JP2007159699A - Trunk visceral fat measuring method and instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure the measurement sensitivity of visceral fat tissue and to secure the optimum S/N condition of a four-electrode technique. <P>SOLUTION: By arranging one of a current application electrode pair at a navel position and arranging the other at the back navel circumference or in the lumbar division in a slightly lower side of the back navel circumference, a current energizing amount to the splanchnic organ tissue and the visceral fat tissue in the inside of a skeletal muscle tissue layer is increased. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a trunk visceral fat measurement method and apparatus.

  Body fat tissue estimation technology using bioelectrical impedance has spread to the world as a technique for measuring body fat tissue volume and body fat percentage, but in reality, it is not directly measuring fat tissue. In addition, it is an electrical measurement of lean tissue in which water other than adipose tissue is dominant. In particular, in the whole body measurement, the conventional type models one hand-one leg with a single cylinder in the supine position (one-hand-one leg guidance method). Measure between both palms to measure, guide between both legs integrated with weight scale, upper and lower limbs, upper and lower limbs and trunk, or left and right upper limbs, left and right lower limbs, trunk as 5 segments The technique of measuring the impedance by making it possible to apply a cylindrical model separately has also become apparent. In addition, a patent application has been filed for a measurement technique for estimating the visceral fat tissue volume by simplifying the impedance CT measurement technique, measuring the abdominal impedance by placing a voltage application / voltage measurement electrode in the trunk umbilical cord (See Patent Document 1 and Patent Document 2).

Japanese Patent No. 3396677 Japanese Patent No. 3396684

  However, information on body adipose tissue is particularly useful for screening lifestyle-related diseases such as diabetes, hypertension and hyperlipidemia, and in particular, visceral fat that has adhered and accumulated in the vicinity of internal organ tissues. For organizations, the importance of measurement is increasing day by day.

  Visceral adipose tissue is an adipose tissue that is intensively distributed near the abdomen of the trunk, and has been determined by the cross-sectional area of the adipose tissue in an abdominal cross-sectional image obtained by X-ray CТ or MRI. However, the apparatus is large, and in the case of X-rays, there is a problem of exposure, and there is a cost aspect, which is not suitable for measurement in the field and home. Therefore, the visceral adipose tissue is generally estimated from the correlation with the whole body adipose tissue or the correlation with the whole body lean tissue, and sufficient reliability has not been ensured even for screening.

  Recently, a method for estimating visceral adipose tissue information by placing electrodes around the umbilical girth of the trunk and measuring the internal impedance of the trunk is also under development. However, this method is based on the existence of a significant correlation among the skeletal muscle tissue layer, the subcutaneous fat tissue layer, and the visceral adipose tissue. If information of any tissue (layer) can be captured, it is approximate. It is assumed that information can be estimated. For this reason, good results can be expected for healthy subjects with high independence where a very significant correlation can exist, but subjects with different correlations between tissues, such as visceral adipose tissue, are significantly enlarged. In addition, the measurement result in the subject having a remarkably low correlation with the subcutaneous fat tissue layer or the skeletal muscle tissue layer can include a large error. In other words, even if this method is under development, if it is a subject who can live a healthy independent life, it is possible to measure somehow regardless of where the electrodes are placed around the entire umbilicus. In particular, the problem is large when measurement is performed on a bedridden patient on a bed.

  In addition, this method under development can be said to be a high technology in that the impedance value related to the internal tissue is obtained by applying current from the abdominal surface to the tissue site to be measured. The fact is that the measured impedance information itself has little useful sensitivity to visceral adipose tissue due to problems in the internal structure of the trunk, which is the part. That is, the trunk that is the measurement site is short and thick, the multiple structure, that is, the visceral fat tissue that is the measurement target is covered with a skeletal muscle tissue layer that exhibits very good conductivity together with the internal organ tissue and the spine tissue, This skeletal muscle tissue layer has a structure in which it is covered with a subcutaneous fat tissue layer having very poor conductivity. In particular, the visceral adipose tissue that is the subject of measurement is dominated by internal organ tissues that are less conductive than the skeletal muscle tissue layer and visceral adipose tissues that are attached and accumulated on this internal organ tissue and have poor conductivity. Due to the configuration, the internal conductivity is considerably inferior to that of the skeletal muscle tissue layer. For this reason, even if the current application electrode is simply arranged around the abdomen, the majority is energized through the skeletal muscle tissue layer, and the current density distribution is also a potential distribution dominant to the skeletal muscle tissue layer from the voltage measurement electrode. Will be observed. Furthermore, the distribution of the applied current density is determined by the surface area of the electrode to which the current is applied or the electrode width in the abdominal circumference direction, and the current density in the subcutaneous fat tissue layer immediately below the electrode is widened, and the observation of information in the resistance region becomes dominant. End up.

  Furthermore, because the trunk, which is the measurement site, is thick and short, the sensitivity in the subcutaneous adipose tissue layer in the current density concentration (spreading resistance) region directly under the current application electrode is higher, and the skeletal muscle tissue layer is more in comparison with the adipose tissue. Since the electrical conductivity is considerably high, a route in which most of the current passing through the subcutaneous adipose tissue layer returns through the subcutaneous adipose tissue layer to the side of the current application electrode through the skeletal muscle tissue layer is taken. In addition, the internal current distribution is greatly distorted in this skeletal muscle tissue layer. Therefore, in the conventional method, most of the measured potential is information of the subcutaneous fat tissue layer, and the visceral adipose tissue to be measured, that is, the visceral adipose tissue that adheres to and accumulates in the internal organ tissue and its surroundings. It is almost impossible to energize the battery, and only information with extremely low measurement sensitivity of 10% or less of the entire impedance measurement section can be captured.

  In order to avoid these problems, a method for preventing an increase in the estimation error by incorporating an abdominal circumference that is highly correlated with the area of the subcutaneous fat tissue layer into the estimation formula has been considered. It is nothing but indirect estimation based on the correlation between the constituent tissues, and it is difficult to say that it is a measurement method that secures the necessary energization sensitivity at the center of the abdomen. In other words, individual errors that deviate from the statistical correlation design cannot be guaranteed, especially when there are many pathologically subcutaneous or visceral adipose tissues, or when there are many / small intermediate skeletal muscle tissue layers. obtain. It should be noted that the area of the subcutaneous fat tissue layer is highly correlated with the abdominal circumference, because the human trunk has a concentric tissue arrangement design, and the subcutaneous fat tissue layer is the outermost arrangement, so the outer circumference This is because the area is determined by the length and the thickness of the subcutaneous fat tissue.

  Usually, the four-electrode method is also used for the electrode arrangement on the trunk. In this method, a current is applied to the body of the subject, and a potential difference generated in the measurement region of the subject by the applied current is measured to measure the bioelectrical impedance of the measurement region. When the four-electrode method is applied to a thick and short measurement site section such as the trunk, the current density concentration at the beginning of current spreading (ie, spreading resistance region) is, for example, near the subcutaneous fat tissue layer directly under the current application electrode. A large potential difference is generated, and this potential difference occupies most of the potential difference measured between the voltage measurement electrodes. In order to reduce the influence of the spreading resistance, it is important to arrange the current application electrode and the voltage measurement electrode with a sufficient distance. Since general measurement is performed under the condition that the measurement interval is long and the distance between the voltage measurement electrodes can be sufficiently secured, so-called S / N sensitivity (N is an influence (noise) due to spreading resistance, and S is between the voltage measurement electrodes). The signal to be measured) should be sufficiently secured. However, in the case of a thick and short measurement site such as the trunk, if the voltage measurement electrode is moved away from the current application electrode in order to reduce N, the voltage measurement electrode section distance becomes smaller. As a result, S becomes smaller and eventually the S / N becomes worse. Further, the spreading resistance portion having a high current density is a subcutaneous fat tissue layer, and a thick and obese subject is generally used. Therefore, the N is considerably large, and the S / N is doubled. End up. As described above, when the four-electrode method is used for a short and short measurement site such as the trunk, a useful S / N sensitivity to visceral adipose tissue can be obtained simply by placing an electrode on the circumference of the umbilicus. It is speculated that it is quite impossible to secure. The S / N will be described in more detail in the description of the embodiments described later.

  An object of the present invention is to eliminate these problems in the prior art, ensuring sensitivity necessary for measurement even in a complex tissue region of internal organ tissue and visceral adipose tissue with poor electrical conductivity and accumulated in the trunk. In addition to making it possible to accurately and easily measure information on visceral adipose tissue that adheres and accumulates around internal organ tissue and subcutaneous adipose tissue layer that accumulates in the subcutaneous layer, it is a complex mixed tissue It is an object to provide a trunk visceral fat measurement method and apparatus capable of providing measurement result information with high measurement reproducibility and high reliability, and a health guideline advice apparatus using the measurement information. In particular, an object of the present invention is to ensure measurement sensitivity to visceral adipose tissue volume, or to secure optimum S / N conditions as a four-electrode method.

