CA1315848C - System for body impedance data acquisition - Google Patents
System for body impedance data acquisitionInfo
- Publication number
- CA1315848C CA1315848C CA000600366A CA600366A CA1315848C CA 1315848 C CA1315848 C CA 1315848C CA 000600366 A CA000600366 A CA 000600366A CA 600366 A CA600366 A CA 600366A CA 1315848 C CA1315848 C CA 1315848C
- Authority
- CA
- Canada
- Prior art keywords
- patient
- impedance
- data acquisition
- bio
- impedance data
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/48—Other medical applications
- A61B5/4869—Determining body composition
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/05—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves
- A61B5/053—Measuring electrical impedance or conductance of a portion of the body
- A61B5/0537—Measuring body composition by impedance, e.g. tissue hydration or fat content
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/48—Other medical applications
- A61B5/4869—Determining body composition
- A61B5/4872—Body fat
Landscapes
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Surgery (AREA)
- Biophysics (AREA)
- Pathology (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
- Medical Informatics (AREA)
- Molecular Biology (AREA)
- Physics & Mathematics (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Radiology & Medical Imaging (AREA)
- Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
- Measuring And Recording Apparatus For Diagnosis (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
The unique system of the present invention provides an accurate valid measurement of human body composition consisting of fat tissue, lean tissue and body water. The inventive methodology provides a procedure for quantitative measurement of the conductive potential of the body, which is based on the lean tissue content of the body, in a convenient and reliable manner.
In more detail, the quantitative measurement in accordance with the present invention is referred to as a "bio-impedance signal." This electrical signal, in ohms, is derived from a means for measuring body impedance component of the system. The resultant signal (three digit number, between 1 and 1000 ohms) is then entered into a modifying means component to accurately predict the body composition of the tested individual. The unique modifying means, in one embodied form, comprises prediction formulas derived from biological data inputs including: a patient's height, weight, age and sex, to determine a "population prediction variable." Thus, the unique modifying means of the inventive system interprets bio-impedance readings as "population specific", i.e., specific impedance values are exhibited by various pre-defined populations of individuals.
This specificity is related to morph-type, leanness, body water and age. In accordance with the present invention, an algorithm formula approach to prediction formulas is utilized to define an appropriate individual or set of variables.
The unique system of the present invention provides an accurate valid measurement of human body composition consisting of fat tissue, lean tissue and body water. The inventive methodology provides a procedure for quantitative measurement of the conductive potential of the body, which is based on the lean tissue content of the body, in a convenient and reliable manner.
In more detail, the quantitative measurement in accordance with the present invention is referred to as a "bio-impedance signal." This electrical signal, in ohms, is derived from a means for measuring body impedance component of the system. The resultant signal (three digit number, between 1 and 1000 ohms) is then entered into a modifying means component to accurately predict the body composition of the tested individual. The unique modifying means, in one embodied form, comprises prediction formulas derived from biological data inputs including: a patient's height, weight, age and sex, to determine a "population prediction variable." Thus, the unique modifying means of the inventive system interprets bio-impedance readings as "population specific", i.e., specific impedance values are exhibited by various pre-defined populations of individuals.
This specificity is related to morph-type, leanness, body water and age. In accordance with the present invention, an algorithm formula approach to prediction formulas is utilized to define an appropriate individual or set of variables.
Description
BACKGROUND OF THE~ TION
This invention relates to a system for conveniently and accurately measuring anA quantitating the conductive potential of a human body which is based on a determination of lean tissue content.
Obesity has truly been declared, as of ~985 by the National Institute of Health, a stand-alone risk factor. In fact, obesity has been declared as a disease unto itself. It is now a new medical standard that obesity needs to be diagnosed and treated by a physician for the health and well-being of the general public.
A true definition of "obesity~ has been difficult to define, in that such definition is dependent upon a percent body fat determination.
Historically, "percent body fat" has been determined in research laboratories by dunking people in a hydrostatic tank to perform a hydrostatic critereon method for quantification of body fat.
Hydrodensitometry (water tank immersion) has been generally considered to be the traditional standard for body composition analysis. Despite the biological and experimental errors inherent in hydrodensitometry (Lohman, T.G., Skinfolds and Body Density and Their Relation to Body Fatness: A Review, Human Bioloav, 53~ 181-225), all other methods of analysis must be oompared to it if they are to be validated.
Another k~own method for body fat analysis is skinfold ~ 3 ~
anthropometry (calipers). However, many skilled health care practitioners have questioned this methodology for body composition analysis in that reliability is doubtful. In the hands of trained technicians, anthropometry can give errors of plus or minus nine percent (9~) when compared to densitometry ~Katch, F.I., Katch, V.L. (1980), M~asurement and Prediction Errors in Body Composition Assessment and the Search for the Perfect Equation. _esearch Ouarterly for Exercise and Support, Vol. 51, No. 1, 249-260). In general zlinical use in the hands of a variety of trained examiners wikh less than expert skill, the error in the caliper technique is presumably even greater.
Recently, body composition analyzers have been introduced that utilize a relatively new technology known as tetrapolar bio-electrical impedance.
Most importantly, through tetrapolar bio-electrical technology, the test/retest reliability has been reported as 0.5% (Lukaski, H.C., Johnson, P E., Bolonchuck, W.W., and Lykken, G.I., Assessment of Fat-Free Mass Using Bio-Electrical Impedance Measurements of the Human Body) aompared to a test/retest reliability of 3.8% ~or hydrodensitometry.
In this respect, the human body is composed basically of two components--one is lean body mass, which is composed of muscle tissue, connective tissue and bones; and the other major component is body fat. Bio-electrical impedance technology quantifies the true ratio of these components--the difference between lean body mass, which is the healthy metabolising part, and the body fat, which is the storage o~ energy in your body.
~ 3 ~
Lean body mass has about 75% water; in contrast, fat is about 3%
to 13% water. Accordingly, ~io-electrical impedance technology measures the "healthy" part of the body, which is the lean body mass.
While known tetrapolar bio-electrical technology is considered ~y many to be an advance from hydrodensitometry, both from a reliability standpoint and convenience standpoint, known systems have produced inaccurate body composition analysis in that such known systems are dependent upon a linear regression equation approach. Moreover, much of the data derived from known bio-electrical impedance techniques fails to consider biological data of specific patient groups which may deleteriously affect the accuracy of the body composition analysis.
~ ccordingly, those skilled in the art have recognized a significant need for an accurate, valid measurement approach of human body composition. The present invention provides a procedure for quantitative measurement of the conductive potential of the body in a convenient and reliable manner and then provides the means for modifying that body impedance measurement with algorithm formula equations that generate scientifically validated predictions of :human body composition analysis. The present invention fulfills these needs~
UMMARY OF THE INVENTION
The unique system of the prPsent invention provides an accurate valid measurement of human body composition consisting of fat tissue, lean tissue and body water. The inventive methodology provides a procedur~ for quantitative measurement of the conductive potential of the body, which i5 based on the lean tissue content of the body, in a convenient and reliable manner.
In more detail, the quantitative measurement in accordance with the present invention is referred to as a "bio-impedance signal. n This electrical signal, in ohms, is derived from a means for measuring body impedance component of the system. The resultant signal (three digit number, between 1 and 1000 ohms~ is then entered into a modifying means component to accurately predict the body composition of the tested individual.
The unique modifying means, in one embodied form, comprises predi~tion formulas derived from biological data inputs including a patient's height, weight, age and sex, to determine a "population prediction variable."
Thus, the unique modifying means of the inventive system interprets bio-impedance readings as "population specificn, i.e., specific impedance values are exhibited by various pre-defined populations of individuals. This specificity is related to morph-type, leanness, body water and age. In accordance with the present invention, an algorithm formula approach to prediction formulas is utilized to define an appropriate individual into a set of population specific variabl s.
~L3~8~8 Initially, the bio-impedance siynal is imputed into the modifying means along with bioloyical data. Thereafter, algorithm formulas modify the inputted signals by the appropriate correction factor. The correction factor is generally non~linear and derived from comparison with known hydrostatically derived values to produce an output which may then be conveniently displayed by indicator means so that body composition can be predicted.
It will be appreciated from the foregoing that the present invention provides an accurate and convenient system for quantifying body fat as a percentage o~ waight which is an important health management tool for patient and physician alike.
Other features and advantages of the present invention will become apparent from the following, more detailed description, taken in conjunction with the accompanying drawings, which illustrate by way of example the principles of the invention.
~ 3 ~ 8 BRIEF DESCRIPTION OF THE DRAWING
Fi~ure 1 is a perspective view of first and second prescribed locations for locating electrode sensors in accordance with one embodiment of the present invention;
Figure 2 is a perspective view of second and third prescribed locations for locating electrode sensors in accordance with one embodiment of pres~nt invention;
Figure 3 is a schematic block diagram depicting one embodied form of the inventive system for body impedance data acquisition in accordance with the present invention;
Figure 4 is a circuit diagram of a test signal generator in accordance with one embodiment of the present invention;
Figure 5 is a circuit diagram oP a power supply for the inventive system in accordance with one embodied form of the invention;
Figure 6 is a circuit diagram o~ a sensor circuit in accordance with one embodied form of the present invention;
Figure 7 is an electrical circuit diagram of a pin-out diagram of a body impedance meter in accordance with one embodiment of the present invention;
Figure 8 is a schematic in more detail of a body impedance meter in accordance with one embodiment of the pr2sent invention;
Figure 9 is a perspective view of a suitable computer in accordance with one embodiment of the present invention;
Figure 10 is a chart of tests/re-test data comparison in accordance with the present inYention:
Fi~ure 11 is a chart of inter-meter comparisons in 7~164-7 accordance wlth the present lnventlon;
Flgure 12 ls a graph whlch reflects the total sample referred to in ~xample I ln accor~ance wl~h the present invention;
Flgure 13 ls a graph whlch reflects the female component of the total ~ample referred to in Example I ln accor~ance wl~h the present lnvention;
Flgure 14 ls a yraph whlch reflects the male component of the sample referred to in Example I ln accordance wlth the present inventlon; and Flgure 15 is a chart of the data list statement for the present invention.
