JP6467669B2 - Determination apparatus and determination program - Google Patents

Description

  The present invention relates to a determination device and a determination program for determining malignancy or benignness of a nail plate pigment streak based on an index value calculated from a digital color image of the nail plate pigment streak.

  Malignant melanoma of the nail is generally called a nail melanoma, and develops when cancerous melanocytes are present in the nail mother. In the case of Japanese, nail melanoma accounts for about 10% of melanoma. Nail melanoma is seen as a nail plate pigment streak. Prognosis is also said to be bad, and the cause is the difficulty of definitive diagnosis.

  Melanocytes present in the nail mother are inactive under normal conditions and do not produce melanin. This melanocyte may begin to produce melanin with or without canceration. The produced melanin forms a pattern called nail plate pigment streak as the nail grows. Nail plate streaks when melanocytes are not cancerous are considered benign nevi. It is considered that it can be determined from the nail plate pigment streak pattern whether or not the melanocytes present in the nail mother are cancerous.

  However, considerable experience is required to determine whether this pattern is benign or malignant by visual observation using a dermoscope. In the case of malignant melanoma, biopsy generally does not benefit the patient. These make definitive diagnosis difficult. It is also a factor that worsens the prognosis. Therefore, the realization of a non-invasive and objective nail plate pigment streak determination method is strongly demanded from the clinical field. There is also a strong demand for a visualization method that can visually represent the difference between benign and malignant.

  Therefore, the present inventors have invented a method for non-invasively and objectively determining the benign or malignant nature of the nail plate pigment streak (see, for example, Patent Document 1 and Patent Document 2). Such a determination device regards the RGB parameter value of each pixel in the digital color image of the nail plate pigment streak as a three-dimensional vector having these three components as a latitude variable in the RGB space of the three-dimensional vector. A longitude variable is obtained, and an index value is obtained from a distribution of points defined based on the obtained latitude variable and longitude variable. The determination device further determines the malignancy and benignity of the nail plate pigment streak by distinguishing the index value by a threshold value.

JP 2010-252895 A JP 2011-130897 A

  Patent Documents 1 and 2 propose to determine benign or malignant nail plate pigment streak in one inspection. However, although it was determined to be malignant in the first test, it was diagnosed as benign by the subsequent biopsy, or conversely, it was determined to be benign in the first test but was diagnosed as malignant by the subsequent course. In some cases, it is necessary to improve the determination accuracy.

  The benign or malignant diagnosis of the nail plate pigment streak is made by biopsy. However, in the biopsy, the nail mother's cells are obtained after removing the subject's nails, so the burden on the subject is great. Therefore, as disclosed in Patent Document 1 and Patent Document 2, there is a great expectation for a non-invasive and objective determination method. In addition, since the determination methods disclosed in Patent Document 1 and Patent Document 2 are non-invasive and objective, it is possible to continuously perform an inspection, not to miss malignancy, and to respond early. Be expected.

  Therefore, development of a determination apparatus and a determination program capable of determining benign or malignant nail plate pigment streak with high accuracy is expected.

  Accordingly, an object of the present invention is to provide a determination device and a determination program capable of determining benign or malignant nail plate pigment streak with high accuracy.

  The first feature of the present invention is that the RGB parameter value of each pixel in the digital color image of the nail plate pigment line is regarded as a three-dimensional vector having these three components, and the latitude in the RGB space of the three-dimensional vector. The present invention relates to a determination apparatus that calculates an index value from a distribution of points defined based on a variable and a longitude variable, and determines malignancy or benignity of the nail plate pigment streak based on the index value. The determination device according to the first aspect of the present invention is an index value registration that stores an index value calculated from a digital color image of a nail plate pigment streak in association with a shooting time of the digital color image and stores the index value in the index value data. A means for reading out the index value data, and determining whether the index value is increasing or not with a lapse of time. Result output means for outputting the result to the output device is provided.

  The determination means obtains the latest index value and the previous index value from the index value data, and when the latest index value and the previous index value are higher than the threshold, or when the latest index value is higher than the previous index value, the nail plate It may be determined that the pigment streak is likely to be malignant. The determining means obtains the latest index value and the previous index value from the index value data, and when the latest index value and the previous index value are lower than the threshold and the latest index value is lower than the previous index value, the nail plate pigment It may be determined that the possibility that the filament is benign is high.

