(213 days)
This device is intended for use in surgical procedures to assist in locating and mapping motor nerves through the use of mechanomyographic (MMG) signals and electrical stimulus of nerves. The device provides information directly to the surgeon to help assess a patient's neurophysiologic status by measuring and comparing MMG signals throughout a surgical procedure.
The device is intended to identify relative changes in the conduction and neural transmission ability of the nerve throughout a surgical procedure by measuring and comparing the minimum amount of electrical stimulation current (mA) required to induce a measurable MMG response (MMG nerve response threshold).
Examples of surgical applications which may require mechanomyographic (MMG) monitoring:
- Minimally invasive and open spinal surgery involving spinal fusion cages, screws, rods, plates, discs and biologics.
- Minimally invasive, open and endoscopic, direct and indirect nerve decompressions, discectomies, laminectomies, laminotomies, facetectomies, foraminotomies.
- Treatment of nerve compression, stenosis, degenerative disc disease, disc herniation, spondylolisthesis.
The Neuralytix iD3 System is a multichannel device for locating, mapping and assessing the status of motor nerves during surgical procedures. Neuralytix alerts the user of recorded mechanical activity (termed mechanomyography, or MMG) from muscles innervated by affected nerves, which may originate from operator applied electrical stimulus. The device will assist with nerve identification and assessment by alerting the surgeon when monitored nerves are activated. The device will also assist with tracking the status of monitored nerves throughout the course of surgical intervention. Neuralytix is especially useful in helping assess a patient's neurophysiologic status by measuring and identifying nerve response thresholds, or the minimum amount of electrical current (mA) necessary to elicit an MMG response. Neuralytix enables intuitive controls for measuring, recording and comparing nerve response thresholds throughout a surgical procedure to provide insights to the user as to how the conduction and neural transmission ability of a nerve may change throughout surgery.
The provided FDA 510(k) clearance letter and summary for the Neuralytix iD3 System offer details on device acceptance criteria and performance testing. However, it's important to note that the document primarily focuses on demonstrating substantial equivalence to a predicate device through engineering and performance characteristics, rather than a clinical multi-reader multi-case (MRMC) study or standalone AI performance evaluation as might be found for imaging AI devices.
Based on the provided text, the "acceptance criteria" and "study that proves the device meets the acceptance criteria" are framed within the context of demonstrating substantial equivalence to a predicate device (Sentio MMG Gen 2) and conformity to recognized consensus standards. The performance testing outlined is primarily engineering and bench-top validation rather than clinical studies with human readers or AI-only performance.
Here's a breakdown of the information as requested, with details extracted from the provided text and limitations noted where information is not present:
Acceptance Criteria and Device Performance for Neuralytix iD3 System
The acceptance criteria for the Neuralytix iD3 System are primarily defined by its ability to demonstrate substantial equivalence to its predicate device (Sentio MMG Gen 2) in terms of technological characteristics and performance, as well as adherence to relevant consensus standards for medical devices. The "study" proving acceptance is a compendium of non-clinical, bench-top performance tests, biocompatibility evaluations, and material characterizations.
The core function being tested for performance is "MMG-detection performance."
1. Table of Acceptance Criteria and Reported Device Performance
| Test / Attribute | Acceptance Criteria (Implied by "passed" as meeting standards/equivalence) | Reported Device Performance (Results/Conclusions) |
|---|---|---|
| MMG-Detection Performance (Comparative) | >99% agreement with predicate device (Sentio MMG Gen 2) when subjected to MMG-positive and MMG-negative waveforms. | All samples passed the acceptance criteria. Overall correlation was evaluated and confirmed to be >99% agreement. Substantially Equivalent. |
| Plug and Wire Disconnect Force Testing | At least 2.2N of retention force (normal to plug). | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| Hydrogel Patch Adhesion Testing | At least 4N of retention force to HDPE (skin-approximating) test surface when pulled normal from surface by Sensor Wire or Ground Wire. | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| Sterility | Sterility Assurance Level (SAL) of 10⁻⁶ (gamma irradiation per ISO 11137-1, 11137-2, 11137-3). | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| Sterile Package Integrity (Initial & Real Time Aging) | Conformity to ISO 11607-1, ISO 11607-2, ASTM F88/F88M-21 (Seal Strength), ASTM F2096-19 (Bubble-Leak). | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| Accelerated Aging (Non-Sterile Patches) | At least 4N retention force after 1 year accelerated aging per ASTM F1980-21, and PSTC 101 Type F pull testing. | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| Environmental and Transport Stability | Withstand stated transportation conditions (ASTM D4332, ASTM D4169 Cycle 13) with subsequent functional testing and package integrity checks. | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| EMC and Electrical Safety | Compliance to IEC 60601-1, IEC 60601-1-2, IEC 60601-1-6, IEC 60601-2-40, and IEC TR 60601-4-2. | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| Biocompatibility (Stim Probe) | Non-Cytotoxic, Non-sensitizer, Non-Irritant, Non-Toxic, Non-Pyrogenic, Non-Hemolytic for tissue/bone/CSF contact (ISO 10993 series). | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| Biocompatibility (Sensor/Ground Kit) | Non-Cytotoxic, Non-sensitizer, Non-Irritant for skin contact (ISO 10993 series). | All samples passed the acceptance criteria. Design inputs satisfied. Substantially Equivalent. |
