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The Spiral Laminar Flow™ Vascular Arteriovenous Graft is a vascular prosthesis, which is intended for use as a subcutaneous arteriovenous conduit for vascular access during hemodialysis. ONLY trained and qualified physicians and/or surgeons, under the controlled conditions of a hospital operating theatre environment are indicated for use of this device for implantation.

The TFT Spiral Laminar Flow™ Vascular Arteriovenous Graft is to be used as an arteriovenous conduit for hemodialysis access. The graft has a specially designed section which is intended to induce spiral laminar flow. This section is designed to propagate spiral flow though the graft and into the distal circulation. TFT Spiral Laminar Flow™ Vascular Arteriovenous Graft is manufactured from a straight tubular expanded polytetrafluoroethylene (ePTFE) vascular graft. The straight graft is combined with TFT's unique SLF™ external spiral flow inducer and inducer indicator, both made from ChronoFlex® C-80A; a Biodurable Medical Grade polyurethane. The inducer indicator is a palpable ring over the proximal end of the spiral flow inducer. Its purpose is to indicate to the user where the spiral inducer segment begins since it is intended that cannulation in this segment should be avoided.

The description below is based on the provided text, which details a 510(k) submission for a medical device seeking substantial equivalence, rather than a study designed to meet specific performance acceptance criteria for an AI/ML device. Therefore, many standard fields for AI/ML study descriptions (e.g., sample size for test sets, number of experts, adjudication methods) are not applicable or cannot be extracted from this type of document.

The document describes the TFT Spiral Laminar Flow™ Vascular Arteriovenous Graft and its path to 510(k) clearance by demonstrating substantial equivalence to predicate devices, rather than meeting specific performance acceptance criteria in the format typically seen for AI/ML devices.

1. Table of Acceptance Criteria and Reported Device Performance

Given that this is a 510(k) submission for a vascular graft, the "acceptance criteria" are primarily based on demonstrating substantial equivalence to already cleared predicate devices through a comparison of technological characteristics, performance data (bench and animal testing), and materials. There aren't explicit numerical "acceptance criteria" presented in the document in the way one might see for an AI/ML diagnostic device with performance metrics (e.g., sensitivity, specificity).

Instead, the "acceptance criteria" are implicitly met by demonstrating that the device performs equivalently to the predicates across various physical, mechanical, and biological properties.

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

The primary "test set" for this submission would be considered the various experimental conditions across the bench and animal studies.

• Bench Testing (Physical & Fluid Dynamics): Details on the specific sample sizes for each physical test (e.g., how many grafts were tested for tensile strength) are not provided in the summary. For CFD and flow rig work, these are experimental setups, not human patient data.
• Animal Testing: The "Number in Each Group" is provided for each animal study (see table on Pages 5-6). For example:
  • HSAW (100): 8 mini-pigs
  • CHUM and MHI (TFT-8-006): 10 dogs (for Safety Study/Proof of principle and Performance)
  • G0003-09: 2 pigs (for Proof of principle study of 6mm ePTFE grafts)
• Data Provenance: The animal studies were conducted by various institutions (e.g., HSAW, NPIMR, CHUM, MHI, TFT). While the text doesn't explicitly state the country, the submitting company is based in Scotland, and CHUM is a common acronym for Centre hospitalier de l'Université de Montréal in Canada, suggesting international provenance for animal data. These are prospective animal studies.

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

This is a medical device (vascular graft) submission, not an AI/ML diagnostic or measurement device. Therefore, the concept of "experts used to establish ground truth" (e.g., radiologists interpreting images) is not applicable in the same way. The "ground truth" for the performance of the graft is established through objective physical measurements, detailed flow analysis, and histological/physiological assessments from animal studies, interpreted by qualified scientists and veterinarians involved in those studies. No specific number or qualifications of "experts" are cited for establishing a "ground truth" in the context of interpretation, but rather the studies themselves are the evidence.

4. Adjudication Method for the Test Set

The concept of an "adjudication method" (e.g., 2+1, 3+1 consensus) is not typically applicable to the evaluation of physical device performance or animal study outcomes in this context. The animal study outcomes would be evaluated based on predefined endpoints, measurements, and potentially histopathological analysis by veterinary pathologists.

