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The ART (Autologous Regeneration of Tissue) Skin Harvesting System is intended for the harvesting and application of autologous, full thickness micrografts for wounds where autologous skin grafting would be appropriate.

The device is a handheld surgical skin tissue harvesting system that uses an array of coring needles to acquire full thickness skin tissue columns (hereafter referred to as "micrografts" or "microcolumns") from an appropriate healthy donor site for deposition onto an appropriate recipient treatment site (Figure 1). The procedure is minimally invasive and both the tissue acquisition (i.e., "harvest") and deposition (i.e., "scatter") processes are automatically performed by a handheld device as described below.

The device consists of three components: (1) a non-sterile, reusable handheld device; (2) a sterile, single-patient use needle cartridge containing the needle array for harvesting skin micrografts from the patient donor site; and (3) a sterile, single-patient use handheld protective sleeve to cover the handheld device (Figure 2). The handheld device uses embedded software to control the operation of the cartridge using user-activated tactile buttons and trigger (Figure 3). The sterile sleeve protects the handheld device from soilage and provides a physical barrier between the non-sterile handheld device and the patient.

The provided text describes the Medline ART Skin Harvesting System, a semi-automated device for autologous skin grafting. The document details the device's description, non-clinical/bench studies, animal wound healing studies, human factors/usability testing, and limited clinical information. It also outlines the risks to health and proposed mitigation measures.

However, the provided text does not contain explicit acceptance criteria tables or a structured comparative effectiveness study (MRMC) with human readers improving with AI vs. without AI assistance. The evaluation of the device's performance is primarily based on bench testing, animal studies, usability studies, and limited human clinical observations. The core of the evaluation focuses on the device's mechanical function, biocompatibility, sterility, software integrity, electrical safety, and its ability to facilitate wound healing compared to untreated wounds and, to some extent, traditional STSG.

Therefore, the following response compiles the available information in the format requested, making it clear where specific details (like acceptance criteria tables or MRMC study details) are not explicitly present in the provided document.

Acceptance Criteria and Device Performance Study for Medline ART Skin Harvesting System

The provided documentation focuses on a De Novo classification request for the Medline ART Skin Harvesting System. The evaluation of this device is primarily based on demonstrating its safety and effectiveness through various non-clinical (bench, animal) and limited clinical studies, rather than a quantifiable AI-driven performance assessment against explicit numerical acceptance criteria for diagnostic accuracy.

The document does not explicitly provide a formal table of "acceptance criteria" for the device's performance as if it were an AI diagnostic algorithm. Instead, it outlines performance characteristics that were tested and the results of those tests, demonstrating the device's functionality and safety. The "acceptance criteria" are implied by the successful completion of these tests and their favorable outcomes compared to controls (untreated wounds) or, in some cases, a standard of care (STSG).

Here's a synthesis of the implicit acceptance criteria and the reported device performance based on the provided text:

1. Table of Acceptance Criteria (Implicit) and Reported Device Performance

2. Sample Size and Data Provenance

• Animal Study:
  • Sample Size: 18 female Yorkshire pigs. Each pig had 6 full thickness wounds created (3 wounds per side), for a total of 108 wounds.
  • Data Provenance: Prospective animal study (porcine model). Location not specified beyond "full thickness porcine wound healing study."
• Clinical Studies (Supplemental/Confirmatory):
  • Study 1 (Early version): 25 patients (23 completed).
  • Study 2 (Early version): 12 patients (11 completed).
  • Study 3 (Final finished device - NCT05076578):
    • Group A: 10 healthy volunteers (tissue acquisition only).
    • Group B: 10 subjects with chronic wounds.
  • Data Provenance: Retrospective for Study 1 & 2 (early device version, "confirmatory information"). Prospective for Study 3 (final device, limited clinical data, "confirmatory information"). Country of origin for clinical data is not specified.

3. Number of Experts and Qualifications for Ground Truth

• Animal Study: The document refers to "scores" for erythema, edema, re-epithelialization, wound contracture, fluid/exudate, slough/necrosis, and other observations. These scores were likely assigned by trained personnel (e.g., veterinarians, researchers). Histological evaluations were also performed. No specific number or qualifications of "experts" are provided for establishing ground truth in the animal study, but the methodology implies trained observation.
• Human Factors/Usability Testing: The "experts" in this context are the users being tested.
  • Study 1: 18 nurse or doctor (HCPs) users.
  • Study 2: 7 physicians and 8 surgical podiatrists.
  • Their "ground truth" is their ability to perform tasks correctly based on training and the manual.
• Clinical Studies: For human clinical studies, "complete re-epithelialization" and "percentage area reduction (PAR)" were used as metrics of wound healing. These were likely assessed by the study investigators/clinicians. No specific number or qualifications of experts establishing ground truth for clinical outcomes are provided beyond being "investigators."

