting the analysis reference point is set.

  Next, in S1121, a plurality of analysis reference points are set at the boundary of the tissue to be analyzed. FIG. 6C shows a state in which the analysis reference point CR10 is set on the rear surface of the cornea 11 selected as the boundary of the tissue to be analyzed. In S1112 as a guide for setting the analysis reference point. A circle VC10 centered on the analysis reference point SS having a radius corresponding to the set distance is displayed in the image. Further, by limiting the movement of the cursor 106c only to a range corresponding to the circumference of the circle VC10, the analysis reference point can be set at an appropriate position without displaying the circle VC10.

  Next, in S1131, the distance from the analysis reference point and the tissue boundary are acquired as information for identifying each set analysis reference point. What is necessary is just to acquire the distance set from S1112 as the distance from the analysis reference point, and the tissue boundary is specified when the tissue boundary set in S1121 is designated in advance in S1112 or the set position is confirmed in S1121. You can get it by typing.

  By repeating steps S1112 to S1131, the necessary number of analysis reference points are set.

  Next, in S1141, the analysis reference points set based on the identification information acquired in S1131 are classified, and the geometric information that can be acquired is determined. FIG. 7 is a table showing the relationship between the geometric information acquisition condition and the identification information assumed in the analysis according to the present invention. Note that the detailed contents of each piece of geometric information and the relationship between acquisition conditions will be described later in S1142, and will be omitted here. Extraction information is an item of identification information used for evaluation of acquisition conditions. For example, it is possible to determine by classifying the set analysis reference points according to the distance from the analysis reference point. In addition, when a plurality of samples are extracted, a selection unit may be provided so that unnecessary analysis processing is not performed.

Next, in S1142, geometric information related to the tissue derived from the positional relationship between the analysis reference point or the plurality of analysis reference points set in S1111 and S1121 is acquired. The geometric information acquired here is acquired in a different form by changing the setting of the analysis reference point. Some examples are shown below.
In FIG. 8A, in S1112, the distance from the analysis reference point is set to 1000 μm, and the analysis reference points CR10 and IF10 are set at the boundaries of the rear surface of the cornea 11, the front and rear surfaces of the iris 13, and the front surface of the ciliary body 14, respectively. , IR10, and CB10 are set. FIG. 8B shows the positional relationship between the set analysis reference points IF10, IR10, and CB10 and the analysis reference point CR10 as an angle with the analysis reference point SS as an apex angle. Each of the angles θ1 to θ3 schematically presents the positional relationship between the corneal posterior surface, the anteroposterior surface of the iris, and the front surface of the ciliary body at the same distance from the analysis reference point SS. Relative relationships can also be presented. The distance from the analysis reference point where the analysis reference point is set is not limited to 1000 μm. For example, even if the distance to a clinically noted part such as the Schwalbe line (SL in FIG. 2) is set. good.

  In FIG. 9A, in S1112, three distances from the analysis reference point are set in 1000 μm increments of 1000 μm, 2000 μm, and 3000 μm, and a plurality of analysis reference points IF10, IF20, and IF30 are set at the boundary of the front surface of the iris 13. This is an example of setting. FIG. 9B shows an approximate circle CIF of the analysis reference points IF10, IF20, and IF30 and shows a part thereof. The approximate circle CIF schematically presents the shape of the front surface of the iris. Note that the boundary of the tissue to be analyzed is not limited to the front surface of the iris 13, but the distance from the analysis reference point is set appropriately according to the boundary of the target tissue, An approximate circle for the front surface of the ciliary body 14 or other tissue boundary is obtained.

  FIG. 10A shows that in S1112, seven distances from 500 to 3500 μm are set in increments of 500 μm at a distance from the analysis reference point, and a plurality of analysis reference points are respectively provided at the boundary of the rear surface of the cornea 11 and the front surface of the iris 13. In this example, CR05 to CR35 and IF05 to IF35 are set. FIG. 10B shows the relative distances L05 to L35 for each analysis reference point existing at the same distance from the analysis reference point SS from the analysis reference points CR05 to CR35 and IF05 to IF35. By associating each of the relative distances L05 to L35 with the distance from the analysis reference point, the relative position change of the boundary of the different tissue where the analysis reference point is set is presented in correspondence with the distance from the analysis reference point SS. is there. FIG. 11 is a graph showing the analysis results. The boundary of the tissue to be analyzed is not limited to the rear surface of the cornea 11 and the front surface of the iris 13. Also, the distance from the analysis reference point is not limited to seven, and it is also possible to change the maximum / minimum distance and the step size as appropriate to obtain the relative distance change of the local tissue in detail. It is.

