Extratesticular lesions: a radiological and pathological correlation.

It is often difficult to make an exact pathological diagnosis of extratesticular lesions detected on ultrasound. This study aimed to clarify the sonographic criteria required for a more accurate diagnosis by performing a correlative study of the ultrasonographic findings and pathologic diagnosis. Of the 268 scrotal ultrasound examinations with extratesticular lesions reviewed, 81 had the diagnosis confirmed on pathological or clinical grounds. The major pathological entities reviewed in the study were epididymitis, hydrocele, cystic lesions of the epididymis, post-vasectomy lesions and solid extratesticular lesions. The sonographic appearances in both acute and chronic epididymitis were reviewed. Clinical epididymitis had a typical clinical presentation and distribution confined to the epididymal tail and ductus deferens. This should allow a specific diagnosis to be made. Cystic lesions of the epididymis included true epididymal cysts and spermatoceles, but these entities were not distinguishable from each other sonographically. Late complications of vasectomy have been recognized clinically as the 'Late Post-Vasectomy Syndrome', and the pathological changes have also been described. In this study the corresponding sonographic appearances of sperm granulomata, dilated efferent ducts and spermatoceles are documented. Most solid extratesticular lesions are areas of fibrosis termed 'fibrous pseudotumours', but adenomatoid tumours and papillary cystadenomata are the most common neoplastic lesions. By obtaining pathological correlations for many sonographic extratesticular abnormalities, we have clarified a number of issues and made several new observations.