Computed tomography colonography in routine clinical practice

The American Journal of Surgery, 2004

Background: Computed axial tomography (CT) colonography is the latest radiologic technique to be used to image the large bowel. We studied its role as a diagnostic tool in colorectal practice. Methods: One hundred and three patients suspected of having colorectal pathology underwent CT colonography. Results: CT colonography suggested a diagnosis of colonic carcinoma in 18 patients, and 17 of these underwent surgery. A colorectal neoplasm was not found in only 1 patient who had extrinsic colonic compression by an ovarian cyst. Twenty-one patients had suspected colonic polyps on scanning. Subsequent endoscopy in 19 of these patients confirmed the presence of polyps in only 10. CT colonography also revealed valuable extracolonic pathology: 8 occult noncolonic neoplasms and 163 other incidental findings. Conclusions: CT colonography has good patient compliance and is a useful diagnostic modality in detecting colorectal neoplasms. Its main advantage over other such investigative tools is its ability to detect extracolonic pathology.

Background: Conventional colonoscopy (CC) requires an experienced operator to avoid technical or interpretative errors, and an endoscopic error rate of 14% for tumor localization has been reported. We evaluated the impact of computed tomographic colonography (CTC) on surgical treatment strategy in patients with CC reported as having colorectal neoplasm. Methods: Fifty-three patients testing positive for colorectal neoplasm on CC underwent CTC: 32 patients had CC in our hospital (group A) and 21 had CC in area hospitals (group B). All CTC procedures were performed with a multidetector CT system. The results of CTC and CC were compared with that of surgery. The preoperative surgical planning evaluated on the basis of CC and CTC was compared with the actual surgical approach, and the percentage of patients in whom CTC modified the treatment strategy suggested by CC was calculated. Results: CTC changed the treatment strategy in four of 53 patients (7.5%) in whom CC showed technical or interpretative errors. Group analysis showed that CTC did not influence the surgical management in any patient in group A but did affect treatment strategy in four of 21 patients (19%) in group B. The effect of CTC on treatment strategy between groups was statistically significant (p<0.05). CTC identified five adenomas and three adenocarcinomas localized proximally to an impassable stenosis. Conclusion: CTC can be used to reevaluate the findings of a positive CC and can indicate a more correct ther-apeutic approach in patients with colorectal neoplasms who are candidates for surgery.

Radiology and Oncology, 2010

Disclosure: The authors have no conflicts of interest to disclose.

American Journal of Roentgenology, 1999

C T colonography is a new tool for detecting colorectal neoplasms that uses volumetric CT data. The CT data set is acquired after a patient has undergone bowel cleansing and an air enema and is performed with helical CT using a narrow collimation and reconstruction interval [ 1-4]. Volumetric data are then analyzed using a commercial or proprietary CT colonography workstation, which provides an interactive display of multiplanar two-dimensional (2D) and three-dimensional (3D) images of the colon for the interpreting physician. The performance of CT colonography has recently been assessed in patients with known or suspected polyps and has been shown to be competitive with other full structural screening tests [I]. Our purpose is to display common pseudolesions that can simulate true lesions, to display polyps and mass lesions that are easily overlooked, and to discuss problem-solving methods available with CT colonography that allow physicians to differentiate between pseudolesions and true polyps and masses.

International Journal of Colorectal Disease, 2011

Introduction When 'whole colonic imaging' is indicated, clinicians must decide between optical colonoscopy, barium enema and CT colonography (CTC). CTC is a relatively new technique which has become increasingly accessible in the UK over the past 5 years. As radiologists have gained experience and scanning parameters have standardised, there have been substantial improvements in both the accuracy and safety of CTC. Methods We review evidence from observational studies and randomised trials, and draw on expert opinion, to provide a comprehensive discussion of the current role of CTC in both symptomatic and asymptomatic individuals. Conclusions The emergence of CTC could soon entirely obviate the need for barium enema. CTC now has a complementary role alongside colonoscopy in symptomatic patients and a possible future role in colorectal cancer screening in the UK.

Gastroenterology, 2004

Gastrointestinal Endoscopy, 2012

Cancer Imaging, 2004

Colon cancer is the second leading cause of cancer-related death in the Western world. Approximately 80-90% of colon cancers develop in adenomas after mutations. The risk of encountering malignancy increases with the size of the adenomatous polyp. It is approximately 1% in adenomas <1 cm, and increases to 10% for adenomas 1-2 cm, and 20-53% for adenomas >2 cm. CT colonography (CTC) is a new technique, which allows, after bowel preparation and distension of the cleansed colon, to generate a volumetric display of the colon. Multi-detector CTC has a sensitivity of 93-100% and 70-83% for detection of polyps sized ≥10 mm and 6-9 mm, respectively. For detection of colorectal cancer, CTC has a sensitivity of 83-100%. CTC is especially of value in patients with incomplete colonoscopy due to stenosis or colon elongation. It reliably detects synchronous cancers proximal to occlusive colon cancers, when colonoscopy fails to evaluate the entire colon. First results of a colon cancer screening study have shown that CTC is equal or even slightly superior to conventional colonoscopy in detection of adenomatous polyps ≥8 mm. Moreover, CTC detects clinically significant extracolonic abnormalities not shown by colonoscopy. To increase the patient acceptance for widespread application of CTC cancer screening the issue of patient discomfort by bowel preparation and radiation exposure needs to be addressed further.

Gastroenterology, 2004

Since the initial introduction of CTC by Vining et al. in 1994 1 a number of studies have compared CTC with colonoscopy. Early reports typically involved small populations at high risk for colorectal pathology and used single-row scanners. In these studies, the perpolyp analyses showed that CTC was poor at detecting small lesions (sensitivity, 11%-55%) but slightly better for medium-sized (6 -9 mm) and large lesions (Ն10 mm) with sensitivities ranging from 34% to 82% and 50% to 91%, respectively. The per-patient sensitivity, although Abbreviations used in this paper: CT, computed tomography; CTC, computerized tomographic colonography.

Radiology, 2008

Purpose: Aim was to evaluate the accuracy of computed tomography colonography (CTC) for detection of colorectal neoplasia in a Fecal Occult Blood Test (FOBT) positive screening population. Methods: In three different institutions, consecutive FOBT positives underwent CTC after laxative free iodine tagging bowel preparation followed by colonoscopy with segmental unblinding. Each CTC was read by two experienced observers. For CTC and for colonoscopy the per-polyp sensitivity and per-patient sensitivity and specificity were calculated for detection of carcinomas, advanced adenomas, and adenomas. Results: In total 22 of 302 included FOBT positive participants had a carcinoma (7%) and 137 had an adenoma or carcinoma ‡10 mm (45%). CTC sensitivity for carcinoma was 95% with one rectal carcinoma as false negative finding. CTC sensitivity for advanced adenomas was 92% (95% CI: 88-96) vs. 96% (95% CI: 93-99) for colonoscopy (P = 0.26). For adenomas and carcinomas ‡10 mm the CTC per-polyp sensitivity was 93% (95% CI: 89-97) vs. 97% (95% CI: 94-99) for colonoscopy (P = 0.17). The per-patient sensitivity for the detection of adenomas and carcinomas ‡10 mm was 95% (95% CI: 91-99) for CTC vs. 99% (95% CI: 98-100) for colonoscopy (P = 0.07), while the per-patient specificity was 90% (95% CI: 86-95) and 96% (95% CI: 94-99), respectively (P < 0.001). Conclusion: CTC with limited bowel preparation performed in an FOBT positive screening population has high diagnostic accuracy for the detection of adenomas and carcinomas and a sensitivity similar to that of colonoscopy for relevant lesions.