Objective To compare computed tomography (CT) angiography (CTA) obtained by multi-slice CT (a new minimally invasive method) with the current standard of arterial imaging, digital subtraction angiography (DSA), in diagnosing arteriogenic erectile dysfunction (ED). Patients and methods Twenty-one patients with suspected arteriogenic ED underwent DSA and CTA after providing informed consent. Prostaglandin E1 was injected into the penile cavernosal body and then non-ionic contrast medium was rapidly infused into the antecubital vein. The DSA and CTA images were diagnosed as showing a normal or abnormal status by three reviewers independently. CTA was undertaken on an outpatient basis but DSA required hospitalization. Results In the 42 internal pudendal arteries, DSA showed 28 normal and 14 impaired arteries; CTA showed 21 normal arteries and 21 occlusions. The CTA image correlated closely with the diagnosis of stenosis or occlusion in internal pudendal arteries, with a sensitivity of 93%, a speci®city of 71% and an accuracy of 79%. In the cavernosal arteries, DSA depicted 14 normal and 28 impaired arteries; CTA showed seven normal arteries and 35 occlusions. The CTA image agreed closely with the diagnosis of stenosis or occlusion in cavernosal arteries, with a sensitivity of 96%, a speci®city of 43% and an accuracy of 79%. Of the 42 inferior epigastric arteries, DSA could not depict 11 arteries but CTA showed all 42 inferior epigastric arteries. Conclusions CTA images correlated with DSA images; at present DSA is better than CTA in visualizing stenosis in ®ne arteries. However, CTA is less invasive and relatively inexpensive, and in future will probably provide even greater improvements in graphic quality. CTA would be an adequate replacement for DSA in evaluating internal pudendal arterial stenosis.

Objective To assess the effect of radical retropubic prostatectomy on erectile function, by evaluating objectively patients' erectile function before and after surgery. Patients and methods The study comprised 126 patients with clinically localized prostate cancer who were scheduled to undergo radical retropubic prostatectomy. After giving informed consent for the study, 123 patients underwent intracavernosal injection tests, colour Doppler ultrasonography and nocturnal penile tumescence monitoring before and after surgery. Results From the intracavernosal injection tests and nocturnal penile tumescence monitoring, 21 patients (17%) were evaluated as having normal erectile function before surgery. After radical retropubic prostatectomy, nine (43%) of these 21 potent men had preserved erectile function. In eight patients whose neurovascular bundles were preserved, ®ve were potent after surgery. The cause of erectile function after surgery was a neurogenic disorder in seven and a related vascular disorder in ®ve. Conclusion From objective tests of erectile function on patients scheduled to undergo radical prostatectomy, 17% had normal erectile function. However, even after nerve-sparing radical retropubic prostatectomy, the proportion retaining potency was unsatisfactory. Although a neurological disorder was the main cause of erectile dysfunction after surgery, vascular disorders were also important.