~ESCRIPTION OF THE PR~F~RRE~ EMBODIM~NTS
.
As shown ln the drawlngs for purposes o~ illustratlon, the present lnvention is embodied ln a unlque system for acquisitlon of body impedance date, which comprises in combination:
a) a plurallty of electrode sensors for rnountlng to prescrlbed locatlons of a patlent's body to be analyzed;
~0 b) mounting means for removably attaching said electrode sensors to a Kelvin Brldge blo-lmpedance meter system havlng ~our terminal leads;
cl means for ~enerating a current flow through said electrode sensors at a frequency of from about 40 Kilohertz to about 60 Kilohertz, thereby producing an output range of 0 to l,000 ohms;
d) means for generatlng input variables comprlsed of biologlcal patient data lncludlng helght, weight, a~e, and sex ~ 3 ~ 8 and bio-impedance signal to determine a population specific variable;
e) means for manipulating said electrical siqnals derived from said means for generating a body impedance signal with said population prediction variables f) indicator means for displaying said resultant output signal to provide quantitative measurement of conductive potential of said patient's body based on lean tissue content of said patient; and g) means for comparing said resultant signal with known scatter grams to produce an output signal representative of fat tissue, lean tissue and body water.
In accordance with the present invention, an electrical Kelvin Bridge is created by a plurality of electrodes which are removably attached to specific body areas. In more detail, prior to sensor placement, each body location is palpated and preferably cleaned with an alcohol swab to remove skin or surface oils. Thereafter, each electrode sensor is placed on a patient's body. Preferably, a conductive gel is utilized to temporaily hold the sensor in place.
ELECTRODE SENSQR LOCATIONS
(1) The first prescribed location 10 is the back side of the patient's right hand. (~Dorsal Aspect.~) Locate the ~Styloid Precess.~ (The 'bump' near the back of the wrist.) Palpate approximaely .5 to 1 inch directly across from the ~ 3 ~ 8 ~styloid Processn" (Note the slight 'depression' between the "Radius" and nUlna.'J) The First Sensor is placed across from the "Styloid Pro~ess" in the middle of the wrist. (The Sensor centar should be directly over the slight 'depression' described above.) Note: Placing the elec~rodes so they 'point' away from the body is recommended. (See Figure 1) (2) The second prescribed location 12 is behind the knuckle (joint) of the index finger of the right hand. (~Distal end of the second metacarpal.~) Palpate this area. Place the Second Sensor directly on the hand behind, but not touching, the right index finger. (See Figure 1) (3) The third prescribed location 14 is the patient's ankle at the front of the right foot. (Inbetween the nMedial~ and ~Lateral Malleoli~--the 'bumps' on the inside and outside of the ankle.) Note the slight 'depression' in this area where the ankle meets the top of the foot. Palpate here. Place the Third Sensor so that its center directly covers the slight 'depression' described above. (See Figure 2) (4) The fourth prescribed location 16 is the top of the right foot behind the joint of the great toe. (The ~Distal"
portion of the ~irst ~metatarsal.~) Palpate this area. Place the Fourth Sensor on the top o~ the right ~oot, behind, but not touching the great toe. (See Figure 2) POWER SUPPLY
The power supply for the inventive system is preferably provided by a ~ingle nine (9) volt alkaline battery (See Figures ~ fi~?~58~
3 and 5). The circuit pathways are desi~ned for sa~ety and efficiency. A momentary on and off power switch is used to c~nser~e battery life. The bio-impedance metre test life expectancy is 500 tests.
TAe design of the power supply circuit allows a test signal and a sensor circuit to operate within given parameters without ~eing dependent upon a specific hattery chanye level. Diode protection is preferably provided both at the power source and at the power input section of the printed circuit board to insure against reverse current flow.
To maintain an optimal functioning range, the system generates a 5 volt charge to power the sensor and digital functions.
To provide a reliable and viable power source, a low battery ~LED) is displayed when the current power source (9 volt battery) drops below 6.2 volts.
The power drain of the LED will consume the remaining voltage within 30 seconds. Note~ The average commercial grade 9 volt alkaline battery is char~ed at 9.2 volts.
MEANS FOR GENERATING BODY IMP~DANCE SIGNAL
Preferably one 9~volt battery operates the means for generating body impedance signal. The technology utilizes a Kelvin Bridge system with 4 terminal leads. The Sensors previously described attaches to each terminal end and is placed on the patient for correct data Impedance acquisition~
~3~ 8 OPERATION
As described, the body impedance system generates a frequency which is totally undetectable to the human body.
After chec~ing that the four electrode sensors are properly placed, the patient remains prone and still.
The on/off switch is placed in the "on" position. The Meter takes Impedance readings at a rate of 50,000 times per second. Often the Meter takes 1 to 3 seconds to stabilize while 'searching' fox the most accurate reading. Several factors such as subcutaneal fat thickness, skin thickness and body hair account for slower impedance r~adings.
TECHNICAL SPECIFICATIONS
The preferred technical specifications of the means for generating body impedance system are as follows:
a) Device test signal current - about BOO microamps nominal;
b) Device test signal frequency - about 50 KHZ nominal;
c) Input range - O to 1000 ohms;
d) Input impedance - about 10 meg ohm;
e) Accuracy - about 1%;
f) Supply current (qeiecent) - about 70 MA nominal;
g) Negative supply battery range - about 8.5 to 10 volts;
h~ Positive supply battery range - about 8.5 to 10 volts;
i) Battery polarity protection - Dual diode.
~s~ 8 SCHEMATIC DIAGRA~
The pin-out diagram illustrated in Figure 7 det~ils one embodied printed circuit board for the means for generating body impedance system.
The details of the schematic are presented in the following sections:
1) Sensor circuit; and 2~ Test signal generation.
Each of these sections will refer to block diagrams to highlight the ~xact electronic con~iguration.
SENSOR CIRCUIT
Figures 3 and 6 are blocX diagrams detailing one embodied sensor circuit o* the impedance meter. The electronic circuitry and components include the analog to digital (A to D) technology.
To obtain valid bio-impedance measurements, a true tetra - polar bridge system must be employed. The circuit in application provides a tetra-polar bridge (four lead bridge).
The sensor circuit pre~erably operates at an BOO microamp level. The sensor current combined with the test signal generation, powers the inventive system.
As outlined previously, the bio-impedance analyzer is connected to the body by ~our leads, two connected to the right hand and two to the ri~ht ~oot. The sensing current is then placed between the poles.
TEST SIGNAL GENERATION ~ 3 ~ ~ ~ 4 ~
A test signal i5 maintained through the components with a frequency of between 40 to 60 Kilohertz and pre~erably at 50 KiloHertz. The block diagram illustrated by Figures 3 and 4 de~ails the specifica~ions and current flow of the bio~impedance analyzer. The test signal configura ion is calibrated at the 500 ohms level, selected as a mid-point in the bio-impedance analyzer reading scale of 1 to 1000 ohms.
The test signal generator remains constant due to the constant voltage of 5 volts from the power supply. A constant power supply of 5 volts is critical for the re-producability of data obtained from the bio impedance analyzer. A low battery indicator calibration for 6.2 volts ensures a constant 5 volt current source.
MODIFICATION OF IMPEDANCE SIGNALS
The raw electrical signals ~rom the impedance meter are modified by a prescribed correlation factor of body density.
(BD = 1,14111-.0763 (weight) (impedance/height2).
Based on a given body density a ~range of impedance readings" is expected. This range is population specific. Thus, once body density is derived and compared to impedance, a constant is then selected for the body analysis formula.
Figure 8 represents one embodied individual progression through a population prediction formula.
a) Biological data input-1) Bio-impedance 2) Age ~3~
3) Height 4) Weight Sex b) Algorithm formula determinatio~ ~f body analysis formula constant based on body density and impedance:
e.g. If body denisty is ( 1.9 and impedance (400 then X
= 2.835 Note: X is the body analysis formula constant.
c) Population Prediction formula:
After phase one (a) and two (b) are complete, the main prediction formula which has been modified by the algorithm analyzes the data to predict body composition.
e.g. Percent fat = (4.95 / x - 4.5) Note: X is the constant ~rom the algorithm.
The inventive system preferably includes an attached micro-processor to perform the data processing tasks for body composition testing and analysis. The Computer desirable and has capacity for expandable features. (See Figure 9) Preferably the Computer is permanently mounted and cannot be removed from a transport case. A 6 volt adapter may be used to power the micro-processor.
~ 3 ~ g INDICATOR MEANS FOR DISPLAYING DATA
Preferably a Printer such as OKI-DATA 182 microline is utilized in the system. A brief explanation for operation is provided herein.
TEST PROCEDURE
Height/Weight and Proper Patient Position (1) Record patient's height and weiyht. (Height in inches, weight in pounds.) Do not use data supplied by patient.
Accurate height and weight measurements are essential for accurate results. ~emove patient's shoes for both measurements.
Also remove the sock/hose on the right foot. (The site for distal electrode sensor placement.) (2) Position the patient prone on a non-conductive surfaced table. Do not test a patient lying on a tile or carpeted ~loor.
