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Published on: August 1, 2019
Effect of computer-aided detection for CT colonography in a multireader, multicase trial
Abraham H Dachman1, Nancy A Obuchowski, Jeffrey W Hoffmeister
1Department of Radiology, MC2026, the University of Chicago, Chicago, IL 60637, USA. ahdachma@uchicago.edu
Computer-aided detection (CAD) significantly improved reader accuracy in interpreting computed tomographic (CT) colonographic images. This technology enhanced sensitivity for detecting polyps, especially smaller ones, with a slight decrease in specificity.
Area of Science:
- Radiology and Medical Imaging
- Artificial Intelligence in Healthcare
- Gastrointestinal Diagnostics
Background:
- Computed tomographic (CT) colonography is a crucial tool for colorectal cancer screening.
- Interpreting CT colonography images can be challenging, requiring high reader accuracy.
- Computer-aided detection (CAD) systems aim to assist radiologists in image interpretation.
Purpose of the Study:
- To evaluate the impact of computer-aided detection (CAD) in second-read mode on radiologist accuracy.
- To assess CAD's effectiveness in interpreting computed tomographic (CT) colonographic images.
- To determine if CAD improves polyp detection rates and overall diagnostic performance.
Main Methods:
- A HIPAA-compliant study involving 100 colonoscopy-proved cases (52 positive for polyps, 48 negative).
- Nineteen blinded readers interpreted cases twice: once without CAD and once with CAD assistance.
- Segment-level and patient-level receiver operating characteristic (ROC) curve analyses were used to assess CAD's effect.
Main Results:
- Reader accuracy, measured by segment-level area under the ROC curve (AUC), significantly improved with CAD (0.758 with CAD vs. 0.737 without, P = .015).
- Sensitivity for detecting polyps 6 mm or larger increased across per-segment, per-patient, and per-polyp analyses with CAD.
- Sensitivity for large polyps (≥10 mm) and small adenomas also improved with CAD, though specificity slightly decreased (by 0.025, P = .05).
Conclusions:
- Computer-aided detection (CAD) significantly enhances radiologist performance in CT colonography interpretation.
- CAD improves sensitivity for detecting polyps of various sizes, including small adenomas.
- While CAD offers substantial benefits in detection, a minor reduction in specificity was observed.
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