(778 days)
The Magnes II Biomagnetometer is intenced for use in diagnostic procedures that require the measurement and display of extracranial magnetic fields and information about the electrical activity of the brain as inferred from those fields.
The Magnes II Biomagnetometer system utilizes superconducting signal pickup coils and Superconducting Quantum Interference Devices (SQUIDs) to detect and amplify magnetic fields produced by electrical activity in the brain. The signals are amplified, filtered and digitized by signal processing electronics. The digitized signals are computer processed to produce displays of information about biomagnetic field strength, direction, and location.
The Magnes II Biomagnetometer system consists of: Two sensor units, one ganty mounted and one floor mounted, which house the superconducting components which are cooled to liquid helium winperature, an electronics subsystem for preliminary analog signal amplification, filtering, and analog-to-digital conversion, a computer subsystem "master analysis processor" to store, process, and display the data, a magnetically shielded room for interference reduction, a patient table for subject/patient support, and a gantry for articulation of the upper sensor.
The provided text describes a 510(k) summary for the Magnes II Biomagnetometer. However, it does not contain specific acceptance criteria, a detailed study proving the device meets those criteria, or the other specific information requested in your prompt (such as sample size, expert qualifications, adjudication methods, MRMC studies, training set details, etc.).
The document focuses on:
- Device Description: How the Magnes II works (using SQUIDs to detect brain magnetic fields).
- Intended Use: For diagnostic procedures requiring measurement and display of extracranial magnetic fields related to brain electrical activity.
- Technological Characteristics: Emphasizes the addition of a second magnetic field sensor unit compared to the original Magnes system, and the distinction from EEG in using superconducting magnetic field sensors.
- Nonclinical Tests and Results: Mentions "verification of basic physical principles" using "phantom" signal sources for localization accuracy, signal sensitivity, and background noise. It also states that tests comparing the second sensor to the original showed "no significant difference in the performance."
- Conclusions: The second sensor provides increased coverage and reduced recording time.
Therefore, I cannot populate the table or answer most of your detailed questions based on the provided text. The text does not provide the level of detail regarding device performance, study design, or ground truth establishment that you are asking for.
Here's a breakdown of what could be inferred vs. what is missing:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criterion | Reported Device Performance |
|---|---|
| Localization Accuracy | Implied criterion: Must accurately localize phantom signal sources. |
| Signal Sensitivity | Implied criterion: Must detect biomagnetic signals with sufficient sensitivity. |
| System Background Noise | Implied criterion: Background noise should be acceptable relative to biomagnetic signals. |
| Equivalence of Second Sensor | Criterion: Performance of the second sensor should be equivalent to the original sensor. |
2. Sample size used for the test set and the data provenance
- Sample Size: Not mentioned. The tests were "nonclinical" and involved "phantom" signal sources, not human data.
- Data Provenance: Not human data. "Phantom" signal sources were used.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Number of Experts: Not mentioned.
- Qualifications: Not applicable, as "phantom" signal sources were used, implying an engineered ground truth.
4. Adjudication method for the test set
- Not mentioned. Not applicable to nonclinical phantom tests.
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
- No. This is a nonclinical test of a hardware device. No mention of AI assistance or human readers.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
- The tests described are for the standalone device operating with phantom sources. There is no "algorithm only" or "human-in-the-loop" aspect to these nonclinical tests.
7. The type of ground truth used
- Engineered ground truth (from "phantom" signal sources) for characteristics like localization accuracy, signal sensitivity, and background noise.
8. The sample size for the training set
- Not applicable. This document describes tests for a medical device (hardware and associated electronics), not a machine learning model that would require a "training set."
9. How the ground truth for the training set was established
- Not applicable (no training set).
§ 882.1400 Electroencephalograph.
(a)
Identification. An electroencephalograph is a device used to measure and record the electrical activity of the patient's brain obtained by placing two or more electrodes on the head.(b)
Classification. Class II (performance standards).