(114 days)
The WALLSTENT® Tracheobronchial Endoprosthesis is indicated for use in the treatment of tracheobronchial strictures produced by malignant neoplasms.
The WALLSTENT® Tracheobronchial Endoprosthesis is a self-expanding prosthesis constructed of biomedical superalloy and an elastomeric polymer. Smaller diameter models may utilize a radiopaque core. The prosthesis is a braided wire structure which may be covered with an elastomeric polymer in selected models. The outward radial force along with the ends of the device serve to stabilize the prosthesis after implanted. The stent's purpose is to increase or maintain the inner luminal diameter of the tracheobronchial passage. The stent is placed by means of a delivery system. The delivery system is a coaxial tubing assembly that constrains the prosthesis until it is released in a controlled manner. The release of the stent is accomplished by retracting the outer sheath. The prosthesis is packaged constrained on the delivery system ready for placement. The system is sterile and intended for single use only.
The provided text describes a 510(k) premarket notification for a medical device, the WALLSTENT® Tracheobronchial Endoprosthesis with Unistep™ Plus Delivery System. The primary purpose of this 510(k) is to introduce an alternate delivery system with a reduced profile (smaller diameter). The core endoprosthesis itself appears to be the same as the predicate device (K964121).
The study described focuses on demonstrating the substantial equivalence of this new delivery system to the existing one, not on proving the clinical efficacy or diagnostic accuracy of the stent itself.
Here's an analysis of the acceptance criteria and study data based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Stated Goal of the Study) | Reported Device Performance (as per the 510(k) summary) |
|---|---|
| Deployment forces are comparable to the current delivery systems | "The alternate delivery system can be found substantially equivalent based on the results of in vitro testing that demonstrates the deployment forces... are comparable to the current delivery systems." |
| Handling characteristics are comparable to the current delivery systems | "The alternate delivery system can be found substantially equivalent based on the results of in vitro testing that demonstrates the ...handling characteristics are comparable to the current delivery systems." |
| Design is substantially equivalent to the predicate device | "Boston Scientific Corporation has demonstrated that the WALLSTENT® Tracheobronchial Endoprosthesis with Unistep™ Plus Delivery System with reduced profile for the delivery system is substantially equivalent based on design..." |
| Test results are substantially equivalent to the predicate device | "Boston Scientific Corporation has demonstrated that the WALLSTENT® Tracheobronchial Endoprosthesis with Unistep™ Plus Delivery System with reduced profile for the delivery system is substantially equivalent based on ...test results..." |
| Indications for use are substantially equivalent to the predicate device | "Boston Scientific Corporation has demonstrated that the WALLSTENT® Tracheobronchial Endoprosthesis with Unistep™ Plus Delivery System with reduced profile for the delivery system is substantially equivalent based on ...indications for use..." |
Summary of Device Performance: The 510(k) concludes that the new delivery system is substantially equivalent to the predicate device based on in vitro testing of deployment forces and handling characteristics, as well as design and indications for use.
2. Sample Size Used for the Test Set and the Data Provenance
The document mentions "in vitro testing" but does not specify the sample size for the test set. It also does not provide information on data provenance such as country of origin or whether it was retrospective or prospective, as it's an in vitro (benchtop) study, not a clinical study involving human patients.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This information is not applicable or provided in the document. The study described is in vitro testing of mechanical properties and handling, not a study requiring expert clinical judgment or ground truth establishment in a diagnostic sense.
4. Adjudication Method for the Test Set
This information is not applicable or provided. Since the study focuses on in vitro comparisons of mechanical properties like deployment forces and handling, there would be no need for an adjudication method as seen in clinical or diagnostic studies.
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
No, an MRMC comparative effectiveness study was not done. This document describes the substantial equivalence of a medical device's delivery system, not an AI-powered diagnostic tool. Therefore, there is no AI assistance or human reader improvement to measure an effect size for.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
No, a standalone algorithm performance study was not done. This submission is for a physical medical device (stent and delivery system), not a software algorithm.
7. The Type of Ground Truth Used
The "ground truth" for this in vitro study would be the established mechanical performance and handling characteristics of the predicate delivery system. The new delivery system's performance metrics (deployment forces, handling) are compared against these known values to demonstrate "comparability." It's not clinical "ground truth" derived from pathology or outcomes.
8. The Sample Size for the Training Set
This information is not applicable or provided. This is not a machine learning or AI algorithm submission where training sets are relevant.
9. How the Ground Truth for the Training Set Was Established
This information is not applicable or provided. As above, there is no training set for a machine learning algorithm.
§ 878.3720 Tracheal prosthesis.
(a)
Identification. The tracheal prosthesis is a rigid, flexible, or expandable tubular device made of a silicone, metal, or polymeric material that is intended to be implanted to restore the structure and/or function of the trachea or trachealbronchial tree. It may be unbranched or contain one or two branches. The metal tracheal prosthesis may be uncovered or covered with a polymeric material. This device may also include a device delivery system.(b)
Classification. Class II. The special control for this device is FDA's “Guidance for the Content of Premarket Notification Submissions for Esophageal and Tracheal Prostheses.”