| Sensor Characterization | Performance within specification with respect to low-pass filtering and % error when compared to NIST traceable reference accelerometer at multiple frequencies. | All samples passed the acceptance criteria. Design Inputs satisfied. Substantially Equivalent. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Performance Tests: The document frequently uses the phrase "All samples passed the acceptance criteria," but it does not specify numerical sample sizes for most of the individual performance (bench-top) tests. For the "Comparative Performance Evaluation" of MMG-detection, it states "a statistically significant sample" was captured, but the exact number is not provided.
- Data Provenance: The data provenance is not explicitly stated in terms of country of origin or whether a clinical dataset was retrospective or prospective. Given the nature of the tests (bench-top, signal simulation), it's not applicable in the same way as for clinical image-based AI studies. The "clinically relevant MMG signal simulation" implies simulated data rather than data from actual human patients.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- Not Applicable. The "Comparative Performance Evaluation" uses "clinically relevant MMG signal simulation" and compares the subject device's output to that of the predicate device, not to human expert interpretation of MMG signals. Therefore, there is no mention of experts establishing a ground truth for a test set in the traditional sense of clinical labeling or diagnostic interpretation.
4. Adjudication Method for the Test Set
- Not Applicable. No human adjudication method (e.g., 2+1, 3+1) is mentioned, as the primary performance evaluation is a direct comparison of the subject device's signal detection performance against a predicate device using simulated waveforms, not human interpretation.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
- No. An MRMC comparative effectiveness study was not conducted based on the provided summary. The comparison is between the subject device's MMG detection performance and the predicate device using simulated waveforms, not with human readers.
- Effect Size: Not applicable, as no MRMC study was performed.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- Yes, implicitly. The "Comparative Performance Evaluation" section describes testing the Neuralytix iD3 System's "MMG-detection performance" by subjecting it (and the predicate device) to "MMG-positive and MMG-negative waveforms." This evaluates the device's technical ability to detect MMG signals in a controlled environment, which can be considered a form of standalone technical performance (algorithm/system only). However, this is distinct from testing a standalone AI algorithm's diagnostic performance on a clinical dataset.
7. The Type of Ground Truth Used
- The ground truth for the "Comparative Performance Evaluation" was based on "clinically relevant MMG signal simulation" (i.e., known MMG-positive and MMG-negative waveforms) which were then fed into both the subject and predicate devices. This is a technical ground truth based on simulated signals, not a clinical ground truth from patient outcomes, pathology, or expert consensus on patient data.
8. The Sample Size for the Training Set
- The document does not mention a training set or any deep learning/machine learning model training process. The device's function as described (measuring mechanomyographic signals and electrical stimulation thresholds) sounds like a traditional signal processing system rather than a machine learning-based AI system that would require a distinct training set.
9. How the Ground Truth for the Training Set Was Established
- Not applicable, as no training set or machine learning model for which a ground truth would need to be established is mentioned.
Summary Limitations:
The provided FDA summary primarily addresses the substantial equivalence of the Neuralytix iD3 System to a predicate device via detailed technical and engineering comparisons and bench-top performance testing. It does not describe clinical trials, MRMC studies, or specific AI model validation processes that involve human interpretation or large, diverse clinical datasets. The "Comparative Performance Evaluation" is a technical test against simulated signals, not an evaluation of diagnostic accuracy in a clinical setting by human readers or an AI.
§ 874.1820 Surgical nerve stimulator/locator.
(a)
Identification. A surgical nerve stimulator/locator is a device that is intended to provide electrical stimulation to the body to locate and identify nerves and to test their excitability.(b)
Classification. Class II.