Apparatus and method for diagnosing lymphedema

Abstract

According to the present embodiments, provided is an apparatus for diagnosing lymphedema, comprising: an input unit for receiving an input of 3D CT data of a body; a preprocessing unit for dividing the 3D CT data of the body into a plurality of parallel cross-sectional images; a calculation unit for calculating the volume of the body from the plurality of parallel cross-sectional images; and a determination unit for determining whether there is lymphedema on the basis of the volume calculated by the calculation unit, by using a rule-based algorithm for setting a rule between first data that is volume data of a plurality of people's bodies stored in a database, and second data that is data about whether the plurality of people have lymphedema, wherein the determination unit comprises a first determination unit for determining whether there is unilateral lymphedema and a second determination unit for determining whether there is bilateral lymphedema.

Description

Lymphedema diagnostic device and method

[0001] Embodiments of the present disclosure relate to a lymphedema diagnosis device and method that calculates a body volume from 3D CT data and determines whether lymphedema is present using a rule-based algorithm.

[0002] Lymphedema is a disease that causes swelling and chronic inflammation in the arms and legs due to the accumulation of fluid containing protein components in the interstitium as a result of damage to the lymphatic vessels. The number of cases is increasing due to the increase in the number of cancer surgeries and radiation therapy.

[0003] Measurement of arm or leg volume, essential for the diagnosis and analysis of treatment outcomes for lymphedema, has been problematic due to inaccuracy and high cost. Initially, volume was measured using the Archimedean method by submerging the affected area in water, but this method was limited in terms of convenience. Recently, the preferred method is to measure circumference at several points and convert this into a rough estimate, but this method has limitations in terms of accuracy. To overcome these limitations, some institutions are using perometers, but these are expensive and cost-prohibitive.

[0004] Accordingly, there is a need for a lymphedema diagnosis device and method that calculates the volume of the body from 3D CT data and determines whether lymphedema exists based on the calculated volume.

[0005] The present embodiments provide a lymphedema diagnosis device and method that can calculate the volume of a body from 3D CT data and increase the accuracy of determining whether or not lymphedema is present by using a rule-based algorithm.

[0006] In one aspect, a lymphedema diagnosis device according to one embodiment includes an input unit that receives 3D CT data of a body, a preprocessing unit that divides the 3D CT data of the body into a plurality of parallel cross-sectional images, a calculation unit that calculates a volume of the body from the plurality of parallel cross-sectional images, and a judgment unit that determines whether lymphedema exists based on the volume calculated by the calculation unit using a rule-based algorithm that sets a rule between first data, which is body volume data of a plurality of people stored in a database, and second data, which is data on whether a plurality of people have lymphedema, and the judgment unit includes a first judgment unit that determines whether unilateral lymphedema exists and a second judgment unit that determines whether bilateral lymphedema exists.

[0007] In another aspect, a method for diagnosing lymphedema according to another embodiment includes an input step of receiving 3D CT data of a body, a preprocessing step of dividing the 3D CT data of the body into a plurality of parallel cross-sectional images, a calculation step of calculating a volume of the body from the plurality of parallel cross-sectional images, and a judgment step of determining whether lymphedema exists based on the volume calculated in the calculation step using a rule-based algorithm that sets a rule between first data, which is body volume data of a plurality of people stored in a database, and second data, which is data on whether a plurality of people have lymphedema, and the judgment step includes a first judgment step of determining whether unilateral lymphedema exists and a second judgment step of determining whether bilateral lymphedema exists.

[0008] The lymphedema diagnosis device and method according to the present embodiments can calculate the volume of the body from 3D CT data and increase the accuracy of determining whether or not lymphedema is present by using a rule-based algorithm.

[0009] Figure 1 is a block diagram of a lymphedema diagnosis device according to one embodiment.

[0010] Figure 2 is a block diagram for explaining the rule-based algorithm used in the judgment unit of Figure 1.

[0011] Fig. 3 is a block diagram illustrating the judgment unit of Fig. 1.

[0012] Fig. 4 is a drawing exemplarily expressing the criteria of the bridge measured in the preprocessing unit of Fig. 1.

[0013] Figure 5 is a drawing exemplarily expressing a volume calculation method in the calculation section of Figure 1.

[0014] Figure 6 is a cross-sectional image showing muscles and subcutaneous tissue according to one embodiment.

[0015] Figure 7 is a drawing explaining the HU value, which is a standard for distinguishing between muscle and subcutaneous tissue in Figure 6.

[0016] Figure 8 is a flowchart of a method for diagnosing lymphedema according to another embodiment.

[0017] Figure 9 is a flowchart that concretizes the judgment step of Figure 8.

[0018] Figure 10 is another flowchart that embodies the judgment step of Figure 8.

[0019] Hereinafter, some embodiments of the present disclosure will be described in detail with reference to exemplary drawings. When adding reference numerals to components in each drawing, identical components may have the same numerals as much as possible even if they are shown in different drawings. In addition, when describing the present embodiments, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the technical idea of ​​the present invention, the detailed description may be omitted. When "includes," "has," "consists of," etc. are used in this specification, other parts may be added unless "only" is used. When a component is expressed in the singular, it may include a case in which the plural is included unless specifically stated otherwise.

[0020] Additionally, terms such as first, second, A, B, (a), (b), etc. may be used to describe components of the present disclosure. These terms are only intended to distinguish the components from other components, and the nature, order, sequence, or number of the components are not limited by the terms.

