Ultrasonography and the impalpable testis.

The accuracy of inguinal ultrasonography in the pre-operative localization of the maldescended testis was assessed in 51 patients with 57 maldescended testes. Pre-operative sonographic results were compared with the clinical assessment and the operative findings. Testes located in the inguinal canal or at the internal ring, which were occasionally impalpable, were readily demonstrated by sonography. The management of children with an impalpable maldescended testis should include a sonographic examination as the investigative procedure of choice.