The L-Dex U400: A bioelectrical impedance analyzer/monitor utilizing impedance ratios that supports the measurement of extra cellular fluid volume differences between the arms to aid in the clinical assessment of unilateral lymphedema of the arm in women. This device is not intended to diagnose or predict lymphedema of an extremity.

Lymphedema Analysis PC Software – an optional PC software package that is intended to be used only with the ImpediMed L-Dex U400 analyzer/monitor for uploading data on to the PC from the L-Dex U400. processing and analyzing of bioimpedance measurements.

Device Description

The L-Dex U400 is a multi frequency bioelectrical impedance analyser. The device accurately measures current, voltage and phase angle, and calculates impedance, resistance and reactance as with the XCA. These measurements and calculations are used to estimate extra cellular fluid (ECF) allowing for the assessment of the development of unilateral Lymphedema of the arms.

The ImpediMed L-Dex U400 Extra Cellular Fluid Analyzer, like the SFB7, is a battery powered, accurate, multi frequency, bioelectrical impedance analysis instrument operating in tetra-polar mode. The device accurately measures current, voltage and phase angle, and calculates impedance, resistance and reactance.

AI/ML Overview

The provided text does not contain detailed information about specific acceptance criteria for the device or a study explicitly proving the device meets these criteria in the comprehensive manner requested. The document is primarily a 510(k) summary for the ImpediMed L-Dex U400, focusing on its intended use, device description, and technological characteristics, and stating its substantial equivalence to predicate devices.

However, based on the available information, here's what can be extracted and inferred:

1. A table of acceptance criteria and the reported device performance:

The document doesn't explicitly state quantitative acceptance criteria or detailed performance metrics from a study for the L-Dex U400. It describes the device's function and its intended use, emphasizing its ability to accurately measure current, voltage, and phase angle, and calculate impedance, resistance, and reactance to estimate extracellular fluid (ECF) for the assessment of unilateral lymphedema.

The statement "The device accurately measures current, voltage and phase angle, and calculates impedance, resistance and reactance as with the XCA" and "The ImpediMed L-Dex U400, like the SFB7, is a battery powered, accurate, multi frequency, bioelectrical impedance analysis instrument operating in tetra-polar mode" implies that its performance is considered comparable and accurate to its predicate devices.

Acceptance Criteria (Inferred from device description and intended use):

Acceptance Criteria (Inferred)	Reported Device Performance (Inferred)
Accurate measurement of current, voltage, and phase angle.	"The device accurately measures current, voltage and phase angle..."
Accurate calculation of impedance, resistance, and reactance.	"...and calculates impedance, resistance and reactance as with the XCA."
Estimation of Extra Cellular Fluid (ECF) supporting assessment of unilateral lymphedema.	"These measurements and calculations are used to estimate extra cellular fluid (ECF) allowing for the assessment of the development of unilateral Lymphedema of the arms." and "...to convert measured impedance to a corresponding estimate of extra cellular fluid ratio (extra cellular fluid index or lymphedema index referred to as L-Dex), and differences between the arms. These estimates can be used as alternatives to the current circumferential measurements and water immersion methods, to indicate trends toward the potential development of Lymphedema."
Operation as a multi-frequency bioelectrical impedance analyzer in tetra-polar mode.	"The L-Dex U400 is a multi frequency bioelectrical impedance analyser." and "The ImpediMed L-Dex U400... is a battery powered, accurate, multi frequency, bioelectrical impedance analysis instrument operating in tetra-polar mode."
Equivalent performance to predicate devices (Imp XCA and Imp SFB7).	"The device accurately measures current, voltage and phase angle, and calculates impedance, resistance and reactance as with the XCA." and "The ImpediMed L-Dex U400... like the SFB7..."
Functionality in a specified frequency range (4kHz to 1000kHz).	"...small alternating constant current of 200uA RMS at a frequency of 4kHz+ 100Hz to 1000 kHz+"
Ability to be checked with a calibration circuit for quality assurance.	"The performance of the device may be checked with the aid of a calibration circuit (supplies as an accessory) for quality assurance or servicing purposes."