[0021] In a description of the positional relationship of components, when it is described that two or more components are "connected," "combined," or "connected," it should be understood that the two or more components may be directly "connected," "combined," or "connected," but that the two or more components may also be further "interposed" with another component to be "connected," "combined," or "connected." Here, the other component may be included in one or more of the two or more components that are "connected," "combined," or "connected" to each other.

[0022] In the description of the temporal flow relationship related to components, operation methods, or manufacturing methods, for example, when the temporal or flow relationship is described as “after”, “following”, “next to”, “before”, etc., it may also include cases where it is not continuous, unless “immediately” or “directly” is used.

[0023] Meanwhile, when numerical values ​​or corresponding information (e.g., levels, etc.) for components are mentioned, even without separate explicit description, the numerical values ​​or corresponding information may be interpreted as including an error range that may occur due to various factors (e.g., process factors, internal or external impact, noise, etc.).

[0024] The embodiments are described in detail with reference to the drawings below.

[0025] Figure 1 is a block diagram of a lymphedema diagnosis device according to one embodiment.

[0026] Referring to FIG. 1, a lymphedema diagnosis device (100) according to one embodiment includes an input unit (110) for receiving 3D CT data of a body, a preprocessing unit (120) for dividing the 3D CT data of the body into a plurality of parallel cross-sectional images, a calculation unit (130) for calculating a volume of the body from the plurality of parallel cross-sectional images, and a judgment unit (140) for determining whether or not lymphedema exists based on the volume calculated by the calculation unit (130) using a rule-based algorithm (160) that sets a rule between first data (151) which is body volume data of a plurality of people stored in a database (150) and second data (152) which is data on whether or not a plurality of people have lymphedema. The judgment unit (140) may include a first judgment unit (141) for determining whether or not unilateral lymphedema exists and a second judgment unit (142) for determining whether or not bilateral lymphedema exists.

[0027] The input unit (110) can input 3D CT data of the body as an input value. For example, the input value may be 3D CT data of an arm or a leg.

[0028] The preprocessing unit (120) can divide the 3D CT data of the body into a plurality of parallel cross-sectional images. For example, the preprocessing unit (120) can divide the 3D CT data of the body into a plurality of parallel cross-sectional images at 5 mm intervals.

[0029] The preprocessing unit (120) can distinguish body parts from 3D CT data of the body. The criteria for distinguishing body parts, for example, the criteria for distinguishing legs, may be from the split part of the leg to the tip of the toes.

[0030] The calculation unit (130) can calculate the cross-sectional area of ​​the body from each of a plurality of parallel cross-sectional images. Thereafter, the body volume can be calculated by adding the cross-sectional areas of the body or integrating them with respect to height. In particular, the Cavalieri method can be used to integrate the cross-sectional area of ​​the body with respect to height.

[0031] The judgment unit (140) can determine whether lymphedema exists based on the body volume calculated by the calculation unit (130). At this time, a rule-based algorithm (160) can be used to determine whether lymphedema exists. The rule-based algorithm (160) can be an algorithm that sets a rule between first data (151), which is body volume data of multiple people stored in a database (150), and second data (152), which is data on whether multiple people have lymphedema. Lymphedema can be unilateral lymphedema or bilateral lymphedema. The judgment unit (140) can determine whether unilateral lymphedema exists using the rule-based algorithm (160), and then determine whether bilateral lymphedema exists.

[0032] Figure 2 is a block diagram for explaining the rule-based algorithm used in the judgment unit of Figure 1.

[0033] Referring to FIG. 2, the database (150) may include first data (151) and second data (152). Based on the database (150), statistical analysis may be performed to establish a lymphedema judgment criterion or threshold ratio described below.

[0034] The first data (151) is volume data of each body of a plurality of people. The first data (151) may be volume data of the body measured from 3D CT data, but is not limited thereto. For example, the first data (151) may be volume data of the body measured through the Archimedean method, a perometer, MRI (Magnetic Resonance Imaging), etc. The second data (152) is data on whether each of the plurality of people has lymphedema. For example, the second data (152) may be data on whether a specific person among the plurality of people has been diagnosed with lymphedema (positive) or has been diagnosed as normal (negative).

[0035] The first data (151) and the second data (152) may correspond to each other. For example, data in which the corresponding second data (152) value among the first data (151) is negative refers to the volume data of the body of a person whose lymphedema diagnosis result is negative.

[0036] A rule can be established between the first data (151) and the second data (152) stored in the database (150) through a rule-based algorithm (160). The rule established through the rule-based algorithm (160) can include a critical ratio, which is a criterion for determining whether lymphedema exists. The critical ratio can be a ratio that serves as a criterion for determining whether lymphedema exists, with respect to the volume of the larger body compared to the volume of the smaller body among the left and right parts of the body. Alternatively, it can be a ratio that serves as a criterion for determining whether lymphedema exists, with respect to the body volume calculated by the calculation unit (130) compared to the average value of the body volume of which the corresponding second data (152) value among the first data (151) is negative. Alternatively, it can be a ratio that serves as a criterion for determining whether lymphedema exists, with respect to the volume ratio of the muscle (170) to the subcutaneous tissue (180) calculated by the calculation unit (130).