  The determination means obtains a plurality of index values registered in the index value data, calculates a slope of transition of the plurality of index values over time, and when all of the plurality of index values are higher than a threshold value, Alternatively, when the inclination tends to increase, it may be determined that the nail plate pigment streak is likely to be malignant. The determination unit obtains a plurality of index values registered in the index value data, calculates a slope of the transition of the plurality of index values over time, all of the plurality of index values are lower than a threshold, and the slope May be determined that the nail plate pigment streak is likely to be benign.

  Here, the determination means may determine malignancy or benign with respect to the nail plate pigment striatum other than the non-pigmented nail plate melanoma.

  When the digital color image relates to a child's nail plate pigment streak, the result output means may display the transition of the index value calculated from the digital color image.

  The second feature of the present invention is that the RGB parameter values of each pixel in the digital color image of the nail plate pigment line are regarded as a three-dimensional vector having these three components, and the latitude in the RGB space of the three-dimensional vector. The present invention relates to a determination program that calculates an index value from a distribution of points defined based on a variable and a longitude variable, and determines malignancy or benignity of the nail plate pigment streak based on the index value. The determination program according to the second feature of the present invention stores the index value calculated from the digital color image of the nail plate pigment streak in the index value data in association with the photographing time of the digital color image. Index value registration means, determination means for reading index value data, and determining whether malignant or benign nail plate streak is malignant or not based on whether or not the index value is increasing with time The determination result by the means is caused to function as a result output means for outputting to the output device.

  The determination means obtains the latest index value and the previous index value from the index value data, and when the latest index value and the previous index value are higher than the threshold, or when the latest index value is higher than the previous index value, the nail plate It may be determined that the pigment streak is likely to be malignant. The determining means obtains the latest index value and the previous index value from the index value data, and when the latest index value and the previous index value are lower than the threshold and the latest index value is lower than the previous index value, the nail plate pigment It may be determined that the possibility that the filament is benign is high.

  The determination means obtains a plurality of index values registered in the index value data, calculates a slope of transition of the plurality of index values over time, and when all of the plurality of index values are higher than a threshold value, Alternatively, when the inclination tends to increase, it may be determined that the nail plate pigment streak is likely to be malignant. The determination unit obtains a plurality of index values registered in the index value data, calculates a slope of the transition of the plurality of index values over time, all of the plurality of index values are lower than a threshold, and the slope May be determined that the nail plate pigment streak is likely to be benign.

  Here, the determination means may determine malignancy or benign with respect to the nail plate pigment striatum other than the non-pigmented nail plate melanoma.

  When the digital color image relates to a child's nail plate pigment streak, the result output means may display the transition of the index value calculated from the digital color image.

  ADVANTAGE OF THE INVENTION According to this invention, the determination apparatus and determination program which can determine the benign or malignant of a nail plate pigment striation can be provided with high precision.

It is a figure explaining the hardware constitutions and functional block of the determination apparatus which concerns on embodiment of this invention. In embodiment of this invention, it is a figure explaining a mode that a nail plate pigment filament is image | photographed using a dermoscope. In an embodiment of the present invention, it is a figure explaining coordinates showing a definition of a longitude variable and a latitude variable in RGB three-dimensional space used when calculating an index value. It is a figure explaining an example of the distribution map of the longitude variable and the latitude variable in a malignant example and a benign example of a nail plate pigment striation. It is a flowchart explaining the determination process in embodiment of this invention. It is a figure explaining an example of the result display screen which the determination apparatus which concerns on embodiment of this invention outputs. It is a figure explaining an example of transition of the index value computed in an embodiment of the invention. In the 1st modification of this invention, it is a figure explaining the increase, fixed, and reduction | decrease of an index value. It is a figure explaining each case of the judgment processing in the 2nd modification of the present invention. It is a flowchart explaining the determination process in the 2nd modification of this invention.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

(Overview)
A determination apparatus 1 according to an embodiment of the present invention will be described with reference to FIG. As shown in FIG. 2, the determination device 1 according to the embodiment of the present invention obtains an index value based on image data obtained by photographing the nail plate pigment filament 102 generated on the subject's nail 101 with the digital color dermoscope 2. calculate. The determination apparatus 1 determines the malignancy or benignity of the nail plate pigment streak 102 based on a change in the index value over time. This determination result supports the diagnosis of the nail plate pigment streak by a user such as a doctor.

  Here, the process in which the determination apparatus 1 calculates the “index value” according to the embodiment of the present invention will be described.

  The index value according to the embodiment of the present invention is calculated based on the idea that “color mottleness” of the nail plate pigment streak is an important criterion for identifying benign or malignant.

