Pediatric Cowper Duct Syringocele

Etiology: Cystic dilation of main duct of bulbourethral glands
— Simple: An open syringocele with a minimally dilated duct
— Perforate: An open syringocele with a bulbous duct draining into urethra though wide opening which can appear to be a diverticulum
— Imperforate: A closed syringocele with a bulbous duct that does not drain into urethra which resembles submucosal cyst appearing as mass in urethra
— Ruptured: An open syringocele with a thin membrane remaining in urethra after dilated duct rupture
Imaging VCUG: Radiolucent mass in urethra
Imaging US: Unilocular cystic lesion at posterior or posterolateral aspect of posterior urethra
Imaging MRI: Midline oval structure at base of penis near ventral aspect of proximal bulbous urethra
— T1WI: Low signal intensity
— T2WI: High signal intensity
DDX:
Complications:
Treatment: Surgical incision of the obstructed duct
Clinical: Presents with postvoid dribbling, urinary frequency, weak stream

Radiology Cases of Cowper Duct Syringocele

Radiology Cases of Cowper Duct Imperforate Syringocele

VCUG of Cowper duct imperforate syringocele — Lateral image of the urethra from the voiding phase of a VCUG exam shows a filling defect (arrow) in the posterior urethra.

Radiology Cases of Cowper Duct Perforate Syringocele

VCUG of Cowper duct perforate syringocele — Lateral images from a voiding cystourethrogram exam during voiding (above) show a long tubular tract filled with contrast inferior to the contrast filled urethra. Lateral image after voiding (below) shows retained contrast pooling in the tubular tract.

Radiology Cases of Cowper Duct Perforate Syringocele With Stricture of Membranous Urethra

Retrograde urethrogram of Cowper duct syringocele and stricture of the membranous urethra — Lateral image from a retrograde urethrogram exam shows a short tubular tract filled with contrast inferior to the contrast filled urethra. There is also a persistent long narrowing in the membranous urethra.