  According to one aspect of the present invention, the trunk visceral fat is obtained by utilizing the bioimpedance of the trunk measured using the trunk or the current application electrode pair and the voltage measurement electrode pair disposed on the trunk and the extremities. In the trunk visceral fat measurement method for obtaining a tissue amount, the internal organ tissue and the visceral fat tissue inside the trunk are energized by disposing one current application electrode of the current application electrode pair at the umbilical position. A method for measuring trunk visceral fat is provided.

  According to one embodiment of the present invention, it is preferable that at least a part of the one current applying electrode is inserted into the umbilical recess. According to another embodiment of the present invention, it is preferable that at least a part of the one current application electrode is in close contact with the concave portion of the navel.

  According to another embodiment of the present invention, it is preferable that the other current application electrode of the current application electrode pair is disposed in the spine position. According to still another embodiment of the present invention, it is preferable that the other current applying electrode is disposed on the spine umbilical circumference or on the waist part slightly below the spine umbilical circumference.

  According to still another embodiment of the present invention, one voltage measurement electrode of the voltage measurement electrode pair is arranged near the umbilical position, and the other voltage measurement electrode is affected by spreading resistance due to the other current application electrode. It is preferable to secure a distance that can avoid the above-mentioned problem, and to place it slightly above the circumference of the umbilical cord or the spine umbilical field from the position of the other current application electrode in the trunk longitudinal direction.

  According to still another embodiment of the present invention, the other current application electrode of the current application electrode pair may be arranged on the limb. According to still another embodiment of the present invention, the other current application electrode is disposed on either the left or right upper limb, and one voltage measurement electrode of the voltage measurement electrode pair is disposed near the umbilical position, The other voltage measurement electrode of the voltage measurement electrode pair may be arranged on the other of the left and right upper limbs.

  According to still another embodiment of the present invention, the other current applying electrode is disposed on either the left or right lower limb, the one voltage measuring electrode of the voltage measuring electrode pair is disposed near the umbilical position, The other voltage measurement electrode of the voltage measurement electrode pair may be arranged on the other of the left and right lower limbs.

  According to still another embodiment of the present invention, a trunk skeletal muscle tissue amount is obtained based on body specifying information, and a trunk skeleton is obtained based on the obtained trunk skeletal muscle tissue amount and body specifying information. The impedance of the muscle tissue layer is obtained, the internal organ tissue amount of the trunk is obtained based on the body specifying information, and the internal organ tissue of the trunk is obtained based on the obtained internal organ tissue amount and the body specifying information of the trunk The impedance of the trunk visceral adipose tissue was determined based on the bioimpedance of the trunk, the impedance of the trunk skeletal muscle tissue layer and the impedance of the internal organ tissue of the trunk, and the obtained impedance The amount of trunk visceral adipose tissue may be obtained based on the impedance of trunk visceral adipose tissue and body specifying information. According to still another embodiment of the present invention, the trunk visceral fat is based on the bioelectrical impedance of the trunk and the determined impedance of the trunk skeletal muscle tissue layer and the impedance of the internal organ tissue of the trunk. The step of obtaining the impedance of the tissue is such that an electrical equivalent circuit of the trunk is connected to a serial circuit of the impedance of the internal organ tissue of the trunk and the impedance of the trunk visceral fat tissue of the trunk skeletal muscle tissue layer. The impedance may be connected in parallel.

  According to another aspect of the present invention, the trunk visceral fat using the trunk or the bioimpedance of the trunk measured using the current application electrode pair and the voltage measurement electrode pair arranged on the trunk and the extremities In a trunk visceral fat measuring device for obtaining a tissue mass, a trunk visceral fat measuring device characterized in that one current applying electrode of the current applying electrode pair is arranged at the umbilical position.

  According to one embodiment of the present invention, it is preferable that the one current applying electrode has a shape extending so as to be inserted into the umbilical recess. According to another embodiment of the present invention, it is preferable that the one current applying electrode has a portion that can be in close contact with the concave portion of the navel.

  According to another embodiment of the present invention, it is preferable that the other current application electrode of the current application electrode pair is arranged in a spine position. According to still another embodiment of the present invention, it is preferable that the other current application electrode is arranged on the spine umbilical circumference or a lumbar portion slightly below the spine umbilical circumference.

  According to still another embodiment of the present invention, one voltage measurement electrode of the voltage measurement electrode pair is arranged in the vicinity of the umbilical position, and the other voltage measurement electrode is affected by spreading resistance due to the other current application electrode. It is also possible to secure a distance that can avoid the above-mentioned problem, and to arrange it slightly above the umbilical circumference or the spine umbilical circumference in the longitudinal direction of the trunk from the position of the other current application electrode.

  According to still another embodiment of the present invention, the other current application electrode of the current application electrode pair may be arranged on the limb. According to still another embodiment of the present invention, the other current application electrode is disposed on one of the left and right upper limbs, and one voltage measurement electrode of the voltage measurement electrode pair is disposed near the umbilical position, The other voltage measurement electrode of the voltage measurement electrode pair may be disposed on the other of the left and right upper limbs.

  According to still another embodiment of the present invention, the other current application electrode is disposed on one of the left and right lower limbs, and one voltage measurement electrode of the voltage measurement electrode pair is disposed near the umbilical position, The other voltage measurement electrode of the voltage measurement electrode pair may be arranged on the other of the left and right lower limbs.

  According to still another embodiment of the present invention, the trunk bioimpedance measuring means for measuring the bioimpedance of the trunk and the trunk skeletal muscle tissue amount are estimated based on the body specifying information, and the estimated Trunk skeletal muscle tissue layer impedance estimation means for estimating the impedance of the trunk skeletal muscle tissue layer based on the trunk skeletal muscle tissue amount and body specific information, and internal organ tissue of the trunk based on the body specific information An internal organ tissue impedance estimation means for estimating the impedance of the internal organ tissue of the trunk based on the estimated internal organ tissue amount of the trunk and the body specifying information; Trunk visceral fat group for estimating impedance of trunk visceral adipose tissue based on impedance, impedance of trunk skeletal muscle tissue layer and impedance of internal organ tissue of trunk It is also possible to further comprise woven impedance estimation means and trunk visceral fat tissue amount estimation means for estimating the trunk visceral fat tissue amount based on the estimated trunk visceral fat tissue impedance and body specifying information. . According to still another embodiment of the present invention, the trunk visceral adipose tissue impedance estimation means includes: an electrical equivalent circuit of the trunk; the impedance of the internal organ tissue of the trunk and the trunk visceral adipose tissue It may be estimated that the impedance of the trunk skeletal muscle tissue layer is connected in parallel to a series circuit with the impedance of the trunk.

  According to the present invention, by placing one current application electrode of the current application electrode pair in the umbilical position and arranging the other current application electrode in the spine position or in the four limbs (upper limb or lower limb), the subcutaneous fat tissue layer is formed. Current can be applied to the internal organ tissue and visceral adipose tissue by energizing between the umbilical recess and spine, or the extremities (upper limbs or lower limbs), which are almost nonexistent. It is possible to measure predominantly the information of the composite tissue layer in which the visceral fat tissue and the visceral fat tissue are mixed.

  Therefore, according to the present invention, when measuring visceral adipose tissue information inside the umbilical position circumferential position, the arrangement of the current application electrode pair is between the umbilical position and the spine position, or between the limbs (upper limbs or lower limbs), Because it is between the umbilical position and the lower lumbar region from the back umbilical circumference, energize between the umbilical recess and the spine or the extremities (upper limbs or lower limbs), and internal organ tissue near the umbilical position And stable diffusion energization to the composite tissue layer of visceral adipose tissue becomes possible. The back side energized electrode position is the lower waist slightly from the circumference of the umbilical cord, so that the aponeurosis with few skeletal muscle tissue layers is dominant, and the subcutaneous fat tissue layer is very thin along the spinal column Therefore, it is expected that the current diffused in the rectus abdominis muscle tissue layer will be concentrated on the circumference of the umbilicus by energization from the extremities (upper limbs or lower limbs) and the effect of reducing the effect of spreading resistance of the subcutaneous fat tissue layer it can.

  According to the present invention, it is possible to measure visceral adipose tissue information with high reliability, and in addition to visceral adipose tissue information, information on the subcutaneous adipose tissue layer can be simultaneously measured by abdominal circumference information or a separate measurement electrode arrangement. Improvement in the accuracy of relative information such as / S (visceral fat tissue volume / subcutaneous fat tissue volume) can be expected.

  In addition, the energization amount and sensitivity to the composite tissue layer of the internal organ tissue and visceral adipose tissue can be increased, and the N component due to potential disturbance due to the skeletal muscle tissue layer that becomes noise also causes the rectus abdominis muscle tissue layer to be a virtual electrode Therefore, the S / N can be improved.

  Furthermore, since the subject can be aware of the measurement site by attaching the electrode to the abdomen, it is beneficial for improving measurement accuracy and ensuring motivation by conscious restraint.