[0037] For example, the critical ratio may be the ratio of the maximum value among the first data (151) to the average value of the first data (151). In other words, the critical ratio may be the ratio of the maximum value among the body volumes of the plurality of people to the average value of the body volumes of the plurality of people, or the ratio of the top 10% among the body volumes of the plurality of people to the average value of the body volumes of the plurality of people. In this case, the average value and the maximum value may be the average value and the maximum value of data whose corresponding second data (152) value among the first data (151) is negative, but is not limited thereto. For example, the average value or the maximum value may be the average value or the maximum value of data whose corresponding second data (152) value among the first data (151) is negative, with outliers removed. Outliers may mean values ​​that deviate by more than 1.5 times the difference between the 1st quartile (the value that is the lower 25%) and the 3rd quartile (the value that is the upper 25%), but are not limited thereto. That is, the critical ratio may be the maximum value compared to the average of the entire data, or the maximum value compared to the average after removing a certain percentage of outliers, or the value corresponding to a certain percentage of the upper value compared to the average of the entire data, or the value corresponding to a certain percentage of the upper value compared to the average after removing a certain percentage of outliers. In one embodiment, the critical ratio may be the ratio of the maximum value to the average value of the body volume.

[0038] The optimal method among the various methods described above can be selected to set the critical ratio. This allows for a more accurate assessment of lymphedema. While the method for setting the critical ratio, i.e., the rule established through the rule-based algorithm, has been described, the present invention is not limited thereto. For example, the critical ratio has been described as the maximum value or a specific upper value relative to the average value of the first data (151), but it can also be the minimum value or a specific lower value.

[0039] The rules set through the rule-based algorithm (160) may include rules for determining whether unilateral lymphedema exists and then determining whether bilateral lymphedema exists. Unilateral lymphedema is a disease in which the volume of one side of the body increases compared to the volume of the other side of the body. Therefore, the presence of lymphedema can be determined by calculating the volume of the other side of the body compared to the volume of the other side. In this case, the rules for determining whether unilateral lymphedema exists may include rules for comparing the ratio of the volume of the larger side of the body to the volume of the smaller side of the body with a threshold ratio set in advance based on the first data (151).

[0040] Afterwards, the presence of bilateral lymphedema can be determined. Bilateral lymphedema is a disease in which the volume of both the left and right sides of the body increases. At this time, the rule for determining the presence of bilateral lymphedema may include a rule for comparing the volume of the left and right sides calculated by the calculation unit (130) or the volume ratio of muscle (170) to subcutaneous fat (180) with a threshold ratio set in advance based on the first data (151).

[0041] Fig. 3 is a block diagram illustrating the judgment unit of Fig. 1.

[0042] Referring to Fig. 3, the judgment unit (140) may include a first judgment unit (141) and a second judgment unit (142). The judgment unit (140) may determine whether unilateral lymphedema exists in the first judgment unit (141), and then determine whether bilateral lymphedema exists in the second judgment unit (142). The first judgment unit (141) may compare the volume of the left body and the volume of the right body calculated in the calculation unit (130). The first judgment unit (141) may determine unilateral lymphedema if the ratio of the volume of the larger side to the volume of the smaller side is greater than or equal to a first threshold ratio. The first critical ratio may be the ratio of the maximum value that the volume of one body whose corresponding second data (152) value among the first data (151) stored in the database (150) is negative to the average value of the volume of one body whose corresponding second data (152) value among the first data (151) is negative can have, but is not limited thereto.

[0043] If the volume of one body calculated in the calculation unit (130) is greater than the average volume of one body for which the corresponding second data (152) among the first data (151) is negative, the standard for determining whether unilateral lymphedema exists may be the first critical ratio. If the average volume of one body for which the corresponding second data (152) among the first data (151) is negative is a, and the maximum value that the volume of one body for which the corresponding second data (152) among the first data (151) is negative is b, the first critical ratio means b / a. For example, if the average volume of one leg whose corresponding second data (152) value among the first data (151) is negative is 300 ml, and the maximum value that the volume of one leg whose corresponding second data (152) value among the first data (151) is negative can have is 330 ml, the first critical ratio may be 1.1, but is not limited thereto.

[0044] If the volume of one side of the body calculated by the calculation unit (130) is smaller than the average volume of one side of the body for which the corresponding second data (152) among the first data (151) is negative, the first judgment unit (141) can determine whether there is unilateral lymphedema of the body, for example, the leg, based on the absolute value of 200 ml. For example, if the volume of one side of the body calculated by the calculation unit (130) is 220 ml, and the average volume of one side of the body for which the corresponding second data (152) among the first data (151) is negative is 300 ml, the first judgment unit (141) can determine this as unilateral lymphedema because the volume of one side of the body calculated by the calculation unit (130) is greater than or equal to the absolute value of 200 ml.

[0045] The statistical values ​​of the database (150) used to determine whether there is unilateral lymphedema, for example, the average or maximum value of the volume of one leg in which the corresponding second data (152) among the first data (151) is negative, may be the average or maximum value of people with the same BMI or height as the subject to be determined to have lymphedema. In other words, the average or maximum value of the first data (151) when the second data (152) is normal may differ by BMI or height. Accordingly, the first critical ratio may be set differently by BMI section or height section. Through this, by comparing data of people with similar body conditions, the accuracy of determining whether there is lymphedema can be increased.

[0046] In one embodiment, the second judgment unit (142) can determine whether there is unilateral lymphedema, and if not, whether there is bilateral lymphedema. The second judgment unit (142) can compare the body volume calculated by the calculation unit (130) with the average volume of the body for which the corresponding second data (152) value among the first data (151) is negative to determine whether there is bilateral lymphedema. The second judgment unit (142) can determine bilateral lymphedema if the body volume calculated by the calculation unit (130) is greater than the average volume of the body for which the corresponding second data (152) value among the first data (151) is negative, and if the body volume calculated by the calculation unit (130) is greater than a preset second threshold ratio of the average volume of the body for which the corresponding second data (152) value among the first data (151) is negative. The second critical ratio may be the ratio of the maximum value that the volume of both bodies whose corresponding second data (152) value among the first data (151) stored in the database (150) is negative to the average value of the volume of both bodies whose corresponding second data (152) value among the first data (151) is negative can have, but is not limited thereto.

