DETECTION OF COLORECTAL POLYPS WITH CT COLOGRAPHY - INITIAL ASSESSMENT OF SENSITIVITY AND SPECIFICITY

PURPOSE: To estimate the sensitivity and specificity of computed tomog raphic (CT) colography in detection of colorectal polyps and to compar e these findings with those at axial CT. MATERIALS AND METHODS: In 70 consecutive patients, CT colography and colonoscopy were performed. He lical axial CT images and CT colographic images (multiplanar two- and three-dimensional endoluminal images) were evaluated separately by two radiologists blinded to results from colonoscopy and other imaging st udies. Findings were compared with those at colonoscopy, which was the standard. RESULTS: The sensitivity and specificity for the two observ ers with CT colography averaged 75% and 90% in patients with adenomas 10 mm in diameter or larger, 66% and 63% in patients with adenomas 5 m m in diameter or greater, and 45% and 80% for patients with adenomas l ess than 5 mm in diameter, respectively. Sensitivity and specificity w ith axial CT were lower than those with CT colography (58% and 74%, re spectively) in patients with adenomas 10 mm in diameter or larger. CON CLUSION: Compared with axial CT, CT colography appears to have superio r sensitivity and specificity in detection of clinically important col orectal adenomas. Early performance of CT colography seems promising f or detection of colorectal polyps 5 mm and larger.