  Finally, in S1151, the result calculated in S1142 is displayed on the display 107, and output from the printer 110 as necessary.

  FIG. 12 shows a configuration of an anterior segment cross-sectional image capturing apparatus according to the second embodiment of the present invention. The anterior segment cross-sectional imaging apparatus 200 includes a control circuit 202 that controls the entire apparatus, an arithmetic circuit 203 that performs analysis, a storage device 204 that stores analysis programs, image data, analysis results, and the like, and operation and analysis of the apparatus. An input device 206 for inputting necessary information, a display device 207 and an output device 210 for displaying and outputting cross-sectional images and analysis results, and a photographing optical system 220 for photographing a cross section of the eye to be examined. The imaging optical system 220 is a well-known optical system capable of taking a cross-sectional image, which is employed in a conventionally used Shine-Pluke camera and an optical coherence tomography apparatus (OCT) that has been increasingly used in recent years. It consists of Since the above-described two cross-sectional imaging principles and the configuration of the optical system are described in many documents, a detailed description is omitted.

Next, a description will be given based on the flowchart of FIG.
First, in S2011, an anterior ocular segment image is taken. When a shooting start signal is input from the input device 206, the shooting start signal is transmitted to the control circuit 202. Upon receiving the imaging start signal, the control circuit 202 drives the imaging optical system 220 to image the anterior segment cross section. The photographed anterior segment cross-sectional image is transferred to the storage device 204 through an image sensor (not shown).

  Next, in S2021, the stored image is displayed on the display device 207. Here, the difference from the first embodiment is that the imaging optical system 220 that captures a cross-sectional image is a part of the configuration of the anterior segmental cross-sectional image capturing apparatus 200, and includes imaging information that can be acquired simultaneously with the cross-sectional image. It is possible to display an image corrected based on this, and it is not necessary to input correction information every time a new image is displayed, and it is possible to proceed to the next stage when the image is displayed.

  Next, in S2031, geometric information calculated from the displayed image is selected. The setting position of the analysis reference point necessary for calculating the selected geometric information is determined by setting the information on the tissue boundary and the distance from the analysis reference point so as to satisfy the conditions described in FIG. It is determined.

  Next, in S2032, a setting related to the tissue boundary, which is one of the information for setting the analysis reference point necessary for calculating the geometric information selected in S2031, is performed. For example, when the same analysis reference point as in FIG. 8A is set, input is performed to specify the posterior surface of the cornea 11, the front and rear surfaces of the iris 13, and the front surface of the ciliary body 14 as the boundaries of the target tissue. .

  Next, in S2111, the distance from the analysis reference point, which is one of the information for setting the analysis reference point necessary for calculating the geometric information selected in S2031, is set. As in S2032, in the case of FIG. 8A, an input for designating only one of 1000 μm is performed.

  In the above description, only the angle is selected as the geometric information. However, when a plurality of pieces of geometric information are selected, S2032 and S2111 are repeated for each type of geometric information. It is possible to set necessary information.

  Next, in step S2112, the input device 206 is operated to set an analysis reference point serving as a reference for analysis in the cross-sectional image displayed on the display device 207. Since the procedure is the same as that of the first embodiment, a description thereof will be omitted.

  Next, in S2121, analysis reference points are set. In S2031 to S2111, the tissue boundary where the analysis reference point is already set and the distance from the analysis reference point are set. In S2112, the analysis reference point is set in the image. It is possible to specify automatically by using the luminance distribution information possessed by.

  The procedure for setting the analysis reference point based on the luminance distribution information will be described with reference to FIGS. FIG. 14 shows a procedure for detecting the boundary of the rear surface of the cornea 11 located at a predetermined distance from the analysis reference point set at the pleural cape SS. Here, the predetermined distance is 1000 μm.

  First, the luminance distribution information of the neighboring area where the analysis reference point shown as “Ass” in FIG. 14A is set is acquired. FIG. 14B is an enlarged view of the region Ass. The region of Ass1 has a high luminance, and the luminance of Ass2 has a low luminance. FIG. 14C shows the brightness on the outer circumference circle of the region Ass counterclockwise with the horizontal right direction being 0 °. When the position where the luminance is Be is set as the tissue boundary, two boundaries Pαss and Pβss are specified. When the luminance distribution is acquired from the analysis reference point toward each of Pαss and Pβss, the direction toward Pαss increases. Therefore, Pαss is specified as a point on the rear surface of the cornea 11. Accordingly, it is estimated that the rear surface of the cornea 11 exists in the direction of the angle αss from the analysis reference point.