  Furthermore, it is possible to reveal highly accurate screening information according to the required level while following the combination with the conventional simple measurement method and the simplicity of the visceral adipose tissue accumulation and visceral adipose tissue accumulation. .

  Furthermore, according to the present invention, it can be easily measured by a small and inexpensive device, so that it can be optimized for home use. In addition, as information that can contribute to the maintenance of motivation for appropriate diet and exercise daily diet, the development and development of skeletal muscles in each segment of the limb trunk by combining adipose tissue adhesion and accumulation with known induction methods Because the change of the healthy body design by the present condition of quantity and balance and exercise and diet diet can be obtained, the self-management of health maintenance and promotion can be continued. In other words, not only digitizing the visceral adipose tissue accumulation as a result of integrating my lifestyle, but also expressing my body skeletal muscle tissue layer balance etc. with numerical values and schematic diagrams, improving self-recognition, The initial motivation can be enhanced, and the change in the results of the initial effort in diet etc. is reflected in the minute change in the highly sensitive part of the skeletal muscle tissue layer, so that the motivation can be maintained continuously. Can contribute.

  Furthermore, by improving the reliability of the measurement impedance of the trunk abdomen, not only the measurement accuracy is improved, but also abdominal condition check before measurement is possible, in addition to screening in terms of visceral adipose tissue estimation accuracy, It can be applied to screening by early check of inflammation in internal organ tissues and pathological abnormal fluid distribution.

  Furthermore, the possibility of misplacement of the electrodes can be eliminated by arranging the current application electrodes directly on the umbilical position and the position of the spine or the extremities (upper limbs or lower limbs). An improvement in accuracy can also be expected.

  Before describing the embodiments and examples of the present invention in detail, the principle of measuring visceral adipose tissue of the trunk according to the present invention will be described. The present invention basically uses the bioelectrical impedance information and the body specifying information, and visceral fat tissue information (cross-sectional area amount, volume amount or weight) of the trunk (trunk abdomen), more specifically, the body The present invention relates to a method for enabling easy measurement of adipose tissue accumulated in a trunk, particularly visceral adipose tissue adhering and accumulating around an internal organ tissue with high accuracy.

For this reason, the present invention makes full use of the following technique.
(1) The tissue information included in the bioelectrical impedance information of the trunk is assumed to be an equivalent circuit model in which the skeletal muscle tissue layer, the internal organ tissue, and the visceral fat tissue are serially parallel. Here, the internal organ tissue and the visceral adipose tissue are considered in series (therefore, a change in energization amount can be expected depending on the size of the visceral adipose tissue).

(2) When the abdominal circumference can be secured as body specific information, the subcutaneous fat tissue layer, the skeletal muscle tissue layer, the internal organ tissue, and the visceral fat are included as a high-accuracy model including the subcutaneous fat tissue amount in the equivalent circuit model. Assuming a series-parallel equivalent circuit model in the organization.

(3) Subcutaneous adipose tissue mass estimation is made up of multiple regression equations with the abdominal circumference in the body specifying information as the main explanatory variable. Furthermore, put the square of the abdominal circumference as the main explanatory variable.

(4) The determination of internal organ tissue information is made up of multiple regression equations with height information as the main explanatory variable in the body specific information, and is used to determine uncertain information for visceral fat tissue information estimation. .

(5) The standard measurement of the tissue used for the multiple regression analysis (calibration curve creation method) for quantifying each tissue is the tissue cross-sectional area (CSA) from the X-ray CT tomographic image at the umbilical position or the CSA by the MRI method. Tissue volume and weight using the DEXA method and MRI method (integration processing for each slice in the length direction) for the entire trunk can be calculated from the tissue density information from previous studies. ). In the DEXA method, the total adipose tissue information of the total of the abdominal visceral adipose tissue and the subcutaneous adipose tissue layer can be measured as a reference.

(6) In order to be able to capture visceral adipose tissue information with high accuracy using the method as described above, it is necessary to take a means to replace fluctuations in the measured impedance information of the trunk due to breathing or the like with a certain condition value. The impedance measurement sampling period is within 1/2 of the general respiratory cycle, the respiratory change is monitored in time series, the maximum value and the minimum value for each respiratory cycle are determined for each respiratory cycle, Capability to capture median rest breathing.

(7) Further, it is also possible to check in advance of adverse effects due to eating and drinking before the measurement and retention of bladder and urine from the measured impedance information. Generally, the information on the skeletal muscle tissue layer is dominantly reflected in the impedance value of the trunk in a general healthy subject group. In addition, information on the skeletal muscle tissue layer of the trunk is very small as a measurement value, and no great difference is recognized between individuals. The reason is that the design is highly correlated with anti-gravity muscles that support and develop their own weight under the gravity of the earth, so subjects who are specially bedridden and not affected by gravity, or athletes who are subject to several times the stress of their own weight This is because it is almost determined by the body size except for special groups. Here, the influence on the impedance of the trunk other than the skeletal muscle tissue layer and the respiratory fluctuation is an adverse effect due to food and drink and urinary bladder urine storage. Therefore, when the impedance values of the trunk are collected as collective data and viewed as the mean value [mean] and deviation [SD], it can be seen that the effects of food and drink and bladder urine retention are in the range exceeding 2SD. It was. However, considering even a semi-general group such as athletes to a certain extent, 3SD can be used as a criterion to screen for this effect.

  Next, the measurement principle of the present invention based on the above-described method will be described in further detail.

1. Electrical equivalent circuit modeling of trunk tissue (1) The trunk mainly consists of subcutaneous fat tissue layer, skeletal muscle tissue layer (abdominal muscle group, back muscle group), internal organ tissue and visceral fat attached to the gap It can be thought of as an organization. The reason why the bone tissue is not listed as a constituent tissue is that the bone tissue has a very high quantitative correlation with the skeletal muscle tissue layer and can be considered as an integral tissue body. The volume resistivity is considered to have a property that is considerably good in conductivity by including bone marrow tissue and the like in a living body, and has characteristics close to those of a skeletal muscle tissue layer and internal organ tissue. Therefore, when these four tissues are represented by an electrical equivalent circuit model, the internal organ tissue and the visceral adipose tissue are configured in series, and the subcutaneous adipose tissue layer and the skeletal muscle tissue layer are respectively formed with respect to the serial composite tissue layer. Configured in parallel. This equivalent circuit model will be described in detail in the description of FIGS.

  According to this model, a current flows predominantly through the skeletal muscle tissue layer when energized in the length direction of the trunk. Since visceral adipose tissue adheres to the gaps around the internal organ tissue, when there is no visceral adipose tissue or when there is little visceral tissue, the internal organ tissue exhibits conductivity close to that of the skeletal muscle tissue layer. Also, a current is applied. Further, as the visceral adipose tissue increases, the energization amount to the composite tissue layer as a complex of the internal organ tissue and the visceral adipose tissue decreases. The model impedance when the measured impedance of the trunk and the four tissues constituting it are expressed by an equivalent circuit model can be expressed as follows.

Ztm = ZFS // ZMM // (ZVM + ZFV) Equation 1
here,
Impedance of the whole trunk: Ztm
Impedance of subcutaneous adipose tissue layer: ZFS: Volume resistivity is large.
Impedance of skeletal muscle tissue layer: ZMM: Volume resistivity is small.
Impedance of internal organ tissue: ZVM ... It is considered as volume resistivity close to the skeletal muscle tissue layer.
Impedance of visceral adipose tissue: ZFV: Volume resistivity is considered to be equal to or slightly smaller than the subcutaneous adipose tissue layer. Since the synthetic decomposition of adipose tissue is faster than that of the subcutaneous adipose tissue layer, it is considered that the blood vessels and blood volume in the tissue are large.

The electrical characteristics between tissues are determined by volume resistivity ρ [Ωm] rather than impedance. From the above relationship, the electrical characteristic values of each tissue are generally explained by the following relationship.
ρMM << ρ (VM + FV) << ρFS
ρVM << ρFV
ρMM = ρVM or ρMM <ρVM
ρFV = ρFS or ρFV <FS
here,
Volume resistivity of subcutaneous adipose tissue layer: ρFS
Volume resistivity of composite tissue layer of internal organ tissue and visceral adipose tissue inside skeletal muscle tissue layer: ρ (VM + FV)
Volume resistivity of skeletal muscle tissue layer: ρMM
Therefore, due to the relationship with Equation 1, the electrical property comparison relationship between the tissues is
ZFS >> (ZVM + ZFV) >> ZMM ... Formula 2
It becomes.

