Citation, DOI and article data
Usually a painless, incidental finding but can present as a mass lesion if large 3.
Spermatoceles are usually unilocular but can be multilocular and may be associated with a prior vasectomy. They are more common than epididymal cysts, but can appear very similar.
The exact cause of spermatoceles remain unclear but is thought to be due to blockage of the epididymal ducts with proximal dilatation. This may be idiopathic or secondary to an infectious or inflammatory process 3.
At sonographic examination, spermatoceles are well-defined epididymal hypoechoic lesions usually measuring 1-2 cm and demonstrating posterior acoustic enhancement. They are usually irregular, with fine low-level internal echoes and sometimes septations.
General imaging differential considerations include:
- unlike epididymal cysts, spermatoceles often contain low-level echogenic proteinaceous fluid and spermatozoa
- spermatoceles can be septate
- they can however be anechoic and thus indistinguishable from epididymal cysts
- ectasia of rete testes: intratesticular spermatocele communicates with the seminiferous tubules, however ectatic rete testes do not communicate directly
- intratesticular simple cyst: simple cysts are usually smooth-walled and anechoic, while spermatoceles show irregular wall with low-level echoes
- 1. Dogra VS, Gottlieb RH, Oka M et-al. Sonography of the scrotum. Radiology. 2003;227 (1): 18-36. doi:10.1148/radiol.2271001744 - Pubmed citation
- 2. Dogra VS, Gottlieb RH, Rubens DJ et-al. Benign intratesticular cystic lesions: US features. Radiographics. 2001;21 Spec No : S273-81. Radiographics (link) - Pubmed citation
- 3. Graham. Glenn's Urologic Surgery. ISBN:0781791413. Read it at Google Books - Find it at Amazon