(30 days)
The StealthStation System, with StealthStation Cranial Software, is intended as an aid for locating anatomical structures in either open or percutaneous neurosurgical procedures. Their use is indicated for any medical condition in which the use of stereotactic surgery may be appropriate, and where reference to a rigid anatomical structure, such as the skull, can be identified relative to images of the anatomy.
This can include, but is not limited to, the following cranial procedures (including stereotactic frame-based and stereotactic frame alternatives-based procedures):
- Tumor resections
- General ventricular catheter placement
- Pediatric ventricular catheter placement
- Depth electrode, lead, and probe placement
- Cranial biopsies
The StealthStation™ Cranial Software v1.3.2 works in conjunction with an Image Guided System (IGS) which consists of clinical software, surgical instruments, a referencing system and platform/computer hardware. Image guidance, also called navigation, tracks the position of instruments in relation to the surgical anatomy and identifies this position on diagnostic or intraoperative images of the patient. During surgery, positions of specialized surgical instruments are continuously updated on these images either by optical tracking or electromagnetic tracking.
Cranial software functionality is described in terms of its feature sets which are categorized as imaging modalities, registration, planning, interfaces with medical devices, and views. Feature sets include functionality that contributes to clinical decision making and are necessary to achieve system performance.
The acceptance criteria for the StealthStation™ Cranial Software v1.3.2 are not explicitly detailed in the provided document beyond the general statement of "System Accuracy Requirements" being "Identical" to the predicate device. The performance characteristics of the predicate device, StealthStation™ Cranial Software v1.3.0, are stated as the benchmark for system accuracy.
Here's the information extracted from the document:
1. Table of Acceptance Criteria and Reported Device Performance:
| Criteria/Feature | Acceptance Criteria (based on Predicate Device K201175) | Reported Device Performance (StealthStation™ Cranial Software v1.3.2) |
|---|---|---|
| System Accuracy | Mean 3D positional error ≤ 2.0 mm | Identical; no changes made to the StealthStation™ Cranial Software that would require System Accuracy testing for v1.3.2 |
| Mean trajectory angle accuracy ≤ 2.0 degrees | ||
| All other features | Functions and performs as described for the predicate device. | All other features are identical to the predicate device. |
2. Sample size used for the test set and the data provenance:
- The document states that "Software verification testing for each requirement specification" was conducted and "Design verification was performed using the StealthStation™ System with Station™ Cranial Software v1.3.2 in laboratory."
- No specific sample size for a test set is mentioned. The testing described is software verification and design verification, not a clinical study on patient data for performance evaluation in the typical sense of AI/ML devices.
- Data provenance is not applicable or not disclosed as the document indicates "Clinical testing was not considered necessary prior to release as this is not new technology."
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable. The testing described is software and design verification rather than a clinical performance study requiring expert ground truth establishment from patient data.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable. This information is relevant for clinical studies involving multiple reviewers adjudicating findings, which was not performed.
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:
- No. An MRMC comparative effectiveness study was not performed. The device is a navigation system and not an AI-assisted diagnostic tool that would typically involve human readers.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- No. The device is a surgical navigation system, which is inherently a human-in-the-loop tool. The performance evaluation focuses on its accuracy specifications within that use case during design verification.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Not applicable. For the system accuracy, the ground truth would be precise measurements taken in a laboratory setting for the navigational accuracy, rather than clinical ground truth from patient data like pathology or outcomes.
8. The sample size for the training set:
- Not applicable. The document describes a software update for a stereotaxic instrument, not an AI/ML device that undergoes model training with a dataset.
9. How the ground truth for the training set was established:
- Not applicable. As the device is not described as an AI/ML system requiring a training set, the establishment of ground truth for such a set is not relevant.
§ 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).