A bioclectrical impedance analyzer/monitor for use on adult human patients, utilizing impedance ratios that are displayed as an L-Dex ratio that supports the measurement of extra cellular fluid volume differences between the limbs and is presented to the clinician on an L-Dex scale as an aid to their clinical assessment of unilateral lymphedema of the arm and leg in women and the leg in men.

The device is only indicated for patients who will have or who have had lymph nodes, from the axillary and pelvic regions, either removed, damaged or irradiated.

The device is not intended to diagnose or predict lymphedema of the 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 ExtraCellular Fluid Analyzer like its predicate is a multi-frequency bioelectrical impedance analyzer. It is a non-invasive, battery powered extracellular fluid status analyzer.

The L-Dex® U400 accurately measures current, voltage and phase angle, calculates impedance, resistance and reactance as with its predicate. These measurements and calculations are used to estimate extracellular fluid (ECF) allowing for aiding in the assessment of the development of unilateral Lymphedema of the limbs.

AI/ML Overview

The provided text does not contain detailed information about specific acceptance criteria or a dedicated study proving the device meets those criteria. The submission is a 510(k) premarket notification primarily focused on demonstrating substantial equivalence to a predicate device for expanded indications for use.

Here's an analysis based on the available text:

1. Table of Acceptance Criteria and Reported Device Performance:

The document does not specify quantitative acceptance criteria or a direct performance table for the L-Dex® U400 ExtraCellular Fluid Analyzer. Instead, it relies on demonstrating that the device is substantially equivalent to its predicate (L-Dex® U400 ExtraCellular Fluid Analyzer, K080825) in terms of design, construction, hardware, software, operational features, and safety features.

The core performance claim is its ability to "accurately measure current, voltage and phase angle, calculate impedance, resistance and reactance" and use these to "estimate extracellular fluid (ECF) allowing for aiding in the assessment of the development of unilateral Lymphedema of the limbs." However, specific numerical performance metrics (e.g., accuracy, sensitivity, specificity, or inter-rater reliability values) are not provided in this summary.

2. Sample Size Used for the Test Set and Data Provenance:

The document states, "Clinical Performance data in support of the expanded indications for use is included within this submission." However, it does not provide any details about:

The sample size used for any clinical test set.
The data provenance (e.g., country of origin, retrospective or prospective nature of the data).
The type of study design for this clinical performance data.

3. Number of Experts Used to Establish Ground Truth and Qualifications:

The document does not mention using experts to establish ground truth for a test set. This type of detail would typically be found in a more comprehensive clinical study report, which is not included in this 510(k) summary.

4. Adjudication Method for the Test Set:

Since there is no mention of experts or a test set requiring adjudication, there is no information on the adjudication method.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

The document does not mention a multi-reader multi-case (MRMC) comparative effectiveness study or any effect size related to human readers improving with AI assistance. The device is described as "a bioelectrical impedance analyzer/monitor," which suggests a direct measurement device rather than an AI-assisted diagnostic tool for human readers.

6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study:

The document focuses on the device's ability to measure and calculate, with the output (L-Dex ratio) being presented to a clinician "as an aid to their clinical assessment." This implies a standalone performance of the device's measurements and calculations. However, no specific standalone performance metrics (like accuracy against a gold standard for ECF volume differences) are provided in this summary. The "clinical performance data" mentioned must have related to this, but the details are omitted.

7. Type of Ground Truth Used:

The document does not explicitly state the type of ground truth used for any clinical performance data. Given the device's function to aid in the assessment of lymphedema, potential ground truths could include:

Physical measurements (e.g., circumference measurements)
Diagnosis by a specialist physician (e.g., lymphedema specialist)
Imaging techniques
Pathology (though less likely for lymphedema diagnosis in this context)
Outcomes data

However, none of these are confirmed in the provided text.

8. Sample Size for the Training Set:

The document does not mention a training set sample size. This information would typically be relevant for machine learning algorithms, and while the device uses "bioelectrical impedance analyzer/monitor" it is not explicitly stated to be an AI/ML device in the modern sense. It calculates impedance ratios, which implies a pre-defined algorithm rather than one that learns from a training set.

9. How the Ground Truth for the Training Set Was Established:

Since no training set is mentioned, there is no information on how its ground truth was established.

In summary:

This 510(k) summary focuses on demonstrating substantial equivalence to a predicate device for expanded indications, rather than providing detailed acceptance criteria and supporting clinical study results with specific metrics, sample sizes, and ground truth methodologies. The core argument for safety and effectiveness relies on the L-Dex® U400 being identical in design and function to a previously cleared device. Information regarding specific clinical performance data is noted as being included in the full submission, but not detailed in this summary.

Summary

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K100811
PAGE 1 OF 3
NOV - 4 2011

L-Dex® U400 ExtraCellular Fluid Analyzer

510(k) Traditional Premarket Notification Summary

Device Trade or Proprietary Name:	L-Dex® U400 ExtraCellular Fluid Analyzer
Common / Classification Name:	Impedance Plethysmograph
Class:	II
Regulation Number:	870.2770
Panel:	Cardiovascular
Product Code:	DSB

Labeling:

Federal (United States) Law restricts this device to sale by or on the order of a physician or licensed healthcare professional.

