[A case report of Cowper's syringocele in an adult treated with transurethral unroofing].

We present an adult case of Cowper's syringocele. A 19-year-old male presented with the chief complaint of persistent post-voiding dribbling 5 months after onset. Urethroscopy demonstrated a thin membrane with a small orifice on the ventral aspect distal to the external sphincter. Magnetic resonance imaging showed a restiform shadow on the left side of the corpus spongiosum. Retrograde urethrogram showed filling of diverticulum-like structure in the region of urethral bulb terminating in the urogenital diaphragm. Considering the results mentioned above, we diagnosed the patient with Cowper's syringocele. Transurethral unroofing of the Cowper's syringocele was performed with a cold knife, and the excessive tissue on the edge of syringocele was electroresected to avoid recurrence. His post-voiding dribbling resolved completely after the procedure and has not recurred in 13 months postoperatively. Cowper's syringocele is typically diagnosed presenting with hematuria, urinary tract infection, and disuria in male infants and children. Adult cases of Cowper's syringocele are rare, and only 32 cases including the present case have been reported. Proper awareness of this entity and careful evaluation are important if patients present with persistent adult-onset voiding dysfunction.