(119 days)
The Intended Purpose of Leksell® Vantage™ Stereotactic System is target localization and fixation of the patient head in a coordinate system in order to perform stereotactic neurosurgical procedures, for example; deep brain stimulation, lesioning, biopsies, targeted injections, aspirations and minimal invasive tumor treatments.
The Leksell® Vantage™ Stereotactic System is a device used for minimally invasive neurosurgical procedures. It enables coordinate referencing and fixation of the patient's skull and brain during image acquisition and treatment. The coordinate referencing enables target localization and accurate stereotactic treatment of brain targets; for example for aspirations and biopsies, electrode placements, injections of cells & drugs, heamatoma evacuations as well as lesioning using a number of methodologies.
The system consists of a head frame that is fixated to the patient skull by minimally invasive disposable fixation pins and a number of accessories for frame application and imaging as well as a stereotactic arc and operating room accessories for the sterile surgical procedure.
The system is based on the established Leksell center-of-arc principle, which allows guidance of compatible interventional instruments at any trajectory angle to the brain target. Compatible interventional instruments are based on the Leksell principle of an active working length of 190 mm (as the arc radius) and use the correct mechanical interfacing of the Arc instrument stop and guide holders. Various instruments, such as biopsy needles, cannulas, and electrodes can be used with the system to perform biopsies, hematoma evacuation and injections of radioactive nuclides and cytostatic agents, puncture of cysts, positioning electrodes for stimulation/ recording or lesioning and stereotactic endoscope guidance.
The provided text describes specific acceptance criteria and the results of a study conducted to demonstrate the substantial equivalence of the Leksell® Vantage™ Stereotactic System with CT accessories to its predicate devices.
Here's a breakdown of the requested information:
1. A table of acceptance criteria and the reported device performance:
| Acceptance Criteria (Test) | Reported Device Performance and Acceptance Criteria Met |
|---|---|
| Sterilization | Test Method: Sterility validation (EtO) according to ISO 11135:2014 was performed to demonstrate that the device has a sterility assumed level (SAL) of 10-6. Tests were conducted on the predicate device (K171123). |
| Results: Results met pre-established acceptance criteria, demonstrating equivalence to the predicate device in terms of sterility. | |
| MR Testing (Safety & Compatibility) | Test Method: Device subjected to compliance testing according to ASTM F2052; ASTM F2119; ASTM F2182, ASTM F2213 and ASTM F2503, and FDA guidance regarding safety and compatibility in the MR environment. |
| Results: The device is compliant with FDA guidance and applicable consensus standards, demonstrating substantial equivalence. | |
| Accuracy | Test Method: Accuracy was tested at different levels: Total system accuracy (imaging to treatment), total mechanical accuracy, mechanical accuracy of each component, handling accuracy (e.g., repeated mounting, scale setting), and displacement from head load when fixed in the frame. |
| Results: All test cases were passed, demonstrating that the overall system accuracy of the Vantage system with CT accessories is substantially equivalent to the predicate device. The mechanical accuracy specified for both the subject and predicate devices is 0.9 mm. | |
| Design and Usability Validation | Test Method: Design and usability validation was performed by trained, competent, and professionally qualified personnel to ensure the product fulfills its intended use and user needs. The validation also aimed to ensure the effectiveness of risk control measures related to safety functions. |
| Results: No unacceptable human factor risks were identified. Residual risks were weighed against the product's benefit and deemed acceptable, demonstrating substantial equivalence to the predicate device when used with CT accessories. |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document does not explicitly state sample sizes for the test sets in the performance reports for Sterilization, MR testing, Accuracy, or Design and Usability validation. It refers to "test cases" for accuracy and "trained competent and professionally qualified personnel" for usability.
The provenance of the data (country of origin, retrospective/prospective) is not specified. However, the applicant is "Elekta Instrument AB" from Stockholm, Sweden.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
The document mentions "trained competent and professionally qualified personnel" for Design and Usability validation, but does not specify the number or specific qualifications (e.g., years of experience, specialty) of these experts. For Accuracy, Sterilization, and MR testing, it refers to testing methods and compliance with standards, implying technical personnel rather than clinical experts establishing ground truth in the traditional sense for medical imaging AI.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
The document does not describe any adjudication method (like 2+1, 3+1) for establishing ground truth, as it's not a study involving diagnostic interpretation where multiple experts would provide conflicting assessments requiring adjudication. The tests performed are engineering and usability validations against predetermined criteria and standards.
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 MRMC comparative effectiveness study was done. The device is a stereotactic system, a mechanical instrument for surgical guidance, not an AI-assisted diagnostic tool for human readers.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This refers to a hardware device without AI algorithms. Performance testing was done on the device's physical and functional properties, which could be considered standalone performance for a mechanical system. For example, "Accuracy" testing assessed the system's inherent mechanical precision.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
The "ground truth" for the various tests appears to be:
- Sterilization: The specified sterility assumed level (SAL) of 10-6 according to ISO 11135:2014.
- MR Testing: Compliance with applicable consensus safety standards (ASTM F2052, F2119, F2182, F2213, F2503) and FDA guidance.
- Accuracy: The predefined mechanical accuracy specification of 0.9 mm, determined through various measurements of the system and its components.
- Design and Usability Validation: Fulfillment of intended use and user needs, and effectiveness of risk control measures associated with safety functions, assessed by qualified personnel.
8. The sample size for the training set
This is not applicable. The device is a stereotactic system, not an AI/machine learning model that requires a training set.
9. How the ground truth for the training set was established
This is not applicable, as there is no training set for an AI model.
§ 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).