Cross sectional imaging features of cryptorchidism
Cryptorchidism occurs when there is incomplete descent of one or both testicles into the scrotum and is seen in 3% of neonates and in 1% of infants (since many testicles descend by age one) and adults. The ectopic testicle is most commonly found in or below the inguinal canal but may less commonly be found elsewhere in the abdomen or pelvis.
MRI is superior to US for localization of a cryptorchid testicle, especially when located in the abdomen. On US, the cryptorchid testicle is usually small and hypoechoic relative to the normal testicle and has an echogenic mediastinum. On MRI, the cryptorchid testicle is usually small relative to the normal testicle and has increased T2-weighted signal intensity relative to skeletal muscle, similar to the normal testicle.
