(28 days)
The Mag Vita TMS Therapy System is indicated for the treatment of Major Depressive Disorder in adult patients who have failed to recieve satisfactory improvement from prior antidepressant medication in the current episode
The MagVita TMS Therapy System is a computerized, electromechanical medical device that produces and delivers non-invasive, magnetic fields to induce electrical currents directed at regions of the cerebral cortex. The Mag Vita TMS Therapy System is indicated for Treatment of Major Depressive Disorder in adult patients who have failed to receive satisfactory improvement from prior antidepressant medication in the current episode. Transcranial magnetic stimulation (TMS) is a non-invasive technique for stimulating brain and neural tissue. The principle of magnetic stimulation is implicit in Faraday's law. The pulses of current are generated with a circuit containing a capacitor connected to the stimulating coil. With the capacitor charged to a certain level, the conducting state will cause the discharging of the capacitor through the coil. A magnetic field is generated proportional to this current. The rapid change in the magnetic field induces a current in conducting materials e.g. the body tissue. If the current induced in the human body is of sufficient amplitude and duration, it will excite neurons. In the MagVita TMS therapy system TMS pulses are applied repetitively at a frequency of 10Hz. Such stimulation has been shown to be effective in modulating cortical excitability. The observed and documented increase in cortical excitability after high frequency (10Hz) repetitive transcranial magnetic stimulation has been shown to persist beyond the duration of the train of stimulation. Repetitive Magnetic stimulation with the MagVita TMS therapy system is applied to the human brain on the left dorsolateral prefrontal cortex (DLPFC).
The provided document is a 510(k) summary for the MagVita TMS Therapy System (K171481). This document asserts substantial equivalence to predicate devices rather than proving performance against specific acceptance criteria through a clinical study designed for that purpose. Therefore, much of the requested information regarding acceptance criteria and a study proving the device meets them, particularly in terms of clinical efficacy against numerical thresholds, is not present in this document.
The document focuses on demonstrating that the modified MagVita TMS Therapy System (K171481) is as safe and effective as previously cleared predicate devices (MagVita TMS Therapy System, K150641, and Neurostar TMS Therapy System, K160703). The primary modification is a reduction in inter-train interval, leading to shorter treatment times.
Here's a breakdown of the information that can be extracted or inferred based on the provided text, and what is missing:
1. A table of acceptance criteria and the reported device performance
The document does not provide a formal table of explicit acceptance criteria with numerical thresholds for clinical performance (e.g., specific rates of symptom reduction or remission). Instead, it states that the device is "safe and effective," and that "all other identified differences between the three systems are minor and without impact on safety or efficacy."
The table provided in the document compares various technical specifications and operational parameters of the subject device to its predicates. These comparisons serve as the "performance" data to argue for substantial equivalence, rather than direct measurements against pre-defined clinical acceptance criteria.