Statis electricity contained in these surfaces interferes with accuracy. The patient must be prone to minimize interference from muscle contractions. (Antagonist muscle contractions in standing or sitting patients create inaccurate Impedance results.) (3) Arrange the patient'~ limbs so they are slightly apart, hands not touching the torso, feet not touching each other.
OPERATION CHECK LIST
a) Attach Electrode Sensors to Patient Lead Cables.
b) Remove Patient's shoes and right sock/hose.
c) Measure Patient's height.
~3~ ~$~8 d) Weigh patient.
e~ Record Patient Height and Weight on Patient Data Form.
f) Place Patient prone on table.
g) Palpate Electrode Sensor locations.
h~ Place Electrode sensors to right hand and right foot.
i) Collect Patient Impedance reading~
j) Record Impedance reading on Pa~ient Data FormO
k) Select program on the Main Menu and ENTERo 1) ENTER information needed for Patient Data Input.
m) Remove Printout from the Printer.
IILUS?RA?IVE EXAMPLES
The following specific examples will be helpful to a clearer understanding of the unique features of the present invention:
Example I:
A study was conducted to evaluate the validity of bio-electrical impedance as an accurate assessment of body composition. Two-hundred and ~orty nine male and female volunteers from the University of Southern California were used as subjects. Each subject reported to the Exercise Physiology lab at USC in a normally hydrated state. Body composition evaluation was made by hy~rostatic weighing (H20) and bioelectrical impedance ~Imp)~ Hydrostatic weighing was done in a seated position in a 1~00 gallon tank using a Chatillon autopsy scale. A minimum of 5 trials was made on each subject. Residual lung volume was measured utilizing the oxygen dilution technique and employing ~ ~lewlett-Paclcard Ni.trogen analyzer. Body fat was calculated using the formula of Brozek, et al. (~.57/Density -4.142 x 100%). Bio-electrical impedance was measured on each subject employing the sta~dard procedures ~or the technique.
Average body fat for the males (N=117) was 14.1% measured by H20 and 14.3~ as measured by Imp. The validity coeP~icient for this group was r = -.78 and the standard error of estimate (SEE) was 3.07%. The corresponding values ~or the female group (N=132 were follows: A~erage body fat from H20 = 23.5~; from Imp =
23.3%; validty coefficient, r = 0.~0; SEE = 2.879~. The results of the present study support the use of the bio-eleGtrical impedance technique as a method of assessing body composition in normal, healthy individualsO ~See Figures 10 through 15) Example II:
A study was conducted to evaluate the validity of bio-electrical impedance as an accurate assessment of body composition. Four-hundred and eighteen male and female volunteers from ~he ~niversity of 5Outhern California were used as subjects. Each subject reported to the Exercise Physiology lab at USC in a normally hydrated state. Body composition evaluation was made by hydrostatic weighing (H20) and bioelectrical impedance (~mp.~ [BioAnalogics - ~Consultant~
System] Hydrostatic weighing was done in a seated position in a 1000 gallon tank using a Chatilon autopsy scale. A minimum o~ 5 trials was made on each subject. Residual lung volume was measured utilizing the oxygen dilution technique and employing a Hewlett-Packard Nitrogen analyzer. Body fat was calculated using the formula of srozek et.al. (4.57/Density - 4.1~2 x 100%).
sio-electrical impedance was measured on each subject in a supine positionO Average body fat for the male (N=208) was 15.2%
measurèd by H20 and 1~.4% as measured by Imp. The range of body ~at for this group was 3-35%. ~he validity coefficient for this group was r = 0.76 and the standard error of estimate (SEE) was 3.34%. The corresponding values for the female group (N=211) were as follows: Average body fat from H20 = 23.~%; from Imp =
23.4%: range = 11-39%; validity coefficient, r = 0.83; SEE =
3.15%. The results of the present study support the use of the bio-electrical impedance technique as a method of assessing body composition in normal, healthy individuals.
Accordingly, the uni~ue system of the present invention provides an accurate valid measurement of human body composition consisting of fat tissue, lean tissue and body water. The inventive methodology provides a procedure for quantitative measurement o~ the conductive potential of the body, which is based on the lean tissue content of the body, in a convenient and reliable manner. Although a preferred embodiment o~ the invention has been shown and described, it will be apparent that other adaptation and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited, except as by the following claims.
This invention relates to a system for conveniently and accurately measuring anA quantitating the conductive potential of a human body which is based on a determination of lean tissue content.
Obesity has truly been declared, as of ~985 by the National Institute of Health, a stand-alone risk factor. In fact, obesity has been declared as a disease unto itself. It is now a new medical standard that obesity needs to be diagnosed and treated by a physician for the health and well-being of the general public.
A true definition of "obesity~ has been difficult to define, in that such definition is dependent upon a percent body fat determination.
Historically, "percent body fat" has been determined in research laboratories by dunking people in a hydrostatic tank to perform a hydrostatic critereon method for quantification of body fat.
Hydrodensitometry (water tank immersion) has been generally considered to be the traditional standard for body composition analysis. Despite the biological and experimental errors inherent in hydrodensitometry (Lohman, T.G., Skinfolds and Body Density and Their Relation to Body Fatness: A Review, Human Bioloav, 53~ 181-225), all other methods of analysis must be oompared to it if they are to be validated.
Another k~own method for body fat analysis is skinfold ~ 3 ~
anthropometry (calipers). However, many skilled health care practitioners have questioned this methodology for body composition analysis in that reliability is doubtful. In the hands of trained technicians, anthropometry can give errors of plus or minus nine percent (9~) when compared to densitometry ~Katch, F.I., Katch, V.L. (1980), M~asurement and Prediction Errors in Body Composition Assessment and the Search for the Perfect Equation. _esearch Ouarterly for Exercise and Support, Vol. 51, No. 1, 249-260). In general zlinical use in the hands of a variety of trained examiners wikh less than expert skill, the error in the caliper technique is presumably even greater.
Recently, body composition analyzers have been introduced that utilize a relatively new technology known as tetrapolar bio-electrical impedance.
Most importantly, through tetrapolar bio-electrical technology, the test/retest reliability has been reported as 0.5% (Lukaski, H.C., Johnson, P E., Bolonchuck, W.W., and Lykken, G.I., Assessment of Fat-Free Mass Using Bio-Electrical Impedance Measurements of the Human Body) aompared to a test/retest reliability of 3.8% ~or hydrodensitometry.
In this respect, the human body is composed basically of two components--one is lean body mass, which is composed of muscle tissue, connective tissue and bones; and the other major component is body fat. Bio-electrical impedance technology quantifies the true ratio of these components--the difference between lean body mass, which is the healthy metabolising part, and the body fat, which is the storage o~ energy in your body.
~ 3 ~
Lean body mass has about 75% water; in contrast, fat is about 3%
to 13% water. Accordingly, ~io-electrical impedance technology measures the "healthy" part of the body, which is the lean body mass.
While known tetrapolar bio-electrical technology is considered ~y many to be an advance from hydrodensitometry, both from a reliability standpoint and convenience standpoint, known systems have produced inaccurate body composition analysis in that such known systems are dependent upon a linear regression equation approach. Moreover, much of the data derived from known bio-electrical impedance techniques fails to consider biological data of specific patient groups which may deleteriously affect the accuracy of the body composition analysis.
~ ccordingly, those skilled in the art have recognized a significant need for an accurate, valid measurement approach of human body composition. The present invention provides a procedure for quantitative measurement of the conductive potential of the body in a convenient and reliable manner and then provides the means for modifying that body impedance measurement with algorithm formula equations that generate scientifically validated predictions of :human body composition analysis. The present invention fulfills these needs~
UMMARY OF THE INVENTION
The unique system of the prPsent invention provides an accurate valid measurement of human body composition consisting of fat tissue, lean tissue and body water. The inventive methodology provides a procedur~ for quantitative measurement of the conductive potential of the body, which i5 based on the lean tissue content of the body, in a convenient and reliable manner.
In more detail, the quantitative measurement in accordance with the present invention is referred to as a "bio-impedance signal. n This electrical signal, in ohms, is derived from a means for measuring body impedance component of the system. The resultant signal (three digit number, between 1 and 1000 ohms~ is then entered into a modifying means component to accurately predict the body composition of the tested individual.
The unique modifying means, in one embodied form, comprises predi~tion formulas derived from biological data inputs including a patient's height, weight, age and sex, to determine a "population prediction variable."
Thus, the unique modifying means of the inventive system interprets bio-impedance readings as "population specificn, i.e., specific impedance values are exhibited by various pre-defined populations of individuals. This specificity is related to morph-type, leanness, body water and age. In accordance with the present invention, an algorithm formula approach to prediction formulas is utilized to define an appropriate individual into a set of population specific variabl s.
~L3~8~8 Initially, the bio-impedance siynal is imputed into the modifying means along with bioloyical data. Thereafter, algorithm formulas modify the inputted signals by the appropriate correction factor. The correction factor is generally non~linear and derived from comparison with known hydrostatically derived values to produce an output which may then be conveniently displayed by indicator means so that body composition can be predicted.
It will be appreciated from the foregoing that the present invention provides an accurate and convenient system for quantifying body fat as a percentage o~ waight which is an important health management tool for patient and physician alike.
Other features and advantages of the present invention will become apparent from the following, more detailed description, taken in conjunction with the accompanying drawings, which illustrate by way of example the principles of the invention.
