Virtual colonoscopy in ulcerative colitis: a comparative study

ABSTRACT

Ulcerative colitis [UC] is an inflammatory disease of the colon and rectum. Many investigations are put for diagnosis and follow up of its course and complications. Virtual reality imaging is a new technology that combines helical computed tomography, magnetic resonance [MR] data and advanced three-dimensional graphics software to generate endoluminal perspective images of hollow organs.Computed tomography colonography [Virtual colonoscopy] is an imaging procedure in which a series of helical CT scans of the patient's colon are rendered by computer into slices that can be visualized as serially combined images to provide a three-dimensional tour of the colon. In this work, we try to evaluate the sensitivity and accuracy of virtual colonoscopy as a new modality for colorectal evaluation in patients who had been subjected to traditional colonoscopy and double-contrast barium enema study and who were diagnosed as having a chronic intermittent ulcerative colitis disease and to correlate the findings of virtual colonoscopy with those of conventional colonoscopy and barium study. This work was conducted on eighteen [18] patients admitted to Banha Gastroenterology unit. They were ten [10] males and eight [8] females with age ranging form 19-41 years; mean age [28.1 +/- 11.5] years. All patients were subjected to complete medical history, thorough clinical examination, routine laboratory tests and special laboratory investigations as carcinoembryonic antigen [CEA] and occult blood in stool. Abdominal ultrasonography, barium double-contrast enema, traditional colonoscopy and virtual colonoscopy were clone for all patients. Colonoscopic biopsies were obtained as a routine in every case. In our study, traditional colonoscopy gave positive data in 100.0%, while virtual colonoscopy gave positive results in 61.1% and barium enema gave positivity in 55.6%. Characteristic features of ulcerative colitis were evident on the 2-D images and the 3-D endoluminal and extraluminal images obtained by virtual colonoscope. From this study, we concluded that CT colonography [Virtual Colonoscopy] is a non invasive procedure feasible lor follow up of ulcerative colitis and could be used to monitor the extent of intestinal inflammations as well as possible complications such as malignant changes, strictures or stenosis in most patients. Further technical advances will improve the performance of CT colonoscopy and will allow patients available imaging modality for full structural changes of the colon