(427 days)
The NM-01/CPT neurometer is a noninvasive electrodiagnostic device intended for verifying nerve integrity in conscious adult patients, with intact skin surface.
The population of subject for whom this device may be used for diagnostic purposes would include any individual capable of communicating their perception of cutaneous sensation.
The NM-01/CPT neurometer may be conducted as a part of a routine neurological examination. The measured data can be utilized in evaluating patients suspected of having neuropathies. The measured data must be used in the context of other patient information and must be reviewed and interpreted by a physician. The device is intended for use on adults in medical clinics, healthcare practices and out-patient departments of hospitals.
The NM-01/CPT neurometer is a noninvasive device intentity in conscious adult patients, with intact skin surface. The population of subject for whom this device may be used for diagnostic purposes would include any individual capable of communicating their perception of cutaneous sensation. The NM-01/CPT neurometer may be conducted as a part of a routine neurological examination. The measured data can be utilized in evaluating patients suspected of having neuropathies. The measured data must be used in the context of other patient information and interpreted by a physician. The device is intended for use on adults in medical clinics, healthcare practices and out-patient departments of hospitals.
The NEUROMETER NM-01/CPT is a unique neurodiagnostic device that painlessly evaluates the functioning of small unmyelinated (C, small myelinated (A) and large myelinated (A) sensory nerve fibers at any cutaneous site by determining neuro selective sensory nerve conduction threshold. The electronic unit emits non-aversive transcutaneous electrical stimuli through a pair of special noninvasive electrodes in three fixed frequency ranges (thick myelincoated fiber 250Hz, thin myelin-coated fiber 2000Hz) with a manually adjustable current value. The emitted stimulus pulses canbe changed between 0.01 and 9.99 mA and their values qiven by the software are in CPT (Current Precipitation Threshold) values accepted in clinical practice (1CPT = 0.01mA). The test method is sensitive to both hyperesthetic abnormalities, and has more than 800 peer reviewed research publications documenting its diagnostic capabilities. The device can measure sensory nerve function at any cutaneous site including mucosal surfaces such as the bladder and the measures are not affected by skin temperature, edema or electromag-netic interference unlike traditional electro-diagnostic and biopsy procedures. The conducted tests are painless, noninvasive and non-aversive procedure is easy to perform and safe and harmless however it is only for profession clinical use. The evaluation of the tests result could only be approved by a medical doctor but the tests could be conducted by a trained assistant.
The provided text describes a 510(k) premarket notification for the NM-01/CPT neurometer (K240189) and its substantial equivalence to predicate devices. It includes a summary of non-clinical testing performed.
Here's an analysis of the acceptance criteria and study details based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are not explicitly stated in a numerically quantified target, but the study implies an acceptance range for the ratio of measurements between the NM-01/CPT neurometer and the predicate device (Neurometer) to be within 10%.
| Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|
| Equivalence of measured result ratios within 10% for resistance. | The ratio of the measured result equivalence was above 1 for each resistance (1, 5, 30 Kohm). The confidence intervals do not include a value of 1 in any of the cases, but in all three cases, they show a difference within 10% of the confidence intervals (90%; 11%). According to the TOST tests, the two measurements can be considered within the 10% limit. |
| Equivalence of measured result ratios within 10% for CPT values. | For CPT breakdown, the ratios are above 1 for CPT values between 10 and 250 and below 1 for CPT values above that. The confidence intervals of the ratios for values greater than 10 CPTs are (90%; 11%). The TOST tests performed indicate that the two measurements are equivalent within the 10% limit for CPT values greater than 10. |
For CPT 10, the mean of the ratio is 1.109, with a 90% confidence interval of (1.0531; 1.1648), meaning the two measurements cannot be considered equivalent within the 10% limit for CPT 10. However, the document states such values are "not expected in the population under study." |
Conclusion on Acceptance: The device generally met the implicit acceptance criteria of equivalence within a 10% limit, with a noted exception for CPT 10 values, which the submitter claims are not clinically relevant for the target population.
2. Sample Size and Data Provenance
- Test Set Sample Size: Not explicitly stated. The text mentions "Bench testing was performed on the NM-01/CPT neurometer measured values with the results of the Neurometer used in clinical practice," but it does not specify the number of resistance measurements or CPT measurements performed for this comparison.
- Data Provenance: Not explicitly stated (e.g., country of origin, retrospective/prospective). The study is described as "Bench testing," implying it was conducted in a controlled environment as opposed to a clinical trial with human subjects.
3. Number of Experts and Qualifications for Ground Truth
Not applicable. The study described is a bench test comparing the performance of the new device against a predicate device, not involving human interpretation for establishing ground truth regarding a medical condition.
4. Adjudication Method
Not applicable for a bench test comparing device measurements.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a MRMC comparative effectiveness study was not done. The study was a bench test comparing the device's measurements to a predicate device.
6. Standalone Performance Study
Yes, a standalone performance study (bench testing) was done. The NM-01/CPT neurometer's measured values were compared against the results of the legally marketed predicate device (Neurometer). This comparison assesses the algorithm/device's technical performance.
7. Type of Ground Truth Used
The "ground truth" for this bench test was the measurements obtained from the predicate device, the "Neurometer used in clinical practice." This means the new device's performance was evaluated against an established and accepted device's output.
8. Sample Size for the Training Set
Not applicable. This document describes a performance evaluation of a device, not the development of a machine learning algorithm that typically involves a training set. The device appears to be an electrodiagnostic tool that directly measures nerve conduction thresholds, rather than an AI/ML diagnostic system.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no mention of a training set or machine learning algorithm.
§ 882.1550 Nerve conduction velocity measurement device.
(a)
Identification. A nerve conduction velocity measurement device is a device which measures nerve conduction time by applying a stimulus, usually to a patient's peripheral nerve. This device includes the stimulator and the electronic processing equipment for measuring and displaying the nerve conduction time.(b)
Classification. Class II (performance standards).