[Diagnostic efficiency of multislice computed tomography colonography in the detection of colorectal tumors: comparison with conventional colonography].

Purpose: To evaluate the diagnostic efficiency of multislice CT colonography in the detection of colorectal tumors by comparing it with conventional colonography in patients with high risk of colorectal cancer.
Materials and Methods: Thirty-seven patients who had undergone conventional colonoscopy because of a suspicion of colorectal cancer were scanned with a four-detector multislice CT scanner with 4 x 1 mm detector collimation, 120 kV, 0.5 sec gantry rotation and 120 mAs scan parameters. Multiplanar reformatted images, virtual colonography and virtual colonoscopy images were compared with conventional colonoscopy. With conventional colonoscopy taken as the reference standard, the results were calculated with 95% confidence interval technique.
Results: Seventeen of the 23 polyps detected in conventional colonoscopy were identified correctly with multislice CT. Nine of 11 lesions with a diameter of 10 mm or greater (81%), three of four lesions with a diameter of 6-9 mm (75%), and five of eight lesions with a diameter of 1-5 mm (62%) were correctly identified with multislice CT.
Conclusion: Multislice CT colonography is a good alternative to other colorectal screening tests because it has high sensitivity for polyps 10 mm or larger in diameter, is relatively safe and minimally invasive.