Hydrocele of the canal of Nuck: a case report with magnetic resonance hydrography findings

Abstract

Hydrocele of the canal of Nuck, also called the "female hydrocele," is a rare developmental disorder in females. This entity is now believed to be more common now in comparison with previous reports; however, it is still an unfamiliar problem for physicians. The processus vaginalis accompanies the round ligament through the inguinal canal into the labium majus. This evagination of the parietal peritoneum forms the canal of Nuck in the female. The canal of Nuck normally loses its connection with the peritoneal cavity during the first year of life, but can result in a hernia or hydrocele when the connection of the canal of Nuck fails to close. Here, we present the case of a 43-year-old female who complained of swelling in the right inguinal region. Coronal and axial magnetic resonance imaging (MRI) revealed a cystic mass lesion with an irregular shape in the right inguinal region, and smaller cystic lesions extending alongside the right round ligament were also identified in the right side of the pelvic cavity. Magnetic resonance (MR) hydrography revealed the uninterrupted cystic lesion from the inguinal region to the pelvic cavity, with constrictions at the internal and external inguinal rings. These MR findings proved to be incredibly useful for surgical planning.

Keywords: Hydrocele of the canal of Nuck; MR hydrography; MRI; Round ligament.

Fig. 1

Axial T2-weighted MRI. Axial T2-weighted MRI shows a cystic mass (black arrows) measuring 48 × 37 mm in the right inguinal region. A smaller cystic lesion and fluid collection extend along the right round ligament in the pelvic cavity. Round ligament (white arrowheads), inferior epigastric artery and vein (white arrows), bilateral ovary (black arrowheads), and myomas (asterisks)

Fig. 2

Coronal T2-weighted MRI and MR hydrography MIP images. Coronal T2-weighted MRI (a) and MIP images of MR hydrography [frontal view (b) and right anterior oblique view (c)] show an uninterrupted large cystic lesion extending from the pelvic cavity to the right inguinal region, measuring 13.5 cm in diameter with constrictions at the internal inguinal ring (arrow) and external inguinal ring (arrowhead)

Fig. 3

Intraoperative photograph. Surgery revealed a cystic lesion with a smooth (arrow), reddish surface, and minimal internal hemorrhage (a). High ligation at the internal inguinal ring and resection of the outside of the cystic lesion was performed. The lesion had adhered to the right round ligament of the uterus (b)