(102 days)
The Cranial Reducing Tubes are intended to maintain the position of instruments or devices placed using stereotactic guidance during planning and operation of neurological procedures performed in conjunction with the use of the Medtronic StealthStation System Image Guided Workstation. The devices were not tested for MR compatibility, and are not intended for use in an MRI environment.
The Medtronic Cranial Reducing Tubes (CRT) are metallic, reusable accessories that maintain the position of instruments or devices placed using stereotactic guidance during neurosurgical procedures. The CRTs have differing inner diameters (4.0 mm, 3.2 mm, and 1.7mm). The CRT inserts into the Precision Aiming Device accessory of the Medtronic StealthStation System. This is conducted in an operating room environment where navigational trajectories are determined by the StealthStation System using preoperative MR/CT scans of the patient.
Here's an analysis of the acceptance criteria and study information for the Cranial Reducing Tubes, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criterion | Reported Device Performance |
|---|---|
| Navigational Performance (Mean Positional Error) | ≤ 2.00 mm |
| Navigational Performance (Mean Trajectory Error) | ≤ 2.00° |
| Useful Life | Maintains acceptable use when exposed to cleaning, sterilization, and use conditions over the useful life of the device. |
| Repeated Drilling Exposure | Maintains acceptable use and is functional when repeatedly drilled through over the useful life of the device. |
| Usability | Satisfies the user's needs and product usability. |
| Biocompatibility (Cytotoxicity) | No reactivity (Grade 0) |
| Biocompatibility (Sensitization) | No evidence of sensitization. |
| Biocompatibility (Intracutaneous Irritation) | No evidence of irritation. |
| Biocompatibility (Acute Systemic Toxicity) | No mortality or toxicity. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not specify the sample size for the test set used for the "System Accuracy" testing. It broadly states, "The CRTs when used with compatible accessories and the StealthStation system have demonstrated accuracy..." The document also does not mention the country of origin of the data or whether the study was retrospective or prospective.
3. Number of Experts Used to Establish Ground Truth and Their Qualifications
The document does not provide information on the number of experts used to establish ground truth or their qualifications. The system accuracy testing appears to be based on physical measurements ("bench testing") rather than expert review of images or clinical outcomes.
4. Adjudication Method for the Test Set
No information is provided regarding an adjudication method. The accuracy testing appears to be a direct measurement rather than involving multiple reviewers.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No multi-reader multi-case (MRMC) comparative effectiveness study was mentioned. The device, Cranial Reducing Tubes, is a physical instrument for maintaining the position of other instruments, rather than an AI-powered diagnostic tool that would typically involve human readers. Therefore, an MRMC study comparing human readers with and without AI assistance is not applicable in this context.
6. Standalone Performance Study (Algorithm Only)
The device is a physical instrument, not an algorithm. Therefore, a standalone (algorithm only) performance study is not applicable. The listed "System Accuracy" test is essentially the standalone performance of the physical device in conjunction with the StealthStation system for its intended purpose.
7. Type of Ground Truth Used
The ground truth used for the "System Accuracy" testing appears to be objective physical measurement derived from "bench testing." This is implied by the direct measurement of positional and trajectory error. The biocompatibility tests also rely on standardized laboratory test results.
8. Sample Size for the Training Set
No information is provided regarding a training set. The device is a physical instrument for which performance is evaluated through bench testing and biocompatibility assessments, not through machine learning, which typically involves training sets.
9. How Ground Truth for the Training Set Was Established
Since there is no mention of a training set for an algorithm, the method for establishing its ground truth is not applicable/provided.
§ 882.4560 Stereotaxic instrument.
(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).