(67 days)
The intended use of Quantitative Flow is to non-invasively obtain and map quantitative flow and velocity measurements from a vessel during a cardiac cycle using the principles of NMR.
Picker's Quantitative Flow functionality includes the ability to create reference magnitude, phase velocity, phase contrast, phase contrast velocity and reference magnitude velocity images. The operator can define up to eight regions of interest on the phase velocity images and perform several quantitative measurements. When combined with cardiac gating, the operator can observe changes in velocity and flow throughout the cardiac cycle.
Here's a breakdown of the acceptance criteria and study information for the Quantitative Flow device, based on the provided text:
Acceptance Criteria and Device Performance
| Acceptance Criteria (Predicate Device K924605) | Reported Device Performance (Quantitative Flow) |
|---|---|
| Accuracy of Flow Measurements: In vivo testing demonstrated that flow could be measured to within 5.26% ± 3.77 for constant flow. | Accuracy of Flow Measurements: In vivo testing demonstrated that flow could be measured to within 3.9% ± 0.8 for constant flow. |
| Accuracy of Flow Measurements: In vivo testing demonstrated that flow could be measured to within 5.73% ± 3.0 for pulsatile flow. | Accuracy of Flow Measurements: In vivo testing demonstrated that flow could be measured to within 3.5% ± 2.2 for pulsatile flow. |
| Range of Velocities: Approx. 20-400 cm/sec | Range of Velocities: 5-600 cm/sec |
Note on meeting criteria: The Quantitative Flow device exceeds the accuracy of flow measurements demonstrated by the predicate device for both constant and pulsatile flow. It also offers a wider range of measurable velocities. This "better" performance is what contributes to the substantial equivalence determination.
Study Information:
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Sample size used for the test set and the data provenance:
- The document states "In vivo testing demonstrated...", implying human or animal subjects, but does not specify the sample size for this in vivo testing.
- Data Provenance: Not specified (e.g., country of origin, retrospective or prospective).
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not specified. The document mentions "In vivo testing" but does not elaborate on how ground truth was established or if experts were involved in defining it for the test results reported.
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Adjudication method for the test set:
- Not specified.
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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. This was not an MRMC comparative effectiveness study. The comparison is between the new device's performance metrics and a predicate device's performance metrics, not human reader performance with and without AI assistance. The device is for quantitative flow measurement, not for interpretation by human readers that would be augmented by AI.
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If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- Yes, implicitly. The reported "Accuracy of Flow Measurements" are values obtained directly from the device's measurements in an in vivo setting, indicating standalone performance. The device is an MRI option for obtaining and mapping quantitative flow, suggesting algorithmic processing of MRI data to produce these measurements.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- Not explicitly stated, but implied to be a reference standard for flow measurement. For "in vivo testing," a common method for establishing ground truth for flow measurements would involve a highly accurate, independent measurement technique, or phantoms with known flow characteristics. However, the document only says "in vivo testing" without further detail on the ground truth generation.
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The sample size for the training set:
- Not specified. The document does not describe the development or training of the algorithm, only its performance.
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How the ground truth for the training set was established:
- Not specified. As the training set information is missing, the ground truth establishment for it is also not described.
§ 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.