(226 days)
The StealthStation™ System, with Station™ 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 user should consult the "Navigational Accuracy" section of the User Manual to assess if the accuracy of the system is suitable for their needs.
The StealthStation™ System is intended as an aid for precisely locating anatomical structures in either open or percutaneous procedures. The StealthStation™ System 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, a long bone, or vertebra, can be identified relative to a CT or MR based model, fluoroscopy images, or digitized landmarks of the anatomy.
The StealthStation™ S8 System, with StealthStation™ Cranial v1.0.0 software helps guide surgeons during cranial surgical procedures such as biopsies, tumor resections, and shunt and lead placements. The StealthStation™ Cranial v1.0.0 software (cranial software) works in conjunction with an Image Guided System (IGS) which consists of clinical software, surgical instruments, a referencing system and platform/computer hardware. Image quidance, 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.
Here's a breakdown of the acceptance criteria and study information for the StealthStation™ S8 System with StealthStation™ Cranial software, based on the provided document:
1. Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| 3D Positional Accuracy: Mean Error ≤ 2.0 mm | Optical Localization: Mean Error = 1.45 mm |
| EM Localization: Mean Error = 0.84 mm | |
| Mechanical Localization: Mean Error = 1.48 mm | |
| Trajectory Angle Accuracy: Mean Error ≤ 2.0 degrees | Optical Localization: Mean Error = 0.60 degrees |
| EM Localization: Mean Error = 0.47 degrees | |
| Mechanical Localization: Mean Error = 0.39 degrees |
2. Sample Size and Data Provenance for Test Set
- Sample Size: The document does not explicitly state the numerical sample size for the test set used in the accuracy validation. It mentions "anatomically representative phantoms" and "a subset of system components and features that represent the worst-case combinations."
- Data Provenance: The testing was conducted in "laboratory and simulated use settings" and involved "anatomically representative phantoms." This indicates that the data is synthetic/simulated (phantom-based) rather than from human subjects. The country of origin is not explicitly stated, but the submission is to the U.S. FDA, implying potentially U.S.-based testing or at least testing compliant with U.S. regulations. The study is prospective in nature, as it's a validation study for a new device.
3. Number and Qualifications of Experts for Test Set Ground Truth
The document does not provide information on the number or qualifications of experts used to establish ground truth for the test set. Given the use of "anatomically representative phantoms," the ground truth likely refers to precisely engineered and measured targets within these phantoms, rather than clinical consensus among medical experts.
4. Adjudication Method for Test Set
The document does not specify an adjudication method. For phantom-based accuracy testing, adjudication by human experts is typically not required as the ground truth is pre-defined by the phantom design and precision measurements.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study was done. The document states, "Clinical testing was not considered necessary prior to release as this is not new technology." This indicates that the study focused on the device's standalone performance and equivalence to existing technology, not on its comparative effectiveness when used by human readers with and without AI assistance.
6. Standalone (Algorithm Only) Performance Study
Yes, a standalone (algorithm only) performance study was done. The entire "Discussion of the Performance Testing" section details the accuracy validation of the device itself (StealthStation™ S8 System with StealthStation™ Cranial Software) using phantoms. This is fundamentally a standalone evaluation of the system's ability to achieve positional and trajectory accuracy.
7. Type of Ground Truth Used
The ground truth used was based on precisely measured targets within anatomically representative phantoms. This is a form of engineered or physical ground truth, not clinical ground truth derived from pathology, expert consensus, or outcomes data, as no clinical testing was performed.
8. Sample Size for Training Set
The document does not provide any information regarding a training set sample size. This type of device (stereotaxic instrument and navigation software) relies on geometric accuracy, image processing, and registration algorithms rather than machine learning models that typically require large training datasets with explicit ground truth labels in the same way, for example, an image classification AI would. Its functionality is based on established principles of image-guidance and tracking.
9. How Ground Truth for Training Set Was Established
As no training set is discussed or implied to be used for machine learning-based model training, there is no information on how a training set ground truth was established. The system's underlying algorithms are likely deterministic or based on classical computer vision/image processing, rather than requiring a labeled training set in the AI sense.
§ 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).