~ 3 ~ 8 BRIEF DESCRIPTION OF THE DRAWING
Fi~ure 1 is a perspective view of first and second prescribed locations for locating electrode sensors in accordance with one embodiment of the present invention;
Figure 2 is a perspective view of second and third prescribed locations for locating electrode sensors in accordance with one embodiment of pres~nt invention;
Figure 3 is a schematic block diagram depicting one embodied form of the inventive system for body impedance data acquisition in accordance with the present invention;
Figure 4 is a circuit diagram of a test signal generator in accordance with one embodiment of the present invention;
Figure 5 is a circuit diagram oP a power supply for the inventive system in accordance with one embodied form of the invention;
Figure 6 is a circuit diagram o~ a sensor circuit in accordance with one embodied form of the present invention;
Figure 7 is an electrical circuit diagram of a pin-out diagram of a body impedance meter in accordance with one embodiment of the present invention;
Figure 8 is a schematic in more detail of a body impedance meter in accordance with one embodiment of the pr2sent invention;
Figure 9 is a perspective view of a suitable computer in accordance with one embodiment of the present invention;
Figure 10 is a chart of tests/re-test data comparison in accordance with the present inYention:
Fi~ure 11 is a chart of inter-meter comparisons in 7~164-7 accordance wlth the present lnventlon;
Flgure 12 ls a graph whlch reflects the total sample referred to in ~xample I ln accor~ance wl~h the present invention;
Flgure 13 ls a graph whlch reflects the female component of the total ~ample referred to in Example I ln accor~ance wl~h the present lnvention;
Flgure 14 ls a yraph whlch reflects the male component of the sample referred to in Example I ln accordance wlth the present inventlon; and Flgure 15 is a chart of the data list statement for the present invention.
~ESCRIPTION OF THE PR~F~RRE~ EMBODIM~NTS
.
As shown ln the drawlngs for purposes o~ illustratlon, the present lnvention is embodied ln a unlque system for acquisitlon of body impedance date, which comprises in combination:
a) a plurallty of electrode sensors for rnountlng to prescrlbed locatlons of a patlent's body to be analyzed;
~0 b) mounting means for removably attaching said electrode sensors to a Kelvin Brldge blo-lmpedance meter system havlng ~our terminal leads;
cl means for ~enerating a current flow through said electrode sensors at a frequency of from about 40 Kilohertz to about 60 Kilohertz, thereby producing an output range of 0 to l,000 ohms;
d) means for generatlng input variables comprlsed of biologlcal patient data lncludlng helght, weight, a~e, and sex ~ 3 ~ 8 and bio-impedance signal to determine a population specific variable;
e) means for manipulating said electrical siqnals derived from said means for generating a body impedance signal with said population prediction variables f) indicator means for displaying said resultant output signal to provide quantitative measurement of conductive potential of said patient's body based on lean tissue content of said patient; and g) means for comparing said resultant signal with known scatter grams to produce an output signal representative of fat tissue, lean tissue and body water.
In accordance with the present invention, an electrical Kelvin Bridge is created by a plurality of electrodes which are removably attached to specific body areas. In more detail, prior to sensor placement, each body location is palpated and preferably cleaned with an alcohol swab to remove skin or surface oils. Thereafter, each electrode sensor is placed on a patient's body. Preferably, a conductive gel is utilized to temporaily hold the sensor in place.
ELECTRODE SENSQR LOCATIONS
(1) The first prescribed location 10 is the back side of the patient's right hand. (~Dorsal Aspect.~) Locate the ~Styloid Precess.~ (The 'bump' near the back of the wrist.) Palpate approximaely .5 to 1 inch directly across from the ~ 3 ~ 8 ~styloid Processn" (Note the slight 'depression' between the "Radius" and nUlna.'J) The First Sensor is placed across from the "Styloid Pro~ess" in the middle of the wrist. (The Sensor centar should be directly over the slight 'depression' described above.) Note: Placing the elec~rodes so they 'point' away from the body is recommended. (See Figure 1) (2) The second prescribed location 12 is behind the knuckle (joint) of the index finger of the right hand. (~Distal end of the second metacarpal.~) Palpate this area. Place the Second Sensor directly on the hand behind, but not touching, the right index finger. (See Figure 1) (3) The third prescribed location 14 is the patient's ankle at the front of the right foot. (Inbetween the nMedial~ and ~Lateral Malleoli~--the 'bumps' on the inside and outside of the ankle.) Note the slight 'depression' in this area where the ankle meets the top of the foot. Palpate here. Place the Third Sensor so that its center directly covers the slight 'depression' described above. (See Figure 2) (4) The fourth prescribed location 16 is the top of the right foot behind the joint of the great toe. (The ~Distal"
portion of the ~irst ~metatarsal.~) Palpate this area. Place the Fourth Sensor on the top o~ the right ~oot, behind, but not touching the great toe. (See Figure 2) POWER SUPPLY
The power supply for the inventive system is preferably provided by a ~ingle nine (9) volt alkaline battery (See Figures ~ fi~?~58~
3 and 5). The circuit pathways are desi~ned for sa~ety and efficiency. A momentary on and off power switch is used to c~nser~e battery life. The bio-impedance metre test life expectancy is 500 tests.
TAe design of the power supply circuit allows a test signal and a sensor circuit to operate within given parameters without ~eing dependent upon a specific hattery chanye level. Diode protection is preferably provided both at the power source and at the power input section of the printed circuit board to insure against reverse current flow.
To maintain an optimal functioning range, the system generates a 5 volt charge to power the sensor and digital functions.
To provide a reliable and viable power source, a low battery ~LED) is displayed when the current power source (9 volt battery) drops below 6.2 volts.
The power drain of the LED will consume the remaining voltage within 30 seconds. Note~ The average commercial grade 9 volt alkaline battery is char~ed at 9.2 volts.
MEANS FOR GENERATING BODY IMP~DANCE SIGNAL
Preferably one 9~volt battery operates the means for generating body impedance signal. The technology utilizes a Kelvin Bridge system with 4 terminal leads. The Sensors previously described attaches to each terminal end and is placed on the patient for correct data Impedance acquisition~
~3~ 8 OPERATION
As described, the body impedance system generates a frequency which is totally undetectable to the human body.
After chec~ing that the four electrode sensors are properly placed, the patient remains prone and still.
The on/off switch is placed in the "on" position. The Meter takes Impedance readings at a rate of 50,000 times per second. Often the Meter takes 1 to 3 seconds to stabilize while 'searching' fox the most accurate reading. Several factors such as subcutaneal fat thickness, skin thickness and body hair account for slower impedance r~adings.
TECHNICAL SPECIFICATIONS
The preferred technical specifications of the means for generating body impedance system are as follows:
a) Device test signal current - about BOO microamps nominal;
b) Device test signal frequency - about 50 KHZ nominal;
c) Input range - O to 1000 ohms;
d) Input impedance - about 10 meg ohm;
e) Accuracy - about 1%;
f) Supply current (qeiecent) - about 70 MA nominal;
g) Negative supply battery range - about 8.5 to 10 volts;
h~ Positive supply battery range - about 8.5 to 10 volts;
i) Battery polarity protection - Dual diode.
~s~ 8 SCHEMATIC DIAGRA~
The pin-out diagram illustrated in Figure 7 det~ils one embodied printed circuit board for the means for generating body impedance system.
The details of the schematic are presented in the following sections:
1) Sensor circuit; and 2~ Test signal generation.
Each of these sections will refer to block diagrams to highlight the ~xact electronic con~iguration.
SENSOR CIRCUIT
Figures 3 and 6 are blocX diagrams detailing one embodied sensor circuit o* the impedance meter. The electronic circuitry and components include the analog to digital (A to D) technology.
To obtain valid bio-impedance measurements, a true tetra - polar bridge system must be employed. The circuit in application provides a tetra-polar bridge (four lead bridge).
The sensor circuit pre~erably operates at an BOO microamp level. The sensor current combined with the test signal generation, powers the inventive system.
As outlined previously, the bio-impedance analyzer is connected to the body by ~our leads, two connected to the right hand and two to the ri~ht ~oot. The sensing current is then placed between the poles.
TEST SIGNAL GENERATION ~ 3 ~ ~ ~ 4 ~
A test signal i5 maintained through the components with a frequency of between 40 to 60 Kilohertz and pre~erably at 50 KiloHertz. The block diagram illustrated by Figures 3 and 4 de~ails the specifica~ions and current flow of the bio~impedance analyzer. The test signal configura ion is calibrated at the 500 ohms level, selected as a mid-point in the bio-impedance analyzer reading scale of 1 to 1000 ohms.
The test signal generator remains constant due to the constant voltage of 5 volts from the power supply. A constant power supply of 5 volts is critical for the re-producability of data obtained from the bio impedance analyzer. A low battery indicator calibration for 6.2 volts ensures a constant 5 volt current source.
MODIFICATION OF IMPEDANCE SIGNALS
The raw electrical signals ~rom the impedance meter are modified by a prescribed correlation factor of body density.
(BD = 1,14111-.0763 (weight) (impedance/height2).
Based on a given body density a ~range of impedance readings" is expected. This range is population specific. Thus, once body density is derived and compared to impedance, a constant is then selected for the body analysis formula.
Figure 8 represents one embodied individual progression through a population prediction formula.
a) Biological data input-1) Bio-impedance 2) Age ~3~
3) Height 4) Weight Sex b) Algorithm formula determinatio~ ~f body analysis formula constant based on body density and impedance:
e.g. If body denisty is ( 1.9 and impedance (400 then X
= 2.835 Note: X is the body analysis formula constant.
c) Population Prediction formula:
After phase one (a) and two (b) are complete, the main prediction formula which has been modified by the algorithm analyzes the data to predict body composition.
e.g. Percent fat = (4.95 / x - 4.5) Note: X is the constant ~rom the algorithm.