  The determination apparatus 1 extracts only the nail plate portion from the full-scale image of the color image acquired from the digital color dermoscope 2 as the analysis target region. The determination device 1 excludes from the extracted analysis target region the portion where the jelly bubbles and irregular reflection used at the time of photographing are significant.

  In order to make effective use of the three degrees of freedom of a color image, a three-dimensional vector having RGB parameters as components in an RGB three-dimensional space is considered. That is, consider a three-dimensional vector pi = (Ri, Gi, Bi) whose components are RGB parameter values possessed by each pixel (i-th pixel) in the analysis target region.

  Next, as shown in FIG. 3, a latitude variable and a longitude variable in an RGB three-dimensional space are obtained. The RG plane is regarded as the equator plane, the angle formed by the vector with the RG plane is introduced as the latitude variable θ, and the angle formed by the projection of the vector onto the RG plane from the R axis is introduced as the longitude variable Φ.

  The longitude variable (Φi) and the latitude variable (θi) are calculated by the following equation (1).

  The unit of the calculated angle may be an arc method (rad) or a frequency method (°). The following shows the results measured by the arc method (rad).

  As shown in FIG. 4, for each image, the obtained (Φi, θi) is plotted in two-dimensional orthogonal coordinates with the horizontal axis Φi and the vertical axis θi. FIG. 4 shows the malignancy of the nail melanoma.

  As the distribution of points, use the distance from the point (1, 0, 0) on the unit sphere surface calculated from (θ, Φ) instead of the method of expressing on the (θ, Φ) plane. Is also possible.

  The variance of the plotted points is calculated by the following formula 2 to define the index value DI.

  Note that the average distance from the center of gravity of the distribution of each point can also be used as the index value DI.

  Based on the index value, a threshold is set to distinguish the benign group from the malignant group. This threshold value is statistically calculated by ROC (Receiver Operating Characteristics) analysis, analysis that minimizes the average of false positives and false negatives, and the like. In the embodiment of the present invention, the threshold is 0.0928, and when the index value calculated from the color image of the subject's nail is higher than the threshold, it is determined as malignant, and when it is lower than the threshold, benign judge.

  A distribution map of longitude and latitude (Φi, θi) will be described with reference to FIG. In FIG. 4, the vertical axis is the latitude variable θ, and the horizontal axis is the longitude variable Φ. A unit system (rad) of arc degree method is used. FIG. 4 (a) corresponds to the initial melanoma, and FIG. 4 (b) corresponds to the benign nevi.

  The index value DI of the initial melanoma shown in FIG. 4 (a) was 0.1772, and the index value DI of benign nevi shown in FIG. 4 (b) was 0.0417. As indicated by the numerical values, in the case of benign nevi, (Φi, θi) tends to concentrate in a narrow range, whereas in the case of initial melanoma, the distribution tends to be scattered. Similar trends were seen in the melanoma and nevus groups examined.

This indicates that “color diversity” exists in melanoma. Therefore, subjectively, it is possible to understand that the distribution is (Φi, θi) shown in FIG. It is considered that the objectivity of the expression is further improved by the index value DI. This is because the p-values of DI values in the melanoma group and the nevus group are p <1.0 × 10 ⁻⁵ . Here, the p-value represents the probability that a difference in DI value between the melanoma group and the nevus group occurs by chance, and if it is small, it means that there is a significant difference in the DI value between the two.

  In addition, since the index value according to the embodiment of the present invention is based on the analysis of the pigment, it is not suitable for detecting the pigmentless nail plate melanoma.

(Judgment device)
The determination device 1 is a general computer including a storage device 10, a processing device 20, and an input / output interface 30. The determination device 1 is connected to the digital color dermoscope 2, the input device 3, and the output device 4 via the input / output interface 30.

  In the embodiment of the present invention, the case where the digital color dermoscope 2, the input device 3, and the output device 4 are configured by a separate housing from the determination device 1 will be described, but may be incorporated in the determination device 1.

  As shown in FIG. 2, the digital color dermoscope 2 includes a digital color dermoscope main body 201 and a CCD camera (two-dimensional solid-state imaging device) 202. The digital color dermoscope 2 acquires color image data (for example, jpg format) of the nail plate pigment filament 102 and inputs it to the input / output interface 30 of the determination apparatus 1. In the embodiment of the present invention, a case where a digital color dermoscope image captured by the digital color dermoscope 2 is used will be described. However, the present invention is not limited to this image as long as the index value of the nail plate pigment streak can be calculated.