(2) By simply placing an electrode on the circumference of the abdominal umbilicus using the conventional method, the impedance component of the subcutaneous fat tissue layer becomes the dominant measurement due to the effect of spreading resistance directly under the current application electrode, Separation and removal of the subcutaneous adipose tissue layer by the ideal four-electrode method could not be realized. That is,
Ztm = 2 * ZFS + ZMM2 // (ZVM + ZFV) ・ ・ ・ Equation 3
According to the present invention, an ideal four-electrode method can be realized by applying the new electrode arrangement method, and the impedance component of the subcutaneous fat tissue layer can be deleted.
As will be described later, according to the electrode arrangement method of the present invention, electricity is applied between the umbilical recess and the spine. Therefore, the electrical equivalent circuit model is easy to spread by disposing the voltage measurement electrode apart from the current application electrode because the ZFS in FIGS. The influence of resistance can be avoided. That is, Equation 3 is expressed as follows.
Ztm = ZMM // (ZVM + ZFV) Equation 4

2. Estimating trunk skeletal muscle tissue cross-sectional area [AMM] and trunk skeletal muscle tissue layer impedance [ZMM] (3) Since skeletal muscle tissue volume is highly correlated with cross-sectional area volume and volume, here we Think by area. The cross sectional area amount AMM of the skeletal muscle tissue layer of the trunk abdomen can be roughly estimated by the body specifying information. The reason is that the developmental design of the body's skeletal muscle tissue layer is almost determined by the development and adaptation to support its own weight under the gravity of the earth. Therefore, it can be estimated with the body specifying information except for athletes and non-gravity adaptors such as paralyzed patients and caregivers. This estimation is performed by substituting height H, weight W, and age Age into the following equations.
AMM = a * H + b * W + c * Age + d Equation 5
Here, a, b, c, and d are constants that give different values for men and women.

(4) The trunk skeletal muscle tissue layer impedance [ZMM] can be expressed by the following equation using the trunk skeletal muscle tissue cross-sectional area amount [AMM].
ZMM = a0 * H / AMM + b0 Equation 6
Here, a0 and b0 are constants.

3. Estimating internal organ tissue volume [AVM] and internal organ tissue impedance [ZVM] (5) Estimating internal organ tissue volume [VM] of the trunk from body (individual) specific information such as height, weight, sex, and age I can do it. Among the explanatory variables, the influence of the height term is large.
Internal organ tissue volume [AVM] = a1 * Height [H] + b1 * Weight [W] + c1 * Age [Age] + d1 Equation 7
Here, a1, b1, c1, and d1 are constants that give different values for men and women.

(6) Next, the impedance ZVM of the internal organ tissue is estimated.
The internal organ tissue impedance ZVM can be estimated from body (individual) specifying information such as height, weight, sex, and age. Among the explanatory variables, the influence of the height term is large. For convenience, the internal organ tissue amount AVM obtained above is used here. This estimation can be performed using the following equation.
ZVM = a2 * H / AVM + b2 Equation 8
Here, a2 and b2 are constants.

4). Estimation of visceral adipose tissue impedance [ZFV] and visceral adipose tissue volume [AFV] (7) Next, the impedance ZFV of the visceral adipose tissue is estimated.
When Equation 4 is transformed,
1 / Ztm = 1 / ZMM + 1 / (ZVM + ZFV) (9)
When ZFV is derived from Equation 9, the following is obtained, and impedance information having information on visceral adipose tissue can be obtained.
ZFV = 1 / [1 / Ztm-1 / ZMM]-ZVM ... Equation 10
In this equation, Ztm is an actual measurement value. Further, since the trunk skeletal muscle tissue layer impedance ZMM and the internal organ tissue impedance ZVM can be estimated from the body specifying information as described above, ZFV can be extracted by substituting the estimated values. That is, it can be calculated by substituting Equation 6 and Equation 8 into Equation 10.

(8) Visceral adipose tissue volume AFV is treated here as the cross-sectional area of visceral adipose tissue. Visceral adipose tissue amount AFV can be calculated from the above impedance information and height information,
AFV = aa * H / ZFV + bb ... Formula 11
Here, aa and bb are constants.

5. Estimation of subcutaneous fat tissue volume [AFS] (9) The subcutaneous fat tissue volume AFS of the trunk can be estimated from impedance information ZFS of the subcutaneous fat tissue layer and abdominal circumference Lw.
Subcutaneous fat tissue volume [AFS] = aa0 * ZFS * Lw + bb0
Here, aa0 and bb0 are constants.

6). Estimating the trunk visceral fat / subcutaneous fat ratio [V / S] (10) The visceral fat / subcutaneous fat ratio [V / S] is calculated based on the amount of subcutaneous fat tissue [AFS] from Equation 12 and the visceral fat tissue from Equation 11 It can be obtained from the quantity [AFV].
V / S = AFV / AFS Equation 13

7). Concept of internal organ tissue abnormality judgment by trunk (middle) impedance (11) Trunk impedance Ztm necessary for visceral adipose tissue mass estimation is a part that fluctuates greatly due to breathing and eating and drinking, stability and Measurement of highly reliable information is required. Therefore, highly reliable impedance information of the trunk can be secured by applying the following processing. In addition, it is possible to determine a tissue abnormality of the trunk from the viewpoint as information related to the disturbance of the body fluid distribution of the trunk.

(12) Removal of influence of fluctuation due to respiration (a) The impedance of the trunk is measured at a sampling cycle shorter than 1/2 of a general respiration cycle time.
(B) A smoothing process such as moving average is performed on the measurement data for each sampling.
(C) From the time series data after processing, the periodicity of respiration and the maximum and minimum values for each cycle are detected.
(D) A maximum value and a minimum value for each period are averaged separately.
(E) The average value of the maximum value and the minimum value is averaged, and the median value of respiration is calculated.
(F) When the median respiration for each respiratory cycle enters a stable range within the specified number of times, it is determined that the median respiration is confirmed, and the determined impedance value is registered as the impedance value of the trunk. And complete the measurement.

(13) Abnormal value determination processing due to eating and drinking and water retention (such as urine) in the bladder (a) As for the impedance of the trunk, 26.7 ± 4.8Ω (mean ± SD) is a general value of the group.
(B) On the other hand, the value at the time of constipation and urinary bladder retention and fullness of food and drink in the stomach exceeds the range of mean ± 3SD.
(C) Therefore, when a measured value exceeding 3SD is obtained, the subject is informed of the possibility of effects such as eating and drinking and bladder and urine, and is encouraged to hope for the measurement in the best environment. However, in a subject whose skeletal muscle tissue layer development and internal organ tissue are different from the standard size without actually having these effects, proceed so that the measurement can be continued.
(D) Further, as a method for increasing the measurement sensitivity, the specified values are subdivided according to sex, weight, and height. Alternatively, the specified value is defined as a unit-specific value divided by weight or divided by height.

  Next, based on the measurement principle of the present invention as described above, an embodiment of a trunk visceral fat measurement method and apparatus according to the present invention and a health guide advice device using measurement information will be described.

  FIG. 1 is a schematic perspective view showing an appearance of an embodiment of a trunk visceral fat measuring device according to the present invention, FIG. 2 is a method for using the trunk visceral fat measuring device according to the present invention, and FIG. FIGS. 4A and 4B are a schematic perspective view and a cross-sectional view showing an external appearance of an embodiment of a current applying electrode disposed at a position, and FIG. 4 is a block diagram of a main body part included in a trunk visceral fat measuring device according to the present invention.

  As shown in FIG. 1, the trunk visceral fat measuring device 1 of the present invention is connected to a main body part 11, a grip electrode part 130 directly connected to the main body part 11, and a main body part 11 via a band 120. And a grip electrode portion 140.

  As shown in FIG. 2, the grip electrode portions 130 and 140 are used by holding the grip electrode portions 130 and 140 in each hand and pressing them on the measurement site of the subject, that is, the umbilical position and the spine position, respectively. The current application electrode 13A and the voltage measurement electrode 14A are provided on the contact surface of the umbilical cord side grip electrode part 130, and the current application electrode 13B and the voltage measurement electrode 14B are provided on the contact surface of the spine position side grip electrode part 140. It is done. For example, the current application electrodes 13A and 13B are provided outside the contact surface of the grip electrode part 130 and outside the contact surface of the grip electrode part 140, and the voltage measurement electrodes 14A and 14B are inside the contact surface of the grip electrode part 130. And on the inner side of the contact surface of the grip electrode part 140. In addition, the arrangement | positioning and number of electrodes are determined according to a use aspect, and are not specifically limited.

  The current application electrodes 13A and 13B and the voltage measurement electrodes 14A and 14B may be realized by performing metal plating on the surface of the SUS material and the resin material. This type of electrode is used by coating a water-retaining polymer film on the surface of a metal electrode to wipe off moisture before measurement or wet it with water. By soaking in water, the stability of the electrical contact with the skin can be ensured.

  Further, although not particularly shown, it is possible to use an adhesive-attached electrode. This is a type in which a replaceable adhesive pad is attached to the base electrode surface of each electrode to ensure contact stability with the skin. This type is often used in, for example, low-frequency treatment devices and electrocardiogram electrodes, etc., and a disposable form that is removed and discarded after measurement, and the pad surface is dirty, resulting in decreased adhesion and moisture evaporation In some cases, the waste is replaced only when it is stored, and is stored in a cover sheet or the like until it is discarded.

  As shown in FIG. 3, the current application electrode 13 </ b> A provided on the contact surface of the umbilical-position-side grip electrode portion 130 extends so as to be inserted into the umbilical recess, for example, like a truncated cone protruding from a disk-shaped portion. It has a convex shape part. And the side part and top part of this convex-shaped part can be closely_contact | adhered to the recessed part of a navel. The current application electrode 13A having such a shape is produced, for example, by processing a sheet-like disposable electrode into a three-dimensional structure having both a bellows structure and an emboss structure as shown in the AA cross-sectional view of FIG. be able to. More specifically, after embossing a resin-based base sheet material before applying a conductive coating such as metal plating, concentric folding is applied, and the embossed part except the bellows part is electrically conductive. By providing the adhesive portion having the property (and water retention), it is possible to realize the current application electrode 13A having a three-dimensional electrode structure that fits into the umbilical recess. In addition, it is desirable to adopt a soft electrode that does not cause pain or damage when the current application electrode 13A is pressed against the umbilical position by using silicone rubber or the like as a material constituting the base material.

On the front surface of the main body 11, an operation display panel 5 having an operation unit 51 and a display unit 52, an alarm buzzer 22, and the like are provided. As is apparent from FIG. A control unit 21, a power supply unit 18, a storage unit (memory) 4, an impedance measurement unit, and the like are provided. The operation unit 51 can be used for inputting body specifying information including height, weight, and the like, and the operation display panel 5 displays various results, advice information, and the like through the display unit 52. The operation display panel 5 may be formed as a touch panel type liquid crystal display in which the operation unit 51 and the display unit 52 are integrated.
The calculation / control unit 21 calculates the trunk skeletal muscle tissue cross-sectional area based on the body specifying information (height, weight, etc.) input from the operation unit 51, the measured impedance, and the expressions 1 to 13. Calculating trunk skeletal muscle tissue layer impedance, visceral fat tissue impedance, visceral fat tissue mass, internal organ tissue mass, internal organ tissue impedance, subcutaneous fat tissue mass, trunk visceral fat / subcutaneous fat ratio, etc. It performs processing such as fluctuation removal processing, subcutaneous fat tissue layer impedance, internal organ tissue abnormality determination, and other various input / output, measurement, calculation, and the like. The power supply unit 18 supplies power to each part of the electrical system of the present apparatus. The storage unit 4 stores body specifying information such as height, trunk length, trunk manager, etc., the above formulas 1 to 13, and the like, as well as appropriate messages for health guide advice as described later. Remember.

The impedance measurement unit includes a plurality of current application electrodes 13 for applying current to the measurement site of the subject, a plurality of voltage measurement electrodes 14 for measuring a potential difference at the measurement site of the subject, and a current for supplying current to the current application electrode 13. A source 12, a current application electrode selection unit 20a for selecting an arbitrary electrode from a plurality of current application electrodes 13, a voltage measurement electrode selection unit 20b for selecting an arbitrary electrode from a plurality of voltage measurement electrodes 14, and a voltage A differential amplifier 23 that amplifies the potential difference measured by the measurement electrode 14, a bandpass filter (BPF) 24 for filtering, a detection unit 25, an amplifier 26, an A / D converter 27, and the like are included. The current application electrode selection unit 20 a is connected between the current application electrode 13 and the current source 12. The voltage measurement electrode selector 20 b is connected between the voltage measurement electrode 14 and the differential amplifier 23.
In FIG. 4, only two current application electrodes 13 and two voltage measurement electrodes 14 are shown. However, when the subcutaneous fat tissue layer impedance is separately measured, it is necessary to provide three or more (omitted here). .

  In order to explain the principle of the present invention, an electrical equivalent circuit model is introduced. FIG. 5 is a diagram schematically showing the structure of the trunk abdomen that is the basis of this equivalent circuit. From the viewpoint of electrical characteristics, the trunk is composed of subcutaneous fat tissue layer (FS), skeletal muscle tissue layer (MM), internal organ tissue (VM), and visceral adipose tissue (FV) adhering to the gap. Can be divided into

  As described above, in the conventional method, the trunk, which is the measurement site, is short and thick, and the sensitivity in the subcutaneous fat tissue layer in the current density concentration (spreading resistance) region directly under the current application electrode is increased, and the skeletal muscle tissue layer is Since the conductivity is considerably higher than that of adipose tissue, a route in which most of the current that has passed through the subcutaneous adipose tissue layer returns through the subcutaneous adipose tissue layer to the side of the current application electrode that opposes the skeletal muscle tissue layer. As a result, the internal potential distribution is greatly distorted in this skeletal muscle tissue layer, and most of the measured potential becomes information on the subcutaneous fat tissue layer, and the visceral fat to be measured is The tissue, that is, the internal organ tissue and the visceral adipose tissue that adheres to and accumulates in the surrounding area, can hardly be expected to be energized, and only 10% or less of the entire impedance measurement section could capture information with extremely low measurement sensitivity. (FIG. 6A Irradiation).

  In the present invention, by adopting a dedicated current application electrode having a shape matched to the umbilical recess, it is possible to energize between the umbilical recess and the spine where there is almost no subcutaneous fat tissue layer. Energization of the composite tissue layer of organ tissue and visceral adipose tissue can be expected (see FIG. 6B).

  FIG. 7 is a diagram in which the schematic diagram of the trunk shown in FIG. 5 is modeled by the abdominal circumference cross section at the umbilical height. As shown in this figure, the trunk cross section includes the outermost subcutaneous adipose tissue layer (FS), the skeletal muscle tissue layer (MM) just inside, and the inner organ tissue (VM) inside. It includes visceral adipose tissue (FV) surrounding it.

  FIG. 8 shows the schematic diagram shown in FIG. 7 as an electrical equivalent circuit. Here, as an example, current (I) is applied by the current application electrode 13 in the vicinity of the front and back of the navel, and the potential difference (V) is measured by the voltage measurement electrode 14 disposed in the vicinity thereof. In the case of an equivalent circuit, the electrical resistance is mainly determined by the impedance of the subcutaneous fat tissue layers around the umbilicus (ZFS1, ZFS2), the impedance of the subcutaneous fat tissue layers around the abdomen (ZFS0), and the skeleton on the left and right sides of the umbilicus. It appears as the impedance of the muscle tissue layer (ZMM1, ZMM2), the impedance of the visceral adipose tissue near the umbilicus (ZFV1, ZFV2), and the impedance of the internal organ tissue (ZVM) near the center of the trunk.

  FIG. 9 shows a circuit obtained by further simplifying FIG. Since ZFS1 and ZFS2 are considered to have substantially the same size, they are collectively represented as ZFS here, and ZMM1 and ZMM2 or ZFV1 and ZFV2 are represented as ZMM and ZFV, respectively. In addition, ZFS0, which is considered to be significantly lower in conductivity than other regions, is omitted. The point where this can be omitted will be apparent from the description in the previous section “1. Modeling an electrical equivalent circuit of the trunk tissue” (1).

  Next, the relationship between the interelectrode distance and the spreading resistance in the four-electrode method will be described with reference to FIG. FIG. 10 shows the relationship between the distance between electrodes and spreading resistance. In the figure, a portion 300 surrounded by a round dotted line is a spreading resistance region. The current from the current application electrode gradually spreads in the subject's body after application, but in the region immediately after application, that is, in the spreading resistance region, it does not spread so much. The density will be very high compared to other areas. Therefore, when the current application electrode 13 and the voltage measurement electrode 14 are arranged too close to each other, the potential difference measured at the voltage measurement electrode 14 spreads and is greatly affected by the current density concentration in the resistance region.

For example, as is apparent from Equation 2 described above, the impedance of the subcutaneous fat tissue layer (ZFS) near the umbilicus, the impedance of the skeletal muscle tissue layer (ZMM), the impedance of the visceral fat tissue (ZFV), and the center of the trunk Between the impedance (ZVM) of nearby internal organ tissues,
ZFS >> (ZVM + ZFV) >> ZMM ... Formula 2
There is a relationship.
Therefore, the potential difference measurement impedance ΣZ1 when arranged close to each other with almost no distance between the IV electrodes is as follows:
ΣZ1 = 2 * ZFS + ZMM // (ZVM + ZFV) ≈2 * ZFS
It becomes. As is clear from this, ZFS is amplified several times under the influence of spreading resistance, and information by ZFS is dominant here.

In order to reduce the influence of the spreading resistance, it is necessary to increase the distance between the current application electrode and the voltage measurement electrode. For example, the potential difference measurement impedance ΣZ2 when the distance between the IV electrodes is secured to about 10 cm is
ΣZ2≈2 * ZFS + ZMM // (ZVM + ZFV)
It becomes. By increasing the distance between the IV electrodes, the influence of the spreading resistance is somewhat reduced. However, the ZFS information is still dominant only by separating the distance.

