Anterior urethral valve in the fossa navicularis presenting as a split urinary stream in a child.

An anterior urethral valve is uncommon compared to a posterior urethral valve as a cause of lower obstructive uropathy. Furthermore, an anterior urethral valve in the fossa navicularis is extremely rare. We describe the case in a 6-year-old boy who presented with a split urinary stream. Endoscopy revealed an anterior urethral valve in the fossa navicularis, and we successfully incised the valve with a hook knife. We should consider the possibility of an anterior urethral valve in any child with an abnormal urinary stream.