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

The provided document does not mention any specific test set sample size or data provenance details (e.g., country of origin, retrospective/prospective) related to a study for the L-Dex U400's performance validation. The 510(k) summary focuses on substantial equivalence to predicate devices rather than a de novo clinical study with a specific test set.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

This information is not provided in the document.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

This information is not provided in the document.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

The document does not describe a multi-reader multi-case (MRMC) comparative effectiveness study, nor does it mention AI assistance. This device is a bioelectrical impedance analyzer, not an AI-powered diagnostic imaging tool that would typically involve human readers.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

The device itself is a standalone instrument that measures bioelectrical impedance. The Lymphedema Analysis PC Software is an optional component for data upload, processing, and analysis. Its functionality is described as "algorithm only" in the sense that it converts measured impedance into an estimate of the L-Dex index based on "simple mathematics, bioelectrical and anthropometric parameters from peer reviewed published journal articles." The document does not explicitly present a "standalone performance study" in the context of an algorithm's diagnostic accuracy against a ground truth, but rather describes its operational capabilities and the basis of its calculations.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The document states that the device's estimates "can be used as alternatives to the current circumferential measurements and water immersion methods, to indicate trends toward the potential development of Lymphedema." This implies that the accepted "ground truth" or reference methods for assessing lymphedema, which the L-Dex aims to provide an alternative for, are circumferential measurements and water immersion. The underlying validation of the mathematical models used to convert impedance to the L-Dex index relies on "peer reviewed published journal articles."

8. The sample size for the training set

The document does not mention a "training set" in the context of a machine learning model. The device's calculations are based on established bioelectrical impedance principles and parameters derived from "peer reviewed published journal articles," which would imply an empirical basis rather than a data-driven training set for an AI model.

9. How the ground truth for the training set was established

As there is no mention of a "training set" for an AI model, this information is not applicable. The basis for the device's calculations and interpretation (the L-Dex index) comes from scientific literature and established methods for studying extracellular fluid and lymphedema, which would have their own ground truth establishment methods (e.g., clinical diagnosis, volumetric measurements, expert assessment).

Summary

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KC80825
PAGE 1 OF 4
ImpediMed

OCT - 3 2008

ImpediMed Limited

ABN 65 089 705 144

Unit l 50 Parker Court Pinkenba Qld 4008

+61 (0)7 3860 3700 Tel: Freecall: | 800 638 477 Fax: +61 (0)7 3260 1225

Email: enquiries@impedimed.com www.impedimed.com

510 (k) Summary ImpediMed L-Dex U400 BIS Extra Cellular Fluid Analysis

APPLICANT INFORMATION

Company Name and address:	ImpediMed LimitedUnit150 Parker CourtPinkenba, QLD - 4008
Contact Name and numbers:	Mr Phillip AucklandChief Operations OfficerPhone: (+61) 7 3860 3700Fax: (+61) 7 3260 1225E-mail: pauckland@impedimed.com
Date of summary prepared:	August 26, 2008
DEVICE IDENTIFICATION
Trade/Proprietary name:	L-Dex U400 BIS Extra Cellular Fluid Analysis
Classification name:	Impedance Plethysmograph
Regulation number/CFR section:	21 CFR 870.2770
Product code:	DSB
Classification panel:	Cardiovascular
Device class:	Class II 000013R

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ImpediMed Limited

ABN 65 089 705 144

Unit l 50 Parker Court Pinkenba Qld 4008

+61 (0)7 3860 3700 Tel: Freecall: | 800 638 477 Fax: +61 (0)7 3260 1225

Email: enquiries@impedimed.com www.impedimed.com

PREDICATED DEVICE

Company:	ImpediMed Limited
Device name:	Imp XCA Extra Cellular Fluid Analysis
510 (K) number:	K050415
Product code:	DSB
Classification panel:	Cardiovascular
Device class:	Class II
PREDICATED DEVICE
Company:	ImpediMed Limited
Device name:	Imp SFB7 Body Composition Analyzer
510 (K) number:	K052319
Product code:	DSB
Classification panel:	Cardiovascular

Image /page/1/Picture/8 description: The image shows a series of numbers and a letter. The numbers appear to be "00014" followed by the letter "R". The text is in black and the background is white. The text is slightly blurred.

