Large Hydrocele. An US image through the long axis of the testis (T) demonstrates its homogeneous midlevel echogenicity. The head of the epididymis is seen as a small nodular structure (curved arrow) at the superior aspect of the testis. The tunica albuginea (straight arrow) is the tough fibrous capsule that covers the testis. The hydrocele (H) surrounds all portions of the testis except its posterior portion, where the testis is attached to the scrotal wall.

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