(337 days)
The M2 Wrist 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 Wrist MRI is a 1 Tesla high-performance solution, using NdFeB magnetic material, providing routinely 250 micron or better resolution. The system is Eddy - currents free with gradients which have high strength and a fast slew rate. The Wrist MRI is designed to ensure maximum safety of operation. Its negligible external magnetic-field eliminates the need for a specially shielded room and other limiting operational procedures. The Wrist MRI system's main components are: Magnet Sub-system, Wrist Coil, Electronics Cabinet, Aspect Imaging Proprietary Software, Computer, Isolation Transformer.
Here's a breakdown of the acceptance criteria and study information for the ASPECT IMAGING's WRIST MRI SYSTEM (K120701), based on the provided document:
Acceptance Criteria and Device Performance (Based on Non-Clinical Performance)
The document does not explicitly state quantitative "acceptance criteria" against which the device performance was measured in a table format. However, it lists several performance standards and states that the device "functioned as intended and/or met the requirements of the standard." These standards effectively serve as the acceptance criteria for the non-clinical performance.
| Acceptance Criteria (Performance Standard) | Reported Device Performance |
|---|---|
| Electrical & Mechanical Safety (IEC 60601-1) | Functioned as intended and/or met the requirements of the standard. |
| Electromagnetic Compatibility (IEC 60601-1-2) | Functioned as intended and/or met the requirements of the standard. |
| Software Validation | Functioned as intended and/or met the requirements of the standard. |
| MR Image Quality Testing | Functioned as intended and/or met the requirements of the standard. |
| NEMA MS-1-2008 Determination of Signal-to-Noise Ratio (SNR) in Diagnostic Magnetic Resonance Imaging | Functioned as intended and/or met the requirements of the standard. |
| NEMA MS 3-2008 Determination of Two-Dimensional Geometric Distortion in Diagnostic Magnetic Resonance Images (Image Uniformity Test) | Functioned as intended and/or met the requirements of the standard. |
| NEMA MS 4 (2006) Acoustic Noise Measurement Procedure for Diagnosing Magnetic Resonance Imaging Devices | Functioned as intended and/or met the requirements of the standard. |
| NEMA MS 5-2010 Determination of Slice Thickness in Diagnostic Magnetic Resonance Imaging | Functioned as intended and/or met the requirements of the standard. |
| NEMA MS 8 (2006) Characterization of the Specific Absorption Rate (SAR) for MRI Systems | Functioned as intended and/or met the requirements of the standard. |
| NEMA MS 10-2006 Determination of Local Specific Absorption Rate (SAR) in Diagnostic Magnetic Resonance Imaging | Functioned as intended and/or met the requirements of the standard. |
| NEMA MS 11-2006 Determination of Gradient-Induced Electric Fields in Diagnostic Magnetic Resonance Imaging | Functioned as intended and/or met the requirements of the standard. |
| NEMA MS 12-2006 Quantification and Mapping of Geometric Distortion for Special Applications | Functioned as intended and/or met the requirements of the standard. |
| IEC 60601-2-33 Medical electrical equipment Part 2-33: Particular requirements for the basic safety and essential performance of magnetic resonance equipment | Functioned as intended and/or met the requirements of the standard. |
| High Contrast Spatial Resolution Testing | Better than 250um area pixel resolution (stated as a technical characteristic and implies acceptance of this). |
Study Details:
Based on the provided document, the submission focuses entirely on non-clinical performance data and software validation to demonstrate substantial equivalence. No clinical study was conducted or reported.
Here's the information extracted given the lack of a clinical study:
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Sample Size Used for the Test Set and Data Provenance:
- Test Set Sample Size: Not applicable, as no clinical test set was used. Performance was assessed on the device itself against established standards.
- Data Provenance: Not applicable for clinical data. The non-clinical tests were conducted on the device components and the integrated system. The applicant is from Israel.
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Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
- Not applicable, as no clinical test set requiring expert ground truth establishment was used.
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Adjudication Method for the Test Set:
- Not applicable, as no clinical test set requiring adjudication was used.
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If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size of Human Reader Improvement:
- No, an MRMC comparative effectiveness study was not done. The submission explicitly states "Clinical Performance Data: Not Applicable."
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If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study Was Done:
- The "device" in this case is the MRI system itself, not an AI algorithm. The performance evaluation focused on the physical and software components of the MRI system as a standalone imaging device, without human interpretation for the purpose of this submission (as it was non-clinical). So, in a sense, the non-clinical tests assess the "standalone" performance of the imaging system. However, this is not an AI algorithm evaluation.
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The Type of Ground Truth Used:
- For the non-clinical performance, the "ground truth" was defined by industry performance standards (IEC, NEMA) and the device's own design specifications. The device's performance was compared against these established standards and specifications.
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Sample Size for the Training Set:
- Not applicable. This is a medical imaging device (MRI system), not an AI algorithm that requires a training set in the typical sense.
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How the Ground Truth for the Training Set Was Established:
- Not applicable, as there was no training set in the context of an AI algorithm.
In summary, this 510(k) submission successfully demonstrated substantial equivalence based on the technological characteristics and comprehensive non-clinical performance testing against recognized industry standards, and not through clinical trials or AI algorithm performance evaluation.
§ 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.