4. Adjudication Method for the Test Set

• Animal Study: Not explicitly stated, but the "internal scale" for scoring suggests a standardized, single-observer or consensus method. Numerical data and statistical comparisons are reported.
• Human Factors/Usability Testing: Success rates for tasks were recorded. No explicit multi-rater adjudication method is described.
• Clinical Studies: Clinical outcomes (re-epithelialization, PAR) were measured. No specific adjudication method across multiple evaluators is mentioned.

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

• No MRMC comparative effectiveness study was done or described. The device is a surgical instrument, not an AI-based diagnostic tool that assists human readers in interpreting images. Therefore, the concept of "effect size of how much human readers improve with AI vs. without AI assistance" is not applicable to this submission.

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

• Not applicable in the context of an AI-driven algorithm. The device itself is a semi-automated surgical tool. Its "standalone performance" is best represented by the effectiveness of the tissue harvesting and deposition process as demonstrated in bench and animal studies (e.g., ability to extract tissue to depth, deposit tissue). The human user remains "in the loop" by controlling the device activation and placement.

7. Type of Ground Truth Used

• Animal Study: Ground truth for donor and recipient site healing was established through a combination of:
  • Macroscopic Visual Scoring: (blinded or unblinded, not specified) for erythema, edema, re-epithelialization, wound contracture, fluid/exudate, slough/necrosis based on an internal scale.
  • Measurements: Wound cross-sectional diameters, circumferences, and contracture normalized to Day -2.
  • Histology: Microscopic examination of tissue samples from donor and recipient sites.
• Human Factors/Usability Testing: The ground truth for usability was the successful completion of pre-defined critical tasks performed by users following instructions.
• Clinical Studies: Ground truth for wound healing was based on:
  • Clinical Observation/Measurement: Complete re-epithelialization (visual confirmation), Percentage Area Reduction (PAR) of wounds, and observation of adverse events.

8. Sample Size for the Training Set

• Not applicable as a traditional "training set" for an AI algorithm. This is a hardware device with embedded software. The software "training" would be its development and testing phases, which are not detailed in terms of "sample size" in the same way as an AI model.
• The "development" for the device's functionality would be encompassed in the design verification, durability, and performance testing, which utilized various samples (e.g., cadaver legs for durability, porcine model for performance).

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

• Not applicable as a traditional "training set" for an AI algorithm. The "ground truth" for the device's design and software capabilities would be derived from engineering specifications and objective performance requirements validated through a rigorous design control process, including bench testing, and animal studies used to refine the device's mechanical and software functions. The provided text outlines these extensive verification and validation efforts.

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The N-SWEAT Patch is indicated for treatment of primary axillary hyperhidrosis in adults.

The N-SWEAT Patch is composed of metallic sodium on a polyester tape. This sodium bilayer is mounted to a polyethylene medical tape (adhesive backing) and covered with a release liner which is removed prior to application. The non-sterile packaged in an impermeable, argon filled, foil pouch. The packaging protects the patch during transit and storage, preventing exposure to the environment including water and air. The device is provided non-sterile and is not intended to be sterilized. A disposal kit is provided with each N-SWEAT Patch to deactivate the patch after use. The kit includes a prefilled bottle of deactivation solution, a cover paper, and a plastic bag.

The N-SWEAT patch is a non-invasive, single-use topical patch device. The N-SWEAT patch is a thermal energy-based medical device that is activated by water released from sweat glands. When applied to a dry axilla by a clinician. the sodium bilayer in the patch interacts with the water component of sweat causing the patch to generate thermal energy as well as the byproduct sodium hydroxide (NaOH) (sodium hydroxide does not contribute to the therapeutic mechanism). The rapid exothermic reaction between sweat (water) and sodium is limited by both the amount and location of the sweat. The thermal energy temporarily inactivates sweat glands leading to a reduction in sweat production. In the absence of sweat, no thermal energy is generated.

The release liner is removed immediately prior to the treatment. The reactive material is a thin layer of sodium, which interacts with the patient's sweat to deliver the treatment. The polyethylene adhesive backing on which the sodium bilayer is mounted holds the patch in place during the treatment. The argon gas provides an inert environment in the packaging to prevent the patch from oxidizing and to increase the shelf life.