Surviving cancer without compromising lifestyle

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ImpediMed Limited

ABN 65 089 705 144

Unit I 50 Parker Court Pinkenba Qld 4008

Tel: Freecall: 1 800 638 477 +61 (0)7 3260 1225 Fax:

Email: enquiries@impedimed.com www.impedimed.com

INTENDED USE / INDICATIONS FOR USE

DEVICE DESCRIPTION

TECHNOLOGICAL CHARECTERISTICS

Bioelectrical impedance analysis measures the impedance or opposition to the flow of an electric current through the body fluids contained mainly in the lean and fat tissue. Impedance is low in lean tissue, where intracellular fluid and electrolytes are primarily contained, but high in fat tissue. Impedance is thus related to total fluid volume. The tissue and organs of the body are composed of cells surrounded by a cell membrane separates fluid inside cells called intracellular

000015R

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ImpediMed Limited

ABN 65 089 705 144

Unit l 50 Parker Court Pinkenba Qld 4008

+61 (0)7 3860 3700 Tel: Freecall: 1 800 638 477 +61 (0)7 3260 1225 Fax:

Email: enquiries@impedimed.com www.impedimed.com

fluid (ICF) from that surrounding the cells termed as extra cellular fluid (ECF) that act as conductors to the flow of current through the body.

However, the cell membrane and tissue interfaces because they are 'imperfect capacitors' act as a barrier to penetration of current at low frequencies. Thus the total impedance and phase angle of alternating current flow will be frequency dependent.

The ImpediMed L-Dex U400 is specifically designed for segmental bioelectrical impedance analysis to measure the ECF of the arms in which a small alternating constant current of 200uA RMS at a frequency of 4kHz+ 100Hz to 1000 kHz+ is passed between two current electrodes spanning the body. The voltace drop measured between a second pair of voltage-sensing electrodes is used to calculate the impedance value. The performance of the device may be checked with the aid of a calibration circuit (supplies as an accessory) for quality assurance or servicing purposes.

Bioelectrical impedance basics, simple mathematics, bioelectrical and anthropometric parameters from peer reviewed published iournal articles are used to convert measured impedance to a corresponding estimate of extra cellular fluid ratio (extra cellular fluid index or lymphedema index referred to as L-Dex), and differences between the arms. These estimates can be used as alternatives to the current circumferential measurements and water immersion methods, to indicate trends toward the potential development of Lymphedema.

annois R

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Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Mr. Phillip Auckland Chief Operations Officer ImpediMed Limited Unit 1, 50 Parker Court Pinkenba Queensland 4008 AUSTRALIA

OCT - 3 2008

Re: K080825

Trade/Device Name: ImpediMed L-Dex U400 and optional Lymphedema Analysis PC Software Regulation Number: 21 CFR §870.2770 Regulation Name: Impedance plethysmograph Regulatory Class: II Product Code: OBH Dated: August 26, 2008 Received: August 29, 2008

Dear Mr. Auckland:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. However, you are responsible to determine that the medical devices you use as components in the kit have either been determined as substantially equivalent under the premarket notification process (Section 510(k) of the act), or were legally on the market prior to May 28, 1976, the enactment date of the Medical Device Amendments. Please note: If you purchase your device components in bulk (i.e., unfinished) and further process (e.g., sterilize) you must submit a new 510(k) before including these components in your kit. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, and labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

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Page 2 -- Mr. Phillip Auckland

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on the labeling regulation, please contact the Office of Compliance at (240) 276-0115. Also, please note the regulation entitled, "Misbranding by reference to premarket notification'' (21 CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll free number (800) 638-2041 or (240) 276-3150, or at its Internet address http://www.fda.gov/cdrh.dsmamain.html.

Sincerely yours,

Hubert Leiner

Joyce M. Whang, Ph.D. Acting Director, Division of Reproductive, Abdominal, and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

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Indications for Use

510(k) Number (if known): K080825

Device Name: ImpediMed L-Dex U400

Indications for Use:

Lymphedema Analysis PC Software - an optional PC software package that is intended to be used only with the ImpediMed L-Dex U400 analyzer/monitor for uploading data on to the PC from the L-Dex U400, processing and analyzing of bioimpedance measurements.

Prescription Use (Part 21 CFR 801 Subpart D)

Over-The-Counter Use AND/OR (21 CFR 801 Subpart C)

(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE OF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Huld Leuer

(Division Sign-Off)

Divisi: : )f Reproductive, Abdomin and Rachological Devices 510(k) Number

K806625

Page 1 of 1

ﻨﻪ. ﺭﺗﺒﻪ

Regulation Number and Section

§ 870.2770 Impedance plethysmograph.

(a)
Identification. An impedance plethysmograph is a device used to estimate peripheral blood flow by measuring electrical impedance changes in a region of the body such as the arms and legs.(b)
Classification. Class II (special controls). The device, when it is a body composition analyzer which is not intended to diagnose or treat any medical condition, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 870.9.