A hydrocele is a collection of fluid between the visceral and parietal layers of the tunica vaginalis. Hydroceles can be congenital, idiopathic, or acquired. Acquired hydroceles are the results of infarction, inflammation, neoplasm, or trauma.
Sonographically hydroceles may appears as anechoic fluid in the scrotal sac surrounding the testicle and epididymis. Occasionally, small particles and septations are seen within the fluid.

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