Purpose or Case Report: Congenital prepubic sinus is a rare congenital anomaly of the urinary tract and is clinically active by discharge from a skin opening overlying the symphysis pubis. Its etiology is still unclear, and a variant of dorsal duplication of the urethra is the favored theory. It has been reported in males as well as in females. Its size and extent are variable, starting from prepubic area extending toward the bladder or urethra and may have a blind end.. This report is about the imaging approach in a series of 5 cases with similar clinical signs of presentation.

Methods & Materials: This report is about 5 cases (3girls , 2 boys) of the entity, with a presentation age range of 7 months to 9 years ( mean 45 months), with similar clinical signs of discharge. Use of imaging varied, including ultrasound , fistulography , VCUG and Pelvic MRI in 4, 2, 1 and 2 cases respectively.
Results: . Ultrasound with linear transducer could define the extent of the sinus with a cystic content. Direct fistulography was a challenge and via the thinnest catheter possible helped appreciate the depth of sinus and possible involvement of bladder or urethra. In our series there was no demonstration of implication of the bladder. VCUG was a conventional way of assessing status of the anterosuperior outline of the bladder as well as of urethra. MRImaging in one 9-year old was an elegant tridimensional depiction of anatomy of the sinus and bladder. One infant underwent an MR examination because of infection complication of a neighbouring urachal remnant with a concern for symphysis pubis osteomyelitis.

Conclusions: Available imaging modalities with their specific strengths and challenges help in defining timing for surgical intervention and anatomic pre-operative plan of congenital prepubic sinus.