To evaluate the role of computed tomographic virtual cystoscopy (CTVC) in the detection of bladder neoplasms and to compare CTVC at conventional and reduced milliAmperes-second (mAs) settings.Twenty-four patients with known bladder neoplasms from previous conventional cystoscopy were examined with CTVC. The urinary bladder was insufflated with room air and helical CT data were obtained. Virtual images were created using volume rendering algorithms. In eight patients we used both regular (240) and reduced (70) mAs values. The lesions were recorded on transverse tomographic slices and virtual images and compared with conventional cystoscopy, operative and pathology results.All bladder lesions (30) seen on conventional cystoscopy were demonstrated with CTVC. Two lesions detected on imaging studies and subsequently found at operation were not seen on conventional cystoscopy. In a third case of a neobladder, conventional cystoscopy was impossible due to neoplastic involvement of the penis. In all cases the lesions were equally conspicuous with conventional and low mAs values.Computed tomographic virtual cystoscopy is a minimally invasive technique that can provide comprehensive information about urinary bladder tumors. Furthermore, low mAs studies are equally effective for the examination of such patients.