[0047] If the volume of both legs is greater than the average volume of both legs for which the corresponding second data (152) value among the first data (151) is negative, the criterion for determining whether or not bilateral lymphedema exists may be the second critical ratio. If the average volume of both bodies for which the corresponding second data (152) value among the first data (151) is negative is c, and the maximum value that the volume of both bodies for which the corresponding second data (152) value among the first data (151) is negative is d, the second critical ratio means d / c. For example, if the average volume of both bodies for which the corresponding second data (152) value among the first data (151) is negative is 600 ml, and the maximum value that the volume of both bodies for which the corresponding second data (152) value among the first data (151) is negative is 660 ml, the second critical ratio may be 1.1, but is not limited thereto.

[0048] If the volume of both legs calculated by the calculation unit (130) is smaller than the average volume of both legs for which the corresponding second data (152) among the first data (151) is negative, the second judgment unit (142) can determine whether or not there is bilateral lymphedema in the body, for example, the legs, based on the absolute value of 400 ml. For example, if the volume of both legs calculated by the calculation unit (130) is 440 ml, and the average volume of both legs for which the corresponding second data (152) among the first data (151) is negative is 600 ml, the second judgment unit (142) can determine this as bilateral lymphedema because the volume of both legs calculated by the calculation unit (130) is 400 ml or more.

[0049] As described above, the statistical values ​​of the database (150) used to determine whether or not there is bilateral lymphedema, for example, the average or maximum volume of both legs for which the corresponding second data (152) value among the first data (151) is negative, may be data of people having the same BMI or height as the subject for whom it is desired to determine whether or not there is lymphedema.

[0050] In another embodiment, the second judgment unit (142) may compare the volume ratio of the muscle (170) to the subcutaneous tissue (180) calculated by the calculation unit (130) with the volume ratio of the muscle (170) to the subcutaneous tissue (180) whose corresponding second data (152) value among the first data (151) is negative to determine whether bilateral lymphedema exists. The second judgment unit (142) may determine bilateral lymphedema if the volume ratio of the muscle (170) to the subcutaneous tissue (180) calculated by the calculation unit (130) is equal to or lower than the third threshold ratio. The third critical ratio may be, but is not limited to, the ratio of the maximum volume that a muscle (170) having a negative corresponding second data (152) value among the first data (151) can have to the minimum volume that a subcutaneous tissue (180) having a negative corresponding second data (152) value among the first data (151) can have.

[0051] For example, if the maximum value that the volume of the muscle (170) whose corresponding second data (152) value among the first data (151) is negative can have is 100 ml, and the minimum value that the volume of the subcutaneous tissue (180) whose corresponding second data (152) value among the first data (151) is negative can have is 210 ml, the third critical ratio may be 2.1, but is not limited thereto.

[0052] As described above, the statistical values ​​of the database (150) used to determine whether or not there is bilateral lymphedema, for example, the maximum value that the volume of the muscle (170) that has a negative corresponding second data (152) value among the first data (151) or the minimum value that the volume of the subcutaneous tissue (180) can have, may be data of people who have a BMI or height in the same range as the subject whose presence or absence of lymphedema is to be determined.

[0053] Fig. 4 is a drawing exemplarily expressing the reference (B) of the bridge measured in the preprocessing unit of Fig. 1.

[0054] Referring to Fig. 4, the standard for distinguishing the legs by the preprocessing unit (120) may be from the part where the legs are split to the tip of the toes. A clear standard for distinguishing the body may be necessary to measure volume from 3D data. However, if the standard for distinguishing the legs is from the pelvis to the tip of the toes, the overall measured volume may increase compared to using the standard from the part where the legs are split to the tip of the toes, which may reduce the sensitivity of the data. Furthermore, if the standard for distinguishing the legs is set from the pelvis to the tip of the toes, it may be difficult to clearly establish the standard for the legs. Therefore, by distinguishing the legs from the part where the legs are split to the tip of the toes, volume measurement of lymphedema patients can be performed more accurately.

[0055] Figure 5 is a drawing exemplarily expressing a volume calculation method in the calculation section of Figure 1.

[0056] Referring to Fig. 5, an example of measuring the volume of a breast using the Cavalieri Method can be confirmed. The Cavalieri Method uses the principle that if the ratio of the cross-sections is constant, the ratio of the whole is also constant, and the volume of a three-dimensional figure can be obtained based on this method. The calculation unit (130) can calculate the cross-sectional area (A) and height (H) of each of a plurality of parallel cross-sectional images, and then integrate the cross-sectional area (A) with respect to the height (H) to calculate the volume of the body. For example, the height (H) of a plurality of parallel unit volumes may be 5 mm, but is not limited thereto.

[0057] Fig. 6 is a cross-sectional image showing muscles and subcutaneous tissue according to one embodiment. Fig. 7 is a diagram explaining the HU value, which is a standard for distinguishing muscles and subcutaneous tissue in Fig. 6.

[0058] Referring to FIGS. 6 and 7, it can be confirmed that the brightness of the muscle (170) and the subcutaneous tissue (180) are different on the cross-sectional image of FIG. 6. The muscle (170) and the subcutaneous tissue (180) can be distinguished on the cross-sectional image based on the HU value provided in the 3D CT data. FIG. 7 is a simplified diagram of the HU value, and shows an example of the HU value in which the HU value of the muscle (soft tissue) is 30 to 45 and the HU value of the subcutaneous tissue (fat) is -100, but is not limited thereto. Using the HU value, the area of ​​the muscle (170) or the subcutaneous tissue (180) can be distinguished from a plurality of parallel cross-sectional images, and the volume of the muscle (170) or the subcutaneous tissue (180) can be obtained, respectively, by the calculation unit (130) through the volume calculation method described above. From this, the volume ratio of the muscle (170) to the subcutaneous tissue (180) can be obtained, which can be used to determine whether there is lymphedema.

