(151 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.
Here's an analysis of the provided text regarding the acceptance criteria and study for the Leksell® Vantage™ Stereotactic System:
The document (K171123) describes the Leksell® Vantage™ Stereotactic System, a device used for stereotactic neurosurgical procedures. The primary focus of the regulatory submission is to demonstrate substantial equivalence to a previously cleared predicate device (Leksell Stereotactic System, K080355). This means the study design focuses on proving the new device performs as well as the existing one, rather than establishing absolute performance thresholds.
Important Note: The provided text does not include acceptance criteria in a quantitative, pre-defined manner for all performance tests. Instead, it generally states that "Results met pre-established acceptance criteria" or "All test cases were passed." For the "Accuracy" test, it specifically mentions an equivalence to the predicate device's mechanical accuracy of 0.9 mm.
1. Table of Acceptance Criteria and Reported Device Performance
| Test | Acceptance Criteria (As Implied/Stated in Document) | Reported Device Performance |
|---|---|---|
| Biocompatibility | Pass respective biocompatibility requirements (according to ISO 10993-1, -5, -7, -10). | All tests reported to pass, judged substantially equivalent to predicate device. |
| Sterilization - devices sold as sterile | Achieve a Sterility Assurance Level (SAL) of 10⁻⁶ (according to ISO 11135:2014). | Results met pre-established acceptance criteria, demonstrating substantial equivalence. |
| Sterilization - reusable parts | Achieve a Sterility Assurance Level (SAL) of at least 10⁻⁶ when steam sterilized in 134°C-3 min or 132°C-4 min. | Results met pre-established acceptance criteria, demonstrating substantial equivalence. |
| Cleaning - reusable parts | Be clean when using methods described in IFU, with artificial blood and detection of protein residues after cleaning (according to EN ISO 15883). | All parts passed final validation and met all pre-established acceptance criteria, demonstrating substantial equivalence. |
| Shelf life and packaging/shipping testing | Maintain sterility after transport and exhibit a shelf life of three years for pre-sterilized parts (according to ASTM F1980-07, ASTM F1886-09, ASTM F1929-15, ASTM F88-15, ISO 11607-1:2006/A1:2014, ASTM D4169-14, ISO 11737-2). | All tests were passed, demonstrating sterility after transport and shelf life of three years, showing substantial equivalence. |
| MR Testing | Compliance to applicable consensus safety standards (ASTM F2052, F2119, F2182, F2213, F2503) and FDA guidance for safety and compatibility in MR environment. | The result demonstrates compliance to FDA guidance and applicable consensus standards, demonstrating substantial equivalence. |
| Accuracy | Overall system accuracy substantially equivalent to the predicate device, which has a mechanical accuracy of 0.9 mm. | All test cases were passed, demonstrating that the overall system accuracy of the Vantage system is substantially equivalent to the predicate device. Mechanical accuracy (subject device): 0.9 mm. |
2. Sample Size Used for the Test Set and Data Provenance
- The document does not explicitly state specific sample sizes for each non-clinical performance test (e.g., number of devices or components tested for biocompatibility, sterility, cleaning, or accuracy tests). The testing is described as occurring "on the subject device" or "on different levels of the subject device components."
- Data Provenance: The studies are non-clinical, performed by the manufacturer (Elekta Instrument AB). No country of origin for data is specified beyond the manufacturer's location in Stockholm, Sweden. These are prospective tests performed on the new device (Leksell® Vantage™ Stereotactic System).
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- This device is a medical instrument, not an AI or diagnostic imaging device that requires interpretation of results by human experts to establish ground truth for a test set.
- The "ground truth" for the non-clinical tests (e.g., whether a device is sterile, biocompatible, or accurate) is established by objective measurements against scientific and engineering standards, not by expert consensus or interpretation in the way it would be for an AI diagnostic tool.
- The document states that "Design and usability validation of the system has been performed by competent and professionally qualified personnel." No specific number or qualifications (e.g., "radiologist with 10 years of experience") are provided as they are not relevant for this type of device testing.
4. Adjudication Method for the Test Set
- None applicable. Adjudication methods like 2+1 or 3+1 are typically used in clinical studies or studies evaluating subjective interpretations (e.g., reading medical images) where multiple experts produce differing opinions that need to be resolved. For non-clinical, objective performance testing, results are determined by compliance to pre-defined, measurable standards.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No. An MRMC study is not mentioned because this is a physical medical device (stereotactic system), not an AI or imaging software that assists human readers in interpreting cases. The comparison is between the new device's engineering performance and validated standards/predicate device performance, not human diagnostic ability.
6. Standalone (Algorithm only without human-in-the-loop performance) Study
- N/A. This question is also not applicable. The device is a physical instrument for neurosurgery, not an algorithm. Its "standalone" performance would be its inherent mechanical accuracy and compliance with various standards, which are evaluated in the non-clinical tests described.
7. Type of Ground Truth Used
- The ground truth for the non-clinical tests is based on objective measurements against established engineering, biocompatibility, sterilization, and safety standards (e.g., ISO, ASTM, FDA guidance). For accuracy, the ground truth is a precisely measured distance (0.9 mm Mechanical Accuracy).
8. Sample Size for the Training Set
- N/A. This device does not use an "AI algorithm" that requires a training set. The term "training set" is relevant for machine learning models, not for traditional medical devices undergoing performance verification.
9. How the Ground Truth for the Training Set Was Established
- N/A. As there is no AI algorithm, there is no training set and therefore no ground truth establishment for a training set.
§ 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).