(74 days)
The Emory Cardiac Toolbox™ 3.2 software program should be used for the quantification of myocardial perfusion for the display of wall motion and quantification of left-ventricular function parameters from gated Tc-99m SPECT & PET myocardial perfusion studies (EGS™), for the 3D alignment of coronary artery models from CT coronary angiography onto the left ventricular 3D epicardial surface, for the assessment of cardiac mechanic dyssynchrony using phase analysis, for generation of the short axis, vertical, and horizontal long axis tomograms from the SPECT raw data using either filtered backprojection (FBP) or iterative reconstruction (MLEM/OSEM), and for the quantitative analysis and display of SPECT AdreView™ (133)-mlBG) data sets used for evaluation of patients with congestive heart failure.
The product is intended for use by trained nuclear technicians and nuclear medicine or nuclear cardiology physicians. The clinician remains ultimately responsible for the final interpretation and diagnosis based on standard practices and visual interpretation of all SPECT and PET data.
The Emory Cardiac Toolbox™ 3.2 is used to display gated wall motion and for quantifying parameters of left-ventricular perfusion and function from gated SPECT & PET myocardial perfusion studies. These parameters are: perfusion, ejection fraction, end-diastolic volume, end-systolic volume, myocardial mass, transient ischemic dilatation (TID), and cardiac mechanic dyssynchrony. In addition, the program offers the capability of providing the following diagnostic information: computer assisted visual scoring, prognostic information, expert system image interpretation, and patient specific 3D coronary overlay. The program can also be used for the 3D alignment of coronary artery models from CT coronary angiography onto the left ventricular 3D epicardial surface and for generation of the short axis, vertical, and horizontal long axis tomograms from the SPECT raw data using either filtered backprojection (FBP) or iterative reconstruction (MLEM/OSEM). The Emory Cardiac Toolbox can be used with any of the following Myocardial SPECT Protocols: Same Day and Two Day Sestamibi, Dual-Isotope (Tc-99m/Tl-201), Tetrofosmin, and Thallium, Rubidium-82, N-13-ammonia, FDG protocols, and user defined normal databases. The program can also be used for the quantitative analysis and display of SPECT Adre\View™ (123)-mlBG) data sets. This program was developed to run in the IDL operating system environment which can be executed on any nuclear medicine computer systems which supports IDL and the Aladdin (General Electric) software development environment. The program processes the studies automatically, however, user verification of output is required and manual processing capability is provided.
Here's an analysis of the provided text to extract the acceptance criteria and study details:
1. Acceptance Criteria and Reported Device Performance
The document does not explicitly state acceptance criteria in a quantitative, pass/fail format for the new features of Emory Cardiac Toolbox™ 3.2. Instead, it relies on substantial equivalence to previous versions and validates the new AdreView™ analysis through its ability to differentiate abnormal and normal uptake.
| Feature/Metric | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Visual Scoring, Prognosis, Expert System, Coronary Fusion Algorithms | Successfully evaluated in their respective patient populations. | Successfully evaluated in 20, 504, 461, and 9 patients respectively. |
| Rb-82 Normal Limits | Development and validation successful. | Developed and validated in 176 patients. |
| PET tools for perfusion-metabolism match-mismatch | Successful evaluation. | Successfully completed in 90 patients. |
| N-13ammonia normal limits | Development and validation successful. | Developed and validated in 144 patients. |
| Alignment method for 3D CT coronary artery onto LV 3D epicardial surface | Successful validation using phantom and patient studies. | Validated using phantom and patient studies (n=8). |
| SPECT Reconstruction | Prospective validation. | Validated in 10 patients. |
| Phase analysis (SyncTool™) | Development and prospective validation. | Developed in 90 normal patients and prospectively validated in 75 additional patients. |
| SPECT AdreView™ (¹²³I-mIBG) Data Analysis (New in v3.2) | Capability to differentiate subjects with abnormal and normal AdreView™ uptake using the H/M ratio index. | Demonstrated the capability to differentiate subjects with abnormal and normal AdreView™ uptake using the H/M ratio index in a validation group of 1,016 patients. |
2. Sample Size and Data Provenance for the Test Set
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Sample Size for AdreView™ Validation: 1,016 patients
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Data Provenance for AdreView™ Validation: The document does not explicitly state the country of origin or whether cases were retrospective or prospective for the AdreView™ validation group. It only mentions "two groups of patients used in this study, a pilot group consisting of 67 patients... and a validation group consisting of 1,016 patients." The pilot group was "used to develop the heart volume regions of interest," implying a development set, while the 1,016 patients were specifically for validation.