| Criteria | MagVita TMS Therapy System (K171481) | Predicate: MagVita TMS Therapy System (K150641) | Predicate: NeuroStar TMS Therapy System (K160703) |
|---|---|---|---|
| Performance (Treatment Parameters) | |||
| Waveforms | Biphasic | Biphasic | Biphasic |
| Frequency | 0.1 - 30 pulses/second or 0.1 - 100 pulses/second (depending on model) | 0.1 - 30 pulses/second or 0.1 - 100 pulses/second (depending on model) | 0.1 - 30 pulses/second |
| Stimulation Intensity (Recommended Standard) | 120% MT | 120% MT | 120% MT |
| Repetition Rate (Recommended Standard) | 10 Hz | 10 Hz | 10 Hz |
| Train Duration (Recommended Standard) | 4 sec | 4 sec | 4 sec |
| Inter-train Interval (Recommended Standard) | 11-26 sec | 26 sec | 11-26 sec |
| Pulses/Session (Recommended Standard) | 3000 | 3000 | 3000 |
| Treatment Duration (Recommended Standard) | 18.8 min | 37 min | 18.8 min |
| Amplitude in SMT units | 0 - 1.7 | 0 - 1.7 | 0.22 - 1.6 |
| Pulse width | 290 μs, Biphasic sinusoid waveform | 290 μs, Biphasic sinusoid waveform | 185 μs (±10%), Biphasic sinusoid waveform |
| Frequency Range (Coil specific?) | 0.1-30 pps or 0.1-100 pps (depending on model) | 0.1-30 pps or 0.1-100 pps (depending on model) | 0.1-30 pps |
| Technical Characteristics | |||
| Coil Configuration | Figure-of-eight coil, Air core | Figure-of-eight coil, Air core | Figure-of-eight coil, Ferromagnetic core |
| Cooling | Liquid cooling | Liquid cooling | Ferrofluidic cooling |
| Standards met | ISO 13485:2012, IEC60601-1 3rd edition, IEC60601-1-1, IEC60601-1-2 | ISO 13485:2012, IEC60601-1 3rd edition, IEC60601-1-1, IEC60601-1-2 | ISO 13485:2003, IEC60601-1, IEC60601-1-2 |
| Electrical safety | Complies with IEC60601-1 3rd edition, and IEC60601-1-2 | Complies with IEC60601-1 3rd edition, and IEC60601-1-2 | Complies with IEC60601-1 and IEC60601-1-2 |
2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective)
This information is not provided as the submission is a 510(k) for substantial equivalence, not a clinical trial report with a test set of patient data for efficacy evaluation. The "test set" in this context refers to the device's adherence to the technical specifications of its predicates. Non-clinical performance data for components was "tested as required" and cleared in previous 510(k) submissions (K091940 and K150641), but no details on sample sizes or data provenance are given for these tests.
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)
This information is not applicable/not provided. The "ground truth" in this submission relates to the technical specifications and operational parameters, which are established through engineering design, testing, and regulatory standards, not expert clinical consensus on patient data.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set
This information is not applicable/not provided. Adjudication methods are typically used in clinical studies when establishing ground truth from multiple expert interpretations of medical data. This document focuses on technical equivalence.
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
This information is not applicable/not provided. An MRMC study is relevant for diagnostic devices often involving human interpretation of images or other data with and without AI assistance. This device is a therapeutic system (rTMS) for Major Depressive Disorder, not a diagnostic imaging device. It does not involve "human readers" in the sense of interpreting outputs that an AI could also interpret.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done
This information is not applicable/not provided. This device is a physical therapeutic system and does not function as an "algorithm only" device without human involvement. It requires a trained clinician for setup, motor threshold determination, coil positioning, and ongoing patient monitoring.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The "ground truth" in this context is based on:
- Compliance with established medical device standards (e.g., ISO 13485:2012, IEC60601-1, IEC60601-1-1, IEC60601-1-2).
- Demonstration of technical and operational equivalence to predicate devices cleared by the FDA, which were previously determined to be safe and effective based on their own clinical evidence (or substantial equivalence to even earlier devices).
- The premise that minor modifications (like adjusted inter-train interval for shorter treatment time) do not introduce new safety concerns or alter efficacy, meaning the "ground truth" of safety and efficacy established for the predicates applies.
8. The sample size for the training set
This information is not applicable/not provided. No "training set" of patient data is mentioned or implied, as this is a traditional medical device submission for a physical therapy system, not an AI/machine learning algorithm that requires a training set.
9. How the ground truth for the training set was established
This information is not applicable/not provided for the same reasons as point 8.
§ 882.5805 Repetitive transcranial magnetic stimulation system.
(a)
Identification. A repetitive transcranial magnetic stimulation system is an external device that delivers transcranial repetitive pulsed magnetic fields of sufficient magnitude to induce neural action potentials in the prefrontal cortex to treat the symptoms of major depressive disorder without inducing seizure in patients who have failed at least one antidepressant medication and are currently not on any antidepressant therapy.(b)
Classification. Class II (special controls). The special control is FDA's “Class II Special Controls Guidance Document: Repetitive Transcranial Magnetic Stimulation System.” See § 882.1(e) for the availability of this guidance document.