(88 days)
Siemens developed Cardiac Tagging pulse sequences for the Magnetom Vision and Impact Systems to allow for the non-invasive evaluation of cardiac wall motion and blood flow. Absence of tag deformation throughout the cardiac cycle is an indicator of dysfunctional myocardium which accompanies a variety of disease states. In addition, Cardiac Tagging may assist in differentiating between fixed thrombus and slowly flowing blood. Cardiac Tagging is intended as an add-on to routine MR imaging examinations of the heart and great vessels. Tagging may provide additional diagnostic information, which in the hands of a qualified physician, can be useful in the diagnosis of disease.
The Magnetom Cardiac Tagging Techniques consist of software and sequences designed to apply a series of equally spaced saturation bands to generate a grid on a cardiac image, for use in cardiac evaluation.
Here's an analysis of the provided text regarding the cardiac tagging device's acceptance criteria and studies:
Summary of Device Acceptance Criteria and Performance:
The provided 510(k) submission does not explicitly state specific numerical acceptance criteria or detail a dedicated study proving the device meets those criteria in the way a modern regulatory submission would for a novel device.
Instead, the submission focuses on demonstrating substantial equivalence to a previously cleared device (Siemens Magnetom Cardiac Cine Techniques, K900889) and ensuring that the new Cardiac Tagging feature does not negatively impact the existing safety and performance levels of the base MR systems (Magnetom Vision and Impact).
Therefore, the "acceptance criteria" here are implicitly tied to the performance characteristics of the predicate device and the safety parameters outlined by the FDA for MR Diagnostic Devices.
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|
| Safety Parameters (Unchanged by Tagging Feature): | |
| - Static field strength | Unaffected by the modifications described within this notification. |
| - RF exposure | Unaffected by the modifications described within this notification. |
| Performance Levels (Unchanged by Tagging Feature): | |
| - High contrast spatial resolution | Unaffected by the modifications described within this notification. |
| - Slice thickness | Unaffected by the modifications described within this notification. |
| - Geometric distortion | Unaffected by the modifications described within this notification. |
| - SNR (Signal-to-Noise Ratio) | Unaffected by the modifications described within this notification. |
| - Image uniformity | Unaffected by the modifications described within this notification. |
| Functional Equivalence: | |
| - Non-invasive evaluation of cardiac wall motion and blood flow | The device is designed to "apply a series of equally spaced saturation bands to generate a grid on a cardiac image, for use in cardiac evaluation" and "allow for the non-invasive evaluation of cardiac wall motion and blood flow." It is deemed substantially equivalent to the predicate Siemens Magnetom Cardiac Cine Techniques (K900889), which presumably also offers non-invasive cardiac evaluation. |
| - Ability to identify dysfunctional myocardium | "Absence of tag deformation throughout the cardiac cycle is an indicator of dysfunctional myocardium which accompanies a variety of disease states." (Intended Use) |
| - Ability to differentiate fixed thrombus and flowing blood | "Cardiac Tagging may assist in differentiating between fixed thrombus and slowly flowing blood." (Intended Use) |
2. Sample Size Used for the Test Set and Data Provenance:
The provided document does not describe a specific clinical "test set" or a study with a defined sample size to demonstrate the de novo performance of the Cardiac Tagging feature. The submission relies on the concept of substantial equivalence to an already cleared device. There is no mention of country of origin or whether data was retrospective or prospective, as no new clinical study data is presented for this specific feature as a primary means of establishing safety and effectiveness.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
Not applicable, as no described test set with independently established ground truth is presented in this 510(k) summary.
4. Adjudication Method for the Test Set:
Not applicable, as no described test set requiring adjudication is presented.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
No MRMC study is mentioned. The submission does not describe a study comparing human readers with and without AI assistance for this device.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study:
Not explicitly described. The device is a "software and sequences designed to apply a series of equally spaced saturation bands to generate a grid on a cardiac image." While it performs an automated function, its "performance" is assessed in terms of its impact on the overall MR system's safety and fundamental image characteristics, and its intended use is to provide "additional diagnostic information, which in the hands of a qualified physician, can be useful in the diagnosis of disease." This implies it's an adjunct, not a standalone diagnostic.
7. Type of Ground Truth Used:
Not applicable, as no dedicated clinical study with independent ground truth is described for the Cardiac Tagging feature itself. The ground truth for the substantial equivalence argument is the established safety and effectiveness of the predicate device and the general regulatory standards for MR devices.
8. Sample Size for the Training Set:
Not applicable. This document describes a software feature for an MR system, not a machine learning or AI model in the modern sense that would require a distinct "training set" for model development. The software "applies a series of equally spaced saturation bands" and presumably follows deterministic algorithms, not learned patterns.
9. How the Ground Truth for the Training Set Was Established:
Not applicable, as there is no described training set.
In summary, this 510(k) submission primarily leverages the concept of substantial equivalence rather than presenting new clinical performance data for the Cardiac Tagging feature. The "acceptance criteria" are the established safety and performance levels of the core MR system and the predicate device, which the new feature is stated not to degrade.
§ 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.