[Application of CT colonography in diagnosis of colonic polyps].
OBJECTIVE
To assess the clinical values of CT colonography (CTC) in the diagnosis of colonic polyps.


METHODS
Forty-two patients who were clinically suspicious of colonic polyps or underwent colonic polyps screening received both CTC and conventional colonoscopy. Sixteen or 64-slice spiral CT and professional imaging processing techniques were used for evaluation. Per-polyp and per-patient results were analyzed. Those by per-polyp were subsequently divided into > or = 10 mm group, 5-10 mm group, and < or = 5 mm group. Sensitivity, positive predictive value (PPV), specificity, negative predictive value (NPV), and accuracy were calculated using statistical method for diagnostic studies, with conventional colonoscopy as a gold standard.


RESULTS
Ninety and 61 polyps were found by CTC and conventional colonoscopy, respectively. Sensitivity and PPV were 80.3%/55.6% by per-polyp and 100%/92.9%, 93.8%/65.2%, and 68.8%/ 41.5% in the > or = 10 mm group, 5-10 mm group, and < or = 5 mm group, respectively. Sensitivity, PPV, specificity, NPV, and accuracy by per-patient were 97.1%, 89.5%, 42.9%, 75.0%, and 88.1%, respectively.


CONCLUSIONS
CTC can clearly reveal the morphology of colonic polyps and can be used as a routine monitoring method for the clinical diagnosis of polyps.
Department of Radiology, PUMC Hospital, CAMS and PUMC, Beijing 100730, China. pwd3193@sina.com
Wei-dong
WD
Pan
Ming-wei
MW
Qin
Hua-dan
HD
Xue
Xiao-hong
XH
Liu
Jia-ming
JM
Qian
Ai-ming
AM
Yang
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003111:Colonic Polyps / Q000000981:diagnostic imaging*; D023881:Colonography, Computed Tomographic / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity