MR Imaging of the Penis and Urethra.

MR imaging has been increasingly used as a problem-solving adjunct after an initial ultrasound examination for a variety of penile disorders, and is the best cross-sectional imaging modality for the assessment of urethra and periurethral disease. Critical advantages of MR imaging for penile and urethra imaging include high soft tissue contrast resolution providing detailed anatomic evaluation, which is important for the demonstration and assessment of critical structures such as tunica albuginea or walls of the urethra, larger field of view for better evaluation of extent of disease, and demonstration of proteinaceous material and varying ages of the blood products.