[0059] Figure 8 is a flowchart of a method for diagnosing lymphedema according to another embodiment.

[0060] Referring to FIG. 8, a lymphedema diagnosis method (200) according to another embodiment includes an input step (S110) of receiving 3D CT data of a body, a preprocessing step (S120) of dividing the 3D CT data of the body into a plurality of parallel cross-sectional images, a calculation step (S130) of calculating a volume of the body from the plurality of parallel cross-sectional images, and a judgment step (S140) of determining whether or not lymphedema exists based on the volume calculated in the calculation step (S130) using a rule-based algorithm (160) that sets a rule between first data (151) which is body volume data of a plurality of people stored in a database (150) and second data (152) which is data on whether or not a plurality of people have lymphedema. The judgment step (S140) may include a first judgment step of determining whether or not unilateral lymphedema exists and a second judgment step of determining whether or not bilateral lymphedema exists.

[0061] The input step (S110) can input 3D CT data of the body as an input value. For example, the input value may be 3D CT data of an arm or a leg.

[0062] The preprocessing step (S120) can divide the 3D CT data of the body into multiple parallel cross-sectional images. For example, the preprocessing step (S120) can divide the 3D CT data of the body into multiple parallel cross-sectional images spaced 5 mm apart.

[0063] The preprocessing step (S120) can identify body parts from 3D CT data. For example, the criteria for identifying a leg could be the distance from the split of the leg to the tip of the toe.

[0064] The calculation step (S130) can calculate the cross-sectional area of ​​the body from each of multiple parallel cross-sectional images. The body volume can then be calculated by adding the cross-sectional areas or integrating them with respect to height. In particular, the Cavalieri method can be used to integrate the cross-sectional area with respect to height.

[0065] The determination step (S140) can determine whether lymphedema exists based on the body volume calculated in the calculation step (S130). At this time, a rule-based algorithm (160) can be used to determine whether lymphedema exists. The rule-based algorithm (160) can be an algorithm that sets a rule between first data (151), which is body volume data of multiple people stored in a database (150), and second data (152), which is data on whether multiple people have lymphedema. Lymphedema can be unilateral lymphedema or bilateral lymphedema. The determination step (S140) can determine whether unilateral lymphedema exists using the rule-based algorithm (160), and then determine whether bilateral lymphedema exists.

[0066] Figure 9 is a flowchart that concretizes the judgment step of Figure 8.

[0067] Referring to FIG. 9, the determination step (S140) may include a rule-based algorithm (160) for determining whether unilateral or bilateral lymphedema exists. The rule-based algorithm (160) may set rules between first data (151) and second data (152) stored in the database (150). Statistical analysis may be performed based on the database (150) to set a lymphedema determination criterion or critical ratio to be described later. The first data (151) is volume data of each body of a plurality of people. The first data (151) may be volume data of a body measured from 3D CT data, but is not limited thereto. For example, the first data (151) may be volume data of a body measured through the Archimedean method, a perometer, MRI (Magnetic Resonance Imaging), etc. The second data (152) is data on whether each of the plurality of people has lymphedema. For example, the second data (152) may be data on whether a specific person among a plurality of people was diagnosed with lymphedema (positive) or was diagnosed as normal (negative).

[0068] The first data (151) and the second data (152) may correspond to each other. For example, data in which the corresponding second data (152) value among the first data (151) is negative refers to the volume data of the body of a person whose lymphedema diagnosis result is negative.

[0069] The rule set through the rule-based algorithm (160) may include a critical ratio, which is a standard for determining whether lymphedema exists. The critical ratio may be a ratio that serves as a standard for determining whether lymphedema exists, with respect to the volume of the larger body compared to the volume of the smaller body among the left and right parts of the body. Alternatively, it may be a ratio that serves as a standard for determining whether lymphedema exists, with respect to the body volume calculated in the calculation step (S130) compared to the average value of the body volume for which the corresponding second data (152) among the first data (151) is negative. Alternatively, it may be a ratio that serves as a standard for determining whether lymphedema exists, with respect to the volume ratio of the muscle (170) to the subcutaneous tissue (180) calculated in the calculation step (S130).

[0070] For example, the critical ratio may be the ratio of the maximum value among the first data (151) to the average value of the first data (151). In other words, the critical ratio may be the ratio of the maximum value among the body volumes of the plurality of people to the average value of the body volumes of the plurality of people, or the ratio of the top 10% among the body volumes of the plurality of people to the average value of the body volumes of the plurality of people. In this case, the average value and the maximum value may be the average value and the maximum value of data whose corresponding second data (152) value among the first data (151) is negative, but is not limited thereto. For example, the average value or the maximum value may be the average value or the maximum value of data whose corresponding second data (152) value among the first data (151) is negative, with outliers removed. Outliers may mean values ​​that deviate by more than 1.5 times the difference between the 1st quartile (the value that is the lower 25%) and the 3rd quartile (the value that is the upper 25%), but are not limited thereto. That is, the critical ratio may be the maximum value compared to the average of the entire data, or the maximum value compared to the average after removing a certain percentage of outliers, or the value corresponding to a certain percentage of the upper value compared to the average of the entire data, or the value corresponding to a certain percentage of the upper value compared to the average after removing a certain percentage of outliers. In one embodiment, the critical ratio may be the ratio of the maximum value to the average value of the body volume.

