(307 days)
The M2 Wrist 2 MRI System is indicated for use as a magnetic resonance imaging device for producing transverse, sagittal and coronal images of the internal structure of the wrist (in patients with an arm length > 320mm). When interpreted by a trained physician, the resultant MR images provide information that can be useful in determining a diagnosis.
The M2 Wrist 2 MRI System is a 1 Tesla, compact, high-performance solution, based on a permanent magnet. Due to its remarkable structure, the external magnetic field is very low, thus offering unique safety advantage. The system has very low Eddy currents and exhibits very low gradient-related acoustic noise. The magnet is self-shielded and thus no RF shielded room is required. The type of installation is fixed. The M2 Wrist 2 MRI System's main components are: Magnet Sub-system, Wrist Coil, Electronics Cabinet, Aspect Imaging Proprietary Software, Computer, Isolation Transformer.
Here's an analysis of the provided text regarding the acceptance criteria and study for the M2 Wrist 2 MRI System:
1. Table of Acceptance Criteria and Reported Device Performance
The provided 510(k) summary does not list specific numerical acceptance criteria with corresponding device performance metrics for diagnostic accuracy. Instead, it focuses on demonstrating that the revised device (M2 Wrist 2 MRI System) is substantially equivalent to its predicate device (M2 Wrist MRI System) and meets various safety and performance standards relevant to MRI systems.
The acceptance criteria are implicitly derived from the performance standards met, which ensure the device functions as intended and produces images of sufficient quality for diagnostic use by a trained physician. The "reported device performance" is a statement of compliance with these standards.
| Acceptance Criterion (Implicit) | Reported Device Performance |
|---|---|
| Electrical & Mechanical Safety (IEC 60601-1) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| Electromagnetic Compatibility (IEC 60601-1-2) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| Software Validation | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| MR Image Quality Testing | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| SNR (NEMA MS-1-2008) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| 2D Geometric Distortion (NEMA MS 3-2008) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| Acoustic Noise (NEMA MIS 4 (2006)) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| Slice Thickness (NEMA MS 5-2010) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| SAR (NEMA MS 8 (2006) & NEMA MS 10-2006) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| Gradient-Induced Electric Fields (NEMA MS 11 -2006) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| Geometric Distortion for Special Applications (NEMA MS 12-2006) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| Basic Safety & Essential Performance of MR (IEC 60601-2-33) | M2 Wrist 2 MRI System functioned as intended and met requirements. |
| High Contrast Spatial Resolution Testing | M2 Wrist 2 MRI System functioned as intended and met requirements. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly mention a "test set" in the context of clinical images or diagnostic performance. The performance data presented are "Non-Clinical" and consist of engineering tests and evaluations against industry standards. Therefore:
- Sample Size for Test Set: Not applicable/not explicitly stated in the context an imaging-based performance test with patient data. The tests performed are on the device itself (e.g., phantom images, electrical measurements) rather than on a dataset of patient images with ground truth.
- Data Provenance: Not applicable, as the tests are non-clinical engineering and performance evaluations.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
This information is not applicable to the non-clinical performance data presented. No "experts" were used to establish ground truth for a test set of images; rather, the device's technical specifications and image quality were assessed against predefined objective standards using test equipment.
4. Adjudication Method for the Test Set
Not applicable, as no human-read test set requiring adjudication is described.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done
No, a Multi Reader Multi Case (MRMC) comparative effectiveness study was not done. The summary explicitly states: "7. Clinical Performance Data: Not applicable". The submission focuses on non-clinical performance and substantial equivalence to a predicate device based on technical characteristics.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This device is an MRI system, not an AI algorithm. Its performance is inherent in its ability to produce diagnostic images for interpretation by a human physician, not to provide an automated diagnosis.
7. The Type of Ground Truth Used
The "ground truth" for the non-clinical tests consisted of the technical specifications and requirements defined by the various IEC and NEMA standards (e.g., specific SNR values, geometric distortion limits, acoustic noise levels). The device's performance was compared against these objective, established standards using measurement tools and phantoms.
8. The Sample Size for the Training Set
Not applicable. The M2 Wrist 2 MRI System is a medical imaging device, not an AI algorithm that requires a training set of data.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no training set for this device.
§ 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.