  The input device 3 is a keyboard, a mouse, or the like. The input device 3 acquires a user instruction by a user operation and inputs it to the input / output interface 30 of the determination device 1. The user's instruction includes subject information such as a subject identifier, an instruction to acquire color image data from the digital color dermoscope 2, and an instruction related to determination of the nail plate pigment streak 102.

  The output device 4 is a display or the like. The output device 4 displays the data acquired from the input / output interface 30 of the determination device 1 in a format that can be recognized by the user. The data acquired from the input / output interface 30 is, for example, a screen for inputting a user instruction, a determination result of the nail plate pigment line 102, a transition graph of index values, and the like.

  The storage device 10 is a hard disk, ROM, RAM, CD-ROM, USB memory, or the like, and is a storage medium that stores data referred to by the processing device 20 and processing results of the processing device 20. The storage device 10 stores a determination program according to the embodiment of the present invention and also stores index value data 11.

  The index value data 11 is data in which the index value calculated from the digital color image of the nail plate pigment filament 102 is associated with the shooting time of the digital color image. When storing data of a plurality of subjects, the index value data 11 stores the identifier of the affected part, the photographing time of the digital color image, and the index value calculated from the digital color image in association with the identifier of the subject. May be. Here, the identifier of the affected area is specified by any one of the right hand / left hand / right foot / left foot and the thumb / index finger / middle finger / ring finger / little finger, for example.

  The processing device 20 reads and processes the data stored in the storage device 10 and stores the processing result in the storage device 10. The processing device 20 functions as each unit illustrated in FIG. 1 by reading and executing the determination program stored in the storage device 10. The processing device 20 includes index value registration means 21, determination means 22, and result output means 23.

  The index value registration means 21 stores the index value calculated from the digital color image of the nail plate pigment filament 102 in the index value data 11 in association with the photographing time of the digital color image. The index value registration unit 21 calculates an index value from the digital color image by the above-described calculation method, and stores it in the index value data 11.

  Specifically, the index value registration means 21 regards the RGB parameter values of each pixel in the digital color image of the subject's nail plate pigment streak 102 as a three-dimensional vector having these three components, and An index value is calculated from the distribution of points defined based on latitude and longitude variables in the RGB space of the vector. Here, the calculation method of the index value is disclosed in Japanese Unexamined Patent Application Publication No. 2010-252895 or Japanese Unexamined Patent Application Publication No. 2011-130897.

  When the index value is calculated, the index value registration unit 21 stores the calculated index value in the index value data 11 in association with the subject identifier and the imaging time of the nail plate pigment line 102.

  The determination means 22 reads the index value data 11 and determines whether the nail plate pigment streak 102 is malignant or benign. The determination means 22 determines the malignancy or benignity of the nail plate pigment streak based on whether or not the index value tends to increase with time. Here, the determination unit 22 may further determine whether the index value is higher than the threshold value, and determine whether the nail plate pigment streak is malignant or benign. The determination unit 22 determines that the index value is always malignant when the index value exceeds the threshold value or when the index value tends to increase. The determination unit 22 determines that the index value is benign when the index value is always below the threshold value and the index value is decreasing. In other cases, the determination means 22 determines that follow-up observation is necessary in the future.

  In the embodiment of the present invention, the determination unit 22 acquires the latest index value and the previous index value from the index value data 11 and determines based on these two values. The determination unit 22 determines that the nail plate pigment streak is likely to be malignant when both the latest index value and the previous index value are higher than the threshold value, or when the latest index value is higher than the previous index value. When both the latest index value and the previous index value are lower than the threshold value and the latest index value is lower than the previous index value, the determination unit 22 determines that the nail plate pigment streak is likely to be benign. In other cases, the determination unit 22 determines that the follow-up observation is necessary.

  With reference to FIG. 5, the determination process by the determination means 22 which concerns on embodiment of this invention is demonstrated. The process shown in FIG. 5 shows a process for determining a specific affected part of a specific subject, such as the middle finger of the subject A's right hand.

  First, in step S1, the determination unit 22 acquires the latest index value and the previous index value. If the determination unit 22 determines in step S2 that both the latest index value and the previous index value are greater than or equal to the threshold value, the process proceeds to step S5.

