(36 days)
The 16ch Tx/Rx Knee SPEEDER is intended for use with Toshiba 1.5T MR systems to produce diagnostic images of the knee, wrist, hand, and forefoot that can be interpreted by a trained physician.
The 16ch Tx/Rx Knee SPEEDER is a transmit/receive, 16-channel receive coil, switchable between 15-channel receive array and 1-channel birdcage receive, and designed for magnetic resonance imaging (MRI) using Toshiba 1.5T MRI systems. The 16ch Tx/Rx Knee SPEEDER is intended to be used for imaging the knee, wrist, hand and forefoot.
The 16ch Tx/Rx Knee SPEEDER is a reusable, non-invasive device with limited exposure with regard to duration of contact with the body. All coil elements are enclosed in a rigid plastic housing which is fire-rated, has impact and tensile strength, and has been tested for biocompatibility.
The 16ch Tx/Rx Knee SPEEDER also includes the comfort pads listed in Table 1. The coil is provided with comfort pads.
The provided document describes the 16ch Tx/Rx Knee SPEEDER, a magnetic resonance diagnostic device, and its performance evaluation for FDA 510(k) clearance.
Here's an analysis of the acceptance criteria and the study proving the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Criteria | Reported Device Performance |
|---|---|---|
| Biocompatibility | Materials in direct/indirect contact with patient biological tissues/cells/fluids should have a history of safe use or be assessed per ISO 10993-1. For surface-contacting, limited exposure devices, testing for cytotoxicity (ISO 10993-5) and irritation/sensitization (ISO 10993-10) is required. | All patient-contacting materials either have a history of safe use or were assessed according to ISO 10993-1. Where testing was performed, materials were tested for cytotoxicity per ISO 10993-5 and for irritation/sensitization per ISO 10993-10. |
| Electrical Safety | Verification in accordance with AAMI/ANSI ES60601-1. | Verified in accordance with AAMI/ANSI ES60601-1. |
| Electromagnetic Compatibility (EMC) | Verification in accordance with IEC 60601-2-33. | Verified in accordance with IEC 60601-2-33. |
| Surface Heating | Measured temperature of the coil surface should not exceed 41°C, tested per AAMI/ANSI ES60601-1. | The measured temperature of the coil surface never exceeded the maximum limit of 41°C. |
| Specific Absorption Rate (SAR) | SAR should be controlled by the MR system within IEC60601-2-33 limits. Measured SAR from the local transmitter coil should be below the SAR displayed from the system, tested per NEMA MS-8. | SAR was tested per NEMA MS-8. Results showed that the measured SAR from the 16ch Tx/Rx Knee SPEEDER local transmitter was below the SAR displayed from the system. The Titan System SAR Management system effectively limits local SAR. |
| Image Performance (Bench) - SNR & Uniformity | Conform to predetermined acceptance criteria as analyzed per NEMA MS-1, MS-6, and MS-9. | SNR and uniformity were analyzed per NEMA MS-1, MS-6, and MS-9 and were found to conform to predetermined acceptance criteria. |
| Image Performance (Clinical) - Diagnostic Quality | Produce diagnostic quality images of the intended anatomies (knee, hand, wrist, forefoot), as demonstrated by clinical images from volunteer scanning. | Clinical images from volunteer scanning of the knee, hand, wrist, and forefoot were obtained and used to demonstrate that the device produces diagnostic quality images of the intended anatomies. |
2. Sample Size Used for the Test Set and Data Provenance
- Biocompatibility: Not explicitly stated how many material samples were tested, but the testing was done per ISO standards. Data provenance is not specified (e.g., country of origin, retrospective/prospective).
- Electrical Safety & EMC: No specific sample size for device testing, typically this involves testing one or a few representative units. Data provenance is not specified.
- Surface Heating & SAR: No specific sample size beyond "the coil" (implying at least one unit) being tested. Data provenance is not specified.
- Image Performance (Bench): No specific sample size beyond "the 16ch Tx/Rx Knee SPEEDER" (implying at least one unit) being tested. Data provenance is not specified.
- Image Performance (Clinical): "Clinical images from volunteer scanning" were obtained. The number of volunteers or scans is not specified. The data provenance is generally considered prospective, as it involves newly acquired data for the purpose of the study. The country of origin is not specified.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- For the clinical image performance, the document states that images "can be interpreted by a trained physician." However, it does not specify the number of experts used to establish ground truth from these clinical images, nor their specific qualifications (e.g., "radiologist with 10 years of experience"). It only states the images demonstrated "diagnostic quality."
4. Adjudication Method for the Test Set
- The document does not describe any formal adjudication method (e.g., 2+1, 3+1, none) used for the clinical images. It only mentions that the images "can be interpreted by a trained physician," implying the assessment of "diagnostic quality" may have been a general consensus or review, but no structured adjudication process is detailed.
5. 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, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This device is an MRI coil, not an AI-powered diagnostic algorithm. Therefore, the concept of human readers improving with or without AI assistance does not apply to this submission.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- No, a standalone algorithm performance study was not relevant or performed. This device is a hardware component (an MRI coil) intended for image acquisition, not an algorithm.
7. The Type of Ground Truth Used
- For Biocompatibility, Electrical Safety, EMC, Surface Heating, and SAR, the ground truth is established by adherence to recognized international and national standards (ISO, AAMI/ANSI, IEC, NEMA).
- For Bench Performance (SNR & Uniformity), the ground truth is established by conformity to predetermined acceptance criteria based on NEMA standards.
- For Clinical Performance (Diagnostic Quality Images), the ground truth is implied by subjective assessment of "diagnostic quality images" that "can be interpreted by a trained physician." This suggests an expert consensus or qualitative review of image characteristics deemed suitable for diagnosis, rather than a definitive "ground truth" derived from pathology or clinical outcomes.
8. The Sample Size for the Training Set
- This device is an MRI coil, not an AI or machine learning algorithm that requires a training set in the conventional sense. Therefore, the concept of a training set sample size is not applicable.
9. How the Ground Truth for the Training Set Was Established
- As the device is an MRI coil and not an AI algorithm, a training set is not applicable, and thus no ground truth establishment for a training set was performed.
§ 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.