The inventive system preferably includes an attached micro-processor to perform the data processing tasks for body composition testing and analysis. The Computer desirable and has capacity for expandable features. (See Figure 9) Preferably the Computer is permanently mounted and cannot be removed from a transport case. A 6 volt adapter may be used to power the micro-processor.
~ 3 ~ g INDICATOR MEANS FOR DISPLAYING DATA
Preferably a Printer such as OKI-DATA 182 microline is utilized in the system. A brief explanation for operation is provided herein.
TEST PROCEDURE
Height/Weight and Proper Patient Position (1) Record patient's height and weiyht. (Height in inches, weight in pounds.) Do not use data supplied by patient.
Accurate height and weight measurements are essential for accurate results. ~emove patient's shoes for both measurements.
Also remove the sock/hose on the right foot. (The site for distal electrode sensor placement.) (2) Position the patient prone on a non-conductive surfaced table. Do not test a patient lying on a tile or carpeted ~loor.
Statis electricity contained in these surfaces interferes with accuracy. The patient must be prone to minimize interference from muscle contractions. (Antagonist muscle contractions in standing or sitting patients create inaccurate Impedance results.) (3) Arrange the patient'~ limbs so they are slightly apart, hands not touching the torso, feet not touching each other.
OPERATION CHECK LIST
a) Attach Electrode Sensors to Patient Lead Cables.
b) Remove Patient's shoes and right sock/hose.
c) Measure Patient's height.
~3~ ~$~8 d) Weigh patient.
e~ Record Patient Height and Weight on Patient Data Form.
f) Place Patient prone on table.
g) Palpate Electrode Sensor locations.
h~ Place Electrode sensors to right hand and right foot.
i) Collect Patient Impedance reading~
j) Record Impedance reading on Pa~ient Data FormO
k) Select program on the Main Menu and ENTERo 1) ENTER information needed for Patient Data Input.
m) Remove Printout from the Printer.
IILUS?RA?IVE EXAMPLES
The following specific examples will be helpful to a clearer understanding of the unique features of the present invention:
Example I:
A study was conducted to evaluate the validity of bio-electrical impedance as an accurate assessment of body composition. Two-hundred and ~orty nine male and female volunteers from the University of Southern California were used as subjects. Each subject reported to the Exercise Physiology lab at USC in a normally hydrated state. Body composition evaluation was made by hy~rostatic weighing (H20) and bioelectrical impedance ~Imp)~ Hydrostatic weighing was done in a seated position in a 1~00 gallon tank using a Chatillon autopsy scale. A minimum of 5 trials was made on each subject. Residual lung volume was measured utilizing the oxygen dilution technique and employing ~ ~lewlett-Paclcard Ni.trogen analyzer. Body fat was calculated using the formula of Brozek, et al. (~.57/Density -4.142 x 100%). Bio-electrical impedance was measured on each subject employing the sta~dard procedures ~or the technique.
Average body fat for the males (N=117) was 14.1% measured by H20 and 14.3~ as measured by Imp. The validity coeP~icient for this group was r = -.78 and the standard error of estimate (SEE) was 3.07%. The corresponding values ~or the female group (N=132 were follows: A~erage body fat from H20 = 23.5~; from Imp =
23.3%; validty coefficient, r = 0.~0; SEE = 2.879~. The results of the present study support the use of the bio-eleGtrical impedance technique as a method of assessing body composition in normal, healthy individualsO ~See Figures 10 through 15) Example II:
A study was conducted to evaluate the validity of bio-electrical impedance as an accurate assessment of body composition. Four-hundred and eighteen male and female volunteers from ~he ~niversity of 5Outhern California were used as subjects. Each subject reported to the Exercise Physiology lab at USC in a normally hydrated state. Body composition evaluation was made by hydrostatic weighing (H20) and bioelectrical impedance (~mp.~ [BioAnalogics - ~Consultant~
System] Hydrostatic weighing was done in a seated position in a 1000 gallon tank using a Chatilon autopsy scale. A minimum o~ 5 trials was made on each subject. Residual lung volume was measured utilizing the oxygen dilution technique and employing a Hewlett-Packard Nitrogen analyzer. Body fat was calculated using the formula of srozek et.al. (4.57/Density - 4.1~2 x 100%).
sio-electrical impedance was measured on each subject in a supine positionO Average body fat for the male (N=208) was 15.2%
measurèd by H20 and 1~.4% as measured by Imp. The range of body ~at for this group was 3-35%. ~he validity coefficient for this group was r = 0.76 and the standard error of estimate (SEE) was 3.34%. The corresponding values for the female group (N=211) were as follows: Average body fat from H20 = 23.~%; from Imp =
23.4%: range = 11-39%; validity coefficient, r = 0.83; SEE =
3.15%. The results of the present study support the use of the bio-electrical impedance technique as a method of assessing body composition in normal, healthy individuals.
Accordingly, the uni~ue system of the present invention provides an accurate valid measurement of human body composition consisting of fat tissue, lean tissue and body water. The inventive methodology provides a procedure for quantitative measurement o~ the conductive potential of the body, which is based on the lean tissue content of the body, in a convenient and reliable manner. Although a preferred embodiment o~ the invention has been shown and described, it will be apparent that other adaptation and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited, except as by the following claims.
Claims (7)
1. A system for acquisition for body impedance data for quantitative measurement of conductive potential of the body, the system comprising in combination:
a) a plurality of electrode sensors for mounting to a patient's body to be analyzed at prescribed locations forming a tetrapolar system;
b) mounting means for removably attaching said electrode sensors to a Kelvin Bridge bio-impedance meter system having four terminal leads;
c) means for generating a current flow through said electrode sensors at a frequency of from about 40 Kilohertz to about 60 Kilohertz, thereby producing an output range of from about 0 to 1,000 ohms;
d) means for generating input variables comprised of biological patient date including, height, weight, age and sex and bio-impedance signal derived from step (c) to determine a population specific variable;
e) means for manipulating said electrical signals derived from said means for generating a body impedance signal with said population specific variable;
f) indicator means for displaying said resultant output signal to provide quantitative measurement of conductive potential of said patient's body based on lean tissue content of said patient; and g) means for comparing said resultant signal with known controls to produce an output representative of fat tissue, lean tissue and body water.
a) a plurality of electrode sensors for mounting to a patient's body to be analyzed at prescribed locations forming a tetrapolar system;
b) mounting means for removably attaching said electrode sensors to a Kelvin Bridge bio-impedance meter system having four terminal leads;
c) means for generating a current flow through said electrode sensors at a frequency of from about 40 Kilohertz to about 60 Kilohertz, thereby producing an output range of from about 0 to 1,000 ohms;
d) means for generating input variables comprised of biological patient date including, height, weight, age and sex and bio-impedance signal derived from step (c) to determine a population specific variable;
e) means for manipulating said electrical signals derived from said means for generating a body impedance signal with said population specific variable;
f) indicator means for displaying said resultant output signal to provide quantitative measurement of conductive potential of said patient's body based on lean tissue content of said patient; and g) means for comparing said resultant signal with known controls to produce an output representative of fat tissue, lean tissue and body water.
2. The system for body impedance data acquisition as defined in Claim 1, wherein one of said electrode sensors is mounted on the dorsal aspect of the patient's right hand.
3. The system for body impedance data acquisition as defined in Claim 1, wherein one of said electrode sensors is mounted at the distal end of the second metacarpal of the patient's right hand.
4. The system for body impedance data acquisition as defined in Claim 1, wherein one of said electrode sensors is mounted in between the medial and the lateral malleoli of the patient's right foot.
5. The system for body impedance data acquisition as defined in Claim 1, wherein one of said electrode sensors is mounted at the distal portion of the first metatarsal of the patient's right foot.
6. The system for body impedance data acquisition as defined in Claim 1, wherein said means for generating a current flow operates at a frequency of about 50 Kilohertz.
7. The system for body impedance data acquisition as defined in Claim 1, and further comprising a power supply for the system.
