(118 days)
The Optima™ MR450w is a whole body magnetic resonance scanner designed to support high resolution, high signal-to-noise ratio, and short scan times. It is indicated for use as a diagnostic imaging device to produce axial, sagittal, coronal, and oblique images, spectroscopic images, parametric maps, and/or spectra, dynamic images of the structures and/or functions of the entire body, including, but not limited to, head, neck, TMJ, spine, breast, heart, abdomen, pelvis, joints, prostate, blood vessels, and musculoskeletal regions of the body. Depending on the region of interest being imaged, contrast agents may be used.
The images produced by the Optima™ MR450w reflect the spatial distribution or molecular environment of nuclei exhibiting magnetic resonance. These images and/or spectra when interpreted by a trained physician yield information that may assist in diagnosis.
The 1.5 GE Optima MR450w features a superconducting magnet operating at 1.5 Tesla. The data acquisition system accommodates up to 32 independent receive channels in various increments, and multiple independent coil elements per channel during a single acquisition series. The system uses a combination of time-varying magnetic fields (gradients) and RF transmissions to obtain information regarding the density and position of elements exhibiting magnetic resonance. The system can image in the sagittal, coronal, axial, oblique and double oblique planes, using various pulse sequences and reconstruction algorithms. The Silenz Imaging Application using the 3D Radial Pulse sequence reduces the acoustic noise that is generated during an MR examination. This application is compatible on the Optima MR450w system with GEM configuration. The 1.5T GE Optima MR450w is designed to conform to NEMA DICOM standards (Digital Imaging and Communications in Medicine).
Here's an analysis of the provided text regarding the Optima MR450w, focusing on acceptance criteria and supporting studies:
It is important to note that the provided text is a 510(k) Summary for a modification to an existing MRI device (addition of the Silenz Imaging Application to the Optima MR450w). As such, it primarily focuses on demonstrating substantial equivalence to the predicate device, rather than proving novel clinical efficacy or establishing new clinical performance targets as would be the case for an entirely new device.
Acceptance Criteria and Reported Device Performance
The document does not explicitly state specific quantitative acceptance criteria or a table of performance metrics for the Optima MR450w with the Silenz application in the traditional sense of a clinical performance study (e.g., sensitivity, specificity, accuracy against a gold standard).
Instead, the acceptance criteria are implicitly met by demonstrating compliance with recognized standards and by verification and validation activities ensuring the device performs as intended and is equivalent to the predicate.
The reported device performance is qualitative, focused on maintaining existing standards and functionality:
| Acceptance Criterion (Implicit) | Reported Device Performance |
|---|---|
| Compliance with IEC 60601-1 Series (Medical Electrical Equipment) | Device is in compliance. |
| Compliance with IEC 62304 (Medical Device Software) | Device is in compliance. |
| Compliance with ISO 14971 (Risk Management) | Device is in compliance. |
| Compliance with NEMA DICOM Standards | Device is in compliance (PS3.1-3.18). |
| Maintenance of high resolution | The device is still "designed to support high resolution." |
| Maintenance of high signal-to-noise ratio | The device is still "designed to support high signal-to-noise ratio." |
| Maintenance of short scan times | The device is still "designed to support... short scan times." |
| Silenz Imaging Application functions as intended (reduces acoustic noise) | "The Silenz Imaging Application using the 3D Radial Pulse sequence reduces the acoustic noise that is generated during an MR examination." |
| No alteration of overall technology of the Optima MR450w System | "The addition of the Silenz feature does not alter the overall technology of the Optima MR450w System." |
| Safety and Effectiveness substantially equivalent to predicate | "GE Healthcare considers the Optima MR450w to be as safe, as effective, and performance is substantially equivalent to the predicate device." |
Study Details
The document explicitly states that no external clinical studies were required to support substantial equivalence. The "studies" mentioned are internal verification and validation activities.
1. Sample size used for the test set and the data provenance:
* Test Set Sample Size: Not specified. The document mentions "Internal scans were conducted as part of validation for workflow and image quality." It does not provide a number of scans or distinct subjects/patients used for these internal tests.
* Data Provenance: "Internal scans" implies the data was generated within GE Healthcare, likely on their own systems for testing purposes. The country of origin and whether it was retrospective or prospective is not specified, but typically, internal validation scans are prospective as they are specifically generated for testing.
2. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
* Not specified. The document highlights "Testing on unit level," "Integration testing," and "Performance testing" with "passing results per the pass/fail criteria defined in the test cases." It also mentions "Simulated use testing."
* The interpretation of images is for "a trained physician" to yield information for diagnosis, but this refers to the intended use of the device, not the ground truth establishment for the internal validation studies.
3. Adjudication method for the test set:
* Not applicable/Not specified. The internal validation focused on technical performance rather than clinical diagnostic accuracy requiring adjudicated ground truth for a test set. The validation used "pass/fail criteria defined in the test cases."
4. 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 MRMC comparative effectiveness study was done.
* This device is an MRI scanner, and the "Silenz Imaging Application" is a feature to reduce acoustic noise, not an AI or CAD system intended to assist human readers in diagnosis. Therefore, the concept of improving human readers with AI assistance does not apply here.
5. If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
* Not applicable in the context of an "algorithm only" performance study for diagnostic AI. The device is a whole-body MRI scanner. Its performance is inherent in the image acquisition and reconstruction, not a standalone diagnostic algorithm.
6. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
* For the internal validation "workflow and image quality" scans, the ground truth would likely be based on technical specifications, industry standards for image quality, and expert review (though not explicitly detailed) of the acquired images to confirm they met predefined quality metrics (e.g., signal-to-noise ratio, spatial resolution, artifact levels, and successful noise reduction). It would not be clinical ground truth like pathology or outcomes data.
7. The sample size for the training set:
* Not applicable. This device is an MRI scanner, not a machine learning algorithm that requires a "training set" in the typical sense for diagnostic AI. While the internal development of the Silenz application (which likely involves signal processing and perhaps some optimization algorithms) would have utilized data, it's not described as a "training set" for a diagnostic AI.
8. How the ground truth for the training set was established:
* Not applicable, as there is no "training set" for a diagnostic AI algorithm in this context.
§ 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.