(39 days)
This device is indicated for use in surgical procedures for patient-connected intraoperative nerve monitoring, i.e. assisting the surgeon in locating and mapping motor nerves through the use of electromyographic (EMG) signals and electrical stimulus of nerves.
The purpose of this 510(k) is to notify the FDA of changes that are intended to be made to the currently marketed NIM-2XL Nerve Integrity Monitor. As previously mentioned, these changes serve to improve the NIM-2XL even further: to make the device more "user friendly" and simplify its use, provide a cleaner, higher quality signal, provide additional options for documentation (printer, disk drive, and video-out) and to lower the overall cost of the system through the use of state-of-the-art componentry. Other than the changes specifically described in this notification, the device remains the same as previously provided in K934426.
Here's an analysis of the provided text regarding the NIM Monitor, focusing on acceptance criteria and study details.
Important Note: The provided document is a 510(k) summary for a premarket notification (K982595) for the NIM Monitor (Nerve Integrity Monitor). This type of document is primarily focused on demonstrating substantial equivalence to a previously cleared device, not typically on presenting full clinical study data for new acceptance criteria. Therefore, many of the requested details about specific acceptance criteria and detailed study performance will likely be absent or only broadly implied.
Acceptance Criteria and Device Performance
Based on the provided K982595 510(k) summary, the device is an updated version of a previously cleared device (NIM-2XL). The primary "acceptance criteria" here are demonstrating substantial equivalence to the predicate device and that the changes do not raise any new safety or effectiveness issues.
| Criterion Category | Specific Criterion / Performance Target | Reported Device Performance (NIM4 vs. NIM-2XL) |
|---|---|---|
| Intended Use | Same as predicate device (NIM-2XL) | "The proposed NIM4 Nerve Integrity Monitor... has the same intended use..." |
| Basic Technological Characteristics | Same as predicate device (NIM-2XL) | "...and the same basic technological characteristics as the previously cleared device..." |
| Safety | No greater risks than predicate device (NIM-2XL) | "The Hazard Analysis... confirms that the proposed modifications present no greater risks than those associated with the current system." |
| Effectiveness | No new issues of effectiveness compared to predicate device (NIM-2XL) | "...does not raise any new issues of safety or effectiveness." |
| "User-Friendly" | More user-friendly, simplified use | "serve to improve the NIM-2XL even further: to make the device more 'user friendly' and simplify its use..." |
| Signal Quality | Cleaner, higher quality signal | "...provide a cleaner, higher quality signal..." |
| Documentation Options | Additional options (printer, disk drive, video-out) | "...provide additional options for documentation (printer, disk drive, and video-out)..." |
| Cost | Lower overall system cost | "...to lower the overall cost of the system through the use of state-of-the-art componentry." |
Study Information & Ground Truth
The document does not describe a standalone clinical study with new acceptance criteria in the way one might expect for a novel device or a device with significantly altered intended use. Instead, it relies on demonstrating that the modifications made to an already cleared device do not introduce new risks or change the fundamental performance that was previously accepted.
Here's a breakdown of the requested study details:
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Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective):
- Not Applicable / Not Provided. The document does not describe a clinical "test set" in the traditional sense of evaluating new diagnostic accuracy or treatment efficacy. The evaluation performed appears to be a design verification and validation of the changes against the predicate device, including a "Hazard Analysis" and "software validation." This is an internal engineering and risk assessment process, not a clinical study with patients.
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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):
- Not Applicable / Not Provided. Ground truth for a clinical test set is not discussed because a clinical test set, as typically understood, was not used or reported here. The "ground truth" for the device's acceptable performance is implicitly the demonstrated safety and effectiveness of the predicate device, NIM-2XL.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not Applicable / Not Provided. Adjudication methods are typically for resolving discrepancies in clinical assessments, which is not relevant to the type of submission presented.
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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. This device is an intraoperative nerve monitor, not an AI-assisted diagnostic tool for human readers. An MRMC study is completely irrelevant here.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not Applicable. This is a medical device that monitors physiological signals; it inherently operates "standalone" in generating its output (EMG signals, electrical stimulation). However, its intended use is "assisting the surgeon," meaning a human (the surgeon) is always "in the loop" for decision-making based on the device's output. The concept of "standalone performance" as typically applied to an AI algorithm making a diagnosis without human input is not relevant here. The device's "performance" is its ability to accurately detect and stimulate nerves and display EMG signals.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- Implicitly, the established safety and effectiveness of the predicate device (NIM-2XL). For the changes themselves, the "ground truth" for the Hazard Analysis would be engineering standards, risk assessment methodologies, and potentially internal verification/validation testing and expert reviews (though not specified in clinical terms).
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The sample size for the training set:
- Not Applicable / Not Provided. This is not an AI/machine learning device that requires a "training set."
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How the ground truth for the training set was established:
- Not Applicable. As above, no training set is relevant for this device.
Summary of Approach in K982595:
This 510(k) submission is an example of a "special 510(k)" or "traditional 510(k) for modifications" where the focus is on demonstrating that changes to an existing cleared device do not alter its fundamental safety or effectiveness. The "study" here is primarily a design control process, including a Hazard Analysis and software validation, to confirm that the modifications maintain equivalence to the predicate device and introduce no new risks. It is not a clinical trial establishing new performance metrics.
§ 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.