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

This question is entirely not applicable as the submission is for a physical vascular graft, not an AI/ML diagnostic or assistive device that would involve human readers.

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

This question is entirely not applicable as the submission is for a physical vascular graft.

7. The Type of Ground Truth Used

The "ground truth" for the device's performance is established through:

• Bench Testing: Objective physical measurements against established standards (e.g., ISO7198 for tensile strength, permeability, etc.).
• Computational Fluid Dynamics (CFD) and Flow Rig Work: Mathematical models and physical simulations of fluid flow.
• Animal Studies: In vivo observation of safety (e.g., absence of adverse reactions, patency) and performance (e.g., blood flow characteristics, histological analysis of tissue response) in comparison to control devices, using established scientific and veterinary methods.

8. The Sample Size for the Training Set

This question is not applicable. There is no "training set" in the context of an AI/ML algorithm for this physical medical device submission. The "development" and "optimization" of the graft design were based on literature review, CFD, flow rig work, and various animal studies, as well as the inherent properties of the ePTFE and polyurethane materials.

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

This question is not applicable as there is no "training set" in this context. The "ground truth" for guiding the device's development (analogous to how a training set might guide an AI) was established through existing scientific literature, engineering principles of fluid dynamics, material science data for ePTFE and polyurethane, and early-stage animal studies designed for model development and proof of concept.

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The ePTFE SLF™ Spiral Vascular Grafts are indicated for use as vascular prostheses.

The device is intended for use in the bypass or reconstruction of occluded or diseased peripheral arterial blood vessels above or below the knee. Graft configurations are intended for use as arterial conduits for bypass, or reconstruction of peripheral arterial blood vessels.

The device is a vascular graft which has a specially designed section intended to induce spiral laminar flow. The grafts are manufactured from a straight tubular expanded polytetrafluoroethylene (ePTFE) vascular graft, supplied by Vascutek Ltd.

The graft includes a helical overlay of polytetrafluoroethylene (PTFE) beading, injection moulded onto the external surface of the ePTFE tube. The function of the beading is to provide reinforcement for the tube.

This device, the ePTFE SLF™ Spiral Vascular Graft, is a vascular prosthesis. The provided document is a 510(k) summary, which focuses on demonstrating substantial equivalence to predicate devices rather than proving the device meets specific acceptance criteria through a clinical study with a detailed performance table.

Therefore, many of the requested elements regarding acceptance criteria, sample sizes, expert ground truth, adjudication, and comparative effectiveness studies are not applicable in this context.

Here's an analysis based on the provided text:

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

Not Applicable. The 510(k) summary for the ePTFE SLF™ Spiral Vascular Graft does not present specific quantitative acceptance criteria or a direct performance table in the way a clinical trial report would. Instead, it asserts "substantial equivalence" to predicate devices based on technological characteristics and preclinical data.

The performance claim is qualitative:
"Bench testing and animal data demonstrated that the safety and effectiveness of the ePTFE SLF™ Spiral Vascular Grafts is equivalent to the predicate devices."

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

Not specified. The document mentions "bench testing and animal data" but does not provide details on the sample sizes, study design (retrospective/prospective), or data provenance for these tests.

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)

Not Applicable. Ground truth, in the context of clinical studies and expert review for diagnostic devices, is not relevant here as this is a medical device for implantation, and its safety and effectiveness were established through non-clinical testing.

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

Not Applicable. See point 3.

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

Not Applicable. This is an implanted medical device, not a diagnostic or AI-assisted interpretation tool. Therefore, MRMC studies and the concept of human readers improving with AI assistance are irrelevant in this context.

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

Not Applicable. See point 5.

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

For the safety and effectiveness determination, the "ground truth" was established through bench testing and animal data. This would typically involve objective measurements of physical properties (e.g., burst strength, flexibility, thrombogenicity) and biological responses in animal models (e.g., patency, tissue integration, absence of adverse reactions), compared against the predicate devices. The document does not detail specific metrics or outcomes data.

8. The sample size for the training set

Not Applicable. There is no "training set" in the context of this 510(k) submission. This is not an AI/ML device that requires a training phase.

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

Not Applicable. See point 8.

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