(89 days)
iCAC is a software device intended for use in estimating presence and quantity of coronary artery calcium for patients aged 30 years and above during routine care. The device automatically analyzes non-contrast chest computed tomography (CT) images collected during routine care and outputs a visual representation of estimated coronary artery calcium segmentation (intended for informational purposes only) and both exact and four-category quantitative estimates of the patient's coronary artery calcium burden in Agatston units.
The output of the subject device is made available to the physician on-demand as part of his or her standard workflow. The device-generated calcium score or score group can be viewed in the patient report at the discretion of the physician, and the physician also has the option of viewing the device-generated calcium segmentation in a diagnostic image viewer. The subject device output in no way replaces the original patient report or the original chest CT scan: both are still available to be viewed and used at the discretion of the physician.
The device is intended to provide information to the physician to provide assistance during review of the patient's case. Results of the subject device are not intended to be used on a stand-alone basis and are solely intended to aid and provide information to the physician. In all cases, further action taken on a patient should only come at the recommendation of the physician after further reviewing the patient's results.
The iCAC Device (or the "subject device") is a standalone software as a medical device (SaMD) that provides adjunctive information to a radiologist for an estimate assessment of the presence and quantity of coronary artery calcium (CAC) from routine, non-contrast, non-gated chest computed tomography (CT) scans. The device can be used to leverage the high utilization of non-gated chest CT scans (from lung cancer screening programs, routine exams, etc.) to opportunistically identify and quantify coronary artery calcium in patients.
The iCAC Device takes as an input non-contrast, non-gated chest CT scans via DICOM transfer from the clinicians imaging database such as PACS or DICOM router. The device uses a deeplearning-based computer vision algorithm for its assessment. It estimates the presence and quantity of coronary artery calcium (CAC) from routine, non-contrast, non-gated chest computed tomography (CT) scans. iCAC Device can be used to leverage the high utilization of non-gated chest CT scans (from lung cancer screening programs, routine exams, etc.) to opportunistically identify and quantify coronary artery calcium in patients.
Here's an analysis of the acceptance criteria and the study proving the iCAC device's performance, based on the provided FDA 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance (iCAC Device) |
|---|---|
| Overall alignment between device output calcium score groups and ground truth calcium score groups ≥ 73% | 79.7% |
| Positive Predictive Value (PPV) for each of the four possible calcium score groupings ≥ 65% | 68.1% to 90.1% |
2. Sample Size and Data Provenance for the Test Set
- Sample Size: 762 paired CT studies.
- Data Provenance:
- Country of Origin: Not explicitly stated, but the data was collected from "nine (9) geographically diverse sites."
- Retrospective or Prospective: Retrospective study.
- Data Type: Each pair consisted of one non-gated, non-contrast chest CT and one gated coronary CT.
3. Number of Experts and Qualifications for Ground Truth Establishment (Test Set)
The document does not explicitly state the number or qualifications of experts used to establish the ground truth for the test set. It mentions "established ground truth" and "ground truth coronary calcium detection category" but provides no details on how this ground truth was determined (e.g., by human readers and their qualifications).
4. Adjudication Method for the Test Set
The document does not specify any adjudication method used for the test set (e.g., 2+1, 3+1).
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not reported. The study focused on the standalone performance of the iCAC device against an established ground truth. Therefore, there is no information on how human readers improve with or without AI assistance.
6. Standalone (Algorithm Only) Performance Study
Yes, a standalone performance study was conducted. The document states: "The iCAC Device performance was validated in a stand-alone retrospective study for overall agreement of the device output compared to the established ground truth."
7. Type of Ground Truth Used
The ground truth was based on a "gated coronary CT" in each paired study, which was then used to determine the "ground truth coronary calcium detection category." While not explicitly stated as "expert consensus" or "pathology," the inclusion of gated coronary CT implies a more definitive and often clinically established method for quantifying coronary artery calcium, likely interpreted by medical professionals. The document refers to it as "established ground truth."
8. Sample Size for the Training Set
The document does not provide the sample size used for the training set. It only details the test set for validation.
9. How Ground Truth for the Training Set Was Established
The document does not provide information on how the ground truth for the training set was established.
§ 892.1750 Computed tomography x-ray system.
(a)
Identification. A computed tomography x-ray system is a diagnostic x-ray system intended to produce cross-sectional images of the body by computer reconstruction of x-ray transmission data from the same axial plane taken at different angles. This generic type of device may include signal analysis and display equipment, patient and equipment supports, component parts, and accessories.(b)
Classification. Class II.