Predicate Device for Substantial Equivalence Comparison:

The L-Dex® U400 ExtraCellular Fluid Analyzer, also referred to as the L-Dex U400 in the rest of this document, is claimed to be substantially equivalent to the following currently marketed Predicate Device and currently being marketed by ImpediMed Limited:

Manufacturer	Device Name	510-KNumber	Decision Date
ImpediMedLimited	L-Dex® U400 ExtraCellular FluidAnalyzer	K080825	Oct. 03, 2008

Device Description:

This premarket submission is to expand the previously cleared Indications for Use/Intended Use in the predicate device to include legs in women and men in addition to the predicate device clearance for arms in women, and clarify that it is for use on adult human patients.

The L-Dex® U400 ExtraCellular Fluid Analyzer like its predicate is a multi-frequency bioelectrical impedance analyzer. It is a non-invasive, battery powered extracellular fluid status analyzer.

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2 OF 3

Indications for Use/Intended Use:

A bioelectrical impedance analyzer/monitor for use on adult human patients, utilizing impedance ratios that are displayed as an L-Dex ratio that supports the measurement of extra cellular fluid volume differences between the limbs and is presented to the clinician on an L-Dex scale as an aid to their clinical assessment of unilateral lymphedema of the arm and leg in women and the leg in men.

The device is only indicated for patients who will have or who have had lymph nodes, from the axillary and pelvic regions, either removed, damaged or irradiated. The device is not intended to diagnose or predict lymphedema of the extremity.

Contraindications for Use:

Patients with active implanted medical devices, pregnant patients (unless under the guidance of a medical specialist), and patients undergoing external defibrillation.

Patients with allergies to electrode hydrogel, skin sensitivities to electrode hydrogel and skin breakdown in areas where the L-Dex electrode placement is required.

This device is contraindicated for use on compromised skin surfaces primarily due to the adherence of the EKG type electrodes used.

Clinical Performance Data:

Clinical Performance data in support of the expanded indications for use is included within this submission.

Rationale for Substantial Equivalence:

1. The L-Dex® U400 employs the same patient interface design as the predicate device.
1. The hardware and software of the L-Dex® U400 is identical in design, construction and manufacturer as the predicate device.
1. The operational features of the L-Dex® U400 are the same as those of the predicate device.
1. The safety features of the L-Dex® U400 are the same as those of the predicate device.

Therefore, in summary, the L-Dex® U400 ExtraCellular Fluid Status Analyzer is substantially equivalent to the predicate device.

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Safety and Effectiveness

The L-Dex® U400 ExtraCellular Fluid Analyzer complies with the electrical standards for Safety and Electro Magnetic Compatibility / Immunity (EMC / EMI) in accordance with the International Standards IEC 60101-1 and IEC 60601-1-2. This testing to the low voltage directive and to emissions / immunity requirements for EMC/EMI requirements reasonably assures the device is safe when used as directed for its prescribed intended use.

The L-Dex® U400 ExtraCellular Fluid Status Analyzer does not raise any new issues of safety, effectiveness or performance of the device when compared to the existing predicate device.

Conclusions:

The data submitted in this 510(k) Premarket Notification, for the L-Dex® U400

ExtraCellular Fluid Status Analyzer demonstrates that this product is substantially

equivalent with respect to the indications for use, operating principles, operational features

and safety features to the legally marketed predicate device. With the information

provided, the safety and effectiveness of the product can be reasonably assured, and we

believe that this device clearly meets the requirements for a "Substantial Equivalence"

decision in accordance with the 510(k) guidelines.

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Image /page/3/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a stylized eagle with its wings spread, enclosed within a circle. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" is arranged around the upper portion of the circle.

Food and Drug Administration 10903 New Hampshire Avenue Document Mail Center - WO66-G609 Silver Spring, MD 20993-0002

NOV - 4 2011

ImpediMed Limited % Mr. Alden Kav Vice President Quality & Regulatory ImpediMed Limited 5959 Cornerstone Court West, Suite 100 SAN DIEGO CA 92121 ·

Re: K100811

Trade/Device Name: L-Dex® U400 ExtraCellular Fluid Analyzer Regulation Number: 21 CFR& 870.2770 Regulation Name: Impedance plethysmograph Regulatory Class: II Product Code: OBH Dated: May 16, 2011 Received: May 18, 2011

Dear Mr. Kay:

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 (for the indications for use stated in the enclosure) 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) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

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.

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); medical device reporting of medical device-related

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adverse events) (21 CFR 803); 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.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please go to http://www.fda.gov/AboutFDA/CentersOffices/CDRH/CDRHOffices/ucm115809.htm for the Center for Devices and Radiological Health's (CDRH's) Office of Compliance. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

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 (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/Resourcesfor You/Industry/default.htm.

Sincerely yours,

Hubert Lemmer MD

Herbert P. Lerner, M.D., Director (Acting) Division of Reproductive, Gastro-Renal and Urological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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K100811 510(k) Number: L-Dex® U400 ExtraCellular Fluid Analyzer Device Name:

Indications for Use/Intended Use:

The device is only indicated for patients who will have or who have had lymph nodes, from the axillary and pelvic regions, either removed, damaged or irradiated.

The device is not intended to diagnose or predict lymphedema of the extremity.

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use _____ (Per 21 CFR 801.109)

Hulut

(Division Sign-Off)
Division of Reproductive, Gastro-Renal, and
Urological Devices
K100811
510(k) Number

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.