(59 days)
The SIGNA Hero 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 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, TMI, spine, 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 SIGNA Hero reflect the spatial distribution or molecular environment of nuclei exhibiting magnetic resonance. These images and/or spectra when interpreted by a trained physician vield information that may assist in diagnosis.
SIGNA™ Hero is a whole body magnetic resonance scanner designed to support high resolution, high signal to-noise ratio, and short scan times. The systems use a combination of time-varying magnet 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 oblique planes, using various pulse sequences, imaging techniques and reconstruction algorithms. The system features a 3.0T superconducting magnet with 70cm bore size. The system is designed to conform to NEMA DICOM standards (Digital Imaging and Communications in Medicine).
The provided text describes information about the GE Healthcare SIGNA Hero MRI system (K213668). However, it does not contain details about specific acceptance criteria related to a specific diagnostic task (like detecting a particular disease), nor does it describe a study specifically designed to prove that the device meets such criteria for a diagnostic algorithm.
Instead, the document focuses on demonstrating substantial equivalence of the SIGNA Hero to its predicate device, the SIGNA Pioneer (K160621), as per FDA 510(k) premarket notification requirements.
Here's an analysis based on the provided text, addressing the requested points where information is available:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not provide a table of acceptance criteria for a specific diagnostic task or algorithm performance metrics (e.g., sensitivity, specificity, AUC). Instead, it states that the device was tested against safety and performance standards to demonstrate substantial equivalence to the predicate device.
Acceptance Criteria (General for MRI System Substantial Equivalence):
- Compliance with voluntary standards (ANSI/AAMI ES60601-1, IEC 60601-1-2, IEC 60601-2-33, IEC 62304, ISO 10993-1, IEC 62464-1).
- Compliance with NEMA standards (MS 3, MS 4, MS 8, PS3 for DICOM).
- Successful biocompatibility track record (ISO 10993-1 testing and history of patient contacting materials).
- Acceptable diagnostic image performance comparable to the predicate device in accordance with FDA Guidance "Submission of Premarket Notifications for Magnetic Resonance Diagnostic Devices."
Reported Device Performance:
- The SIGNA Hero and predicate device were subject to similar risk management testing.
- The SIGNA Hero complies with all listed standards.
- The SIGNA Hero has a successful biocompatibility track record.
- "The image quality of the SIGNA™ Hero is substantially equivalent to that of the predicate device."
- "The sample clinical images demonstrate acceptable diagnostic image performance of the SIGNA™ Hero..."
- The device performs as intended based on non-clinical tests.
2. Sample Size Used for the Test Set and Data Provenance
The document mentions "sample clinical images" were included to demonstrate acceptable diagnostic image performance. However, it does not specify:
- The exact sample size of these clinical images.
- The provenance of the data (e.g., country of origin, retrospective or prospective).
3. Number of Experts Used to Establish Ground Truth and Qualifications
The document states that images are "interpreted by a trained physician" but does not specify:
- The number of experts involved in reviewing the "sample clinical images."
- The specific qualifications of these experts (e.g., radiologists with certain years of experience).
4. Adjudication Method for the Test Set
The document does not mention any adjudication method (e.g., 2+1, 3+1, none) for establishing ground truth or evaluating the clinical images.
5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was Done
No, the document explicitly states: "The subject of this premarket submission, the SIGNA™ Hero, did not require clinical studies to support substantial equivalence." Therefore, an MRMC study comparing human readers with and without AI assistance was not performed or detailed in this submission.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
This submission is for an MRI scanner, not a specific diagnostic algorithm or AI software. Therefore, the concept of "standalone performance" for an algorithm isn't directly applicable in the context of this document. The performance evaluation focuses on the image quality and safety of the MR system itself.
7. The Type of Ground Truth Used
For the "sample clinical images," the ground truth implicitly refers to the interpretation by a trained physician regarding the diagnostic image performance. Beyond this, for the system's overall performance and safety, ground truth is established through compliance with established industry standards and recognized risk management practices.
8. The Sample Size for the Training Set
The document describes the submission of an MR scanner, not an AI/ML algorithm that requires a distinct training set. Hence, there is no mention of a training set sample size.
9. How the Ground Truth for the Training Set was Established
As there is no mention of an algorithm or training set, this information is 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.