Transverse testicular ectopia detected by MR imaging and MR venography

Crossed testicular ectopia is a rare anomaly, characterised by migration of one testis towards the opposite inguinal canal. In most reported cases, the correct diagnosis was not made pre-operatively. We report a case of transverse testicular ectopia diagnosed pre-operatively with MRI. MRI and MR venography demonstrated unilateral location of both testes in the right inguinal canal, which was confirmed by surgery. We provide a brief literature review of transverse testicular ectopia and the imaging of undescended testis.