(24 days)
The Caption Guidance software is intended to assist medical professionals in the acquisition of cardiac ultrasound images. The Caption Guidance software is an accessory to compatible general purpose diagnostic ultrasound systems.
The Caption Guidance software is indicated for use in two-dimensional transthoracic echocardiography (2D-TTE) for adult patients, specifically in the acquisition of the following standard views: Parasternal Long-Axis (PLAX), Parasternal Short-Axis at the Aortic Valve (PSAX-AV), Parasternal Short-Axis at the Mitral Valve (PSAX-MV), Parasternal Short-Axis at the Papillary Muscle (PSAX-PM), Apical 4-Chamber (AP4), Apical 5-Chamber (AP5), Apical 2-Chamber (AP2), Apical 3-Chamber (AP3), Subcostal 4-Chamber (SubC4), and Subcostal Inferior Vena Cava (SC-IVC).
The Caption Guidance software is a radiological computer assisted acquisition guidance system that provides real-time user guidance during acquisition of echocardiography to assist the user in obtaining anatomically correct images that represent standard 2D echocardiographic diagnostic views and orientations. Caption Guidance is a software-only device that uses artificial intelligence to emulate the expertise of sonographers.
Caption Guidance is comprised of several different features that, combined, provide expert guidance to the user. These include:
- Quality Meter: The real-time feedback from the Quality Meter advises the user on the expected diagnostic quality of the resulting clip, such that the user can make decisions to further optimize the quality, for example by following the prescriptive guidance feature below.
- Prescriptive Guidance: The prescriptive guidance feature in Caption Guidance provides direction to the user to emulate how a sonographer would manipulate the transducer to acquire the optimal view.
- Auto-Capture: The Caption Guidance Auto-Capture feature triggers an automatic capture of a clip when the quality is predicted to be diagnostic, emulating the way in which a sonographer knows when an image is of sufficient quality to be diagnostic and records it.
- Save Best Clip: This feature continually assesses clip quality while the user is scanning and, in the event that the user is not able to obtain a clip sufficient for Auto-Capture, the software allows the user to retrospectively record the highest quality clip obtained so far, mimicking the choice a sonographer might make when recording an exam.
The provided text describes the Caption Guidance software, an updated version of a previously cleared device. The submission focuses on demonstrating substantial equivalence to its predicate device rather than presenting a new clinical study with specific acceptance criteria and performance metrics for the updated features in a comparative effectiveness study.
Therefore, the information for some of your requested points is not explicitly detailed in the provided text, as the submission relies on demonstrating that the modifications to the device do not raise new questions of safety or effectiveness and that the overall functionality remains substantially equivalent to the predicate.
Here's a breakdown of the information available based on your request:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state a table of specific acceptance criteria with numerical targets for the reported device performance related to the updated features of Caption Guidance (e.g., a specific recall or precision for Auto-Capture). Instead, it describes general performance testing and verification activities to ensure the software performs as expected and is substantially equivalent to the predicate.
The "Performance Data" section details that:
- "Extensive algorithm development and software verification testing assessed the performance of the software."
- "The Caption Guidance algorithm was tested for the performance of the modified Auto-Capture feature in recording clinically-acceptable images and clips."
- "Furthermore, the subject device's algorithm was tested for the performance of providing Prescriptive Guidance (PG), using the following tasks:
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- Frame-level PG prediction of the probe maneuver needed to acquire an image/frame of heart, for a specific view.
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- Clip-level PG prediction of the probe maneuver needed to acquire a diagnostic quality clip for a specific view."
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The conclusion is that "Overall, the non-clinical performance testing results provide evidence in support of the functionality of Caption Guidance fundamental algorithms."
For Human Factors Testing, the results conclude:
- "Summative testing has been completed with 16 users without prior scanning experience and 9 users with prior experience)."
- "The summative human factors testing concluded that there were no use errors associated with critical tasks likely to lead to patient injury."
- "Additionally, although the testing was not comparative in nature, when viewed in context of the testing provided in the original De Novo, the enhanced product appears to provide optimization of usability."
2. Sample Size Used for the Test Set and Data Provenance
The document does not specify a separate "test set" sample size for evaluating clinical performance in the traditional sense for this 510(k) submission. The focus was on software verification and validation, and human factors testing.
- Human Factors Testing:
- Sample Size: 16 users without prior scanning experience and 9 users with prior experience (total 25 users).
- Data Provenance: Not explicitly stated (e.g., country of origin, retrospective/prospective). This was likely prospective testing conducted with study participants.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
This information is not provided in the document. As the submission focuses on software verification and human factors for an updated version of a device, the establishment of ground truth by multiple experts for a clinical "test set" in the context of diagnostic accuracy is not detailed for this specific submission. The initial De Novo submission (DEN190040) would likely contain this information for the predicate device.