  14A is a virtual circle having a radius of 1000 μm centering on the analysis reference point, and a point on VC10 in the direction of angle αss from the analysis reference point is specified as the boundary CR10 of the rear surface of the cornea 11. A region indicated as A10 indicates a region near CR10. FIG. 14D is an enlarged view of the area A10, and FIG. 14E shows the luminance distribution on the outer circumference circle of the area A10. Similar to the region Ass, the boundaries of the tissue existing in the region A10 are detected as Pα10 and Pβ10. By evaluating whether or not CR10 exists on the line segment formed by Pα10 and Pβ10, it is possible to determine whether or not the setting position of CR10 is appropriate. FIGS. 14F and 14G show a state in which the VCR 10 deviated from an appropriate position is specified. Also in this case, the intersection between the line segment formed by Pα10 and Pβ10 and the virtual circle VC10 can be corrected as CR10.

  FIG. 15 shows a procedure for specifying the boundary of the iris 13 and other tissues with reference to the boundary CR10 of the posterior surface of the cornea 11 specified by the above procedure. FIG. 15A shows the relationship between the virtual circle VC10 and the boundaries between the respective tissues. FIG. 15B shows the luminance distribution on the VC 10 in the clockwise direction from the CR 10. The position where the luminance becomes Be is the boundary of each tissue, and the boundary of each tissue can be specified by the detection order. It should be noted here that the luminance detection direction from the above-described CR 10 needs to be appropriately selected depending on the position where the image is taken. The corner angle shown here is the left portion in FIG. However, in the case of an image related to the right part, the order of the detected tissues is reversed when the image is advanced clockwise. However, in either case, since the luminance decreases when proceeding from the CR 10 in an appropriate direction, it is possible to determine an appropriate direction based on the luminance change immediately after the start.

  By the above procedure, the boundary between the front and rear surfaces of the iris 13 and the front surface of the ciliary body 14 is specified using the rear surface of the cornea 11 as a reference, and the same analysis reference point as in FIG. 8 is set. Needless to say, the boundary of the tissue is specified in the same manner for the distance from another analysis standard by changing the virtual circle radius. In addition, it is not necessary to acquire the luminance distribution on the virtual circle over the entire circumference, and by proceeding to the next process when a predetermined number of boundaries are detected, analysis reference points can be identified efficiently. Become. Furthermore, by making it possible to select the number of tissue boundaries to be detected for each distance, it is possible to automatically set analysis reference points for acquiring a plurality of geometric information as shown in FIG. Become.

  Next, in S2131, analysis reference point identification information is acquired. However, when the analysis reference point is automatically set as in the present embodiment, it is completed when the boundary of the target tissue is detected.

  Next, in S2141 geometric information is calculated. By classifying the analysis reference point identification information acquired in S2131 based on the acquisition conditions of FIG. 7, an analysis reference point is extracted for each type of geometric information. It is also possible to select information and calculate it at the same time.

  Finally, in S2151, the result calculated in S2141 is displayed on the display 107 and output from the printer 110 as necessary.

  In the present embodiment, the photographing means for the anterior segment cross-sectional image is configured by an optical device, but is not necessarily limited thereto, and means for acquiring a cross-sectional image using ultrasonic waves. It may be configured by.

It is a figure which shows the schematic structure of an anterior eye part. It is a figure which shows the structure of the corner area | region of the anterior eye part which exists in the rectangular area A of FIG. It is a figure which shows the fundamental part of the analysis flowchart of this invention. It is a figure which shows the anterior ocular segment cross-section image analysis system which is the 1st Example of this invention. It is a figure which shows an example of the analysis flowchart of this invention. It is a figure which shows an example of the setting method of an analysis reference point and an analysis reference point. It is a table | surface which shows the relationship between the analysis reference point identification information and the acquisition conditions of geometric information. It is a figure which shows an example of an analysis process. It is a figure which shows another example of an analysis process. It is a figure which shows another example of an analysis process. FIG. 9 is a graph showing the results obtained by the analysis processing according to FIG. 8. It is a block diagram which shows the structure of the anterior ocular segment cross-section imaging device which is the 2nd Embodiment of this invention. It is a figure which shows another example of the analysis flowchart of this invention. It is a figure which shows an example of the setting of the analysis reference point using luminance distribution. It is a figure which shows another example of the setting of the analysis reference point using luminance distribution. It is a figure which shows the state which set collectively the analysis reference point referred in a some analysis process.

