The indications for scrotal ultrasound.

Scrotal ultrasound scanning is now a routine and mandatory investigation of the patient presenting with scrotal symptoms. The need for scrotal ultrasound scanning when the physical examination reveals no significant abnormality has not been previously assessed. We conducted a retrospective study of 160 patients attending for scrotal ultrasound over a period of 1 year. The accuracy of clinical examination was compared with the gold standard of ultrasound for identifying clinically significant lesions. The sensitivity, specificity and positive and negative predictive values were calculated. Four clinically relevant groups were used for analysis purposes: Group I, acutely painful scrotum with or without swelling; Group II, chronic testicular pain without swelling; Group III, chronic scrotal swelling with or without pain; and Group IV, the asymptomatic testis. In Group I, sensitivity was 100%, specificity was 81.3%, the positive predictive value was 92.1% and the negative predictive value was 100%. In Group II, sensitivity was 71.4%, specificity was 90.9%, the positive predictive value was 76.9% and the negative predictive value was 88.2%. In Group III, sensitivity was 88.9%, specificity was 66.7%, the positive predictive value was 92.3% and the negative predictive value was 57.1%. In Group IV, sensitivity was 33.3%, specificity was 100%, the positive predictive value was 100% and the negative predictive value was 93.9%. All clinically significant abnormalities were identified on clinical examination. Clinically insignificant lesions identified by ultrasound alone did not affect the clinical management. It is recommended that scrotal ultrasound is used in the acutely painful scrotum where a confident diagnosis cannot be made or there is failure to respond to treatment, and in the chronic swelling where a confident clinical diagnosis cannot be made.