Scrotal scanning: present value and limits of interpretation.

Forty-three testicular scans have been performed on 38 patients presenting with various scrotal symptoms. Scan diagnosis correlated correctly with the clinical findings in 86 per cent of cases. The most common cause of false positive testicular scan was found to be hydrocele. The mechanism responsible for this observation has been explored in a rat model. A false negative diagnosis was made in 2 cases owing to a small retracted scrotum in 1 patient and a markedly late discovered torsion in the second.