(71 days)
The AIRIS II Magnetic Resonance Diagnostic Device with the CTL Phased Array Coil P/N MR-CTL-51 provides for continuous imaging of the cervical, thoracic, and lumbar spine and adjacent anatomies.
The MR 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.
Aids in the performance of minimally invasive, diagnostic, and therapeutic procedures of the head, body and extremities which may be facilitated by real-time MR guidance. Such procedures must be performed with MRI-compatible instrumentation, as selected and evaluated by the clinical user.
The AIRIS II MRI Magnetic Resonance Diagnostic Device is being enhanced by one additional RF Coil (CTL Phased Array Coil) to increase the clinical utility of the AIRIS II in the stationary configuration.
The CTL Phased Array Coil P/N MR-CTL-51 provides for continuous imaging of the cervical, thoracic, and lumbar spine and adjacent anatomies, and utilizes a proprietary multiple receiver coil configuration (8 elements) operating in the phased array mode. The coil operates in three modes: C, T/L, and L. A multi-position switch is used to select between the modes, by routing a current through PIN diode-activated high impedance tanks.
The C-spine section of the coil is nearly identical in design to the USAI QD C-spine coil P/N MR-QCS-51, and features a removable nosepiece bridge. The T/L and L sections are combinations of flat elements in the coil's base and removable loop sections, connecting to mounting blocks at the edge of the coil.
AIRIS II software did not need to be revised in order to support full functionality of this CTL Phased Array Coil.
The provided document, K994378, describes a 510(k) submission for an "Additional RF Coil for AIRIS II (CTL Phased Array)" and does not contain detailed information about acceptance criteria or a specific study proving the device meets acceptance criteria in the manner typically seen for AI/ML-based medical devices.
Instead, this submission is for a hardware enhancement (a new RF coil) for an existing Magnetic Resonance (MR) diagnostic device. The regulatory review process for such a device at the time (late 1990s) focused on demonstrating substantial equivalence to a predicate device, primarily through technical specifications, functional descriptions, and indications for use, rather than extensive performance studies with acceptance criteria as one might expect for a diagnostic or AI-driven software.
Based on the provided text, here's what can be extracted and what information is not present:
Missing Information:
- A table of acceptance criteria and reported device performance.
- Sample sizes, data provenance, number of experts, adjudication methods, MRMC studies, standalone AI performance, or how ground truth was established for a performance study. These types of studies are not described because this submission is not for a new diagnostic algorithm.
Information Extracted from the Document:
-
A table of acceptance criteria and the reported device performance:
- This document does not provide a table of acceptance criteria or reported device performance in the context of diagnostic accuracy, sensitivity, or specificity.
- The "performance" described is related to the physical and functional characteristics of the new RF coil and its compatibility with the existing AIRIS II MRI system.
- The submission focuses on demonstrating that the new CTL Phased Array Coil, when added to the AIRIS II, still functions as an MR diagnostic device and provides continuous imaging of the cervical, thoracic, and lumbar spine and adjacent anatomies, similar to the predicate device and the existing AIRIS II capabilities. The performance is implied by its ability to perform these imaging tasks.
-
Sample size used for the test set and the data provenance:
- Not applicable. This is a hardware modification (RF coil) for an existing MRI system. The document does not describe a "test set" of patient data for evaluating a diagnostic algorithm.
- The "testing" mentioned would be related to engineering validation of the coil's electrical and mechanical performance, and its integration with the MRI system, not clinical diagnostic accuracy based on a patient dataset.
-
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable. This is not a study requiring expert ground truth for diagnostic accuracy.
-
Adjudication method for the test set:
- Not applicable.
-
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 a hardware component for an MRI system, not an AI/ML-based diagnostic aid.
-
If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Not applicable. This is a hardware component, not a standalone algorithm.
-
The type of ground truth used:
- Not applicable.
-
The sample size for the training set:
- Not applicable. This is a hardware component, not an AI/ML system requiring a training set.
-
How the ground truth for the training set was established:
- Not applicable.
Summary based on the K994378 document:
The K994378 submission for the CTL Phased Array Coil for the AIRIS II MRI system is a 510(k) Pre-market Notification seeking to demonstrate substantial equivalence to a previously cleared device (the Hitachi AIRIS II, K974212 and the USAI QD C-spine coil P/N MR-QCS-51).
The "study" for this type of submission is essentially the demonstration that the new coil performs its intended function (providing continuous imaging of the cervical, thoracic, and lumbar spine and adjacent anatomies) and integrates seamlessly with the existing AIRIS II system without altering its fundamental scientific concepts, physical, or performance characteristics in a way that would raise new questions of safety or effectiveness.
The document implicitly "proves the device meets acceptance criteria" by stating its technological characteristics are "Identical to the Predicate Device" (Section 5.0) and describing its function as an enhancement that "provides for continuous imaging of the cervical, thoracic, and lumbar spine and adjacent anatomies," which aligns with the predicate device's capabilities. The FDA's clearance letter (MAR - 7 2000) confirms that the agency found the device "substantially equivalent" for its stated indications for use, thereby implicitly accepting that it meets the necessary criteria for safe and effective operation as an MRI coil.
§ 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.