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The WallFlex Biliary RX Fully Covered Stent System RMV is indicated for indwell up to 12 months in the treatment of benign biliary strictures secondary to chronic pancreatitis.

The WallFlex Biliary RX Fully Covered Stent System RMV consists of 2 components: the implantable fully covered self-expanding metallic biliary stent (FC-SEMBS) and the Rapid Exchange (RX) delivery device. The FC-SEMBS is made out of Nitinol monofilament wire with a radiopaque platinum core, braided in a tubular mesh configuration. The stent has proximal and distal flares at each end to aid in preventing migration. The proximal flare also contains the biliary stent retrieval loop. The biliary stent is covered with a Permalume™ silicone covering along its entire length except for 2 mm on the retrieval loop end. The RX delivery device is a coaxial tube design. The exterior tube is used to constrain the biliary stent before deployment and re-constrain the biliary stent, if biliary stent repositioning is necessary, after partial deployment. The exterior tube has a clear section so that the constrained stent is visible. A yellow transition zone on the inner tube of the delivery system is visible between the stent and the blue outer sheath. There are four radiopaque (RO) markers to aid in the deployment of the stent while using fluoroscopy. There are two RO markers on the inner tube of the delivery system identifying the ends of the constrained biliary stent. Between these RO markers is an additional RO marker that indicates at what point re-constrainment is no longer possible. The fourth RO marker at the leading end of the exterior tube indicates how far the biliary stent has been deployed. There is one visual marker on the interior tube between the handles to aid in the deployment of the biliary stent. The visual marker indicates the point at which re-constrainment is no longer possible. The interior tube has a single central lumen to accommodate a 0.035 inch (0.86 mm) guidewire.

The provided text describes the WallFlex Biliary RX Fully Covered Stent System RMV, its design, nonclinical/bench studies, and a clinical study conducted to assess its safety and effectiveness.

Here's a breakdown of the acceptance criteria and study details:

1. Table of Acceptance Criteria & Reported Device Performance

The acceptance criteria are primarily derived from the "Special Controls" section and the "Summary of Nonclinical Studies" (Table 2). The reported device performance is extracted from the "Summary of Nonclinical/Bench Studies" section and the "Results" section of the clinical study.

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

• Sample Size for Clinical Study (Test Set): 127 patients for the Intent-to-Treat (ITT) cohort, and 118 patients for the Per-Protocol (PP) cohort.
• Data Provenance:
  • Country of Origin: The clinical study was a "large prospective multinational study utilizing 13 centers in 11 countries outside of the US (OUS)." Specific countries are not listed, but it indicates a broad international representation.
  • Retrospective/Prospective: The clinical study was explicitly prospective.

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

The document does not specify the number or qualifications of experts establishing ground truth for the clinical study directly. The "ground truth" for clinical outcomes (e.g., stricture resolution, stent removability, adverse events) would have been established by the clinical investigators at the 13 centers based on patient follow-up, medical records, imaging, and endoscopic findings. These would be qualified medical professionals (e.g., gastroenterologists, interventional radiologists) involved in the care of the patients and the conduct of the trial. However, no specific details on their number or specific qualifications (e.g., "radiologist with 10 years of experience") are provided within this document.

4. Adjudication Method for the Test Set

The document does not explicitly describe an adjudication method (e.g., 2+1, 3+1) for establishing clinical outcomes. Clinical outcomes would likely have been determined based on predefined criteria in the study protocol and assessed by the attending clinicians at each site. Serious adverse events (SAEs) were reported and summarized, indicating a system for tracking and categorizing these events, but not explicitly an independent adjudication panel.

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

No, an MRMC comparative effectiveness study involving human readers improving with AI vs. without AI assistance was not done. This device is a medical stent, not an AI diagnostic tool, so such a study would not be applicable. The clinical study assessed the device's performance directly in patients.

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

No, a standalone (algorithm only) study was not done. This device is a physical medical device (stent system) that requires human intervention (endoscopic placement and removal). Its performance is inherently linked to human use in a clinical setting.

7. Type of Ground Truth Used

The ground truth for the clinical study was based on clinical outcomes data from patients, including:

• Endoscopic findings (stent placement, removability, removal success)
• Patient symptoms (biliary obstructive symptoms)
• Laboratory test results (bilirubin, alkaline phosphatase levels)
• Medical records (re-interventions, recurrence, adverse events, surgical outcomes)

For the non-clinical/bench studies, the ground truth was established through engineering and laboratory test standards, specifications, and physical measurements (e.g., ISO, ASTM standards, pre-defined tolerance ranges, visual inspections, mechanical testing).

8. Sample Size for the Training Set

The document describes a single prospective clinical study acting as the primary evidence for the device's clinical performance. It does not mention a separate "training set" in the context of machine learning or AI models. This is a traditional medical device submission, not an AI/ML device.

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

As there is no "training set" in the context of an AI/ML model for this traditional medical device, this question is not applicable. The clinical study data was used to demonstrate the device's safety and effectiveness directly, not to train an algorithm.