[0071] The optimal method among the various methods described above can be selected to set the critical ratio. This allows for a more accurate assessment of lymphedema. While the method for setting the critical ratio, i.e., the rule established through the rule-based algorithm, has been described, the present invention is not limited thereto. For example, the critical ratio has been described as the maximum value or a specific upper value relative to the average value of the first data (151), but it can also be the minimum value or a specific lower value.

[0072] The rules set through the rule-based algorithm (160) may include rules for determining whether unilateral lymphedema exists and then determining whether bilateral lymphedema exists. Unilateral lymphedema is a disease in which the volume of one side of the body increases compared to the volume of the other side of the body. Therefore, the presence of lymphedema can be determined by calculating the volume of the other side of the body compared to the volume of the other side. In this case, the rules for determining whether unilateral lymphedema exists may include rules for comparing the ratio of the volume of the larger side of the body to the volume of the smaller side of the body with a threshold ratio set in advance based on the first data (151).

[0073] Afterwards, the presence of bilateral lymphedema can be determined. Bilateral lymphedema is a disease in which the volume of both the left and right sides of the body increases. At this time, the rule for determining the presence of bilateral lymphedema may include a rule for comparing the volume of the left and right sides calculated in the calculation step (S130) with a threshold ratio set in advance based on the first data (151).

[0074] Referring back to FIG. 9, the determination step (S140) may include a first determination step and a second determination step. The determination step (S140) may determine whether unilateral lymphedema exists in the first determination step, and then determine whether bilateral lymphedema exists in the second determination step. The first determination step may compare the volume of the left body and the volume of the right body calculated in the calculation step (S130). The first determination step may determine unilateral lymphedema if the ratio of the larger volume to the smaller volume is equal to or greater than a first threshold ratio. The first threshold ratio may be, but is not limited to, the ratio of the maximum value that the volume of one body whose corresponding second data (152) value among the first data (151) stored in the database (150) can have to the average value of the volume of one body whose corresponding second data (152) value is negative.

[0075] In the calculation step (S130), if the volume of one body calculated is greater than the average volume of one body for which the corresponding second data (152) among the first data (151) is negative, the standard for determining whether unilateral lymphedema exists may be the first critical ratio. If the average volume of one body for which the corresponding second data (152) among the first data (151) is negative is a, and the maximum value that the volume of one body for which the corresponding second data (152) among the first data (151) is negative is b, the first critical ratio means b / a. For example, if the average volume of one leg whose corresponding second data (152) value among the first data (151) is negative is 300 ml, and the maximum value that the volume of one leg whose corresponding second data (152) value among the first data (151) is negative can have is 330 ml, the first critical ratio may be 1.1, but is not limited thereto.

[0076] In the calculation step (S130), if the volume of one side of the body calculated is smaller than the average value of the volume of one side of the body for which the corresponding second data (152) among the first data (151) is negative, the first judgment step can determine whether there is unilateral lymphedema of the body, for example, the leg, based on the absolute value of 200 ml. For example, in the calculation step (S130), if the volume of one side of the body calculated is 220 ml, and the average value of the volume of one side of the body for which the corresponding second data (152) among the first data (151) is negative is 300 ml, since the volume of one side of the body calculated in the calculation step (S130) is greater than or equal to the absolute value of 200 ml, the first judgment step can determine this as unilateral lymphedema.

[0077] The statistical values ​​of the database (150) used to determine whether there is unilateral lymphedema, for example, the average or maximum value of the volume of one leg in which the corresponding second data (152) among the first data (151) is negative, may be the average or maximum value of people with the same BMI or height as the subject to be determined to have lymphedema. In other words, the average or maximum value of the first data (151) when the second data (152) is normal may differ by BMI or height. Accordingly, the first critical ratio may be set differently by BMI section or height section. Through this, by comparing data of people with similar body conditions, the accuracy of determining whether there is lymphedema can be increased.

[0078] In one embodiment, the second determination step may determine whether there is unilateral lymphedema, and if not, whether there is bilateral lymphedema. The second determination step may compare the body volume calculated in the calculation step (S130) with the average volume of the body for which the corresponding second data (152) value among the first data (151) is negative to determine whether there is bilateral lymphedema. In the second determination step, if the body volume calculated in the calculation step (S130) is greater than the average volume of the body for which the corresponding second data (152) value among the first data (151) is negative, and if the body volume calculated in the calculation step (S130) is greater than a preset second threshold ratio of the average volume of the body for which the corresponding second data (152) value among the first data (151) is negative, bilateral lymphedema may be determined. The second critical ratio may be the ratio of the maximum value that the volume of both bodies whose corresponding second data (152) value among the first data (151) stored in the database (150) is negative to the average value of the volume of both bodies whose corresponding second data (152) value among the first data (151) is negative can have, but is not limited thereto.

[0079] If the volume of both legs is greater than the average volume of both legs for which the corresponding second data (152) value among the first data (151) is negative, the criterion for determining whether or not bilateral lymphedema exists may be the second critical ratio. If the average volume of both bodies for which the corresponding second data (152) value among the first data (151) is negative is c, and the maximum value that the volume of both bodies for which the corresponding second data (152) value among the first data (151) is negative is d, the second critical ratio means d / c. For example, if the average volume of both bodies for which the corresponding second data (152) value among the first data (151) is negative is 600 ml, and the maximum value that the volume of both bodies for which the corresponding second data (152) value among the first data (151) is negative is 660 ml, the second critical ratio may be 1.1, but is not limited thereto.

[0080] In the calculation step (S130), if the volume of both legs calculated is smaller than the average value of the volume of both legs for which the corresponding second data (152) among the first data (151) is negative, the second judgment step can determine whether or not there is bilateral lymphedema of the body, for example, the legs, based on the absolute value of 400 ml. For example, in the calculation step (S130), if the volume of both legs calculated is 440 ml, and the average value of the volume of both legs for which the corresponding second data (152) among the first data (151) is negative is 600 ml, since the volume of both legs calculated in the calculation step (S130) is 400 ml or more, the second judgment step can determine this as bilateral lymphedema.

[0081] As described above, the statistical values ​​of the database (150) used to determine whether or not there is bilateral lymphedema, for example, the average or maximum volume of both legs for which the corresponding second data (152) value among the first data (151) is negative, may be data of people having the same BMI or height as the subject for whom it is desired to determine whether or not there is lymphedema.

[0082] Figure 10 is another flowchart that embodies the judgment step of Figure 8.

[0083] Referring to FIG. 10, a rule for determining whether there is bilateral lymphedema according to another embodiment may include a rule for comparing the volume ratio of muscle (170) to subcutaneous tissue (180) calculated in the calculation step (S130) with a threshold ratio set in advance based on the first data (151).

[0084] As described above, the method for determining whether unilateral lymphedema exists in the first determination step may be equivalent to or similar to the method described in Fig. 9. After determining whether unilateral lymphedema exists in the first determination step, if it is not unilateral lymphedema, the method for determining whether bilateral lymphedema exists may be performed in the second determination step.

[0085] In another embodiment, the second determination step may compare the volume ratio of the muscle (170) to the subcutaneous tissue (180) calculated in the calculation step (S130) with the volume ratio of the muscle (170) to the subcutaneous tissue (180) for which the corresponding second data (152) among the first data (151) is negative to determine whether there is bilateral lymphedema. The second determination step may determine bilateral lymphedema if the volume ratio of the muscle (170) to the subcutaneous tissue (180) calculated in the calculation step (S130) is less than or equal to a third threshold ratio. The third threshold ratio may be, but is not limited to, the ratio of the maximum volume that the muscle (170) for which the corresponding second data (152) among the first data (151) is negative can have to the minimum volume that the subcutaneous tissue (180) for which the corresponding second data (152) among the first data (151) is negative can have.

[0086] For example, if the maximum value that the volume of the muscle (170) whose corresponding second data (152) value among the first data (151) is negative can have is 100 ml, and the minimum value that the volume of the subcutaneous tissue (180) whose corresponding second data (152) value among the first data (151) is negative can have is 210 ml, the third critical ratio may be 2.1, but is not limited thereto.

[0087] As described above, the statistical values ​​of the database (150) used to determine whether or not there is bilateral lymphedema, for example, the maximum value that the volume of the muscle (170) that has a negative corresponding second data (152) value among the first data (151) or the minimum value that the volume of the subcutaneous tissue (180) can have, may be data of people who have a BMI or height in the same range as the subject whose presence or absence of lymphedema is to be determined.

[0088] The lymphedema diagnosis method (200) according to another embodiment described with reference to FIGS. 8 to 10 can apply the contents described in the lymphedema diagnosis device (100) according to one embodiment described with reference to FIGS. 1 to 7 in the same or similar manner.

[0089] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will readily appreciate that the present invention can be readily modified into other specific forms without altering the technical spirit or essential characteristics of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single entity may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined manner.

[0090] The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

[0091] The above description is merely an illustrative example of the technical idea of ​​the present disclosure, and those skilled in the art to which the present disclosure pertains will appreciate that various modifications and variations can be made without departing from the essential characteristics of the technical idea of ​​the present disclosure. In addition, the present embodiments are not intended to limit the technical idea of ​​the present disclosure but rather to explain it, and therefore the scope of the technical idea of ​​the present disclosure is not limited by these embodiments. The scope of protection of the present disclosure should be interpreted by the claims below, and all technical ideas within a scope equivalent thereto should be interpreted as being included within the scope of the rights of the present disclosure.

[0092]

[0093] CROSS-REFERENCE TO RELATED APPLICATION

[0094] This patent application claims priority under 35 USC §119(a) to Korean Patent Application No. 10-2024-0080917, filed June 21, 2024, the entire contents of which are incorporated herein by reference. Furthermore, this patent application claims priority in countries other than the United States for the same reasons, the entire contents of which are incorporated herein by reference.

Claims

1. Input section for receiving 3D CT data of the body; A preprocessing unit that divides the 3D CT data of the above body into a plurality of parallel cross-sectional images; A calculation unit for calculating the volume of the body from the plurality of parallel cross-sectional images; and A judgment unit that determines whether lymphedema exists based on the volume calculated by the calculation unit using a rule-based algorithm that sets a rule between first data, which is body volume data of a plurality of people stored in a database, and second data, which is data on whether the plurality of people have lymphedema, is included. A lymphedema diagnostic device, wherein the above-mentioned judgment unit includes a first judgment unit that determines whether unilateral lymphedema exists and a second judgment unit that determines whether bilateral lymphedema exists.

2. In paragraph 1, The above first judgment unit compares the volume of the left body and the volume of the right body calculated by the calculation unit to determine whether there is unilateral lymphedema, A lymphedema diagnostic device that determines unilateral lymphedema when the ratio of the larger volume to the smaller volume is greater than the first critical ratio.

3. In paragraph 2, The above first critical ratio is a lymphedema diagnosis device that is a ratio of the maximum value that the volume of one body whose corresponding second data value among the first data is negative can have to the average volume of one body whose corresponding second data value among the first data is negative.