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Other Sample Sizes Mentioned (for previous versions or other features):
- Initial program (v2.0) LV functional parameters: 217 patients (in-house), 80 patients (multicenter trial).
- Visual scoring: 20 patients
- Prognosis: 504 patients
- Expert system: 461 patients
- Coronary fusion algorithms: 9 patients
- Rb-82 normal limits: 176 patients
- PET tools (perfusion-metabolism): 90 patients
- N-13ammonia normal limits: 144 patients
- 3D CT coronary artery alignment: 8 patients
- SPECT reconstruction: 10 patients (prospective)
- Phase analysis (SyncTool™): 90 normal patients (development), 75 additional patients (prospective validation).
3. Number of Experts and Qualifications for Ground Truth
The document does not explicitly state the number of experts used to establish ground truth for the AdreView™ validation. For previous versions and other features, it refers to "standard visual analysis," "physician interpretation," and "expert system interpretation" but does not detail the number or specific qualifications of these experts.
4. Adjudication Method for the Test Set
The document does not describe a formal adjudication method (e.g., 2+1, 3+1) for establishing ground truth in the validation studies. The statement "The physician should integrate all of the patients' clinical and diagnostic information...prior to making his final interpretation" implies a physician-led decision process, but not a specific adjudication protocol involving multiple experts.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study demonstrating how much human readers improve with AI vs. without AI assistance is explicitly described for the new features in v3.2. The document focuses on the performance of the algorithm itself in differentiating normal/abnormal AdreView™ uptake, rather than the AI's assistance to human readers. The general statement about the program serving "merely as a display and processing program to aid in the diagnostic interpretation" suggests it's an assistive tool, but no study quantifies this assistance.
6. Standalone (Algorithm Only) Performance
Yes, a standalone performance evaluation was done for the new AdreView™ analysis. The study focused on the "capability to differentiate subjects with abnormal and normal AdreView™ uptake using the H/M ratio index" from the algorithm's output. This is a direct evaluation of the algorithm's performance on its own. Similarly, many of the performance evaluations for previous versions (e.g., calculation of LV functional parameters, Rb-82 normal limits, PET tools) appear to be standalone evaluations of the algorithm's output.
7. Type of Ground Truth Used
For the AdreView™ validation, the ground truth was implicitly derived from the clinical classification of patients into "abnormal and normal AdreView™ uptake." The document does not specify the exact methods for this classification (e.g., based on clinical diagnosis, follow-up, or a single expert's visual assessment). For earlier features, "standard visual analysis of the gated SPECT & PET study" and "physician interpretation" are mentioned, suggesting expert consensus or clinical diagnosis as the implicit ground truth.
8. Sample Size for the Training Set
- Pilot Group for AdreView™: 67 patients were used "to develop the heart volume regions of interest on the SPECT reconstructions." This functions as a development/training set for establishing parts of the algorithm.
- Other Development Sets:
- Phase analysis (SyncTool™): Developed in 90 normal patients.
- SPECT reconstruction: "development (phantom, animal, and patients n=4)".
- Rb-82 normal limits: 176 patients used for "development and validation."
- N-13ammonia normal limits: 144 patients used for "development and validation."
9. How Ground Truth for the Training Set Was Established
For the 67-patient pilot group for AdreView™ to "develop the heart volume regions of interest," the method for establishing ground truth is not specified. It likely involved expert input or established anatomical guidelines for defining these regions.
For the "development" portions of other features (e.g., 90 normal patients for SyncTool™ phase analysis, 4 patients/phantoms/animals for SPECT reconstruction development), the document doesn't detail how ground truth was explicitly established, but it would typically involve expert interpretation, phantoms with known properties, or histological/pathological correlation where applicable, though none are specifically stated here beyond the nature of the data itself (e.g., "normal patients" for SyncTool).
§ 892.1200 Emission computed tomography system.
(a)
Identification. An emission computed tomography system is a device intended to detect the location and distribution of gamma ray- and positron-emitting radionuclides in the body and produce cross-sectional images through computer reconstruction of the data. This generic type of device may include signal analysis and display equipment, patient and equipment supports, radionuclide anatomical markers, component parts, and accessories.(b)
Classification. Class II.