(265 days)
Lyoplant® Onlay is indicated as a dura substitute for the repair of the dura mater.
Lyoplant Onlay is a dura substitute implant made of pure collagen that is obtained from bovine pericardium and bovine split hide. Lyoplant Onlay can be laid on the defect, or sutured depending upon surgeon preference. After implantation, it is gradually broken down enzymatically and is replaced by the body's own connective tissue. The appropriate size implant is selected depending on the area of application and is cut to size depending on the size of the defect. Lyoplant Onlay is supplied sterile and packaged as a single piece.
Here's an analysis of the provided text regarding the acceptance criteria and study for the Lyoplant® Onlay device:
1. Table of Acceptance Criteria and Reported Device Performance
The submission does not explicitly list quantitative acceptance criteria in a dedicated table format with corresponding performance results. Instead, it states that "Physical, mechanical, and biocompatibility testing have been performed on Lyoplant Onlay in accordance with the FDA guidance for industry for Dura Substitute Devices and has demonstrated the performance of Lyoplant Onlay as a dura substitute."
The tests conducted are listed as:
| Test Category | Specific Tests Conducted | Reported Performance/Outcome |
|---|---|---|
| Physical/Mechanical | Device Thickness, Tensile Strength, Suture Retention Strength, Burst Strength, Shrink Temperature Range, Surface Structure, Delamination, Chemical Characterization | The document attests that these tests "demonstrated the performance of Lyoplant Onlay as a dura substitute" and that the device possesses "adequate tear resistance and handling properties, impermeability to CSF." |
| Biocompatibility | Cytotoxicity, Maximization Sensation Study, Intracutaneous Study, Systematic Toxicity, Genotoxicity, Hemolysis, Muscle Implantation (all in accordance with ISO 10993-1) | The submission implies that these tests were passed, as it states the device has "satisfactory biocompatibility." |
| Animal Study (In Vivo) | Safety and Efficacy of Lyoplant® Onlay as a dura onlay graft in an in vivo model (comparing to Suturable DuraGen™ and autologous periosteum) | - Handling: Superior handling of Lyoplant® Onlay and Suturable DuraGen™ over periosteum. |
- Adhesion/CSF Tightness: Trend for better adhesion to dura and CSF tightness for Lyoplant® Onlay. Periosteum had highest intraoperative CSF tightness (when sutured).
- Duraplasty Time: Significantly lower for Lyoplant® Onlay (2.8±0.8 min) compared to periosteum (14.4±2.7 min).
- Tissue Integration: Fibroblast infiltration observed after 1 month for all devices; all devices completely integrated after 6 months.
- Adhesions (Graft-Cortex): More adhesions with Suturable DuraGen™ compared to Lyoplant® Onlay and periosteum. No relevant adhesions between leptomeninges and Lyoplant® Onlay.
- Lymphocytic Reaction: Comparable lymphocytic reaction of the brain for all devices. Lyoplant® Onlay and Suturable DuraGen™ showed a trend for enhanced lymphocytic reaction of brain parenchyma compared to periosteum.
- Implant Rejection: Not observed in any animals.
- Mortality: Several deaths in periosteum (n=3) and Suturable DuraGen™ (n=4) cohorts; not reported for Lyoplant® Onlay. |
2. Sample Size Used for the Test Set and Data Provenance
- Animal Study: Thirty-four (34) pigs were used for the in vivo animal study.
- Data Provenance: The animal study was conducted as an in vivo model. The country of origin for the data is not explicitly stated, but the submission is to the US FDA by a US-based company (Aesculap®, Inc. in Center Valley, PA). This suggests the testing was likely overseen by or conducted for the US entity. The data is prospective for this animal study. For the physical, mechanical, and biocompatibility tests, these are typically conducted in a laboratory setting.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- Animal Study: The document does not specify the number or qualifications of experts involved in establishing the "ground truth" for the animal study. The assessment involved "gross and histologic assessment" but does not detail who performed these or their certifications (e.g., veterinary pathologists).
4. Adjudication Method for the Test Set
- The document does not describe any specific adjudication method (e.g., 2+1, 3+1) for the assessment of the animal study results.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No MRMC comparative effectiveness study was done. The study described is an animal study comparing different dura substitute materials, not a human reader study with or without AI assistance.
6. Standalone (i.e., algorithm only without human-in-the-loop performance) Study
- Not applicable. This device is a physical dura substitute implant, not an algorithm or AI-based diagnostic tool. The performance studies are clinical (animal model) and laboratory-based, assessing material properties.
7. Type of Ground Truth Used
- Physical/Mechanical Tests: The ground truth for these tests would be the established scientific and engineering principles and the measurement standards for material properties (e.g., ISO standards for tensile strength, burst strength, etc.).
- Biocompatibility Tests: The ground truth is defined by the toxicological and biological response criteria outlined in ISO 10993-1 for biological evaluation of medical devices.
- Animal Study: The ground truth was established through direct observation (gross assessment) and microscopic examination (histologic assessment) of tissue responses and material integration in the animal model at predefined time points (1 and 6 months post-implantation). This can be considered a form of "pathology" or "biological outcomes" data in an animal model.
8. Sample Size for the Training Set
- Not applicable. This device is a physical product, not an AI or algorithm 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.
§ 882.5910 Dura substitute.
(a)
Identification. A dura substitute is a sheet or material that is used to repair the dura mater (the membrane surrounding the brain).(b)
Classification. Class II (performance standards).