Conventional Colonoscopy is the best screening technique available.  It has the additional value of providing the possibility of removing small polyps during the procedure.

However this technique presents pitfalls as:  

Computed Tomography (CT) Colonography is an emerging technique devised to replace Colonoscopy.  It uses computed tomography scanner. 

CT is a radiography technique in which a 3-D image of a body structure, in this case the colon, is constructed by computer from a series of images.  It allows for a detailed image of the section required while blurring out images on other planes.

It is an non invasive procedure and is designed to be less stressful and intrusive on the patient.

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