  In step S2, when the determination unit 22 determines that at least one of the latest index value and the previous index value is not greater than or equal to the threshold value, that is, at least one of the latest index value and the previous index value is less than the threshold value, the determination unit 22 proceeds to step S3. In step S3, the determination means 22 proceeds to step S5 when determining that the latest index value is larger than the previous index value, and proceeds to step S4 when determined to be smaller.

  If the determination unit 22 determines in step S4 that both the latest index value and the previous index value are less than the threshold value, the process proceeds to step S7. In step S4, if at least one of the latest index value and the previous index value is not less than the threshold value, that is, if the latest index value or the previous index value is determined to be greater than or equal to the threshold value, the determination unit 22 proceeds to step S6.

  In step S5, the determination unit 22 determines that the possibility of malignancy is high, outputs “risk level [high]”, and outputs a message indicating that a biopsy is suggested. That is, the determination unit 22 determines that there is a high possibility of malignancy when both the latest index value and the previous index value are greater than or equal to the threshold value, or when the latest index value is greater than the previous index value.

  In step S <b> 6, the determination unit 22 determines that further follow-up observation is necessary, outputs “risk degree [medium]”, and outputs information indicating that the follow-up observation is required. That is, the determination means 22 determines that further follow-up observation is necessary if it cannot be determined as malignant or benign in step S5 and step S7.

  In step S <b> 7, the determination unit 22 determines that the possibility of benign is high, and outputs “risk degree [small]”. That is, the determination unit 22 determines that the possibility of being benign is high when both the latest index value and the previous index value are less than the threshold and the latest index value is smaller than the previous index value.

  Here, the determination method shown in FIG. 5 is suitable for determining adult nail plate streaks other than non-pigmented nail plate melanoma. The nail plate pigment striatum and the non-pigmented nail plate melanoma in children need not be determined by the determination method shown in FIG. Therefore, it is preferable that the determination apparatus 1 displays in advance a warning to the effect that the determination method according to the embodiment of the present invention is not applied to a child's nail plate pigment striatum or non-pigmented nail plate melanoma.

  The result output unit 23 outputs the determination result by the determination unit 22 to the output device 4. The result output unit 23 displays, for example, the screen shown in FIG.

  FIG. 6 shows a result display screen V of a subject. The result display screen V includes a display setting unit P, an index value list display unit L, and an index value graph display unit G. The index value list display unit L and the index value graph display unit G display in a list format and a graph format, respectively, based on index values that match the information set in the display setting unit P.

  The index value graph display unit G includes a result display unit R. The result display unit R displays the determination result by the determination unit 22. In the graph shown in FIG. 6, the latest two index values are both lower than the threshold value but tend to increase. Therefore, “risk level [high]” is output, suggesting malignancy of the nail plate pigment streak. Outputs the effect.

  The result display section R displays red when “risk level [high]”, displays yellow when “risk level [medium]”, and displays blue when “risk level [low]”. For example, a display may be made so that a doctor or the like can easily recognize the color.

  The display setting unit P includes a subject selection unit P1, a display affected part selection unit P2, a data option selection unit P3, an elapsed time (month) option selection unit P4, an index value option selection unit P5, and a redisplay button B1.

  The subject selection unit P <b> 1 is an interface that selects a subject identifier stored in the index value data 11. 6 illustrates a case where only one subject is selected, a plurality of subjects may be selected, and control may be performed so that index value data of a plurality of subjects are displayed simultaneously.

  The display affected part selection part P2 is an interface for selecting an affected part. In the figure shown in FIG. 6, a case where only one affected part is set will be described. However, a plurality of affected parts may be selected, and control may be performed so that index value data of a plurality of affected parts are displayed simultaneously.

  The data option selection unit P3, the elapsed time (month) option selection unit P4, and the index value option selection unit P5 are interfaces for selecting a display area of the index value graph display unit G.

  When one of the subject selection unit P1, the display affected part selection unit P2, the data option selection unit P3, the elapsed time (month) option selection unit P4, and the index value option selection unit P5 is changed, the redisplay button B1 is changed. It is a button for inputting an instruction to redisplay the index value graph display unit G based on the changed setting.

  Here, the result output means 23 displays the risk level for the adult nail plate pigment streak as shown in FIG. 6, but does not need to display the risk level for the child nail plate pigment streak. . That is, when the digital color image photographed with the digital color dermoscope 2 relates to a child's nail plate pigment streak, the result output means 23 displays the transition of the index value calculated from the digital color image.

