Encysted hydrocele of the canal of Nuck in a 7-year-old female: A case report.

A 7-year-old girl presented complaining of right groin swelling for 1 week and underwent routine examination at the emergency department. An ultrasonography reported a well-defined cystic lesion with no internal vascularity, connected to the inguinal canal, and located lateral to the epigastric vessels. Images were not conclusive, and surgical excision was performed 2 days later, with an uneventful postoperative recovery. Intraoperatively, the lesion was identified as an encysted hydrocele of the canal of Nuck. During female development, the parietal peritoneum descended along the round ligament of the uterus through the inguinal ring and into the inguinal canal, which is known as "canal of Nuck." The round ligament is attached to the uterine cornu adjacent to the origin of the fallopian tube and to the ipsilateral labia majora. If the processus vaginalis does not close and remain patent, this could lead to fluid to pass through and accumulate to form a communicating hydrocele, and the opening is large enough to allow abdominal organs to herniate. This will lead to another differential diagnosis of inguinal swelling, inguinal hernia . This case highlights the importance of considering this rare entity in the differential diagnosis of groin swellings in pediatric females and the role of imaging in guiding management.