(248 days)
The Longeviti ClearFit™ Cranial Implant is designed and manufactured individually for each adult patient to correct bony voids and/or defects of the cranium.
The Longeviti ClearFit Implant is patient specific, implantable prosthetic cranioplasty plates intended to correct and/or restore bony voids and/or defects of the cranium. The implant is manufactured from polymethyl methacrylate materials and are designed using the patient's CT scan data. The devices are provided sterile and can be fixated to cranial bone using commercially available fasteners. An identical backup implant may be supplied as a courtesy to the surgeon, according to custom, but is not required. The typical maximum single plate size does not exceed a total surface area of 411 cm² and should have a nominal thickness of 4mm, not to exceed 5mm, to ensure physical integrity. Perfusion holes (also known as drainage holes) are available upon surgeon request at the time of ordering. Perfusion holes are 2mm in diameter and spaced at least 10mm apart.
The Longeviti ClearFit Cranial Implant is designed to correct bony voids and/or defects of the cranium. The provided document, a 510(k) Premarket Notification, primarily focuses on demonstrating substantial equivalence to a predicate device (Longeviti PMMA Static Cranial Implant, K170410) rather than a comprehensive study proving novel acceptance criteria.
Based on the information provided, the "acceptance criteria" are implied through various ISO and ASTM standard tests and the "study" is the battery of tests performed to fulfill these standards.
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Standard & Test) | Reported Device Performance |
|---|---|
| Biocompatibility: | All assessments were found acceptable. |
| - ISO 10993-1 (2018): Biological evaluation (risk management) | Satisfied |
| - ISO 10993-5 (2009): In vitro cytotoxicity | Satisfied |
| - USP, General Chapter & ISO 10993-11 (2017): Material mediated pyrogenicity (rabbit) | Satisfied |
| - ISO 10993-10 (2010): Irritation & skin sensitization (Guinea Pig Maximization Sensitization Test & Intracutaneous Study in Rabbits) | Satisfied |
| Sterility & Endotoxin: | All assessments were found acceptable. |
| - AAMI 11737-1: Bioburden | Satisfied |
| - ANSI ST72:2011/(R)2016: Endotoxin pyrogenicity | Satisfied |
| Material Properties (Polymethyl Methacrylate - PMMA): | All assessments were found acceptable. |
| - ASTM D7028: Glass Transition (Tg) | Satisfied |
| - ASTM D638-14: Tensile strength | Satisfied |
| - ASTM D790-15: Flexural strength | Satisfied |
| - ASTM D4812-11: Impact strength | Satisfied |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the specific sample sizes used for each of the listed tests (e.g., number of animals for biocompatibility tests, number of material samples for mechanical tests). It generally indicates that "These tests and their results contributed to the determination of Substantial Equivalence."
The data provenance is not specified. It is likely from laboratory testing conducted as part of the device development and regulatory submission process, rather than patient data. Therefore, it is prospective in the sense that the tests were conducted specifically for this submission. The country of origin for the data is not mentioned.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This type of information is not applicable to the provided document. The acceptance criteria and the "ground truth" (i.e., whether the device meets the standards) are established by the internationally recognized standards (ISO, ASTM, USP, AAMI, ANSI) themselves and assessed by qualified testing laboratories, not by a panel of clinical experts for a "test set" in the context of diagnostic accuracy.
4. Adjudication Method for the Test Set
This information is not applicable. Adjudication methods like "2+1" or "3+1" are typically used in clinical studies involving interpretation of medical images or patient outcomes by multiple experts to establish a consensus ground truth. The tests described here are laboratory and material characterization tests where the results are objectively measured against predefined standard specifications.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was Done
No, an MRMC comparative effectiveness study was not done. The document focuses on demonstrating substantial equivalence through material properties, biocompatibility, and manufacturing process similarities to a predicate device, not on assessing the diagnostic or clinical effectiveness with human readers.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was Done
No, a standalone performance study in the context of an algorithm or AI is not applicable here. The device is a physical cranial implant, not a software algorithm.
7. The Type of Ground Truth Used
The "ground truth" for the tests described is the defined specifications and requirements within the referenced ISO, ASTM, USP, AAMI, and ANSI standards. For instance, for cytotoxicity, the ground truth is the cellular response deemed acceptable by ISO 10993-5. For tensile strength, the ground truth is the specified range or minimum value per ASTM D638-14 to ensure safety and performance.
8. The Sample Size for the Training Set
This information is not applicable. The concept of a "training set" refers to data used to train machine learning algorithms. The Longeviti ClearFit Cranial Implant is a physical medical device, not an AI/ML algorithm.
9. How the Ground Truth for the Training Set Was Established
This information is not applicable for the same reasons as point 8.
§ 882.5330 Preformed nonalterable cranioplasty plate.
(a)
Identification. A preformed nonalterable cranioplasty plate is a device that is implanted in a patient to repair a skull defect and is constructed of a material, e.g., stainless steel or vitallium, that cannot be altered or reshaped at the time of surgery without changing the chemical behavior of the material.(b)
Classification. Class II (performance standards).