[Computed tomography features after cystectomy]

Continent urinary diversions are most often performed in the patients who underwent cystectomy for malignancy, typically an invasive bladder carcinoma. There is no ideal surgical technique suitable to every case to reconstruct the lower urinary tract because many factors affect patients selection--e.g., tumor stage, patient's age and overall condition, and so on. Since radiologists play an important role in following up these patients, they must be familiar with postoperative anatomy to detect complications promptly. From 1985 to 1991, forty-two patients underwent radical cystectomy and urinary diversion; four different kinds of diversion were performed: ureterocutaneostomy, ureteroileocutaneostomy, ureterosigmoidostomy and total bladder replacement with ileal or ileocecal segments. The patients were examined with CT six months after surgery and then every year. The usual postoperative CT findings are reported. In the patients who underwent radical cystectomy, a loop of sigmoid colon fills the space left empty by surgery; less frequently, a loop of ileum or of both ileum and sigmoid colon occupies the bladder fossa. The CT findings in the four different kinds of diversion were different enough to be easily distinguished: ureters joined to skin, to an ileal loop or to sigmoid colon are found in ureterocutaneostomy, ureteroileocutaneostomy and ureterosigmoidostomy, respectively. Also the two examined kinds of neobladder (Lebag and "Padovana" techniques) exhibited different volumes and shapes. The anastomosis between ureters and intestinal segment could not be identified in all cases. Nonetheless, CT is the imaging method of choice after cystectomy, as it allows the thorough evaluation of the genitourinary apparatus.