Applications Claiming Priority (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US07/197,995 US4895163A (en) | 1988-05-24 | 1988-05-24 | System for body impedance data acquisition |
| US197,995 | 1988-05-24 | ||
| GB9515872A GB2304414B (en) | 1988-05-24 | 1995-08-02 | System for body impedance data acquisition utilizing segmental impedance and multiple frequency impedance |
| FR9509777A FR2737652A1 (en) | 1988-05-24 | 1995-08-11 | IMPROVED SYSTEM FOR ACQUIRING BODY IMPEDANCE DATA USING SEGMENTARY IMPEDANCE AND MULTI FREQUENCY IMPEDANCE |
| AU28498/95A AU2849895A (en) | 1988-05-24 | 1995-08-11 | Improved system for body impedance data aquisition utilizing segmental impedance and multiple frequency impedance |
| JP7226998A JPH0951885A (en) | 1988-05-24 | 1995-08-14 | Improved device to obtain body inpedance data, using part impedance and plurality of frequency impedances |
| NL1001109A NL1001109C1 (en) | 1988-05-24 | 1995-08-31 | Improved system for acquiring body impedance data using segmental impedance and multiple frequency impedance. |
| DE19532760A DE19532760A1 (en) | 1988-05-24 | 1995-09-05 | Body impedance data acquisition system for quantitive measurement of conductive potential of body |
| CA002157992A CA2157992A1 (en) | 1988-05-24 | 1995-09-11 | System for body impedance data acquisition and multiple frequency impedance |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1315848C true CA1315848C (en) | 1993-04-06 |
Family
ID=27570046
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000600366A Expired - Fee Related CA1315848C (en) | 1988-05-24 | 1989-05-23 | System for body impedance data acquisition |
| CA002157992A Abandoned CA2157992A1 (en) | 1988-05-24 | 1995-09-11 | System for body impedance data acquisition and multiple frequency impedance |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002157992A Abandoned CA2157992A1 (en) | 1988-05-24 | 1995-09-11 | System for body impedance data acquisition and multiple frequency impedance |
Country Status (8)
| Country | Link |
|---|---|
| US (2) | US4895163A (en) |
| EP (1) | EP0343928A3 (en) |
| JP (2) | JPH0260626A (en) |
| AU (2) | AU3464989A (en) |
| CA (2) | CA1315848C (en) |
| FR (1) | FR2737652A1 (en) |
| GB (1) | GB2304414B (en) |
| NL (1) | NL1001109C1 (en) |
Families Citing this family (140)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4895163A (en) * | 1988-05-24 | 1990-01-23 | Bio Analogics, Inc. | System for body impedance data acquisition |
| US4947862A (en) * | 1988-10-28 | 1990-08-14 | Danninger Medical Technology, Inc. | Body composition analyzer |
| US5063937A (en) * | 1990-09-12 | 1991-11-12 | Wright State University | Multiple frequency bio-impedance measurement system |
| US5203344A (en) * | 1991-01-31 | 1993-04-20 | Brigham And Women's Hospital | Method and apparatus for taking bioelectrical impedance measurements using proximally positioned electrodes |
| US5280429A (en) * | 1991-04-30 | 1994-01-18 | Xitron Technologies | Method and apparatus for displaying multi-frequency bio-impedance |
| JP2835656B2 (en) * | 1991-05-21 | 1998-12-14 | 株式会社タニタ | Bioimpedance measurement method |
| GB9113830D0 (en) * | 1991-06-27 | 1991-08-14 | Brown Brian H | Applied potential tomography |
| US5415176A (en) * | 1991-11-29 | 1995-05-16 | Tanita Corporation | Apparatus for measuring body fat |
| JP2750038B2 (en) * | 1992-03-26 | 1998-05-13 | 松下電工株式会社 | Slurry composition for fiber cement and fiber cement slurry composition |
| US5372141A (en) * | 1992-07-01 | 1994-12-13 | Body Composition Analyzers, Inc. | Body composition analyzer |
| USRE37954E1 (en) | 1992-09-23 | 2003-01-07 | Tanita Corporation | Method and apparatus for measuring body fat |
| GB9222888D0 (en) * | 1992-10-30 | 1992-12-16 | British Tech Group | Tomography |
| US5335667A (en) * | 1992-11-20 | 1994-08-09 | University Of Utah Research Foundation | Method and apparatus for determining body composition using bioelectrical impedance |
| FR2698779B1 (en) * | 1992-12-08 | 1995-01-13 | Eugedia Laboratoire | Apparatus for determining the fat mass of a patient. |
| US5579782A (en) * | 1993-08-12 | 1996-12-03 | Omron Corporation | Device to provide data as a guide to health management |
| KR0123408B1 (en) * | 1994-09-15 | 1997-11-11 | 차기철 | Method and apparatus for determining body composition using bioelectrical impedance analysis |
| JP3240401B2 (en) * | 1994-12-07 | 2001-12-17 | オムロン株式会社 | Impedance measurement device and health management guideline advice device |
| US5615689A (en) * | 1994-12-12 | 1997-04-01 | St. Luke's-Roosevelt Hospital | Method of predicting body cell mass using bioimpedance analysis |
| KR0161602B1 (en) * | 1995-06-24 | 1999-01-15 | 이재석 | Component analysis of human body and analytical method thereof using bioelectrical impedance analysis |
| AT403243B (en) * | 1995-12-12 | 1997-12-29 | Moeller Reinhard Dr | Diagnostic device |
| US20010044588A1 (en) * | 1996-02-22 | 2001-11-22 | Mault James R. | Monitoring system |
| US6243651B1 (en) * | 1996-12-17 | 2001-06-05 | Omron Corporation | Healthcare data acquisition device |
| US5788643A (en) * | 1997-04-22 | 1998-08-04 | Zymed Medical Instrumentation, Inc. | Process for monitoring patients with chronic congestive heart failure |
| EP1032441B1 (en) * | 1997-11-26 | 2004-03-03 | E-Z-Em, Inc. | Extravasation detection device |
| US6125297A (en) * | 1998-02-06 | 2000-09-26 | The United States Of America As Represented By The United States National Aeronautics And Space Administration | Body fluids monitor |
| JPH11318845A (en) * | 1998-05-14 | 1999-11-24 | Ya Man Ltd | Corporal water content estimating device |
| IL124964A (en) | 1998-06-17 | 2002-02-10 | Nimeda Ltd | Method for disclosing a physiological indication and a non-invasive diagnostic physiological monitoring system for use therewith |
| US6280396B1 (en) * | 1998-08-03 | 2001-08-28 | American Weights And Measures | Apparatus and method for measuring body composition |
| JP4046883B2 (en) * | 1999-02-09 | 2008-02-13 | 株式会社タニタ | Body fat scale and health management system |
| AUPQ113799A0 (en) * | 1999-06-22 | 1999-07-15 | University Of Queensland, The | A method and device for measuring lymphoedema |
| KR100333166B1 (en) | 1999-07-29 | 2002-04-18 | 차기철 | Useful Apparatus and Method for Analyzing Body Composition Based on Bioelectrical Impedance |
| KR100324703B1 (en) | 1999-08-09 | 2002-02-16 | 차기철 | Apparatus and Method for Analyzing Body Composition Using Novel Hand Electrodes |
| JP2001070273A (en) * | 1999-09-03 | 2001-03-21 | Tanita Corp | Method for measuring of biological electric impedance and body composition measuring device |
| EP1217942A1 (en) | 1999-09-24 | 2002-07-03 | Healthetech, Inc. | Physiological monitor and associated computation, display and communication unit |
| DE60037764T2 (en) | 1999-10-12 | 2009-01-08 | Tanita Corp. | Measuring device for a living body |
| US6292690B1 (en) * | 2000-01-12 | 2001-09-18 | Measurement Specialities Inc. | Apparatus and method for measuring bioelectric impedance |
| US6538215B2 (en) | 2000-01-13 | 2003-03-25 | Sunbeam Products, Inc. | Programmable digital scale |
| WO2001056468A2 (en) * | 2000-02-02 | 2001-08-09 | Massachusetts Institute Of Technology | Arthroscopic impedance probe to detect cartilage degeneration |
| US6482158B2 (en) | 2000-05-19 | 2002-11-19 | Healthetech, Inc. | System and method of ultrasonic mammography |
| JP3699640B2 (en) * | 2000-08-01 | 2005-09-28 | 株式会社タニタ | Body water content state determination device by multi-frequency bioimpedance measurement |
| US7228170B2 (en) * | 2000-08-14 | 2007-06-05 | Renal Research Institute, Llc | Device and method for monitoring and controlling physiologic parameters of a dialysis patient using segmental bioimpedance |
| US6615077B1 (en) * | 2000-08-14 | 2003-09-02 | Renal Research Institute, Llc | Device and method for monitoring and controlling physiologic parameters of a dialysis patient using segmental bioimpedence |
| JP4840952B2 (en) * | 2000-09-19 | 2011-12-21 | 株式会社フィジオン | Bioelectrical impedance measurement method and measurement device, and health guideline management advice device using the measurement device |
| DE20116409U1 (en) | 2000-09-30 | 2002-01-24 | Fook Tin Plastic Factory Ltd | Body fat measuring device |
| US6607387B2 (en) | 2000-10-30 | 2003-08-19 | Healthetech, Inc. | Sensor system for diagnosing dental conditions |
| US20020055857A1 (en) * | 2000-10-31 | 2002-05-09 | Mault James R. | Method of assisting individuals in lifestyle control programs conducive to good health |
| EP1205144B1 (en) * | 2000-11-06 | 2002-10-02 | Fresenius Medical Care Deutschland GmbH | A method and a device for determining the dry weight of a patient with kidney failure |
| JP4101654B2 (en) * | 2000-12-14 | 2008-06-18 | 株式会社フィジオン | Body impedance measuring device |
| US6631292B1 (en) | 2001-03-23 | 2003-10-07 | Rjl Systems, Inc. | Bio-electrical impedance analyzer |
| ITMI20010684A1 (en) * | 2001-03-30 | 2002-09-30 | Valerio Cigaina | DEVICE AND PROCEDURE FOR CHECKING THE ENTITY OF THE INTRA-ABDOMINAL FAT |