In order to further reduce the influence of spreading resistance, as shown in FIG. 11, a case is considered in which about 10 cm is secured and arranged so that the distance between the IV electrodes and the VV electrodes is about 1/3 each. . In this case, the potential difference measurement impedance ΣZ3 is
ΣZ3≈2 * ZFS + ZMM // (ZVM + ZFV).
At this time, the relationship of the voltage drop measured between the electrodes is approximately as follows.
V1 = I * ZMM // (ZVM + ZFV)
V2 = V3 = I * 2 * ZFS
V1: (V2 + V3) ≈1-2: 10-20 = S: N
Here, S 1-2 and N 10-20 variation are due to individual differences in the thickness of the subcutaneous fat tissue layer and the development of the skeletal muscle tissue layer. As can be seen from this result, it is difficult to say that a sufficient S / N can be secured even if the distance between the electrodes is adjusted.

In addition, since most of the current is predominantly energized in the skeletal muscle tissue layer, it is not possible to sufficiently secure energization sensitivity to the composite tissue layer of internal organ tissue and visceral adipose tissue. That is, if the current flowing in the skeletal muscle tissue layer is I1, and the current flowing in the internal organ tissue and visceral fat tissue to be measured is I2,
V1 = I * ZMM // (ZVM + ZFV) = I1 * ZMM = I2 * (ZVM + ZFV)
I = I1 + I2
And therefore
ZMM: (ZVM + ZFV) = I2: I1≈1: 2-5
It becomes. As is clear from this, even if the influence of spreading resistance can be eliminated, the current flowing through the skeletal muscle tissue layer reaches 2-5 times the current flowing through the internal organ tissue and visceral adipose tissue. The S / N characteristic is further deteriorated. In this way, in a thick and short measurement site such as the trunk, even if the inter-electrode distance is adjusted, the upper limit is determined by the distance between the current electrodes, so there is a limit to the improvement of the S / N characteristics. .

  Therefore, according to the present invention, by energizing between the umbilicus recess and the spine, the amount of current applied to the internal organ tissue and the visceral fat tissue inside the skeletal muscle tissue layer is increased, and the measurement sensitivity to the visceral fat tissue is increased. Secure. 12 to 13 show a method for arranging electrodes according to the present invention. FIG. 12 shows the actual structure of the trunk abdomen from the front side and the back side, and FIG. 13 is a diagram schematically showing the structure of FIG.

  As shown in FIG. 13, the structure of the trunk abdomen is from the outside to the inside, the subcutaneous fat tissue layer (FS), the skeletal muscle tissue layer (MM), the visceral fat tissue (FV), and the internal organ tissue (VM). Represented as a layered structure of tissue. This is as shown in FIG. In the umbilical cavity and the spine, the FS is thin and the ZFS is small. That is, it is considered that ZMM <ZFS <Z (VM + FV).

  In the embodiment shown in FIGS. 12 to 13, one current application electrode 33 is disposed at the umbilical position A, and the other current application electrode 34 is disposed at the lower back waist (between the back umbilical circumference and the upper sacrum). ing. One electrode 36, 37 of the voltage measurement electrode pair for visceral adipose tissue measurement is arranged a little apart until the influence of the spreading resistance in the vicinity of the current application electrode can be ignored.

When a current I is applied between the electrode 33 and the electrode 34, the current flows along a path as indicated by a broken line in FIG. Therefore, the potential V1 measured by the electrodes 36 and 37 is a visceral adipose tissue measurement potential difference, and the measurement range of V1 is indicated by S1. The current-applying electrode position selected here has a very thin subcutaneous adipose tissue layer on both the front umbilicus and the lower back lumbar area, making it easy to secure the distance between the IV electrodes to avoid the influence of spreading resistance. Just fine. Therefore, the following impedance is obtained from I and V1.
Ztm = V1 / I = ZMM // (ZVM + ZFV)

  Here, Ztm is the combined impedance of the trunk abdomen captured by the voltage measurement electrodes 36 and 37. This is the same as Equation 4 above. Therefore, the amount of visceral adipose tissue can be measured by the method described above.

  As shown in FIG. 15, the position of the back surface side current application electrode 34 can be arranged in the range from the position (height) of the umbilicus A to the joint aponeurosis between the left and right gluteus muscles 42. In FIG. 15, S <b> 4 indicates an allowable range of the current application electrode arrangement of the electrode 34.

  Next, referring to the basic flowchart shown in FIG. 17 and the subroutine flowcharts shown in FIGS. 18 to 23, the operation of the trunk visceral fat measuring device in the embodiment of the present invention shown in FIGS. The operation will be described.

  In the basic flowchart shown in FIG. 17, first, when a power switch (not shown) in the operation unit 51 is turned on, power is supplied from the power supply unit 18 to each part of the electrical system, and the display unit 52 includes the height and the like. A screen for inputting body specifying information (height, weight, sex, age, etc.) is displayed (step S1).

  Subsequently, according to this screen, the user inputs height, weight, sex, age, and the like from the operation unit 51 (step S2). In this case, the body weight may be input from the operation unit 51. However, data measured by a body weight measuring device (not shown) connected to the main body unit 11 is automatically input, and calculation / control is performed. The body specifying information (weight) may be calculated by the unit 21. These input values are stored in the storage unit 4.

  Next, in step S3, it is determined whether or not morphometric measurement actual values such as trunk length and abdominal circumference length are input. If these morphometric measurement actual values are input, morphometric measurement is performed in step S4. The actual values such as the trunk length and the waist circumference are input from the operation unit 51, and the process proceeds to step S6. If it is determined in step S3 that the morphometric measurement actual value is not input, the process proceeds to step S5. These input values are also stored in the storage unit 4. Similarly, numerical information obtained in the following processing is stored in the storage unit 4.

  In step S <b> 5, the calculation / control unit 21 estimates the middle trunk length, the abdominal circumference length, and the like from the body specifying information such as the height, weight, sex, and age stored in the storage unit 4 ( For example, a calibration curve created from a human body information database is used).

  Subsequently, in step S6, the impedance measurement unit performs trunk impedance (Zx) measurement processing. In this trunk impedance measurement process, the trunk middle impedance (Ztm) and the subcutaneous fat tissue layer impedance (ZFS) are measured. This trunk impedance measurement process will be described later with reference to a subroutine flowchart shown in FIG.

  Next, in step S7, the calculation / control unit 21 performs a trunk skeletal muscle tissue cross-sectional area amount (AMM) estimation process. This calculation process is performed based on the above-described Expression 5 using, for example, the height H, the weight W, and the age Age stored in the storage unit 4.

  Next, in step S8, the calculation / control unit 21 performs trunk skeletal muscle tissue layer impedance (ZMM) estimation processing. This ZMM is performed based on the above-described equation 6 using the height H stored in the storage unit 4 and the AMM obtained in step S7.

  Next, in step 9, the calculation / control unit 21 performs an estimation process of the subcutaneous fat tissue mass (AFS). Step 9 will be described in detail later with reference to a subroutine flowchart shown in FIG.

  In step S10, the calculation / control unit 21 performs an internal organ tissue amount (AVM) and internal organ tissue impedance (ZVM) estimation process. Step 10 will be described in detail later with reference to a subroutine flowchart shown in FIG.

  In step S11, the calculation / control unit 21 performs a visceral fat tissue impedance (ZFV) and visceral fat tissue amount (AFV) estimation process. Step 11 will be described later in detail with reference to a subroutine flowchart shown in FIG.

  Next, in step S12, the calculation / control unit 21 performs a calculation process of the visceral fat / subcutaneous fat ratio (V / S). This process is performed according to the above-described equation 13 stored in the storage unit 4.

Next, in step S <b> 13, the calculation / control unit 21 performs a physique index (BMI) calculation process. This calculation process can be calculated from the weight W and the height H stored in the storage unit 4 by the following formula.
BMI = W / H ²

Furthermore, in step S14, the calculation / control unit 21 performs a calculation process of the trunk body fat percentage (% Fatt). This calculation process is based on the amount of subcutaneous fat tissue (AFS), visceral fat tissue (AFV), trunk skeletal muscle tissue cross-sectional area (AMM), and internal organ tissue (AVM) stored in the storage unit 4. It is calculated by the following formula.
% Fatt = (AFS + AFV) / [(AFS + AFV) + AMM + AVM] * 100

Next, in step S15, the calculation / control unit 21 performs a calculation process of the visceral fat rate (% VFat). This process is performed by the following formula from the trunk body fat percentage (% Fatt) and the visceral fat / subcutaneous fat ratio (V / S) calculated by the above-described calculation process and stored in the storage unit 4.
% VFat =% Fatt * (V / S) / [(V / S) +1]

  Finally, in step S16, the calculation / control unit 21 calculates the visceral fat tissue information (AFV,% VFat), body composition information (% Fatt, AMM, AFS, AVM) obtained by the calculation process as described above, A display process is performed to display a physique index (BMI), advice guidelines obtained by a process described later, and the like on the display unit 52. Thereby, a series of processes is completed (step S17).

