Table 1. The role of the radiologist.

General	Ischaemic priapism	In non-ischaemic priapism
Characterise cavernosal artery flow dynamics using ultrasound Identify cavernosal infarction and fibrosis with MRI Determine underlying cause of priapism if not clinically apparent—CT to identify occult malignancy; MRI to detect penile metastases Treatment of high-flow priapism with compression or embolisation Follow-up following treatment with ultrasound	Doppler ultrasound useful to: allow identification of cavernosal artery flow (no flow suggests probable cavernosal infarction) early treatment with penile implant may be appropriate identify variants of ischaemic priapism that still maintain high flow (often >1–2 m s–1) with high resistance (i.e. non-perfusing); early operation not advised owing to potential haemorrhagic difficulties MRI useful to: detect perfusion of corporal tissue; no perfusion suggests early prosthesis insertion detect rare causes of priapism, such as penile metastases	Doppler ultrasound useful to: detect high-flow, low-resistance waveform localise arteriocavernosal fistula treat fistula with compressionInterventional radiology allows: angiography and embolisation of fistula