Colorectal polyps: Detection with multi-slice CT colonography

Abstract

Summary. Purpose: To compare the performance of virtual and conventional colonoscopy for the detection of colorectal polyps using a multislice spiral CT scanner (MSCT). Materials and Methods: 48 patients (20 women, 28 men, mean age 61.5 years) with clinical indication for conventional colonoscopy were prospectively studied using a MSCT (Somatom Volume Zoom, Siemens, Forchheim). Examination was performed after standard oral preparation for colonoscopy and colonic distension with room air and i. v. butylscopolamin. Images were obtained in prone and supine position using a detector configuration of 4 1 mm, a table feed of 5 mm/rotation at 140 mAs and 120 kV. Slice thickness and reconstruction increment were 3 and 1.5 mm, respectively. CT data were assessed by two blinded radiologists on a Vitrea workstation (Vital Images, USA) using a software with multiplanar and volume-rendering capabilities. Results: 33 patients had normal findings on conventional colonoscopy. In 15 patients a total of 30 polyps and one carcinoma with stenosis were identified. MSCT-colonography identified the carcinoma and 23 polyps (77 %). 3 of 3 polyps were 10 mm or more (100 %), 6 of 7 were 5.1 to 9.9 mm (86 %) and 14 of 20 were 5 mm or smaller (70 %). There were 13 false positive findings for polyps (10 lesions < 6 mm in 5 patients) and no false positive finding of carcinoma. Conclusions: MSCT colonography allows accurate detection of polyps larger than 10 mm. Compared to published results of single-slice CT, multislice CT colonography increases the rate of detection of small colorectal polyps in particular. However, false positive results still remain a problem. Schlüsselwörter: Polypen ± Computertopographie ± Kolographie ± Mehrschicht-CT

Diagnostic performance of computed tomography colonography and colonoscopy: a prospective and validated analysis of 231 paired examinations

“…In a later meta-analysis, Halligan et al reported a higher per-patient sensitivity of 86% (range 79-100%) for medium and large polyps, and 93% (64-100%) for large polyps (8). However, only seven of 24 studies met the required methodological quality in this analysis (14,19,21,27,31,33), including one multicenter study (19). Since then, some studies have reported higher sensitivities (10,30), while others (including another multicenter study) have reported lower sensitivities (5,25) than those calculated by SOSNA et al and HALLIGAN et al (8,26).…”

Prospective Study Comparing Multislice CT Colonography With Colonoscopy in the Detection of Colorectal Cancer and Polyps

“…These remain the best results published using spiral CTC and are matched by the results in this study. Wessling et al 21 in a smaller study of 40 patients using MCTC reported a detection sensitivity of 100 percent for polyps Ն10 mm (3 of 3) and 86 percent for polyps sized 5.1 to 9.9 mm (6 of 7). Interestingly, this group reported a sensitivity of 77 percent (14 of 20) for polyps Յ5 mm that has not been observed in this or other studies.…”

Multislice CT Coronary Angiography: Evaluation of an Automatic Vessel Detection Tool

“…The analyzed workstation has already proven to be effective for automatic and rapid estimation of the volume of abdominal aortic aneurysms [15], for detection of colorectal polyps with MSCT [16], and for 3D volume rendering for accurate measurements for dental implant placement [17]. Our results show that automatic vessel detection for display of the coronary vessels on curved MPRs and on planes orthogonal to the vessel is feasible with the workstation, while reducing the time required to create reformations by a factor of approximately two.…”