  Next, the subcutaneous fat tissue mass (AFS) estimation process in step S9 will be described in detail with reference to the subroutine flowchart of FIG. This estimation process is performed in step S18 using the numerical values stored in the storage unit 4 and the above-described equation 12.

  Next, the internal organ tissue amount (AVM) and internal organ tissue impedance (ZVM) estimation processing in step S10 will be described in detail with reference to the subroutine flowchart of FIG. In this estimation process, the internal organ tissue amount (AVM) is calculated using the numerical values stored in the storage unit 4 and the above-described equation 7 in step S19, and the numerical values stored in the storage unit 4 in step S20. And using Equation 8 above.

  Next, the visceral adipose tissue impedance (ZFV) and visceral adipose tissue volume (AFV) estimation processing in step S11 will be described in detail with reference to the subroutine flowchart of FIG. In this estimation process, the visceral fat tissue impedance (ZFV) is calculated using the numerical values stored in the storage unit 4 and the above-described equation 10 in step S21, and the height H stored in the storage unit 4 in step S22. And the visceral fat tissue amount (AFV) is calculated using the calculated visceral fat tissue impedance (ZFV) and the above-described equation 11.

  Next, the trunk impedance (Zx) measurement process in step S6 will be described in detail with reference to the subroutine flowchart of FIG. 21 showing the first embodiment. In the first embodiment, the preceding section 7. As described in (12) and (13), the “removal effect removal process due to respiration” and the “abnormal value determination process due to eating and drinking and water retention (urine etc.) in the bladder” are performed. First, in step S23, the calculation / control unit 21 performs initial setting of a counter or the like, for example, the number of samples of measurement data of the trunk impedance Ztm and the initial setting of the flag F based on an instruction from the operation unit 51 or the like. Do. F is a flag symbol of “1” and “0”.

Subsequently, in step S24, the calculation / control unit 21 determines whether or not it is a measurement timing. And when it is determined as the measurement timing, in steps S25a to S25b, the calculation / control unit 21 performs measurement electrode arrangement setting processing of trunk trunk impedance (Ztm) and subcutaneous fat tissue layer impedance (ZFS), Measurement processing of trunk impedance (Ztm _x ) and subcutaneous fat tissue layer impedance (ZFS _x ) is performed. In this subroutine flowchart, it is assumed that measured values of trunk impedance (Ztm) and subcutaneous fat tissue layer impedance (ZFS) are obtained. In this case, the calculation / control unit 21 measures measured values of each trunk impedance. Measurement processing of (Ztm _x ) and (ZFS _x ) is performed. In other words, from the measured value by measuring the visceral fat tissue measured electric potential difference V1 or subcutaneous fat tissue layer measured potential difference V2 and V3, to calculate the Ztm _x and ZFS _x.

  Next, when it is determined in step S24 that it is not the measurement timing, the process proceeds to step S26, and measurement impedance (Zx) data smoothing processing (moving average processing or the like) is performed. Then, in step 27, trunk impedance measurement data breathing fluctuation correction processing is performed. This correction processing will be described later with reference to the subroutine flowchart of FIG.

  Subsequently, in step S28, the calculation / control unit 21 performs time-series stability confirmation processing of the measurement impedance for each part. This is performed by determining whether or not each value after the trunk impedance measurement data breathing fluctuation correction process in step S27 has converged to a value within a predetermined fluctuation a predetermined number of times.

In step S29, the arithmetic and control unit 21, measured Ztm _x and ZFS _x is to determine whether to satisfy the stability condition. This determination is such that it is determined that the respiration median value is determined when the respiration median value for each respiration cycle enters a stable range within the specified number of times. If it is determined in step S29 that the stability condition is satisfied, the process proceeds to step S30, where the determined impedance value of the median is used as the impedance value of the trunk, and the final stability condition determination value is the measurement result value. Is registered in the storage unit 4 as follows. On the other hand, if it is determined in step S29 that the stability condition is not satisfied, the process returns to step S24 and the same processing is repeated.

  Subsequent to step S30, in step S31, the calculation / control unit 21 performs an abnormal value determination process such as eating and drinking and urinary bladder retention, and in step S32, the notification buzzer 22 indicates the completion of the measurement (see FIG. 4). Using a buzzer or the like to notify the user, the measurement is completed. The abnormal value determination process in step 31 will be described later with reference to the subroutine flowchart of FIG.

Next, the trunk impedance measurement data respiration variation correction process in step S27 will be described in detail with reference to the subroutine flowchart of FIG. First, in step S33, the calculation / control unit 21 performs an inflection point detection process from the time-series data processed in step S27. In step S34, it is determined whether or not it is an inflection point. This is performed by detecting data of polarity change positions of the front and rear derivatives or difference values. When it is determined in step S34 that the point is an inflection point, the process proceeds to step S35, and it is determined whether or not the maximum value is reached. This is a step of distributing the maximum value and the minimum value. When it is not the maximum value, the minimum value determination data moving average process is performed by the following equation stored in the storage unit 4 in step S36.
[Ztm] min _x ← ([Ztm] min _x-1 + [Ztm] min _x ) / 2

When it is determined in step S35 that the maximum value is obtained, in step S37, the maximum value determination data moving averaging process is performed using the following equation stored in the storage unit 4.
[Ztm] max _x ← ([Ztm] max _x-1 + [Ztm] max _x ) / 2

Subsequently, in step S38, it is determined whether the maximum value and minimum value data for one breathing cycle have been secured. When it is determined in step S38 that the data has been secured, in step S39, the respiratory fluctuation median value calculation process (average value of maximum value and minimum value data) is calculated using the following equation stored in the storage unit 4. Operation).
Ztm _x ← ([Ztm] max _x + [Ztm] min _x ) / 2

Next, the abnormal value determination processing based on eating and drinking and urinary bladder retention in step S31 will be described in detail with reference to the subroutine flowchart of FIG. First, in step S40, the calculation / control unit 21 checks whether the trunk impedance (Ztm) is within the normal allowable range using the following equation stored in the storage unit 4.
Mean-3SD ≦ Ztm ≦ Mean + 3SD
Here, as an example of the allowable value, 3SD is conceivable with respect to 26.7 ± 4.8 (Mean ± SD).

  In step S41, it is determined whether the trunk impedance is within an allowable range. When it is determined that the value is not within the allowable range, the process proceeds to step S42, where the arithmetic / control unit 21 performs message notification processing regarding a trunk (abdomen) condition abnormality, and displays appropriate advice on the display unit 52. Etc. are made. As this advice, for example, a notification such as “performing a preparation process such as defecation and urination for abnormal trunk condition” can be considered. Further, when the same determination result is obtained after the preparation process, the measurement can be completed using the abnormal value, and the measurement can be stopped.

  When it is determined within the allowable range in step S41, in step S43, the calculation / control unit 21 performs message notification processing regarding normal condition of the trunk (abdomen) condition, and displays appropriate advice on the display unit 52. Made. As this advice, for example, notification such as “normal trunk condition” can be considered.

  With such operations and operations, according to the present invention, visceral adipose tissue information of the trunk (trunk abdomen) can be obtained, and furthermore, the influence removal process of fluctuation due to breathing, and the moisture in the bladder and the like It is possible to perform abnormality determination processing due to storage (such as urine) and provide advice information accordingly. In the above-described embodiment, the fat percentage is obtained as the trunk visceral fat tissue information. However, the present invention is not limited to this, and by using an appropriate conversion formula, the cross-sectional area amount and the volume amount are obtained. Or weight.

