(232 days)
The Dual Tuned Head Coils 3T are indicated for use as a diagnostic imaging device accessory to produce transverse, sagittal, coronal and oblique images, spectroscopic images and/or spectra, and that displays the internal structure and/or function of the head. These images and/or spectra when interpreted by a trained physician yield information that may assist in diagnosis.
The Dual Tuned Head Coils 3T are transmit/receive volume coils to detect radiofrequency (RF) signals of hydrogen (1H) nuclei in combination with either phosphorus (31P), carbon (13C) or sodium (23Na) nuclei. Each coil consists of two single quadrature resonators, one of which is always tuned to the proton frequency, the other being tuned to either phosphorus, carbon or sodium frequency.
The device in question is a component of an MRI system (Dual Tuned Head Coils 3T) and as such, its acceptance criteria and performance are focused on its technical contribution to image quality and safety, rather than diagnostic accuracy like an AI algorithm. Therefore, many of the requested points regarding diagnostic performance, ground truth, experts, and human-in-the-loop studies are not applicable.
Here's an analysis based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Parameter | Acceptance Criterion (implicitly met by equivalence)* | Reported Device Performance |
|---|---|---|---|
| Safety | Biocompatibility | No new materials in contact with patient. | Met (No new materials, no biocompatibility tests needed). |
| RF Power Deposition (SAR) | Compliance with NEMA MS 8-2008 | Performed according to NEMA MS 8-2008. | |
| Maximum Static Field | Unaffected by modifications | Unaffected. | |
| Rate of Change of Magnetic Field | Unaffected by modifications | Unaffected. | |
| Acoustic Noise Level | Unaffected by modifications | Unaffected. | |
| Performance - Imaging | Signal to Noise Ratio (SNR) | Equivalent to predicate devices (NEMA MS 1-2008) | Showed equivalence with predicate devices. |
| Image Uniformity | Equivalent to predicate devices (NEMA MS 1-2008) | Showed equivalence with predicate devices. | |
| Slice Profile, Thickness and Gap | Equivalent to predicate devices (NEMA MS 5-2003) | Showed equivalence with predicate devices. | |
| Geometric Distortion | Unaffected by modifications | Unaffected. | |
| High Contrast Spatial Resolution | Unaffected by modifications | Unaffected. | |
| Performance - Spectroscopy | Spectral Resolution | Performed and results presented to demonstrate equivalence. | Carried out. |
| Signal to Noise Ratio | Performed and results presented to demonstrate equivalence. | Carried out. | |
| Decoupling | Performed and results presented to demonstrate equivalence. | Carried out. | |
| Spatial Localization Accuracy | Unaffected by modifications | Unaffected. | |
| Peak Assignment Accuracy | Unaffected by modifications | Unaffected. | |
| Solvent Suppression | Unaffected by modifications | Unaffected. |
Note: The document states that "the results presented in this submission show that they are equivalent with the predicate devices" for several performance parameters. This implies the acceptance criterion was to demonstrate equivalence to the predicate devices based on established NEMA standards or other tests.
2. Sample Size Used for the Test Set and the Data Provenance
- Sample Size: Not explicitly stated. The tests conducted were laboratory-based performance tests on the device itself, rather than clinical studies involving human patients or a specific "test set" of images/data in the typical sense of an AI study.
- Data Provenance: The tests were conducted in a laboratory setting by the manufacturer, Rapid Biomedical GmbH, in Germany. The data is thus internal to the manufacturer, from device testing.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
- Not Applicable. This device is a hardware component (MRI coil). The "ground truth" here is the physical performance and safety metrics of the coil itself, measured through standardized tests (e.g., NEMA standards) on a phantom or test object, not clinical interpretations by human experts.
4. Adjudication Method for the Test Set
- Not Applicable. As per point 3, there was no "test set" requiring adjudication by human experts for diagnostic accuracy. The assessment was based on objective, quantifiable engineering and physics measurements.
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
- Not Applicable. This is a hardware device (MRI coil), not an AI algorithm. No MRMC study was performed as it's not relevant to demonstrating the safety and effectiveness of an MRI coil.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was Done
- Not Applicable. This is a hardware device (MRI coil), not an algorithm. Performance tests were done on the standalone device.
7. The Type of Ground Truth Used
- The "ground truth" for this device's performance relies on objective physical measurements against established standards (e.g., NEMA MS 1-2008, NEMA MS 3-2008, NEMA MS 5-2003, NEMA MS 8-2008) and comparison to the performance of predicate devices. For safety parameters (like static field, acoustic noise), the ground truth is adherence to general safety guidelines or the fact that modifications did not affect these parameters.
8. The Sample Size for the Training Set
- Not Applicable. This is a hardware device, not a machine learning model. There is no concept of a "training set" in this context.
9. How the Ground Truth for the Training Set Was Established
- Not Applicable. As per point 8, there is no training set for this hardware device.
Summary of the Study that Proves the Device Meets Acceptance Criteria:
The study involved a series of laboratory tests designed to evaluate the safety and performance of the Dual Tuned Head Coils 3T. These tests included:
- RF Power Deposition (SAR) determination: Performed according to NEMA MS 8-2008.
- Imaging Performance:
- Signal to Noise Ratio (SNR) tests according to NEMA MS 1-2008.
- Image Uniformity tests according to NEMA MS 3-2008.
- Slice Profile tests according to NEMA MS 5-2003.
- Spectroscopy Performance:
- SNR tests.
- Spectral Resolution tests.
- Decoupling tests.
Additionally, biocompatibility was addressed by confirming that no new patient-contacting materials were used, thus precluding the need for new biocompatibility tests. Other general safety and performance parameters (Maximum Static Field, Rate of Change of Magnetic Field, Acoustic Noise Level, Geometric Distortion, High Contrast Spatial Resolution, Spatial Localization Accuracy, Peak Assignment Accuracy, Solvent Suppression) were deemed "unaffected by the modifications."
The results of these laboratory tests demonstrated "equivalence with the predicate devices," thereby supporting the manufacturer's claim of substantial equivalence and showing that the technological differences did not raise new questions pertaining to safety and effectiveness, as required for 510(k) clearance.
§ 892.1000 Magnetic resonance diagnostic device.
(a)
Identification. A magnetic resonance diagnostic device is intended for general diagnostic use to present images which reflect the spatial distribution and/or magnetic resonance spectra which reflect frequency and distribution of nuclei exhibiting nuclear magnetic resonance. Other physical parameters derived from the images and/or spectra may also be produced. The device includes hydrogen-1 (proton) imaging, sodium-23 imaging, hydrogen-1 spectroscopy, phosphorus-31 spectroscopy, and chemical shift imaging (preserving simultaneous frequency and spatial information).(b)
Classification. Class II (special controls). A magnetic resonance imaging disposable kit intended for use with a magnetic resonance diagnostic device only is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.