Introduction The development of the male genitourinary system is complex. Numerous anomalies of the male urethra exist, either as isolated anomalies or in combination with other disorders. The current understanding of the embryology and anatomy of normal male urethral development might help explain the causes of the various anomalies as well as their relationships. Embryology of the male urethra 1 1 2 Fig. 1 2  Fig. 2 4  3 4 4 2 4 Fig. 3 2  Fig. 4 4  Normal anatomy of the male urethra 5 6 Fig. 5 Normal male urethral anatomy  Fig. 6 P  short arrow  long arrow  The membranous urethra is the shortest, least distensible portion of the urethra. It is surrounded by the sphincter urethrae membranaceae (external sphincter), which in addition to vessels, nerves and deep transverse perineal muscle represents the urogenital diaphragm. The internal sphincter is located at the bladder neck. 5 Congenital anomalies of the urethra Posterior urethral valves 6 1 8 7 1 7 1 1 7 7 9 10 11 12 13 12 14 12 14 14 7 15 16 14 Fig. 7 arrow  8 Fig. 8 long arrow small arrow  Prune-belly syndrome 17 9 18 Fig. 9 a long arrow short arrow b  17 Congenital urethral stricture 19 1 20 7 19 10 20 Fig. 10 Congenital urethral stricture. A markedly dilated urethra is seen proximal to a congenital stricture in the bulbous urethra. Retrograde urethrography in this patient (not shown) demonstrated a focal narrowing at the bulbous urethra with a normal penile urethra. The site of obstruction is more distal than that seen with PUV  Congenital urethral polyps 11 21 22 Fig. 11 a arrow b arrow  Mullerian duct remnants: enlarged prostatic utricle and Mullerian duct cyst 23 24 23 12 Fig. 12 arrow  Midline cystic structures arising at the dorsal aspect of the prostatic urethra represent two distinct categories of Mullerian duct remnants. They are described as enlarged prostatic utricles when they communicate with the urethra and as Mullerian duct cysts when they do not. These terms have been used interchangeably, contributing to confusion in nomenclature. 23 25 23 26 13 23 Fig. 13 arrow asterisk  23 25 23 24 23 26 14 25 Fig. 14 arrow asterisk  Cowper’s syringocele 27 28 15 29 Fig. 15 arrow  30 30 31 Clinically, patients present with frequency, urgency, dysuria, post-void incontinence, hematuria or urinary tract infection. Diagnosis is made by VCUG, retrograde urethrography or urethrocystoscopy. Treatment requires marsupialization of the syringocele. Anterior urethral valves and diverticula 32 33 32 32 33 28 16 31 32 34 35 32 Fig. 16  Arrow  36 17 37 Fig. 17 arrow  Megalourethra 38 39 18 Fig. 18 arrow  Urethral duplication 40 40 41 42 43 44 40 41 43 19 20 44 41 Fig. 19 arrows  Fig. 20 arrows  Congenital urethroperineal fistula 41 45 45 39 Anorectal malformations 46 47 48 49 50 39 40 40 47 51 21 22 Fig. 21 arrow  Fig. 22 Anorectal malformation. Distal loop study in an infant with a high imperforate anus demonstrates a fistula extending from the rectum to the posterior urethra  Conclusion The development of the male urethra is complex. Although understanding its embryology can help explain certain anomalies, there are others in which the embryologic defect has not been elucidated. Imaging, including VCUG and retrograde urethrography, is helpful in defining the anatomy and identifying associated findings.