| US6718200B2 (en) * | 2001-04-10 | 2004-04-06 | Koninklijke Philips Electronics N.V. | Wearable body-fat sensor |
| US20030130595A1 (en) * | 2001-08-13 | 2003-07-10 | Mault James R. | Health improvement systems and methods |
| WO2003053239A1 (en) | 2001-12-12 | 2003-07-03 | Fresenius Medical Care Deutschland Gmbh | Determining the hydration status of a patient |
| US7218961B2 (en) * | 2002-03-19 | 2007-05-15 | Funai Electric Co., Ltd. | Percent body fat measuring apparatus using a half-wave waveform |
| US7247023B2 (en) * | 2002-06-27 | 2007-07-24 | Peplinski Daniel M | System and method for monitoring weight and nutrition |
| KR20040003255A (en) * | 2002-07-02 | 2004-01-13 | 주식회사 메디벤처 | A management-method of and management-device of fat mass which is using mobile phone |
| KR100459903B1 (en) * | 2002-07-25 | 2004-12-03 | 삼성전자주식회사 | Measurement system and electrode for measuring the impedance of small area of skin |
| AU2002951925A0 (en) * | 2002-10-09 | 2002-10-24 | Queensland University Of Technology | An Impedence Cardiography Device |
| CA2404891C (en) * | 2002-10-25 | 2003-11-18 | Nir Technologies Inc. | Method of in-vivo measurement of fat content of a body and apparatus therefor |
| US20030126593A1 (en) * | 2002-11-04 | 2003-07-03 | Mault James R. | Interactive physiological monitoring system |
| US20040181163A1 (en) * | 2003-03-13 | 2004-09-16 | Acumen | Fat analyzer |
| ES2535811T3 (en) * | 2003-03-19 | 2015-05-18 | Church Of Spiritual Technology | System to measure and indicate changes in the resistance of a living body |
| WO2004086940A2 (en) * | 2003-03-25 | 2004-10-14 | Fresenius Medical Care Holdings, Inc. | Device and method for performing electrical impedance tomography |
| JP4600914B2 (en) * | 2003-10-08 | 2010-12-22 | 株式会社タニタ | Body type identification device |
| JP4791716B2 (en) * | 2003-10-16 | 2011-10-12 | 株式会社タニタ | Maternity health management device |
| US8029454B2 (en) | 2003-11-05 | 2011-10-04 | Baxter International Inc. | High convection home hemodialysis/hemofiltration and sorbent system |
| US20050240434A1 (en) * | 2004-04-26 | 2005-10-27 | Healthport Corp. | System and method of implementing multi-level marketing of weight management products |
| US8744564B2 (en) * | 2004-06-18 | 2014-06-03 | Impedimed Limited | Oedema detection |
| US8068906B2 (en) | 2004-06-21 | 2011-11-29 | Aorora Technologies Pty Ltd | Cardiac monitoring system |
| CA2562875C (en) * | 2004-06-29 | 2014-06-17 | Fresenius Medical Care Deutschland Gmbh | A method and a device for determining the hydration and/or nutrition status of a patient |
| EP1827222A1 (en) * | 2004-11-26 | 2007-09-05 | Z-Tech (Canada) Inc. | Weighted gradient method and system for diagnosing disease |
| KR100712198B1 (en) * | 2005-02-17 | 2007-04-30 | 재단법인서울대학교산학협력재단 | Apparatus for analyzing a sleep structure according to non-constrained weight detection |
| JP4740637B2 (en) * | 2005-04-27 | 2011-08-03 | 株式会社タニタ | Trunk visceral fat measurement method and apparatus |
| JP4740636B2 (en) * | 2005-04-27 | 2011-08-03 | 株式会社タニタ | Trunk visceral fat measurement method and apparatus |
| US7638341B2 (en) * | 2005-06-09 | 2009-12-29 | The Regents Of The University Of California | Volumetric induction phase shift detection system for determining tissue water content properties |
| EP2449964B1 (en) | 2005-07-01 | 2016-08-10 | Impedimed Limited | Connector for Impedance Measurement System |
| US8781551B2 (en) * | 2005-07-01 | 2014-07-15 | Impedimed Limited | Apparatus for connecting impedance measurement apparatus to an electrode |
| AU2006265763B2 (en) | 2005-07-01 | 2012-08-09 | Impedimed Limited | Monitoring system |
| EP1741385B1 (en) * | 2005-07-07 | 2008-10-22 | Tanita Corporation | Truncal visceral/subcutaneous fat measuring method and apparatus |
| WO2007009183A1 (en) * | 2005-07-20 | 2007-01-25 | Impedance Cardiology Systems, Inc. | Index determination |
| US8099250B2 (en) * | 2005-08-02 | 2012-01-17 | Impedimed Limited | Impedance parameter values |
| BRPI0504065A (en) * | 2005-09-06 | 2007-05-22 | Ronaldo Piazzalunga | root spectral attenuation coefficient for use in endodontic foraminal locator |
| ES2476999T3 (en) | 2005-10-11 | 2014-07-15 | Impedimed Limited | Hydration Status Monitoring |
| EP2020918B1 (en) * | 2006-05-30 | 2015-05-20 | Impedimed Limited | Impedance measurements |
| AU2007291932B2 (en) * | 2006-08-28 | 2014-02-13 | Detection Systems Pty Ltd | Production line detection apparatus and method |
| US8911379B2 (en) * | 2006-09-05 | 2014-12-16 | New N.I. Medical (2011) Ltd. | Method and system for non-invasive measurement of cardiac parameters |
| CA2670293C (en) * | 2006-11-30 | 2017-01-03 | Impedimed Limited | Measurement apparatus |
| JP2008142469A (en) * | 2006-12-13 | 2008-06-26 | Tanita Corp | Living body part size measuring instrument |
| JP5400618B2 (en) * | 2007-01-15 | 2014-01-29 | インぺディメッド リミテッド | Monitoring system |
| US7910840B2 (en) * | 2007-01-31 | 2011-03-22 | Fook Tin Technologies Ltd. | Apparatus and method for determining growth status of a human subject |
| US20080183421A1 (en) * | 2007-01-31 | 2008-07-31 | Chai John Y | Apparatus and method for determining obesity-related disease risk indicators of a human subject |
| WO2008119166A1 (en) * | 2007-03-30 | 2008-10-09 | Z-Tech (Canada) Inc. | Active guarding for reduction of resistive and capactive signal loading with adjustable control of compensation level |
| EP2148613B9 (en) * | 2007-04-20 | 2014-12-10 | Impedimed Limited | Monitoring system and probe |
| JP4893515B2 (en) * | 2007-07-19 | 2012-03-07 | オムロンヘルスケア株式会社 | Body impedance measurement unit for body impedance measurement and body fat measurement device |
| CA2707419A1 (en) * | 2007-08-09 | 2009-02-12 | Impedimed Limited | Impedance measurement process |
| KR100902410B1 (en) * | 2007-09-11 | 2009-06-11 | 성 오 황 | Cardiopulmonary resuscitation apparatus and method using the same |
| WO2009036334A1 (en) * | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Adherent multi-sensor device with empathic monitoring |
| EP2200512A1 (en) * | 2007-09-14 | 2010-06-30 | Corventis, Inc. | Adherent device for respiratory monitoring and sleep disordered breathing |
| WO2009036306A1 (en) | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Adherent cardiac monitor with advanced sensing capabilities |
| US20090076397A1 (en) * | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Adherent Emergency Patient Monitor |
| US20090076343A1 (en) * | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Energy Management for Adherent Patient Monitor |
| EP2194864B1 (en) * | 2007-09-14 | 2018-08-29 | Medtronic Monitoring, Inc. | System and methods for wireless body fluid monitoring |
| WO2009036321A1 (en) * | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Adherent device for cardiac rhythm management |
| US20090076341A1 (en) * | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Adherent Athletic Monitor |
| WO2009036348A1 (en) * | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Medical device automatic start-up upon contact to patient tissue |
| WO2009036256A1 (en) * | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Injectable physiological monitoring system |
| WO2009036313A1 (en) | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Adherent device with multiple physiological sensors |
| US20090076349A1 (en) * | 2007-09-14 | 2009-03-19 | Corventis, Inc. | Adherent Multi-Sensor Device with Implantable Device Communication Capabilities |
| AU2008324750B2 (en) * | 2007-11-05 | 2014-01-16 | Impedimed Limited | Impedance determination |
| AU2008207672B2 (en) * | 2008-02-15 | 2013-10-31 | Impedimed Limited | Impedance Analysis |
| EP2257216B1 (en) * | 2008-03-12 | 2021-04-28 | Medtronic Monitoring, Inc. | Heart failure decompensation prediction based on cardiac rhythm |
| US8412317B2 (en) * | 2008-04-18 | 2013-04-02 | Corventis, Inc. | Method and apparatus to measure bioelectric impedance of patient tissue |
| US8062513B2 (en) | 2008-07-09 | 2011-11-22 | Baxter International Inc. | Dialysis system and machine having therapy prescription recall |
| US9514283B2 (en) | 2008-07-09 | 2016-12-06 | Baxter International Inc. | Dialysis system having inventory management including online dextrose mixing |
| US8168063B2 (en) | 2008-07-09 | 2012-05-01 | Baxter International Inc. | Dialysis system having filtering method for determining therapy prescriptions |
| US8057679B2 (en) | 2008-07-09 | 2011-11-15 | Baxter International Inc. | Dialysis system having trending and alert generation |
| US7981281B2 (en) * | 2008-07-09 | 2011-07-19 | Baxter International, Inc. | Dialysis system having regimen generation methodology |
| US20100191310A1 (en) * | 2008-07-29 | 2010-07-29 | Corventis, Inc. | Communication-Anchor Loop For Injectable Device |
| EP2342002A1 (en) * | 2008-10-31 | 2011-07-13 | Siemens Industry, Inc. | Manifold block for reverse osmosis systems |
