title: [CT colonography as routine method].
abstract: OBJECTIVE
  Colorectal cancer is a major public health challenge in Austria and Germany. As the participation in dedicated colonoscopy screening programs is rather low, the question of alternative methods is raised again and computed tomography (CT) colonography seems to be a gentle alternative with a very high patient acceptance.
  
  
  METHODS
  In recent years CT colonography (CTC) has been established besides conventional colonoscopy as a radiological method for the investigation of the entire colon. From axial two-dimensional images three-dimensional images can be generated, allowing a virtual flight through the colon which is why this technique is also known as virtual colonoscopy.
  
  
  METHODS
  The technique of CTC has been improved continuously during recent years. On the one hand the steady decrease in the layer thickness (currently ≤ 1 mm) has improved the resolution of volume data sets and on the other hand there has been significant progress in postprocessing.
  
  
  METHODS
  Numerous studies have recently shown that the significance of CTC in the detection of advanced adenomas is similar to conventional colonoscopy.
  
  
  RESULTS
  Meanwhile CT colonography is now a routine investigation method established in both symptomatic and asymptomatic patients (screening).
  
  
  CONCLUSIONS
  Study data now clearly show that CTC, as an alternative to conventional colonoscopy, is a powerful method for investigation of colorectal cancer. To achieve good results adequate preparation including fecal tagging, standardized technical procedures during the investigation and expertise in both 2D and 3D reading are essential.
authors.affiliation: Institut für diagnostische und interventionelle Radiologie, Krankenhaus Elisabethinen Linz, Fadingerstr. 1, A-4010, Linz, Österreich.
authors.forename: G
authors.initials: G
authors.lastname: Böhm
authors.forename: T
authors.initials: T
authors.lastname: Mang
authors.forename: M
authors.initials: M
authors.lastname: Gschwendtner
mesh_terms: D001317:Austria; D023881:Colonography, Computed Tomographic / Q000379:methods* / Q000639:trends*; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D019317:Evidence-Based Medicine; D005858:Germany; D006801:Humans; D011856:Radiographic Image Enhancement / Q000379:methods*