Introduction
CT colonography uses low dose CT with bowel preparation and insufflation to detect polyps and colorectal cancer. It provides a minimally invasive alternative to optical colonoscopy for screening and surveillance. Proper technique and standardized reporting are essential for diagnostic accuracy.
Preparation and Acquisition
Bowel cleansing and fecal tagging improve lesion conspicuity and reduce false positives. Dual position scanning prone and supine enhances polyp detection and reduces residual fluid artifacts. Low dose acquisition with thin slice reconstruction balances radiation safety and image quality.
Interpretation and Management
Radiologists review both 2D and 3D endoluminal reconstructions and report polyp size morphology and location using standardized lexicons. Lesions meeting size thresholds are referred for optical colonoscopy for removal and histology. Clear communication of limitations and follow up recommendations is important for patient care.
Program Considerations
CT colonography programs require coordination with endoscopy services for timely follow up of positive findings. Quality assurance includes polyp detection rates and correlation with colonoscopy outcomes. Patient selection and shared decision making support appropriate use.