The aim of this study was to assess the diagnostic value of erotically enhanced penile colour Doppler sonography as a minimally invasive tool to evaluate penile haemodynamics. Colour Doppler sonography was used to study the cavernosal arteries of 135 consecutive impotent patients after intracavernous injection of a vasoactive mixture (injection phase) and after subsequent genital and audiovisual sexual stimulation (stimulation phase). The erectile response was upgraded after the adjunct of genital and audiovisual stimulation in 36% of patients. Colour Doppler assessment performed after the stimulation phase identified 16% of patients as arteriogenic despite normal erections, and 7% of patients falsely diagnosed as venogenic after the injection phase. When colour Doppler sonography and the injection-stimulation test are performed together as a single diagnostic procedure the overall diagnostic accuracy is significantly enhanced.