Summary: An 18-year-old male came with complaints of double urinary stream since
birth. He had no difficulty or pain during micturation and had no
history of trauma or prior urethral instrumentation. On local
examination, the patient had an epispadiac urethra with double meati.
There was a minimal degree of chordee observed. Bilateral gonads were
normal and were situated within the scrotal sac.
A diagnosis of complete duplication of urethra type 2A-1 as per
Effmann’s classification (see discussion for classification) was made.
A plain radiograph of the abdomen and pelvis was done to look for any
bony abnormalities. Dynamic retrograde urethrography was requested as a
part of routine urological evaluation, which revealed complete
duplication of the penile and bulbous urethra (Figures 1 and 2). However
the posterior urethra could not be well evaluated. This was, hence,
followed by a voiding cystourethrography, which revealed a complete
duplication of the anterior as well as posterior urethra (Figure 3).
However, the bladder was normal. On an academic basis, a sonourethrogram
was performed using a linear 12-7 MHz high-resolution transducer. As
the ventral urethral meati was wider in caliber as compared to the
dorsal, an infant feeding tube was passed through the dorsal urethral
meatus and an adaptor was attached to the ventral urethral meatus. Both
urethrae were then simultaneously flushed with normal saline, under
real-time ultrasound, which showed saline entering the urinary bladder
through two separate channels (Figures 4 and 5). No plaques or
calcifications along these urethral channels were detected on ultrasound
examination. A detailed ultrasound evaluation of the abdomen was done,
which revealed both the kidneys to be normal in position and normal in
size, shape and echo texture. There was no hydronephrosis or hydroureter
bilaterally. Magnetic resonance imaging (MRI) was undertaken for further
anatomical delineation of this entity and to rule out any associated
vertebral anomalies. Infant feeding tubes were passed through both
urethrae, so as to distend them. Routine T1WI and heavily weighted T2WI
in axial and coronal plane were obtained with both infant feeding tubes
in position, which were seen entering the bladder through two completely
different urethral channels (Figures 6 and 7).
Urethral duplication is a rare congenital anomaly with approximately 200 cases described in literature.1
Most of the reported cases are that of incomplete duplications.
Complete duplication is rare only 20 cases have been reported until now.2 This anomaly is most common in males and very few cases have been reported in females.1-7
Several theories have been proposed to explain urethral duplication,
including, misalignment of the termination of the cloacal membrane with
the genital tubercle.3 However, no single theory seems to
explain all the various types of anomalies. Most patients are
asymptomatic except for a double stream, though some of them can present
with urinary tract infections, incontinence and bladder outflow tract
obstruction. A child may be brought, by the mother, just because of the
dorsal opening. Genitourinary anomalies and lumbar spine anomalies of
the colon have been reported to be associated with this condition.4 There have been various attempts to classify urethral duplication. The most commonly used classification is by Effmann et al.8 (Figure 8) This classification is functional, however it does not distinguish sagittal from coronal duplications.1 According
to this classification, our case belonged to type 2A-1. In Woodhouse
and Williams classification, sagittal and coronal duplications were
categorized, but anatomical details were not well addressed.7
Urethral duplication is rarely associated with bladder duplication,
which is then, more commonly a coronal or saggital duplication.5 In contrast with bladder duplication, urethral duplication is more commonly saggital.3 It
is important to recognize and preserve the functional urethra, which is
usually wide in caliber with good sphincteric function and normal
verumontanum. Differential diagnosis for duplication of urethra should
include fistulous tract resulting from instrumentation, operative
procedures and infections. Dynamic retrograde urethrography and
micturating cystourethrography are being used for urethral imaging.
However, as these procedures are associated with exposure to radiation,
an alternative imaging modality like sonourethrogram is being evaluated
and fast gaining acceptance. Sonourethrogram has definite advantages in
that it isa real-time study with no radiation hazards and does not use
iodinated contrast media. It can also be used to detect any plaques and
calcifications, which could be associated with chordee.
in delineating urethral and periurethral soft tissues noninvasively with
routinely used sequences such as T1WI and heavilyT2 WI in axial,
sagittal and coronal plane. In congenital anomalies it is mainly
reserved for intersex anomalies and complex genitourinary anomalies. The
multiplanar capability and excellent soft tissue contrast offered by
MRI are definite advantages, however, cost and availability are
Sonourethrogram and MRI are now being used as an
adjunct to voiding cystourethrography and retrograde urethrography in
urethralimaging. To our knowledge this is the first case report
describing the features of complete duplication of urethra on
sonourethrogram and MRI.
Knowledge of urethral duplication is
important with respect to surgical procedures. Surgery should be
considered in patients with annoying symptoms, such as double stream or
cosmetic deformity, such as epispadiac meatus. Treatment should aim at
restoring the functional normalcy of the genitourinary tract and
correction of the chordee, when present, should be undertaken. Surgical
management should be tailored to the individual type of duplication. The
outcome is usually favorable in most cases.
Urethral duplication, although extremely rare, has long been one of most
intriguing of congenital anomalies. Apart from normal radiological
procedures of dynamic retrograde urethrography and cystography, we have
attempted to present the sonourethrogram and MRI features of this
clinical entity, which, to our knowledge, has not been mentioned in the
literature. A complete knowledge of the anatomy of the anomaly helps the
treating surgeon to better plan his approach.
- Pippi Salle JL, Sibai H, Jacobson AI,
et al. Bladder exstrophy associated with complete urethral duplication: A
rare malformation with excellent prognosis. J Urol. 2001;165 (6 Pt 2): 2434-2437.
Gupta NP, Ansari MS, Aron M, Mandal S. Y duplication of urethra with
complete atresia of the orthotopic channel: 1-stage reconstruction. J Urol. 2000;163:949-950.
- Pippi Salle JL, Sibai H, Rosenstein D, et al. Urethral duplication in the male: Review of 16 cases. J Urol. 2000;163:1936-1940.
- Dajani AM, eL-Muhtasseb H, Kamal MF. Complete duplication of the bladder and urethra. J Urol. 1992;147:1079-1080.
AO, Senocak ME, Büyükpamukçu N, Hiçsönmez A. Complete duplication of
the bladder and urethra: A case report and review of the literature. J Pediatr Surg. 1995; 30:1605-1606.
- Rabinovitch HH. Urethral duplication. Reconstructive surgery. Webster G, Kerby R, Goldwasser B, eds. Oxford:Blackwell Scientific Publications. 1993: Ch56,795-803.
- Woodhouse CR, Williams DI. Duplications of the lower urinary tract in children. Br J Urol. 1979; 51:481-487.
- Effmann EL, Lebowitz RL, Colodny AH. Duplication of the urethra. Radiology. 1976;119:179-185.