Search Results

Expel™ Nephroureteral Stent System with Twist-Loc™ Hub:

The Expel Nephroureteral Stents are delivered percutaneously and are intended to establish internal drainage from the ureteropelvic junction to the bladder while maintaining external access to the stent, as well as providing external drainage.

Expel™ Ureteral Stent System:

The Expel Ureteral Stent System is delivered percutaneously and is intended to establish drainage from the ureteropelvic junction to the bladder and stenting of the ureter for all patients in whom it is desirable to place a drain which does not extend externally.

The Expel Nephroureteral and Ureteral Stents are single-lumen, nonvascular intervention stents inserted using percutaneous access to provide internal and/or external drainage of the ureteropelvic junction to the bladder and stenting of the ureter. They are long-term indwelling devices not to exceed 30 days in the body.

Expel Nephroureteral Stents are available in outer diameters of 8.3 and 10.3 French, with working lengths ranging from 22 to 28 cm. They contain two pigtails each containing drainage holes. The locking, proximal pigtail forms in the renal pelvis, while the distal, concentric pigtail forms in the bladder. Drainage can occur internally (from the ureteropelvic junction to the bladder) or externally (from the bladder and ureteropelvic junction to the outside of the patient). Each pigtail has an adjacent radiopaque marker band. The distal end of the stent has a tapered tip and hydrophilic coating. The locking, proximal pigtail is activated by the Twist-Loc™ hub on the proximal end of the stent.

Expel Ureteral Stents are available in outer diameters of 6.3, 8.3, and 10.3 French, with working lengths ranging from 12 to 28 cm. The distal and proximal ends of the stent contain drainage holes within concentric pigtails. The pigtails form in opposite directions, with the proximal pigtail forming in the renal pelvis, and the distal pigtail forming in the bladder. Drainage occurs through pressure differential via gravity between the body cavities.

Each pigtail has an adjacent radiopaque marker band, and the distal end of the stent has a tapered tip and hydrophilic coating. A suture is looped through the most proximal drainage hole which allows for stent adjustment or removal during placement, and the suture is removed once placement is complete.

The Expel Nephroureteral and Ureteral Stents come with the following accessories that aid device placement.

• Cannulas
• Stabilizer
• Plug/Cap
• Pigtail Straightener

The Expel Nephroureteral and Ureteral Stents are similar in fundamental design, function, device materials, sterilization, operating principle, intended use / indication for use and fundamental technology as the predicate device, the Percuflex™ Nephroureteral Stent and Percuflex™ Ureteral Stent. The modifications from the predicate device include:

• Modified hub designs
• New stent shaft material
• Addition of radiopaque marker bands
• Extended sizes/platforms
• Modified packaging

The provided text is a 510(k) summary for the Expel™ Nephroureteral Drainage Stent With Twist-Loc Hub System and Expel™ Ureteral Drainage Stent System. It primarily focuses on demonstrating substantial equivalence to a predicate device rather than presenting detailed acceptance criteria and performance data in the typical format of a clinical study for an AI/ML device.

Therefore, many of the requested elements for an AI/ML device study are not present in this document.

Here's an analysis based on the information available in the document, and what is missing:

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

The document states: "The following bench testing was conducted for design elements and performance characteristics deemed appropriate to demonstrate equivalence to the predicate device. The Expel Nephroureteral and Ureteral Stents, including packaging, met the predetermined acceptance criteria ensuring substantial equivalence to the predicate device. No new safety or performance issues were raised during testing."

However, a specific table detailing "acceptance criteria" (e.g., minimum tensile strength, maximum leakage rate) and the "reported device performance" (actual measured values) for each test is not provided in this summary. It only lists the types of tests performed.

Types of Bench Tests Performed (reported as meeting acceptance criteria):

• Stent Dimensions OD and Working Length
• Stent Shaft Tensile Strength
• RO Marker Band Tensile Strength
• Hub to Shaft Tensile Strength
• Tip Tensile Strength
• Distal Tip Robustness
• Pigtail Recovery
• Pigtail Retention/Removal Force
• Resistance to Deformation
• Kink Resistance
• Flow Recovery Post Kinking
• Resistance to Liquid Leakage - Under Pressure and During Aspiration/Vacuum
• Stent / RO Marker Radiopacity
• MRI Compatibility
• Urine Compatibility
• Cannula / Stent Connection Force
• Cannula to Stent / Stabilizer Compatibility
• Guidewire to Stent / Cannula Compatibility
• Flexible Stiffening Cannula Hub to Shaft Tensile Strength
• Stabilizer to Flexible Stiffening Cannula Connection Force
• Coefficient of Friction
• Sterile Barrier Integrity
• Pouch Seal Strength
• Thermoformed Tray Visual
• Shelf Life
• Sterilization
• Biocompatibility

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: Not explicitly stated for each bench test. For bench testing, sample sizes typically vary depending on the specific test and statistical requirements for demonstrating equivalence/conformance.
• Data Provenance: Not applicable in the context of bench testing for a medical device. The tests are performed in a laboratory setting by the manufacturer (Boston Scientific Corporation).

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):

This information is not applicable to this type of device submission. The tests performed are physical and material property tests (bench testing), not clinical or diagnostic evaluations requiring expert adjudication of "ground truth."

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

This information is not applicable as there is no expert review or "ground truth" to adjudicate in these bench tests.

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 information is not applicable. This submission is for a physical medical device (ureteral stent), not an AI/ML-driven diagnostic or assistive technology.

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

This information is not applicable. This is not an algorithm, but a physical medical device.

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

This information is not applicable. For this type of device, "ground truth" relates to measurable physical and material properties meeting predetermined specifications, not clinical diagnostic accuracy. The "ground truth" is adherence to predefined engineering specifications and performance standards during bench testing.

8. The sample size for the training set:

This information is not applicable. This is a physical medical device, not an AI/ML model that requires training data.

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

This information is not applicable. See point 8.

In Summary:

The provided document details a 510(k) submission for a ureteral stent, focusing on demonstrating substantial equivalence through a series of bench tests. It lists the types of tests performed and states that the device met the predetermined acceptance criteria. However, it does not provide the specific numerical acceptance criteria or the measured performance results for each test. Furthermore, as this is a physical medical device and not an AI/ML product, most of the questions related to AI/ML study design, such as expert ground truth, sample sizes for test/training sets, adjudication methods, or MRMC studies, are not relevant and consequently not present in this document.

Ask a specific question about this device