Explanation of symbols

SS scleral cap SL Schwalbe line TM trabecular meshwork AB corner bottom

Claims (8)

An anterior segment cross-sectional image acquisition means for acquiring the anterior segment cross-sectional image;
An input means for inputting information necessary for the analysis;
Storage means for storing image information related to the acquired anterior segment cross-sectional image and input information input by the input means;
Display means for displaying the image information and the input information;
In the anterior segment cross-sectional image analysis system having calculation means for performing image analysis processing based on the image information and the input information, the analysis processing includes:
Set the analysis reference point to the characteristic part in the cross-sectional image of the anterior segment and the distance between the analysis reference point and the analysis reference point, which are basic information for setting the analysis reference point to be referred to in the analysis. A first step;
A second step of setting a plurality of analysis reference points at a tissue boundary located at the set distance from the analysis reference point;
A third step of associating each of the plurality of analysis reference points with information about the distance from the analysis reference point and the boundary of the tissue in which the analysis reference point is set as analysis reference point identification information;
A fourth step of calculating a plurality of pieces of geometric information related to a tissue existing near a corner based on the analysis reference point identification information and a positional relationship between the plurality of analysis reference points;
A fifth step of displaying the calculated geometric information on the display means;
An anterior segment cross-sectional image analysis system characterized by comprising: One of the plurality of pieces of geometric information is obtained based on the analysis reference point set at a boundary of a plurality of tissues having the same distance from the analysis reference point that is the analysis reference point identification information. The anterior segment cross-sectional image analysis system according to claim 1, wherein the angle is an angle with the analysis reference point as a vertex. One of the plurality of pieces of geometric information is the analysis reference point set at a distance of at least three or more from the analysis reference point having the same tissue boundary information as the analysis reference point identification information. The anterior ocular segment cross-sectional image analysis system according to claim 1, wherein the curvature is an approximate curvature of the boundary of the tissue obtained based on the above. One of the plurality of pieces of geometric information is based on the analysis reference point set at the boundary of a plurality of tissues existing at a distance of at least three or more from the analysis reference point that is the analysis reference point identification information. 2. The anterior segment cross-sectional image analysis system according to claim 1, wherein the distance between the analysis reference points is a distance from the analysis reference point that is determined in this way. An anterior segment cross-sectional image photographing means for photographing the anterior segment sectional image;
An input means for inputting information necessary for the analysis;
Storage means for storing image information relating to the photographed anterior segment cross-sectional image and input information input by the input means;
Display means for displaying the image information and the input information;
In the anterior segment cross-sectional image photographing device having a calculation means for performing an image analysis process based on the image information and the input information, the analysis process includes:
Set the analysis reference point to the characteristic part in the cross-sectional image of the anterior segment and the distance between the analysis reference point and the analysis reference point, which are basic information for setting the analysis reference point to be referred to in the analysis. A first step;
A second step of setting a plurality of analysis reference points at a tissue boundary located at the set distance from the analysis reference point;
A third step of associating each of the plurality of analysis reference points with information about the distance from the analysis reference point and the boundary of the tissue in which the analysis reference point is set as analysis reference point identification information;
A fourth step of calculating a plurality of pieces of geometric information related to a tissue existing near a corner based on the analysis reference point identification information and a positional relationship between the plurality of analysis reference points;
A fifth step of displaying the calculated geometric information on the display means;
An anterior ocular segment cross-sectional image photographing device characterized by comprising: One of the plurality of pieces of geometric information is obtained based on the analysis reference point set at a boundary of a plurality of tissues having the same distance from the analysis reference point that is the analysis reference point identification information. The anterior segment cross-sectional image photographing device according to claim 5, wherein the angle is an angle having the analysis reference point as a vertex. One of the plurality of pieces of geometric information is the analysis reference point set at a distance of at least three or more from the analysis reference point having the same tissue boundary information as the analysis reference point identification information. The anterior segment cross-sectional image capturing apparatus according to claim 5, wherein the curvature is an approximate curvature of the boundary of the tissue obtained based on the curvature. One of the plurality of pieces of geometric information is based on the analysis reference point set at the boundary of a plurality of tissues existing at a distance of at least three or more from the analysis reference point that is the analysis reference point identification information. 6. The anterior segment cross-sectional image photographing device according to claim 5, wherein the distance between the analysis reference points for each distance from the analysis reference point is obtained.

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