Critical validation of ultrasound Doppler in the diagnosis of torsion of undescended testis.

BACKGROUND Testicular torsion associated with undescended testis is uncommon but requires immediate treatment. Ultrasound Doppler is recognized as the preferred imaging modality for testicular torsion due to its high specificity, sensitivity and availability. OBJECTIVES To determine the accuracy of ultrasound Doppler in diagnosis of torsion of undescended testis. METHODS We describe three patients with known undescended testis who were admitted with groin pain and had preoperative ultrasound Doppler. The discrepancy between these and the intraoperative findings is discussed. RESULTS In two patients incarcerated inguinal hernia was diagnosed with ultrasound Doppler; however, surgery revealed torsion of an undescended testis. In the third patient ultrasound Doppler diagnosed torsion of undescended testis, but at surgery incarcerated inguinal hernia was found, without evidence of testicular torsion. CONCLUSIONS Torsion of undescended testis should be a clinical rather than radiologic diagnosis.