(19 days)
The intended uses of the 1.5T 32-channel Head Coil and the 3T 32-channel Head Coil are, in conjunction with a Magnetic Resonance Scanner, the MR examination of the human head.
Used in the 1.5 T MAGNETOM Avanto, MAGNETOM Espree or MAGNETOM Symphony, a Tim System, the 1.5 T 32-channel Head Coil and in the 3 T MAGNETOM Trio, a Tim System, the 3T 32-channel Head Coil are indicated for uses as a diagnostic imaging device to produce transversal, sagittal, coronal and oblique images of the internal structures of the body. The images produced by the 1.5 T MAGNETOM Avanto, MAGNETOM Espree or MAGNETOM Symphony, a Tim System with the 1.5 T 32-channel Head Coil and the images produced by the 3 T MAGNETOM trio a Tim System with the 3T 32-channel Head Coil reflect the spatial distribution of protons (hydrogen nuclei) exhibiting magnetic resonance.
When interpreted by a trained physician, these images provide information that can be useful in determining a diagnosis.
The intended use of the MAGNETOM Avanto, MAGNETOM Espree or MAGNETOM Symphony a Tim System is not affected in any way by the use of the new 1.5T 32-channel Head Coil.
The intended use of the MAGNETOM Trio a Tim System is not affected in any way by the use of the new 3T 32-channel Head Coil.
The 1.5T 32-channel Head Coil and the 3T 32-channel Head Coil are receive only MR coils for imaging the human head. The coils comprises a split design for easy patient positioning. An addition mirror is provided for patient comfort. A high number of 32 receive elements has been chosen to make use of high acceleration factors in the so-called parallet imaging technique (iPAT). The inner dimensions of the coil have been chosen to be smaller than the Head Matrix Coil to optimize the signal-to-noise ratio.
The Siemens 1.5T 32-channel Head Coil and 3T 32-channel Head Coil are subject to safety and performance parameters, as outlined in the FDA Guidance document for MR Diagnostic Devices. These parameters, including Maximum Static Field, Rate of Change of Magnetic Field, RF Power Deposition, Acoustic Noise Level, Geometric Distortion, Slice Profile, Thickness and Gap, and High Contrast Spatial Resolution, were considered unaffected by the modifications described in the notification.
For the new coils, additional parameters like Biocompatibility, Signal to Noise Ratio (SNR), and Image Uniformity were also evaluated. Biocompatibility tests were not performed as no new materials were used compared to the predicate devices.
The study performed to demonstrate substantial equivalence involved laboratory testing of the new 1.5T 32-channel Head Coil and the 3T 32-channel Head Coil. The specific details of the study, such as sample sizes, data provenance, ground truth establishment methods, and expert qualifications, are not provided in the document.
The document states that Signal to Noise Ratio (SNR) and image uniformity tests according to IEC 62464-1 standard were performed. The results, as presented in the submission, demonstrated that the new coils are equivalent to the predicate devices in these performance aspects. This finding supported the claim of substantial equivalence and indicated that the technological differences did not raise new questions regarding effectiveness.
Here’s a table summarizing the available information regarding acceptance criteria and performance:
| Criterion | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Safety Parameters | ||
| Maximum Static Field | (Implicitly) Unaffected by modifications, consistent with FDA Guidance doc. for MR Diagnostic Devices. | Unaffected by the modifications described within this notification. |
| Rate of Change of Magnetic Field | (Implicitly) Unaffected by modifications, consistent with FDA Guidance doc. for MR Diagnostic Devices. | Unaffected by the modifications described within this notification. |
| RF Power Deposition | (Implicitly) Unaffected by modifications, consistent with FDA Guidance doc. for MR Diagnostic Devices. | Unaffected by the modifications described within this notification. |
| Acoustic Noise Level | (Implicitly) Unaffected by modifications, consistent with FDA Guidance doc. for MR Diagnostic Devices. | Unaffected by the modifications described within this notification. |
| Biocompatibility | New materials would require testing. | No new materials were used, therefore no new biocompatibility tests were performed. |
| Performance Parameters | ||
| Geometric Distortion | (Implicitly) Unaffected by modifications, consistent with FDA Guidance doc. for MR Diagnostic Devices. | Unaffected by the modifications described within this notification. |
| Slice Profile, Thickness and Gap | (Implicitly) Unaffected by modifications, consistent with FDA Guidance doc. for MR Diagnostic Devices. | Unaffected by the modifications described within this notification. |
| High Contrast Spatial Resolution | (Implicitly) Unaffected by modifications, consistent with FDA Guidance doc. for MR Diagnostic Devices. | Unaffected by the modifications described within this notification. |
| Signal to Noise Ratio (SNR) | Equivalence to predicate devices as per IEC 62464-1 standard. | Tests performed acc. to IEC 62464-1 standard, and results presented in the submission show they are equivalent with the predicate devices. |
| Image Uniformity | Equivalence to predicate devices as per IEC 62464-1 standard. | Tests performed acc. to IEC 62464-1 standard, and results presented in the submission show they are equivalent with the predicate devices. |
Additional Information Not Available in the Document:
- Sample size used for the test set and the data provenance: Not specified.
- Number of experts used to establish the ground truth for the test set and the qualifications of those experts: Not specified, as the performance evaluation relies on objective measurements against a standard (IEC 62464-1) rather than expert interpretation of images for ground truth.
- Adjudication method for the test set: Not applicable, as the evaluation is based on objective measurements.
- 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, as this is a device clearance for an MRI head coil, not an AI-assisted diagnostic tool.
- If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: Not applicable.
- The type of ground truth used: For SNR and Image Uniformity, the ground truth is established by the specified standards in IEC 62464-1. Other parameters are implicitly considered consistent with FDA guidance.
- The sample size for the training set: Not applicable, as this device does not involve a "training set" in the context of machine learning.
- How the ground truth for the training set was established: Not applicable.
§ 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.