4. Adjudication Method for the Test Set
This information is not provided in the document.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size
A formal multi-reader multi-case (MRMC) comparative effectiveness study was not done for this 510(k) submission. The document explicitly states for the human factors testing: "although the testing was not comparative in nature...". The comparison is mainly against the predicate device's established performance and the demonstration that the enhancements do not introduce new risks or diminish performance.
6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done
The document states: "Extensive algorithm development and software verification testing assessed the performance of the software." and "The Caption Guidance algorithm was tested for the performance of the modified Auto-Capture feature... Additionally, the subject device's algorithm was tested for the performance of providing Prescriptive Guidance (PG)..."
This indicates that standalone algorithm performance testing was conducted for the Auto-Capture and Prescriptive Guidance features. However, specific metrics (e.g., accuracy, sensitivity, specificity) for this standalone performance are not provided. The human factors testing then evaluates the human-in-the-loop performance of the entire system.
7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.)
For the algorithm testing of Auto-Capture and Prescriptive Guidance, the ground truth would likely be based on:
- Expert Consensus/Clinical Acceptability: For Auto-Capture, the "recording clinically-acceptable images and clips" implies expert assessment of image quality.
- Expert Knowledge of Optimal Probe Maneuvers: For Prescriptive Guidance, the ground truth for "probe maneuver needed to acquire an image/frame of heart" or "diagnostic quality clip" would stem from expert sonographer knowledge and established echocardiography guidelines.
The document does not explicitly state the methodology for establishing this ground truth (e.g., specific number of sonographers or cardiologists, their qualifications).
8. The Sample Size for the Training Set
The document does not provide a specific sample size for the training set used for the Caption Guidance algorithms. It mentions "Extensive algorithm development..." but does not detail the training data sets.
9. How the Ground Truth for the Training Set Was Established
The document does not explicitly describe how the ground truth for the training set was established. However, given the nature of the device (guidance for cardiac ultrasound acquisition), it would typically involve:
- Expert Sonographer/Cardiologist Annotation: Labeling of optimal probe positions, image quality assessments, and identification of standard views in echocardiogram clips.
- Adherence to Clinical Guidelines: Ensuring annotations align with established protocols for acquiring diagnostic quality echocardiograms.
892.2100 Radiological acquisition and/or optimization guidance system.
892.2100 Radiological acquisition and/or optimization guidance system.
(a)
Identification. A radiological acquisition and/or optimization guidance system is a device that is intended to aid in the acquisition and/or optimization of images and/or diagnostic signals. The device interfaces with the acquisition system, analyzes its output, and provides guidance and/or feedback to the operator for improving image and/or signal quality.(b)
Classification. Class II (special controls). The special controls for this device are:(1) Design verification and validation must include:
(i) A detailed, technical device description, including a detailed description of the impact of any software and hardware on the device's functions, the associated capabilities and limitations of each part, and the associated inputs and outputs.
(ii) A detailed, technical report on the non-clinical performance testing of the subject device in the intended use environments, using relevant consensus standards when applicable.
(iii) A detailed report on the clinical performance testing, obtained from either clinical testing, accepted virtual/physical systems designed to capture clinical variability, comparison to a closely-related device with established clinical performance, or other sources that are justified appropriately. The choice of the method must be justified given the risk of the device and the general acceptance of the test methods. The report must include the following:
(A) A thorough description of the testing protocol(s).
(B) A thorough, quantitative evaluation of the diagnostic utility and quality of images/data acquired, or optimized, using the device.
(C) A thorough, quantitative evaluation of the performance in a representative user population and patient population, under anticipated conditions and environments of use.
(D) A thorough discussion on the generalizability of the clinical performance testing results.
(E) A thorough discussion on use-related risk analysis/human factors data.
(iv) A detailed protocol that describes, in the event of a future change, the level of change in the device technical specifications or indications for use at which the change or changes could significantly affect the safety or effectiveness of the device and the risks posed by these changes. The assessment metrics, acceptance criteria, and analytical methods used for the performance testing of changes that are within the scope of the protocol must be included.
(v) Documentation of an appropriate training program, including instructions on how to acquire and process quality images and video clips, and a report on usability testing demonstrating the effectiveness of that training program on user performance, including acquiring and processing quality images.
(2) The labeling required under § 801.109(c) of this chapter must include:
(i) A detailed description of the device, including information on all required and/or compatible parts.
(ii) A detailed description of the patient population for which the device is indicated for use.
(iii) A detailed description of the intended user population, and the recommended user training.
(iv) Detailed instructions for use, including the information provided in the training program used to meet the requirements of paragraph (b)(1)(iv) of this section.
(v) A warning that the images and data acquired using the device are to be interpreted only by qualified medical professionals.
(vi) A detailed summary of the reports required under paragraphs (b)(1)(ii) and (iii) of this section.
(vii) A statement on upholding the As Low As Reasonably Achievable (ALARA) principle with a discussion on the associated device controls/options.