The N-SWEAT Patch is applied by a clinician to the surface of dry, unabraded, intact skin of the axilla. After the skin is cleansed and dried, the release liner is removed, and the device is applied to the skin for up to 3 minutes in a physician's office or clinic. The entire device is then removed and disposed of by medical personnel. The skin is then cleansed with water to remove any sodium hydroxide residue.

The N-SWEAT Patch is indicated for the treatment of primary axillary hyperhidrosis in adults. The acceptance criteria and the study that proves the device meets these criteria are detailed below.

1. Table of Acceptance Criteria and Reported Device Performance

According to the "Special Controls" section, clinical performance testing must demonstrate: (i) reduction in hyperhidrosis using a validated measure; (ii) all adverse events; and (iii) impact of residual chemical on the skin. Non-clinical performance testing must cover: (i) thermal reactivity; (ii) total energy and energy flux; and (iii) characterization of chemical distribution. Additionally, biocompatibility, shelf-life, and comprehensive labeling are required.

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

The primary clinical study was a randomized, double-blinded, sham-controlled, pivotal study.

• Sample Size for Test Set (Clinical Study):
  • Intent-to-Treat (ITT) population: 110 randomized participants (53 N-SWEAT Treated, 57 Sham). An additional 10 participants were treated with the active device in an early safety roll-in, making the total N-SWEAT treated for safety reporting 63 (53+10).
  • Per Protocol (PP) population (primary effectiveness analysis set): 89 participants (46 N-SWEAT Treated, 43 Sham). 20 participants were excluded from the PP analysis due to confounding medications.
• Data Provenance: The study involved 11 clinical trial sites. The document does not explicitly state the country of origin, but typical FDA De Novo submissions involve studies conducted in the United States or with data accepted under FDA regulations for international studies. Given the lack of specific country mention, it is reasonable to assume it aligns with typical FDA submission practices, likely within the US.
• Retrospective or Prospective: The study was a prospective randomized, double-blinded, sham-controlled clinical trial.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications

For the clinical study, the primary endpoint (HDSS score) and secondary endpoints (GSP, QoL scores) were patient-reported outcomes or objective measurements.

• HDSS and QoL (Bother/Impact): These are self-reported patient questionnaires, not requiring expert consensus for ground truth.
• GSP (Gravimetric Sweat Production): This is an objective, quantitative measurement of sweat, also not requiring expert consensus for ground truth.
• AEs: Adverse events were recorded by the investigators (clinicians at the study sites). An Independent Data Safety Monitoring Board (DSMB) comprised of 3-5 clinical physicians with expertise in dermatology reviewed adverse events to monitor for safety risks. These experts primarily adjudicated safety, not the core effectiveness ground truth as it was based on quantitative and patient-reported metrics.

4. Adjudication Method for the Test Set

The effectiveness endpoints (HDSS, GSP, QoL) were objective or patient-reported measures and thus did not involve an adjudication method in the sense of expert review for ambiguous cases. The study was double-blinded, meaning neither the participants nor the staff administering the treatment and collecting initial data knew whether the active or sham device was used, minimizing bias in data collection. The DSMB reviewed safety data.

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

No, an MRMC comparative effectiveness study was not performed. This device is a treatment patch, and the clinical study evaluated the direct effectiveness of the patch versus a sham, rather than comparing human readers' performance with and without AI assistance in interpreting diagnostic images or data.

6. Standalone (Algorithm Only) Performance

This question is not applicable. The N-SWEAT Patch is a physical medical device that applies thermal energy, not an algorithm, AI, or software acting in a standalone diagnostic or interpretative capacity.

7. Type of Ground Truth Used

• Clinical Study (Effectiveness):
  • Patient-reported outcomes: Hyperhidrosis Disease Severity Scale (HDSS) score and Quality of Life (QoL) surveys for Bother and Impact.
  • Objective quantitative measurement: Gravimetric Sweat Production (GSP).
• pH Sub-study: Objective quantitative measurement of skin pH using a Hanna H199181 skin pH meter.
• Non-Clinical/Bench Studies: Laboratory measurements and standardized test methods (e.g., thermal characterization, sodium reactivity tests, biocompatibility tests).

8. Sample Size for the Training Set

The concept of a "training set" is not relevant here as the N-SWEAT Patch is a physical medical device, not a machine learning or AI algorithm that requires a training dataset. The clinical study was designed to evaluate the safety and effectiveness of the device itself.

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

Not applicable, as there is no training set for this type of device.

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