(104 days)
The Ziehm RFD 3D Interface is an accessory to the StealthStation™ System. It is intended to be used with the Ziehm Vision RFD 3D C-arm to automatically transfer to and register three dimensional images on the StealthStation™ System for use in imageguided spinal surgery.
The Ziehm RFD 3D Tracker works by making the Ziehm RFD 3D C-arm visible to the StealthStation™ Navigation Systems. The optical reflective markers in the tracker housings interact with the camera and software to identify the position and orientation of the C-arm detector in three-dimensional space.
When optical markers are inserted into the magnetic mounting sockets on the housing, the combination is then referred to as the tracker assembly. The optical markers interact with the camera and software to identify the position and orientation of the C-arm detector in three-dimensional space.
The integration interface (tracker and C-Arm) enables automatic transfer and registration of images received from Ziehm RFD 3D system within StealthStation system, specifically within StealthStation™ Spine software (K170011).
To enable automatic image registration, at the beginning of each scan the StealthStation™ camera captures the position of an optical tracker attached to the C-arm in relation to the patient reference frame. Upon image acquisition, the images from Ziehm RFD 3D system and associated calibration information are automatically transferred to the StealthStation™ system as a DICOM volume over an Ethernet cable. Upon completion of the DICOM volume transfer, the StealthStation™ software automatically registers the image relative to the patient reference frame.
The provided text describes the Ziehm RFD 3D Tracker, an accessory to the StealthStation System, intended for automatically transferring and registering three-dimensional images from the Ziehm Vision RFD 3D C-arm for image-guided spinal surgery.
Here's an analysis of the acceptance criteria and study data provided:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are not explicitly stated in a defined "acceptance criteria" section but can be inferred from the "Accuracy testing values" for the device. The "reported device performance" is the measured accuracy.
| Metric (Inferred Acceptance Criterion) | Reported Device Performance (Ziehm RFD 3D Tracker) | Predicate Device Performance (K022414) |
|---|---|---|
| Mean Accuracy | 0.79 mm | 1.3 mm |
| Upper Reliability (95% confidence) | 1.73 mm | 2.30 mm |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the sample size for the test set. It mentions "Testing conducted to demonstrate the performance," but details regarding the number of cases or scans are absent.
The data provenance (country of origin, retrospective/prospective) is not specified.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not provided. The document does not describe how ground truth was established for the accuracy testing.
4. Adjudication Method for the Test Set
The document does not describe any adjudication method used for the test set.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No MRMC comparative effectiveness study is mentioned. The study focuses on the device's accuracy rather than human reader improvement with or without AI assistance.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
This is a standalone performance test. The "Ziehm RFD 3D C-arm Accuracy for StealthStation™ S8" test directly measures the accuracy of the device's integration and image registration, implying an assessment of the algorithm's performance without direct human intervention in the measurement process itself. The "human-in-the-loop" aspect during surgical use would be for navigation after image registration, not for the accuracy measurement of the registration step itself.
7. The Type of Ground Truth Used
The document does not explicitly state the type of "ground truth" used for accuracy testing. Given the nature of a stereotaxic instrument and accuracy testing in this context, it is highly likely that a precisely measured physical phantom or reference markers with known spatial relationships would be used as the ground truth. This would fall under a form of physical measurement/phantom-based ground truth, not expert consensus, pathology, or outcomes data.
8. The Sample Size for the Training Set
The document does not mention any training set or machine learning models. The device functionality described is related to image transfer and registration based on optical tracking and calibration, not a learned algorithm that requires a separate training set.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as no training set is mentioned or implied.
§ 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).