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The Wallflex™ Enteral Colonic Stent with Anchor Lock Delivery System is indicated for palliative treatment of colonic strictures caused by malignant neoplasms and to relieve large bowel obstruction prior to colectomy in patients with malignant strictures.

The proposed Wallflex Enteral Stent with Anchor Lock Delivery System consists of 2 components: an implantable metal stent and a delivery system. The proposed stent is manufactured of Nitinol and offered in two diameters, a 25mm body with a 30mm flare, and a 22mm body with a 27mm flare. Each diameter is offered in three lengths, 6cm, 9cm, and 12cm. The proposed Anchor Lock delivery system consists of a coaxial tubing assembly that constrains the stent on the delivery catheter shaft until the stent is released by retracting the exterior tube.

The provided text describes a 510(k) summary for the Wallflex™ Enteral Colonic Stent with Anchor Lock Delivery System. It states that this is a request for an expanded indication for a device that already has existing market clearance and introduces "no new materials or design changes."

Therefore, the performance data presented in the original K042065 submission was not repeated for this K061877 submission. This means that the current document does not contain the acceptance criteria or the study that proves the device meets those criteria for the expanded indication. Instead, it relies on the predicate device's prior approval.

As such, I cannot fill in the requested table and information based solely on the provided text. The document explicitly states:

"As this is a request for an expanded indication and introduces no new materials or design changes the performance testing presented in K042065 was not repeated."

To answer the prompt fully, one would need to refer to the original K042065 submission, which is not provided here.

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The Ultraflex™ Precision™ Colonic Stent is indicated for palliative treatment of colonic strictures in the descending colon, sigmoid colon and rectum caused by malignant neoplasms and to relieve large bowel obstruction prior to colectomy in patients with malignant strictures.

The proposed Ultraflex™ Precision™ Colonic Stent System consists of a self-expanding metal stent and a delivery catheter. The proposed stent consists of Nitinol wires wound together to form a cylinder with a flared distal section. The proposed stent is mounted on a delivery catheter. The stent is compressed onto the tapered delivery catheter shaft and bound with braided nylon suture using a crochet stitch. The stent is deployed by holding the handle stationary and pulling a ring to unravel the crochet stitch.

This document describes a 510(k) submission for the Ultraflex™ Precision™ Colonic Stent System. It is an application for an expanded indication for a device that is already on the market. Therefore, the information provided focuses on the substantial equivalence to predicate devices and clinical data for the new indication, rather than detailed performance studies for the device itself.

Here's an analysis based on the provided text, addressing the requested information points where possible:

1. Table of Acceptance Criteria and Reported Device Performance

The provided text does not explicitly state specific quantitative acceptance criteria or reported device performance metrics in a tabular format. The submission relies on demonstrating substantial equivalence to existing predicate devices for its technological characteristics and presenting clinical data to support the new indication.

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

• Test Set Sample Size: Not specified in the provided text. The document mentions "Clinical data in support of the proposed indication has been collected and is presented within this submission." However, the exact number of patients or cases is not detailed here.
• Data Provenance: Not specified in the provided text (e.g., country of origin, retrospective or prospective).

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

• This information is not provided in the given text.

4. Adjudication Method for the Test Set

• This information is not provided in the given text.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

• No, an MRMC comparative effectiveness study is not mentioned or implied. The submission focuses on device performance and clinical effectiveness for a palliative indication, not on the improvement of human reader performance with AI assistance.

6. If a Standalone (Algorithm Only) Performance Study Was Done

• No, a standalone (algorithm only) performance study was not done. This device is a physical medical device (stent system), not an AI algorithm. The performance data refers to the device's functional characteristics and clinical outcomes.

7. Type of Ground Truth Used

• Given the context of a colonic stent for malignant strictures, the "ground truth" for the clinical data would likely be based on clinical observation, patient outcomes, medical diagnoses (e.g., confirmed malignant neoplasms), and potentially imaging or endoscopic confirmation of stricture palliation. The text itself does not explicitly define the "type of ground truth," but these are standard for such medical devices.

8. Sample Size for the Training Set

• This information is not applicable as this is a physical medical device, not an AI algorithm requiring a training set.

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

• This information is not applicable as this is a physical medical device, not an AI algorithm requiring a training set.

Summary based on the document:

The submission for the Ultraflex™ Precision™ Colonic Stent System asserts substantial equivalence based on:

• Technological Characteristics: The proposed device has identical materials, construction, and manufacturing processes as the currently marketed Ultraflex Precision Colonic Stent (K030769).
• Performance Data: For the new indication, "Clinical data in support of the proposed indication has been collected and is presented within this submission." The document explicitly states that performance testing from the prior K030769 submission was not repeated because there are no new materials or design changes.

The focus is on demonstrating that the new indication is safe and effective and that the device is substantially equivalent to legally marketed predicate devices (K030769 and K000281). Detailed breakdowns of clinical study methodology (sample sizes, expert qualifications, adjudication, specific metrics) are not provided in this summary document.

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