Hydrocele of the canal of Nuck in a girl: ultrasound and MR appearance

Abstract

Hydrocele of the canal of Nuck is a rare condition in females. A small evagination of parietal peritoneum forms the canal of Nuck. Failure of complete obliteration of the canal results in either an indirect inguinal hernia or a hydrocele of the canal of Nuck. We present a case in a 7-year-old girl. On ultrasound, there was a comma-shaped cyst with the tail directed cranially toward the inguinal canal. The cyst had no internal echoes and demonstrated increased through transmission. Coronal and axial MR showed a thin walled cystic mass.

Palpable inguinal mass in a girl after omphalocele repair: US findings

“…It is the female equivalent of the processus vaginalis testis in males which extends along the testes in the descent from the lumbar region to the scrotum. Normally, it undergoes complete obliteration during the first year of life [1]. Incomplete obliteration creates a potential passageway for indirect inguinal hernia.…”

“…Some authors [1,2] have described a comma-shaped tail extending from the lesion into the inguinal canal, while others describe the appearance as ''a cyst within the cyst'' [3] or a cystic mass with thin multiple septa [4,5]. The graded compression technique allows observation of a fluid-filled canal which connects the cyst with the abdominal cavity [2].…”

“…The graded compression technique allows observation of a fluid-filled canal which connects the cyst with the abdominal cavity [2]. Differential diagnosis of inguinal masses in female patients includes inguinal hernia (in which the fallopian tubes, ovaries, uterus and even ovarian cysts may slip into the hernial sac), lymphadenopathy, Bartholin's cyst and soft tissue tumor (lipoma, leiomyoma) and endometriosis of the round ligament [1,6,7]. Other pathologies are rare, such as vascular abnormalities (arterial and venous aneurysms), ganglion cyst of the femoralcoxal joint or paraspinal abscess extending into the inguinal region [3].…”

“…The most frequent causes of palpable inguinal masses in female patients include inguinal hernia, lymphadenopathy, Bartholin's cyst, soft tissue tumor (lipoma, leiomyoma) and endometriosis of the round ligament [1][2][3][4][5][6][7]. In contrast, hydrocele of the canal of Nuck is rarely the cause of palpable inguinal masses in female patients.…”

Cysts of the canal of Nuck: ultrasound and magnetic resonance imaging findings

“…Anderson et al [1] found a tubular anechoic mass extending along the course of the round ligament without any internal structures, thus representing a unilocular hydrocele. Park et al [5] described a cystic structure with a comma shaped tail directed towards the inguinal canal. The reported case was a cystic, thin-walled structure in the inguinal area with hypointense T1 signal and hyperintense T2 signal characteristics; it was the first report of MRI findings in this pathology in English literature.…”