  In the embodiment of the present invention, the index value is calculated based on the idea that “color mottleness” of the nail plate pigment streak is an important criterion for identifying benign or malignant, and time The color changes with the passage of time. As a result, even if the index value is lower than the threshold value, if the index value tends to increase, the possibility of malignancy (excluding non-pigmented melanoma) is considered high. This is thought to be due to, for example, the increase in the activity of the melanin product mottled by melanocytes in the nail tissue over time.

  On the other hand, when the index value is decreasing, it means that the “color mottleness” is reduced, that is, the color is homogenized, and it is caused by the increase in eumelanin products in the nevi matrix. Conceivable. As a result, if the current index value is lower than the threshold and the index value tends to decrease, the possibility of benign is considered high.

  With reference to FIG. 7, the effect of the determination apparatus 1 which concerns on embodiment of this invention is demonstrated. The example shown in FIG. 7 shows the transition of the index values of 6 cases diagnosed as benign and 3 cases diagnosed as malignant.

  One malignant A of three malignant cases is a case in which malignancy is determined by biopsy, and the latest index value and the previous index value are both lower than the threshold value, but the latest index value is larger than the previous index value. According to the conventional determination method, there is a problem that such cases are determined to be benign if the latest index value is less than the threshold value. On the other hand, according to the embodiment of the present invention, the latest index value is larger than the previous index value and tends to increase, so that “risk level [high]” and “malignant” are output so that malignancy is early. It is possible to judge and suggest a biopsy.

  One benign B of the six benign cases exceeds the threshold value in the previous index value, but the latest index value is lower than the threshold value and shows a decreasing tendency. According to the conventional determination method, it may be determined that such a case is malignant because the previous index value is larger than a threshold value. On the other hand, the embodiment of the present invention outputs “risk [medium]” and “follow-up observation” to avoid immediate biopsy and may change between benign or malignant in the future. Suggest.

  One benign E of the six benign cases is that the previous index value and the latest index value are both less than the threshold value, and the latest index value is lower than the previous index value, so that the determination apparatus 1 according to the embodiment of the present invention According to this, it can be judged as benign. Thereby, the determination apparatus 1 can determine the benign or malignant state of the nail plate pigment streak without performing a biopsy.

  Thus, the determination apparatus 1 according to the embodiment of the present invention determines benign and malignant nail plate pigment streaks in consideration of the time transition of the index value.

  Thus, the determination apparatus 1 according to the embodiment of the present invention can improve the accuracy of diagnosis. Furthermore, the determination apparatus 1 can be expected to reduce the burden on the subject due to biopsy by improving the accuracy of the noninvasive test and not to miss a malignant case.

(First modification)
In the embodiment of the present invention, the determination unit 22 has been described based on whether or not the latest index value is larger than the previous index value. However, in the first modification, the latest index value and Add the “fixed” judgment that the index value is almost the same as the previous time.

  In the first modified example, as shown in FIG. 8, the determination unit 22 considers “fixed” not only when the latest index value is the same as the previous index value but also when the difference is within 2α. In this case, in step S3 of FIG. 5, the determination unit 22 determines that the latest index value is malignant when the latest index value is larger than the previous index value by a predetermined value (α) or more. On the other hand, when the latest index value is smaller than the previous index value, or when the difference is less than the predetermined value (α), the process proceeds to step S6 and it is determined that follow-up observation is necessary.

  For example, in the case of benign D shown in FIG. 7, both the latest index value and the previous index value are less than the threshold value, and the latest index value is larger than the previous index value, but is almost constant. In the embodiment of the present invention, malignancy is suggested by the fact that the latest index value is larger than the previous index value, but in the first modified example, it can be determined as benign by determining that it is substantially constant. .

  As described above, the determination means 22 avoids an immediate biopsy by considering a buffer of a predetermined value in the determination of the size of the latest index value and the previous index value. It is possible to make an appropriate determination according to the change in.

(Second modification)
In the embodiment of the present invention, the case where the determination unit 22 determines based on the binary value of the latest index value and the previous index value has been described. However, in the second modification, the determination unit 22 is based on a plurality of values. A case of determination will be described.

  The determination unit 22 according to the modification obtains a plurality of index values registered in the index value data 11, and calculates the inclination of the transition of the plurality of index values over time. The determination unit 22 determines that the nail plate pigment streak is highly likely to be malignant when all of the plurality of index values are higher than the threshold value or when the inclination tends to increase. When all of the plurality of index values are lower than the threshold value and the inclination tends to decrease, the determination unit 22 determines that the nail plate pigment streak is highly likely to be benign. In other cases, the determination unit 22 determines that the follow-up observation is necessary.

