3-DIMENSIONAL COMPUTERIZED-TOMOGRAPHY AND VIRTUAL-REALITY ENDOSCOPY OF THE RECONSTRUCTED LOWER URINARY-TRACT

Purpose: We describe postoperative surgical anatomy after orthotopic r econstruction of the lower urinary tract using 3-dimensional (D) compu terized tomography (CT) and virtual reality endoscopy. Materials and M ethods: Electronic beam CT was performed in 39 men and 15 women a mean of 60 years old with an orthotopic ileal neobladder (50) or ureteroil eal rectosigmoidostomy (4), followed by 3-D reconstruction of the pelv ic anatomical structures using specialized computer hardware and softs ware. The mean interval between surgery and CT was 15 months (range 3 to 110) and the mean interval between 2 subsequent 3-D CT studies in 2 2 patients was 6 months (range 3 to 9). Results: CT time with the pati ent on the table was 45 minutes and computerized 3-D reconstruction ti me with the patient off the table was 4 to 5 hours. The pouch had a sm ooth ovoid shape in 66 and 82% of the patients on the first and second 3-D CT studies, respectively. Mean length of the antireflux nipple wa s 4 cm. (range 2.5 to 8) and mean length of the afferent limb was 6 cm . (range 3 to 15). There were no radiologically significant sex specif ic differences in the shape or dimensions of the urinary reservoirs, e xcept for a tendency toward more acute angles between the pouch and re mnant urethra. No pathological findings were visible on 3-D CT that we re not also evident on conventional CT. Conclusions: Three-D CT may be clinically useful for surgical planning of a lower abdominal reoperat ion or unexplained findings and symptoms in patients with bladder subs titutions. Cost and time expenditures for processing preclude its rout ine use in all cases. Virtual reality endoscopy may be a valuable tool for teaching and scientific purposes.