It is a schematic perspective view which shows the external appearance of one Example of the trunk visceral fat measuring device by this invention. FIG. 2 is a diagram illustrating how the apparatus of FIG. 1 is used. It is the schematic perspective view and sectional drawing which show the external appearance of one Example of the current application electrode arrange | positioned in a umbilical-position. It is a block diagram of the main-body part of the trunk visceral fat measuring device by this invention. It is a figure which shows typically the structure of a trunk abdomen. It is a figure explaining the mode of electricity supply by the conventional method. It is a figure explaining the mode of electricity supply by the present invention. It is the figure which modeled the schematic diagram of the trunk shown by FIG. 5 in the abdominal circumference cross section in umbilical height. It is the figure which represented the model figure of FIG. 7 as an electrical equivalent circuit. 9 is a simplified diagram of the circuit of FIG. It is a figure explaining the relationship between the distance between electrodes, and spreading resistance. It is a figure explaining the relationship between the distance between electrodes, and spreading resistance. It is a structural view of the trunk abdomen showing an example of electrode arrangement according to the present invention. It is a figure which shows typically the structure of the trunk abdominal part of FIG. It is a structural view of the trunk abdomen showing an example of electrode arrangement according to the present invention. It is a structural view of the trunk abdomen showing an example of electrode arrangement according to the present invention. FIG. 15 is a cross-sectional view of the umbilical region where the electrodes of FIG. It is a figure which shows the basic flowchart for trunk visceral fat measurement by one Example of this invention. It is a figure which shows the estimation processing flow of the amount of subcutaneous fat tissues as a subroutine of the basic flow of FIG. It is a figure which shows the estimation processing flow of the internal organ tissue quantity and internal organ tissue impedance as a subroutine of the basic flow of FIG. It is a figure which shows the estimation processing flow of the visceral fat tissue impedance and visceral fat tissue amount as a subroutine of the basic flow of FIG. It is a figure which shows the trunk impedance measurement process flow as a subroutine of the basic flow of FIG. FIG. 22 is a diagram showing a trunk impedance measurement data respiration variation correction process flow as a subroutine of the trunk impedance measurement process flow of FIG. 21. It is a figure which shows the abnormal value determination processing flow by eating and drinking, urinary bladder retention, etc. as a subroutine of the trunk impedance measurement processing flow of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Trunk visceral fat measuring apparatus 5 Operation display panel 11 Main body part 12 Band 13 Current application electrode 14 Voltage measurement electrode 21 Calculation / control part 51 Operation part 52 Display part 130 Grip electrode part 140 Grip electrode part A Umbilical 30 Abdominal rectus muscle tissue Layer 31 outer oblique oblique tissue layer 40 tendon 41 white line 42 gluteal muscle 43 latissimus dorsi muscle S1 V1 measurement range S4 current application electrode arrangement allowable range S5 voltage measurement electrode arrangement allowable range 33, 34 current application electrode 36, 37 voltage measurement electrode

Claims (22)

  A trunk visceral fat measurement method for obtaining a trunk visceral fat tissue amount using a bioimpedance of the trunk measured using a current application electrode pair and a voltage measurement electrode pair arranged on the trunk or the trunk and extremities The method for measuring a visceral fat in a trunk, wherein a current applying electrode of the current applying electrode pair is placed in the umbilical position to energize an internal organ tissue and a visceral fat tissue inside the trunk.   2. The trunk visceral fat measurement method according to claim 1, wherein at least a part of the one current application electrode is inserted into a concave portion of the navel.   The trunk visceral fat measuring method according to claim 2, wherein at least a part of the one current application electrode is brought into close contact with the concave portion of the navel.   The trunk visceral fat measuring method according to any one of claims 1 to 3, wherein the other current applying electrode of the current applying electrode pair is disposed in a spine position.   5. The trunk visceral fat measurement method according to claim 4, wherein the other current application electrode is disposed on the spine umbilical circumference or the waist part slightly below the spinal umbilical circumference.   One voltage measurement electrode of the voltage measurement electrode pair is arranged in the vicinity of the umbilical cord, and the other voltage measurement electrode is secured by a distance that can avoid the influence of spreading resistance due to the other current application electrode, and the other current application 6. The trunk visceral fat measurement method according to claim 5, wherein the trunk visceral fat measurement method is arranged slightly above the umbilical circumference or the spine umbilical field in the trunk longitudinal direction from the position of the electrode.   The trunk visceral fat measuring method according to any one of claims 1 to 3, wherein the other current applying electrode of the current applying electrode pair is arranged on an extremity.   The other current application electrode is disposed on one of the left and right upper limbs, one voltage measurement electrode of the voltage measurement electrode pair is disposed near the umbilical position, and the other voltage measurement electrode of the voltage measurement electrode pair is disposed on the left and right The trunk visceral fat measuring method according to claim 7, wherein the trunk visceral fat measuring method is arranged on the other of the upper limbs.   The other current application electrode is disposed on either the left or right lower limb, one voltage measurement electrode of the voltage measurement electrode pair is disposed near the umbilical position, and the other voltage measurement electrode of the voltage measurement electrode pair is disposed on the left or right side. The trunk visceral fat measuring method according to claim 7, wherein the trunk visceral fat measuring method is arranged on the other of the lower limbs.   The trunk skeletal muscle tissue amount is obtained based on the body specific information, the impedance of the trunk skeletal muscle tissue layer is obtained based on the obtained trunk skeletal muscle tissue amount and the body specific information, and the body specific information is obtained. The internal organ tissue amount of the trunk is determined based on the internal organ tissue amount of the trunk and the body specifying information, the impedance of the internal organ tissue of the trunk is determined, and the biological impedance of the trunk, Obtaining the impedance of the trunk visceral adipose tissue based on the obtained impedance of the trunk skeletal muscle tissue layer and the impedance of the internal organ tissue of the trunk, the impedance of the obtained trunk visceral adipose tissue and body specifying information, The trunk visceral fat measuring method according to any one of claims 1 to 9, wherein the trunk visceral fat tissue amount is obtained based on the above.   The step of determining the impedance of the trunk visceral fat tissue based on the bioimpedance of the trunk, the impedance of the trunk skeletal muscle tissue layer and the impedance of the internal organ tissue of the trunk The circuit is characterized in that the impedance of the trunk skeletal muscle tissue layer is connected in parallel to the series circuit of the impedance of the internal organ tissue of the trunk and the impedance of the trunk visceral fat tissue The trunk visceral fat measuring method according to claim 10.   A trunk visceral fat measuring device that determines the amount of trunk visceral fat tissue using the bioimpedance of the trunk measured using a current applying electrode pair and a voltage measuring electrode pair arranged on the trunk or the trunk and extremities The trunk visceral fat measuring device according to claim 1, wherein one current applying electrode of the current applying electrode pair is arranged at the umbilical position.   13. The trunk visceral fat measuring device according to claim 12, wherein the one current applying electrode has a shape extending so as to be inserted into a concave portion of the navel.   14. The trunk visceral fat measuring device according to claim 13, wherein the one current application electrode has a portion that can be in close contact with the concave portion of the navel.   The trunk visceral fat measuring device according to any one of claims 12 to 14, wherein the other current applying electrode of the current applying electrode pair is arranged in a spine position.   16. The trunk visceral fat measuring device according to claim 15, wherein the other current application electrode is arranged on a spine umbilical circumference or a waist part slightly below the spinal umbilical circumference.   One voltage measurement electrode of the voltage measurement electrode pair is arranged in the vicinity of the umbilical cord, and the other voltage measurement electrode secures a distance that can avoid the influence of spreading resistance due to the other current application electrode, and applies the other current application. The trunk visceral fat measuring device according to claim 16, wherein the trunk visceral fat measuring device is arranged slightly above the umbilical circumference or the spine umbilical circumference in the trunk longitudinal direction from the position of the electrode.   The trunk visceral fat measuring device according to any one of claims 12 to 14, wherein the other current applying electrode of the current applying electrode pair is arranged on an extremity.   The other current application electrode is disposed on one of the left and right upper limbs, one voltage measurement electrode of the voltage measurement electrode pair is disposed near the umbilical position, and the other voltage measurement electrode of the voltage measurement electrode pair is disposed on the left and right The trunk visceral fat measuring device according to claim 18, wherein the trunk visceral fat measuring device is arranged on the other of the upper limbs.   The other current application electrode is disposed on one of the left and right lower limbs, one voltage measurement electrode of the voltage measurement electrode pair is disposed near the umbilical position, and the other voltage measurement electrode of the voltage measurement electrode pair is disposed on the left and right legs. The trunk visceral fat measuring device according to claim 18, wherein the trunk visceral fat measuring device is arranged on the other of the lower limbs.   The trunk bioimpedance measuring means for measuring the bioimpedance of the trunk, the trunk skeletal muscle tissue amount is estimated based on the body specifying information, and the estimated trunk skeletal muscle tissue amount and the body specifying information A trunk skeletal muscle tissue layer impedance estimating means for estimating the impedance of the trunk skeletal muscle tissue layer based on the body specific information, estimating the internal organ tissue amount of the trunk based on the body specifying information, and the estimated internal organ of the trunk Intracorporeal organ tissue impedance estimating means for estimating the impedance of the internal organ tissue of the trunk based on the tissue amount and the body specific information, the bioimpedance of the trunk, and the estimated trunk skeletal muscle tissue layer Trunk visceral fat tissue impedance estimating means for estimating impedance of trunk visceral fat tissue based on impedance and impedance of internal organ tissue of the trunk; 21. A trunk visceral adipose tissue amount estimation means for estimating a trunk visceral adipose tissue amount based on the impedance of the visceral trunk visceral adipose tissue and the body specifying information is further provided. The trunk visceral fat measuring device according to claim 1.   The trunk visceral adipose tissue impedance estimator means that the trunk's electrical equivalent circuit is connected to the trunk skeletal muscle with respect to a series circuit of the impedance of the internal organ tissue of the trunk and the impedance of the trunk visceral fat tissue. The trunk visceral fat measuring apparatus according to claim 21, wherein the estimation is performed assuming that the impedance of the tissue layer is connected in parallel.

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