| US9615766B2 (en) | 2008-11-28 | 2017-04-11 | Impedimed Limited | Impedance measurement process |
| US8386028B2 (en) * | 2009-03-24 | 2013-02-26 | Biospace Co., Ltd. | Method of analyzing body composition with measurement of voltage signals at multiple positions of body |
| US8282829B2 (en) | 2009-05-20 | 2012-10-09 | Baxter International Inc. | System and method for automated data collection of twenty-four hour ultrafiltration and other patient parameters using wired or wireless technology |
| US8926551B2 (en) * | 2009-07-07 | 2015-01-06 | Baxter Healthcare Inc. | Peritoneal dialysis therapy with large dialysis solution volumes |
| EP2295097A1 (en) | 2009-09-09 | 2011-03-16 | Fresenius Medical Care Deutschland GmbH | Method and apparatus for evaluating values representing a mass or a concentration of a substance present within the body of a patient |
| US8790259B2 (en) | 2009-10-22 | 2014-07-29 | Corventis, Inc. | Method and apparatus for remote detection and monitoring of functional chronotropic incompetence |
| US9615767B2 (en) | 2009-10-26 | 2017-04-11 | Impedimed Limited | Fluid level indicator determination |
| WO2011060497A1 (en) | 2009-11-18 | 2011-05-26 | Impedimed Limited | Signal distribution for patient-electrode measurements |
| US9451897B2 (en) * | 2009-12-14 | 2016-09-27 | Medtronic Monitoring, Inc. | Body adherent patch with electronics for physiologic monitoring |
| US8965498B2 (en) | 2010-04-05 | 2015-02-24 | Corventis, Inc. | Method and apparatus for personalized physiologic parameters |
| WO2012103576A1 (en) | 2011-02-03 | 2012-08-09 | Impedimed Limited | Tissue mass indicator determination |
| EP2790576A4 (en) | 2011-12-14 | 2015-07-08 | Intersection Medical Inc | Devices, systems and methods for determining the relative spatial change in subsurface resistivities across frequencies in tissue |
| US9591987B1 (en) | 2013-08-23 | 2017-03-14 | Rjl Systems, Inc. | Determining body composition through segmental bioelectrical impedance analysis (BIA) |
| JP6447917B2 (en) * | 2014-08-06 | 2019-01-09 | パナソニックＩｐマネジメント株式会社 | Wrist-mounted input device |
| EP3410932A1 (en) | 2016-02-02 | 2018-12-12 | The Trendlines Group Ltd. | Device for detecting body fluid balance and/or electrolyte balance |
| EP3606440A4 (en) * | 2017-04-04 | 2020-10-21 | Borut Baricevic | Method and device for determining the hydration, fitness and nutrition status of a human body |
| JP7386520B2 (en) * | 2017-12-28 | 2023-11-27 | 株式会社タニタ | Condition evaluation device, condition evaluation method, and program |
| CN108652608B (en) * | 2018-04-02 | 2020-11-24 | 芯海科技（深圳）股份有限公司 | Human body scale and method for measuring heart rate |
| CN111134674B (en) * | 2018-11-09 | 2021-10-08 | 上海交通大学 | Bioelectrical impedance tomography system based on frequency division multiplexing data compression technology |
| JP7214207B2 (en) | 2019-03-06 | 2023-01-30 | 株式会社タニタ | Internal measurement system and program |
| US11896358B2 (en) | 2020-05-11 | 2024-02-13 | Wellness Allied Inc | Device and method for dynamic skin impedance measurement and correction |
Family Cites Families (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3452743A (en) * | 1965-03-01 | 1969-07-01 | Gen Electric | Body impedance bridge |
| US3871359A (en) * | 1973-06-25 | 1975-03-18 | Interscience Technology Corp | Impedance measuring system |
| US4033336A (en) * | 1975-11-19 | 1977-07-05 | Medical Scientific International Corporation | System for sensing and recording medical information |
| JPS52149889A (en) * | 1976-06-08 | 1977-12-13 | Tokyo Shibaura Electric Co | Device for monitoring moisture in vivo |
| DE2753167A1 (en) * | 1977-11-29 | 1979-05-31 | Horst Dr Med Kief | PROCESS AND DEVICE FOR DETERMINING THE BIOENERGETIC CONDITIONS IN HUMANS OR ANIMALS IN THE FRAMEWORK OF ACUPUNCTURE DIAGNOSTICS |
| US4154114A (en) * | 1977-12-02 | 1979-05-15 | Sonometrics Systems, Inc. | Biometric measuring device |
| US4459995A (en) * | 1979-03-08 | 1984-07-17 | Lafayette R. Hubbard | Indicating device for use in a device for measuring and indicating changes in resistance of a living body |
| SE455043B (en) * | 1982-04-22 | 1988-06-20 | Karolinska Inst | DEVICE FOR MONITORING THE LIQUID BALANCE OF THE HUMAN BODY BY MEASURING THE IMPEDANCE OF THE BODY |
| JPS62169023A (en) * | 1986-01-22 | 1987-07-25 | Ya Man Ltd | Fat in body weighting meter |
| US4911175A (en) * | 1987-09-17 | 1990-03-27 | Diana Twyman | Method for measuring total body cell mass and total extracellular mass by bioelectrical resistance and reactance |
| US4895163A (en) * | 1988-05-24 | 1990-01-23 | Bio Analogics, Inc. | System for body impedance data acquisition |
| US4947862A (en) * | 1988-10-28 | 1990-08-14 | Danninger Medical Technology, Inc. | Body composition analyzer |
| US5086781A (en) * | 1989-11-14 | 1992-02-11 | Bookspan Mark A | Bioelectric apparatus for monitoring body fluid compartments |
| US5335667A (en) * | 1992-11-20 | 1994-08-09 | University Of Utah Research Foundation | Method and apparatus for determining body composition using bioelectrical impedance |
-
1988
- 1988-05-24 US US07/197,995 patent/US4895163A/en not_active Expired - Lifetime
-
1989
- 1989-05-10 AU AU34649/89A patent/AU3464989A/en not_active Abandoned
- 1989-05-23 EP EP19890305206 patent/EP0343928A3/en not_active Ceased
- 1989-05-23 JP JP1128003A patent/JPH0260626A/en active Pending
- 1989-05-23 CA CA000600366A patent/CA1315848C/en not_active Expired - Fee Related
-
1993
- 1993-06-11 US US08/076,554 patent/US5449000A/en not_active Expired - Lifetime
-
1995
- 1995-08-02 GB GB9515872A patent/GB2304414B/en not_active Expired - Fee Related
- 1995-08-11 FR FR9509777A patent/FR2737652A1/en active Pending
- 1995-08-11 AU AU28498/95A patent/AU2849895A/en not_active Abandoned
- 1995-08-14 JP JP7226998A patent/JPH0951885A/en not_active Withdrawn
- 1995-08-31 NL NL1001109A patent/NL1001109C1/en not_active IP Right Cessation
- 1995-09-11 CA CA002157992A patent/CA2157992A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0951885A (en) | 1997-02-25 |
| AU2849895A (en) | 1997-02-13 |
| FR2737652A1 (en) | 1997-02-14 |
| EP0343928A2 (en) | 1989-11-29 |
| NL1001109C1 (en) | 1997-03-03 |
| CA2157992A1 (en) | 1997-03-12 |
| US5449000A (en) | 1995-09-12 |
| GB2304414A (en) | 1997-03-19 |
| GB2304414B (en) | 1999-08-11 |
| GB9515872D0 (en) | 1995-10-04 |
| JPH0260626A (en) | 1990-03-01 |
| AU3464989A (en) | 1989-11-30 |
| US4895163A (en) | 1990-01-23 |
| EP0343928A3 (en) | 1990-12-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1315848C (en) | System for body impedance data acquisition | |
| US9149235B2 (en) | Oedema detection | |
| National Institutes of Health (US). Office of Medical Applications of Research | Bioelectrical impedance analysis in body composition measurement: National Institutes of health technology assessment conference statement, December 12-14, 1994 | |
| US9615767B2 (en) | Fluid level indicator determination | |
| US8233974B2 (en) | Method and device for measuring tissue oedema | |
| EP1262745B1 (en) | Measuring device having function for identifying a measured subject | |
| AU757258B2 (en) | Health condition judging/displaying device | |
| JPS62169023A (en) | Fat in body weighting meter | |
| JPH10185A (en) | Diagnosing device for failure in body fluid | |
| JP4099428B2 (en) | Muscle mass estimation device | |
| BhattacharJya et al. | Hand Grip Muscle Strength, Endurance and Anthropometric Parameters in Healthy Young Adults: A Cross-sectional Study. | |
| Beckmann et al. | Monitoring of body fluid in patients with chronic heart failure using Bioimpedance-Spectroscopy | |
| Turner et al. | Comparison of segmental and global bioimpedance spectroscopy errors using generalizability theory | |
| US20040260196A1 (en) | Method and apparatus for measuring local body fat by using bioelectrical impedance technology | |
| Winasis et al. | Design of integrated bioimpedance analysis and body mass index for users with special needs | |
| Yoo et al. | Body Composition Variations for Cerebral Infarction Patients Classified as Male and Female in Long-term Care Hospitals | |
| CN115916044A (en) | Edema detection | |
| JP2022135990A (en) | Method of bioimpedance vector analysis technology to evaluate local or whole body bone mineral density | |
| Mabrouk et al. | Validating Continuous Ankle Bioimpedance as a Biomarker for Fluid Status in Acute Congestive Heart Failure | |
| AU2014202075B2 (en) | Fluid level indicator determination | |
| ITMI951771A1 (en) | IMPROVED BODY IMPEDANCE DATA ACQUISITION SYSTEM USING SEGMENTAL IMPEDANCE AND MULTI-FREQUENCY IMPEDANCE | |
| Douphrate et al. | Evaluation of three near-infrared instruments for body composition assessment in an aged cardiac patient population | |
| Lozano-Nieto | Evaluation of body composition assessment by bioelectrical impedance: analysis of method errors | |
| Fox et al. | Clinically applicable methods for body fat determination | |
| Assessment | HENRY C. LUKASKl |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |