Introduction: Colovesical fistulae are the most common type of fistulous communication between the urinary bladder & 
the bowel. The relative frequency of colovesical fistulae is difficult to ascertain because multiple disease processes could be complicated by such fistulae. The main purpose of this study is to investigate the role of 3-dimensional tomographic 
computed reconstruction in diagnosis of colovesical fistulae. 
Materials & methods: We compared 3-dimensional CT images of colovesical fistulae to conventional CT images in 4 
patients. the records of these 4 patients were also reviewed retrospectively with regards to clinical picture , diagnostic studies & surgical repair. 
Results: The etiology of colovesical fistulae was sigmoid diverticulitis in 3 cases & bladder carcinoma in the fourth case. 
Successful surgical repair was facilitated by pre-operative 3-dimensional CT images. 
Conclusions: CT scan should be included as part of the initial evaluation of patients with suspected colovesical fistulae. 
Three-dimensional CT reconstruction provides superior spatial details & can clarify complex anatomical relationships preoperatively which increases the surgeon's comfort during surgical repair of these cases.