  With reference to FIG. 9, the case where the determination means 22 which concerns on a 2nd modification determines based on all the some parameter | index values is demonstrated. In FIG. 9, the solid line in the horizontal direction indicates the threshold value. Further, the solid line toward the upper right indicates an increasing tendency of the inclination, the one-dot chain line toward the horizontal direction indicates a constant inclination, and the two-dot chain line toward the lower right indicates a decreasing tendency of the inclination.

  FIG. 9A shows a case where all index values are higher than the threshold value. In this case, the determination unit 22 determines that the possibility of malignancy is high regardless of the inclination, and outputs “risk level [high]”.

  FIG. 9B shows a case where all index values are lower than the threshold value. In this case, the determination unit 22 outputs “risk degree [high]” when the inclination is increasing, and outputs “risk degree [medium]” when the inclination is constant, and when the inclination is decreasing, Outputs "Danger Level [Small]".

  FIG. 9C illustrates a case where some index values are higher than the threshold value and some index values are lower than the threshold value. In this case, the determination means 22 outputs “risk level [high]” when the inclination is increasing, and determines that further follow-up observation is necessary when the inclination is constant or decreasing, and “risk level [medium]”. Is output.

  The determination means 22 according to the second modification is determined by the process shown in FIG. The process shown in FIG. 10 shows a process for determining a specific affected part of a specific subject such as the middle finger of the subject A's right hand.

  First, in step S11, the determination unit 22 extracts an index value of a specific affected part of a specific subject from the index value data 11, and calculates a slope from the extracted index value. The inclination is calculated by the inclination of a straight line that approximates each index value by, for example, the least square method.

  If it is determined in step S12 that all past index values from the first index value to the latest index value exceed the threshold, the process proceeds to step S15.

  If the determination unit 22 determines in step S12 that some of the index values from the first index value to the latest index value do not exceed the threshold value, the process proceeds to step S13. In step S13, the determination means 22 proceeds to step S15 when the inclination calculated in step S11 is increasing, proceeds to step S16 if constant, and proceeds to step S14 if it is decreasing.

  If the determination unit 22 determines in step S14 that all past index values from the first index value to the latest index value do not exceed the threshold value, the process proceeds to step S17. If the determination unit 22 determines in step S14 that the partial index values from the first index value to the latest index value exceed the threshold value, the process proceeds to step S16.

  In step S15, the determination means 22 determines that the possibility of malignancy is high, outputs “risk level [high]”, and outputs a message indicating a biopsy. That is, the determination means 22 determines that there is a high possibility of being malignant when all the index values are equal to or greater than the threshold value or when the inclination is increasing.

  In step S <b> 16, the determination unit 22 determines that further follow-up observation is necessary, outputs “risk degree [medium]”, and outputs information indicating that the follow-up observation is required. That is, the determination means 22 determines that further follow-up observation is necessary when it cannot be determined that it is malignant or benign in step S15 and step S17.

  In step S <b> 17, the determination unit 22 determines that the possibility of benign is high, and outputs “risk level [small]”. That is, the determination means 22 determines that there is a high possibility of benign if all the index values are less than the threshold value and the inclination tends to decrease.

  As shown in the second modification, the determination unit 22 may determine malignancy or benignity of the nail plate pigment streak based on a plurality of values. In addition, with reference to FIG. 9 and FIG. 10, the case where the determination is made with reference to the index values of the entire period of the index value data 11 has been described. Variations such as excluding index values outside a predetermined range such as when the value is large or small are also conceivable.

(Other embodiments)
As described above, the embodiments of the present invention and the first and second modifications have been described. However, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. . From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.

  For example, the determination apparatus described in the embodiment of the present invention may be configured on a single piece of hardware as shown in FIG. 1 or may be configured on a plurality of pieces of hardware according to the functions and the number of processes. May be. The determination apparatus may be mounted on a server connected via a communication network, and may be configured to acquire and determine a color image from the digital color dermoscope 2 via the communication network.

