(70 days)
The Medrad Phased Array 1.5T Shoulder Imaging Surface Coil is for use only with the GEMS family of Super Conductor MR Systems. An anterior loop pair is combined with a posterior loop. The coil is designed to receive RF excitation from the protons of the hydrogen nuclei as a result of the scanner exciting these protons. The coil is designed for anatomical imaging of shoulder region and the upper and lower extremeties with a specific size and shape to facilitate placement on the anatomy area of interest. This placement results in a higher Signal To Noise Ratio(SNR) in the region near the surface coil. The greater SNR permits more effective imaging through the use of a smaller FOV and thinner slices.
The intended ROI for imaging includes the anterior and posterior musculoskeletal area of the shoulder and the upper and lower extremeties.
The Medrad Phased Array 1.5T Shoulder Imaging Surface Coil is intended to aid physician diagnosis in the shoulder, upper, and lower extremety regions.
Patient fitness and suitability for MRI must be determined by the individual physician trained in the field of Diagnostic Resonance Imaging.
The Medrad Phased Array 1.5T Shoulder Imaging Surface Coil is a rigid RF receive only magnetic field pickup coil that is designed to enhance imaging of the human shoulder and the upper and lower extremeties. It consist of an anterior and posterior coils which interfaces with the multi-coil port on the GEMS Signa System. The coil is intended for use in all imaging planes, with a field of view(FOV) of at least 12 centimeters and less than 25 centimeters.
The Medrad Phased Array 1.5T Shoulder Imaging Surface Coil is designed to provide high resolution diagnostic images under the supervision of a physician who is trained in the field of Diagnostic Resonance Imaging.
The ABS outer housing of the coil has been designed to provide an enduring enclosure for the coil electrical components. Durability tests are conducted to verify the integrity of the coil structure. Additionally, the coil will not contain any ferrous nickel, ferrite or other magnetic materials which would negatively impact coil performance. The coil is also designed to assure that the components of the coil that come into contact with the patient will not have surface temperatures exceeding 41 degrees Celsius as a result of heating due to dielectric losses.
Medrad, Inc. believes the Medrad Phased Array 1.5T Shoulder Imaging Surface Coil is substantially equivalent to the Medrad Phased Array 1.5T Shoulder Imaging Surface Coil identified in 510(k) - K960901. The proposed Phased Array 1.5T Shoulder Imaging Surface Coil is the same coil that was determined Substantially Equivalent in 510(k) - K96090. This 510(k) is being submitted for addition of upper and lower extremities imaging to the Intended Use of the device and for the addition of an optional third coil(posterior paddle) to the device.
This device is a medical accessory, specifically an MRI surface coil, not a software algorithm. Therefore, many of the requested categories for AI/software-based devices (like sample sizes for test and training sets, number and qualifications of experts, adjudication methods, MRMC studies, and ground truth types) are not applicable.
However, I can extract the acceptance criteria and the studies performed to meet them for this MRI surface coil based on the provided document.
Acceptance Criteria and Device Performance for Medrad Phased Array 1.5T Shoulder Imaging Surface Coil
| Acceptance Criteria Category | Specific Criteria/Test | Reported Device Performance/Study Outcome |
|---|---|---|
| Performance - Image Quality | Signal-to-Noise Ratio (SNR) | Evaluated using NEMA Standard No. 6. Clinical testing substantiated equivalent SNR with the predicate coil. Increased SNR demonstrated. |
| Performance - Image Uniformity | Image Non-Uniformity | Evaluated using NEMA Standards. Contours of axial, sagittal, and coronal images were constructed. |
| Safety - Temperature Rise | Maximum Surface Temperature (patient contact) | Designed to assure patient-contacting components do not exceed 41 degrees Celsius due to dielectric losses. Safety tests conducted to present temperature rise test results under moderate duty cycle scan conditions. |
| Safety - Electrical | Dielectric Strength | IEC 601-1 dielectric strength test results produced. |
| Durability/Integrity | Coil Structure Durability | ABS outer housing designed for enduring enclosure. Durability tests conducted to verify integrity. |
| Material Compatibility | Absence of Ferrous Materials | Designed to not contain ferrous nickel, ferrite, or other magnetic materials that would negatively impact coil performance. |
| Clinical Equivalence | Equivalent Morphological Detail | Clinical testing with images obtained substantiated equivalent morphological detail with the predicate coil. Image clarity and morphological detail demonstrated. |
Studies Conducted (as applicable for a medical device accessory):
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Sample size for the test set and data provenance:
- Not applicable as this is a hardware device (MRI coil) undergoing engineering and performance verification, not a diagnostic algorithm. The "clinical testing" mentioned involved obtaining images, likely from a small number of volunteers or phantoms, rather than a large patient cohort for diagnostic algorithm validation. The document does not specify a numerical sample size for "test set" in an algorithmic sense.
- Data provenance: Implied to be internal testing at Medrad, Inc. No country of origin for patient data (as it's not patient data in the sense of an algorithm test set) or retrospective/prospective status is relevant.
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Number of experts used to establish the ground truth for the test set and qualifications of those experts:
- Not applicable. Ground truth, in the context of an MRI coil, relates to its physical and electrical properties, and its ability to produce good quality images (measured by metrics like SNR and uniformity) and be clinically useful (demonstrated by "morphological detail"). These are assessed by engineers and imaging specialists, not clinical experts establishing diagnostic "ground truth" for disease states. The document states the coil is "intended to aid physician diagnosis" and used "under the supervision of a physician who is trained in the field of Diagnostic Resonance Imaging."
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Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Not applicable for this type of device and study. Adjudication methods are typically for resolving discrepancies in expert interpretations of images for diagnostic algorithm validation.
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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 not an AI-enabled device.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Not applicable. This is a hardware component. Its "standalone" performance refers to its physical and electrical characteristics and the image quality it can generate, as measured by NEMA standards and clinical image acquisition.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- For physical and electrical performance (SNR, non-uniformity, temperature, dielectric strength): Engineering specifications and standardized test protocols (NEMA Standards No. 6, IEC 601-1).
- For clinical image quality ("morphological detail"): Comparison against images obtained with a predicate device. This is a qualitative assessment by imaging specialists or physicians, aimed at demonstrating equivalence, not establishing a "ground truth" for a diagnosis.
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The sample size for the training set:
- Not applicable. This is a hardware device, not an algorithm. There is no concept of a "training set" in this context.
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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.