(269 days)
The C-Flex Ureteral Stent Sets are intended for temporary internal drainage from the ureteropelvic junction to the bladder. Ureteral stents have been used to relieve obstruction in a variety of benign, and post-traumatic conditions. The stents may be placed using endoscopic, percutaneous, or open surgical techniques.
The 3.7 French C-Flex stents are indicated for pediatric patients.
The C-Flex Ureteral Stents are single-lumen, ureteral stents inserted using endoscopic, percutaneous, or open surgical techniques in order to provide temporary internal drainage from the ureteropelvic junction to the bladder. They are long-term indwelling devices not to exceed 6 months in the body.
The C-Flex® Ureteral Stent Set is comprised of a stent, positioner, wire guide, and catheter. The C-Flex stent is constructed from a radiopaque C-Flex material and ranges from 3.7 to 5.0 French in outer diameters with working lengths of 6.0 to 32.0 cm. The stents are available in either specified-length or multi-length stent configurations.
The sets will be supplied sterile and are intended for one-time use. The sets are packaged in a peel-open pouch with a three-year shelf life.
The request is asking for detailed information about the acceptance criteria and the study proving a device meets these criteria based on the provided text. However, the provided text is a 510(k) summary for the C-Flex Ureteral Stent Sets, which demonstrates substantial equivalence to predicate devices. It does not contain the specific, detailed quantitative acceptance criteria or the full study protocols and results in the format requested.
The document lists performance tests conducted (e.g., Retention Strength and Break Strength, Gravity Flow Rate, Radiopacity, Biocompatibility, Magnetic Resonance (MR)) and states that "All predetermined acceptance criteria were met" for some of these, but it does not specify what those acceptance criteria actually were (e.g., a specific tensile strength in Newtons, or a flow rate in mL/min).
Therefore, I cannot fulfill all parts of your request with the information given. I will provide what information is available from the text and explicitly state what is missing.
Here's the breakdown based on the provided text:
1. A table of acceptance criteria and the reported device performance
| Test Performed | Acceptance Criteria (as stated in document) | Reported Device Performance (as stated in document) |
|---|---|---|
| Retention Strength & Break Strength | "All predetermined acceptance criteria were met." (Specific criteria, e.g., minimum Newtons for retention or maximum Newtons for break, are not provided.) | * Retention strength: "shows the curl retention during proper clinical use should retain the C-Flex Ureteral Stent Set within the intended anatomy." |
- Break strength: "shows the tensile force during proper clinical use should not fracture the C-Flex Ureteral Stent Set."
- Tests were conducted following a 30-day artificial urine soak after accelerated aging to the equivalence of three years, both with and without a 30-day urine soak. |
| Gravity Flow Rate | Not explicitly stated what "acceptance criteria" were, or if this was purely a characterization test with no specific pass/fail criteria identified in this summary. | "Testing characterized the gravity flow rate of the C-Flex Ureteral Stent Set. The evaluation was conducted on the stents at time zero." (Specific flow rates are not provided.) |
| Radiopacity | Not explicitly stated what "acceptance criteria" were, or if this was purely a characterization test with no specific pass/fail criteria identified in this summary. | "Testing assessed the radiopacity of the C-Flex Ureteral Stent Set by subjecting it to a comparative fluoroscopic evaluation. Testing was conducted on the stents at time zero." (Specific qualitative or quantitative results are not provided.) |
| Biocompatibility | "All predetermined acceptance criteria were met." (Specific criteria, e.g., ISO 10993 results, are not provided.) | "Testing shows that the proposed device sets conform with the biocompatibility requirements based on its intended use." |
| Magnetic Resonance (MR) | "All predetermined acceptance criteria were met." (Specific criteria, e.g., maximum temperature rise, specific image artifact levels under defined conditions, are not provided.) | "Testing shows that the proposed device sets are MR conditional based on defined, tested conditions." |
Missing Information from the document: The quantitative or qualitative details of the "predetermined acceptance criteria" for any of the tests, and the actual performance results (e.g., specific values for retention strength, break strength, gravity flow rate, or detailed radiopacity observations). The document only provides a high-level summary that the criteria were met.
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size for Test Set: Not specified in the provided text.
- Data Provenance: Not specified in the provided text (e.g., country of origin, retrospective/prospective). These appear to be bench tests performed by the manufacturer, not clinical data.
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. The tests described are bench tests (physical and material properties,
biocompatibility, MR compatibility). They do not involve human interpretation or "ground truth" derived from expert consensus on medical images or clinical outcomes.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. As noted above, these are bench tests, not clinical studies requiring adjudication of outcomes or interpretations.
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. The device is a ureteral stent, not an AI-powered diagnostic or assistive tool for human readers. No MRMC study was mentioned or would be relevant for this type of device based on the provided summary.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. The device is a physical medical device (a ureteral stent), not an algorithm or AI system.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
Not applicable. For bench testing, the "ground truth" is typically established by engineering specifications, material standards, and validated test methods (e.g., ASTM, ISO standards). The document indicates "Biocompatibility – Testing shows that the proposed device sets conform with the biocompatibility requirements," implying adherence to a standard like ISO 10993.
8. The sample size for the training set
Not applicable. This device is a physical medical stent, not an AI/machine learning model that requires a "training set."
9. How the ground truth for the training set was established
Not applicable, as there is no training set for this type of device.
§ 876.4620 Ureteral stent.
(a)
Identification. A ureteral stent is a tube-like implanted device that is inserted into the ureter to provide ureteral rigidity and allow the passage of urine. The device may have finger-like protrusions or hooked ends to keep the tube in place. It is used in the treatment of ureteral injuries and ureteral obstruction.(b)
Classification. Class II (performance standards).