(189 days)
The ECHELON Oval MRI System is an imaging device, and is intended to provide the physician with physiological and clinical information, obtained non-invasively and without the use of ionizing radiation. The MR system produces transverse, coronal, sagittal, oblique, and curved cross-sectional images that display the internal structure of the head, body, or extremities. The images produced by the MR system reflect the spatial distribution of protons (hydrogen nuclei) exhibiting magnetic resonance. The NMR properties that determine the image appearance are proton density, spin-lattice relaxation time (T1), spin-spin relaxation time (T2), and flow. When interpreted by a trained physician, these images provide information that can be useful in diagnosis determination.
Anatomical Region: Head, Body, Spine, Extremities Nucleus excited: Proton Diagnostic uses: T1, T2, proton density weighted imaging Diffusion weighted imaging MR Angiography Image processing Spectroscopy Whole Body
The ECHELON OVAL is a Magnetic Resonance Imaging System that utilizes a 1.5 Tesla superconducting magnet in a gantry design. The design was based on the ECHELON MRI system. The ECHELON OVAL has been designed to enhance clinical utility as compared to the ECHELON by taking advantage of open architecture.
Here's an analysis of the provided text regarding the acceptance criteria and supporting studies for the ECHELON Oval MRI System:
Summary of Acceptance Criteria and Reported Device Performance
The ECHELON Oval MRI System is a Magnetic Resonance Imaging System that utilizes a 1.5 Tesla superconducting magnet. The submission focuses on demonstrating substantial equivalence to its predicate device, the ECHELON C Magnetic Resonance Imaging System (K083533), rather than setting specific independent performance acceptance criteria. The "acceptance criteria" are implicitly met by demonstrating that the new device performs at least as well as, and adheres to the same standards as, the predicate and relevant industry standards.
Therefore, the table below reflects the relevant standards and the nature of the "reported device performance" as demonstrating compliance.
| Acceptance Criteria (Standards/Tests) | Reported Device Performance (Compliance/Result) |
|---|---|
| Non-Clinical Testing: | Compliance Demonstrated: |
| NEMA MS 1, Determination of Signal-to-noise Ratio (SNR) in Diagnostic Magnetic Resonance Images | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| NEMA MS 2, Determination of Two-Dimensional Geometric Distortion in Diagnostic Magnetic Resonance Images | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| NEMA MS 3, Determination of Image Uniformity in Diagnostic Magnetic Resonance Images | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| NEMA MS 4, Acoustic Noise Measurement Procedure for Diagnostic Magnetic Resonance Imaging Devices | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| NEMA MS 5, Determination of Slice Thickness in Diagnostic Resonance Imaging | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| NEMA MS 7, Measurement Procedure for Time-Varying Gradient Fields (dB/dt) for Diagnostic Magnetic Resonance Imaging Devices | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| NEMA MS 8, Characterization of the Specific Absorption Rate for Magnetic Resonance Imaging Systems | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| IEC 60601-1, Medical Electrical Equipment Part 1: General Requirements for Safety | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| IEC 60601-1-1, Collateral Standard: Safety Requirements for Medical Electrical Systems | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| IEC 60601-1-2, Collateral standard: Electromagnetic compatibility - Requirements and tests | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| IEC 60601-1-4, Collateral Standard: Programmable electrical medical systems | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| IEC 60601-2-33, Particular requirements for the safety of magnetic resonance equipment for medical diagnosis | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. |
| IEC 62304, Medical device software - Software life cycle processes | ECHELON Oval was subjected to this test; reported findings allow for a conclusion of substantial equivalence. The software operating system was changed from Windows XP to Windows 7. |
| High Contrast Spatial Resolution | Additional laboratory testing performed; reported findings allow for a conclusion of substantial equivalence. |
| Estimation of the Ratio of Peak Local (10g average) SAR Values to Whole-Body SAR (numerical simulation) | Additional laboratory testing performed (numerical simulation); reported findings allow for a conclusion of substantial equivalence. The maximum RF power was increased from 20 kW to 40 kW, and the maximum output current of the gradient amplifier from 550 A to 700 A, necessitating this evaluation. |
| Clinical Testing: | Compliance Demonstrated: |
| Sample clinical imaging of the head, torso, and extremities using all anatomy coils (as specified in FDA MRI 510(k) guidance, 1998 November 14) | "The Echelon Oval submission includes sample clinical imaging of the head, torso, and extremities using all anatomy coils". This demonstrates the device's ability to produce diagnostically useful images across its intended anatomical regions, maintaining substantial equivalence to the predicate. |
Detailed Study Information:
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Sample size used for the test set and the data provenance:
- Test Set Sample Size: Not explicitly stated as a specific numerical count of patients or images for the clinical testing. The document states "sample clinical imaging of the head, torso, and extremities using all anatomy coils."
- Data Provenance: Not specified (e.g., country of origin). The testing seems to be conducted by Hitachi Medical Systems America, Inc., implying internal or contracted testing associated with USA operations. The clinical imaging is presented as "sample clinical imaging," which could be prospective or retrospective, but the document does not clarify. It does not appear to be a large-scale clinical trial in the traditional sense, but rather a demonstration of imaging capabilities.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This information is not provided in the given text. For an MRI system, the "ground truth" to determine image quality and diagnostic utility would typically involve expert interpretation (e.g., radiologists) comparing images to clinical findings or other diagnostic modalities, but details are absent. The document only states that images "provide information that can be useful in diagnosis determination" when "interpreted by a trained physician."
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Adjudication method for the test set:
- This information is not provided. Given the nature of the submission (demonstrating substantial equivalence through compliance with technical standards and providing "sample clinical imaging"), a formal adjudication method for a test set of diagnosable cases is not described.
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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:
- No, an MRMC comparative effectiveness study was not done. This submission is for an MRI system, not an AI-powered diagnostic tool. The purpose is to demonstrate the system's ability to produce high-quality diagnostic images, substantially equivalent to a predicate MRI system. There is no mention of AI assistance or human reader performance improvement.
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If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- No, a standalone algorithm performance study was not done. This device is an MRI system, not an algorithm, and is intended to be interpreted by a human physician ("When interpreted by a trained physician").
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- For the non-clinical (phantom) tests, the "ground truth" is derived from the established physical properties and measurements required by the NEMA and IEC standards (e.g., actual SNR values, known dimensions for geometric distortion, etc.).
- For the "sample clinical imaging," the specific "ground truth" method for evaluating diagnostic utility is not explicitly stated. It can be inferred that expert interpretation of images relative to established medical knowledge or other clinical data served as an implicit "ground truth," but the document does not detail this process.
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The sample size for the training set:
- This information is not applicable/not provided. The device is an MRI hardware system, not a machine learning algorithm that requires a "training set" in the traditional sense. The software operating system was updated, but the core image reconstruction and processing capabilities are stated to be "identical to the predicate device" in terms of "base elements of the system software."
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How the ground truth for the training set was established:
- This information is not applicable/not provided as there is no mention of a training set for an AI algorithm.
§ 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.