4. In paragraph 1, The second judgment unit compares the body volume calculated by the calculation unit with the average value of the body volume for which the corresponding second data value among the first data is negative to determine whether or not there is bilateral lymphedema. A lymphedema diagnosis device that determines bilateral lymphedema when the volume of the body calculated by the calculation unit is greater than the average volume of the body for which the corresponding second data value among the first data is negative, and the volume of the body calculated by the calculation unit is greater than or equal to the second threshold ratio compared to the average volume of the body for which the corresponding second data value among the first data is negative.

5. In paragraph 4, The above second critical ratio is a lymphedema diagnosis device in which the ratio of the maximum value that the volume of both bodies for which the corresponding second data value among the stored first data is negative is to the average value of the volume of both bodies for which the corresponding second data value among the stored first data is negative is possible.

6. In paragraph 1, The second judgment unit compares the muscle-to-subcutaneous tissue volume ratio calculated by the calculation unit with the muscle-to-subcutaneous tissue volume ratio for which the corresponding second data value among the first data is negative to determine whether there is bilateral lymphedema. A lymphedema diagnostic device that determines bilateral lymphedema when the volume ratio of muscle to subcutaneous tissue calculated in the above calculation section is below the third critical ratio.

7. In paragraph 6, The above third critical ratio is a lymphedema diagnosis device that is a ratio of the maximum volume that a muscle can have for which the corresponding second data value among the first data is negative to the minimum volume that a subcutaneous tissue can have for which the corresponding second data value among the first data is negative.

8. In paragraph 6, The above judgment unit is a lymphedema diagnostic device that distinguishes between the muscles and subcutaneous tissues according to the HU value.

9. In paragraph 1, The above preprocessing unit is a lymphedema diagnosis device that divides the 3D CT data of the body into a plurality of parallel cross-sectional images at intervals of 5 mm.

10. In paragraph 1, The above preprocessing unit distinguishes arms or legs from the 3D CT data of the body, A lymphedema diagnostic device that divides the legs based on the split part of the leg to the tip of the toes.

11. In paragraph 1, A lymphedema diagnosis device in which the calculation unit calculates the cross-sectional area of ​​the body from each of the plurality of parallel cross-sectional images, and calculates the volume of the body by adding the cross-sectional areas or integrating them with respect to the height.

12. Input stage for receiving 3D CT data of the body; A preprocessing step of dividing the 3D CT data of the above body into multiple parallel cross-sectional images; A calculation step of calculating the volume of the body from the plurality of parallel cross-sectional images; and A judgment step for judging whether lymphedema exists based on the volume calculated in the calculation step using a rule-based algorithm that sets a rule between first data, which is data on the body volume of a plurality of people stored in a database, and second data, which is data on whether the plurality of people have lymphedema, A method for diagnosing lymphedema, wherein the above-mentioned judgment step includes a first judgment step for determining whether unilateral lymphedema exists and a second judgment step for determining whether bilateral lymphedema exists.

13. In paragraph 12, The above first judgment step compares the volume of the left body and the volume of the right body calculated in the above calculation step to determine whether there is unilateral lymphedema. A method for diagnosing lymphedema in which the ratio of the larger volume to the smaller volume is greater than the first critical ratio, is determined to be unilateral lymphedema.

14. In paragraph 13, The above first critical ratio is a method for diagnosing lymphedema, wherein the ratio is the maximum value that the volume of one body whose corresponding second data value among the first data is negative can have to the average volume of one body whose corresponding second data value among the first data is negative.

15. In paragraph 12, The second judgment step compares the body volume calculated in the calculation step with the average volume of the body for which the corresponding second data value among the first data is negative to determine whether or not there is bilateral lymphedema. A method for diagnosing lymphedema, wherein the volume of the body calculated in the above calculation step is greater than the average volume of the body for which the corresponding second data value among the first data is negative, and the volume of the body calculated in the above calculation step is greater than or equal to a second threshold ratio compared to the average volume of the body for which the corresponding second data value among the first data is negative, is determined to be bilateral lymphedema.

16. In paragraph 5, The above second critical ratio is a method for diagnosing lymphedema, wherein the ratio is the maximum value that the volume of both bodies, for which the corresponding second data value among the stored first data is negative, can have, to the average volume of both bodies, for which the corresponding second data value among the stored first data is negative.

17. In paragraph 12, The second judgment step compares the muscle-to-subcutaneous tissue volume ratio calculated in the calculation step with the muscle-to-subcutaneous tissue volume ratio for which the corresponding second data value among the first data is negative to determine whether there is bilateral lymphedema. A method for diagnosing lymphedema by determining that bilateral lymphedema is present when the volume ratio of muscle to subcutaneous tissue calculated in the above calculation step is less than or equal to the third critical ratio.

18. In paragraph 17, The third critical ratio is a method for diagnosing lymphedema, wherein the ratio is the maximum volume that a muscle can have for which the corresponding second data value among the first data is negative, to the minimum volume that a subcutaneous tissue can have for which the corresponding second data value among the first data is negative.

19. In paragraph 12, The above preprocessing step distinguishes arms or legs from the 3D CT data of the body, A method of diagnosing lymphedema by dividing the legs based on the split part of the leg to the tip of the toes.

20. In paragraph 12, The above calculation step is a method for diagnosing lymphedema, wherein the cross-sectional area of ​​the body is calculated from each of the plurality of parallel cross-sectional images, and the volume of the body is calculated by adding the cross-sectional areas or integrating them with respect to the height.

Images