The computed tomography of colorectal tumors with water as the contrast medium

The diagnosis of colorectal carcinoma is based on double-contrast barium enema and endoscopy. However, in contrast to computed tomography (CT), these modalities do not permit a precise preoperative prediction wether a tumour is limited to the bowel wall or has spread into surrounding tissue. To improve the detection of colorectal neoplasms by CT we prospectively studied the use of intrarectally administered water for CT scan in 16 patients with colorectal cancer proved by barium enema and endoscopy. The water repletion technique allowed an improved depiction of the large bowel wall, and the primary tumour was demonstrated by CT in all cases. Furthermore the use of water prevented artifacts which was helpful in the evaluation of the liver for suspected metastases.