  It goes without saying that the present invention includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

DESCRIPTION OF SYMBOLS 1 Determination apparatus 2 Digital color dermoscope 3 Input apparatus 4 Output apparatus 10 Storage apparatus 11 Index value data 20 Processing apparatus 21 Index value registration means 22 Judgment means 23 Result output means 30 Input / output interface 101 Nail 102 Nail plate pigment line 201 Digital color Dermoscope body 202 CCD camera

Claims (14)

The RGB parameter values of each pixel in the digital color image of the nail plate pigment line are regarded as a three-dimensional vector having these three components, and are defined based on latitude and longitude variables in the RGB space of the three-dimensional vector. An index value is calculated from the distribution of points, and based on the index value, a determination device for determining malignant or benign malignant pigment streak,
Index value registration means for storing the index value calculated from the digital color image of the nail plate pigment streak in association with the photographing time of the digital color image and stored in the index value data;
Reading the index value data, both the latest index value and the previous index value are lower than the threshold value, but if the latest index value is larger than the previous index value, it is determined as malignant and the previous index value exceeds the threshold value, but the latest When the index value is lower than the threshold value, a determination unit that determines that follow-up is necessary ,
A determination apparatus comprising: a result output means for outputting a determination result by the determination means to an output device. The determination means includes
Obtain the latest index value and the previous index value from the index value data,
When the latest index value and the previous index value are higher than a threshold value, or when the latest index value is higher than the previous index value, it is determined that the nail plate pigment streak is likely to be malignant. The determination apparatus according to claim 1. The determination means includes
Obtain the latest index value and the previous index value from the index value data,
When the latest index value and the previous index value are lower than a threshold value and the latest index value is lower than the previous index value, it is determined that the nail plate pigment streak is likely to be benign. 3. The determination device according to 1 or 2. The determination means includes
Obtaining a plurality of index values registered in the index value data, calculating a slope of transition of the plurality of index values over time;
The nail plate pigment streak is determined to have a high possibility of malignancy when all of the plurality of index values are higher than a threshold value or when the inclination is increasing. Judgment device. The determination means includes
Obtaining a plurality of index values registered in the index value data, calculating a slope of transition of the plurality of index values over time;
5. The nail plate pigment streak is determined to have a high possibility of benign when all of the plurality of index values are lower than a threshold value and the inclination tends to decrease. 5. Judgment device. The determination device according to any one of claims 1 to 5, wherein the determination unit determines malignancy or benign for a nail plate pigment streak other than a non-pigmented nail plate melanoma. When the digital color image is related to a child's nail plate pigment streak,
The determination apparatus according to any one of claims 1 to 6, wherein the result output means displays a transition of an index value calculated from the digital color image. The RGB parameter values of each pixel in the digital color image of the nail plate pigment line are regarded as a three-dimensional vector having these three components, and are defined based on latitude and longitude variables in the RGB space of the three-dimensional vector. An index value is calculated from the distribution of points, and based on the index value, a determination program for determining malignant or benign nail plate pigment streak,
Computer
Index value registration means for storing the index value calculated from the digital color image of the nail plate pigment streak in association with the photographing time of the digital color image and stored in the index value data;
Reading the index value data, both the latest index value and the previous index value are lower than the threshold value, but if the latest index value is larger than the previous index value, it is determined as malignant and the previous index value exceeds the threshold value, but the latest When the index value is lower than the threshold value, a determination unit that determines that follow-up is necessary ,
A determination program for causing a determination result by the determination means to function as a result output means for outputting to an output device. The determination means includes
Obtain the latest index value and the previous index value from the index value data,
When the latest index value and the previous index value are higher than a threshold value, or when the latest index value is higher than the previous index value, it is determined that the nail plate pigment streak is likely to be malignant. The determination program according to claim 8. The determination means includes
Obtain the latest index value and the previous index value from the index value data,
When the latest index value and the previous index value are lower than a threshold value and the latest index value is lower than the previous index value, it is determined that the nail plate pigment streak is likely to be benign. The determination program according to 8 or 9. The determination means includes
Obtaining a plurality of index values registered in the index value data, calculating a slope of transition of the plurality of index values over time;
The method according to claim 8, wherein when all of the plurality of index values are higher than a threshold value or when the inclination is increasing, it is determined that the nail plate pigment streak is likely to be malignant. Judgment program. The determination means includes
Obtaining a plurality of index values registered in the index value data, calculating a slope of transition of the plurality of index values over time;
The nail plate pigment streak is determined to have a high possibility of benign when all of the plurality of index values are lower than a threshold value and the inclination tends to decrease. Judgment program. The determination program according to any one of claims 8 to 12, wherein the determination unit determines malignancy or benign for a nail plate pigment streak other than a non-pigmented nail plate melanoma. When the digital color image is related to a child's nail plate pigment streak,
The determination program according to any one of claims 8 to 13, wherein the result output means displays a transition of an index value calculated from the digital color image.