Posterior urethral valves are abnormal congenital membranes in the male urethra that obstruct normal bladder emptying. They are the most common cause of bladder outlet obstruction in boys. Type I valves, which account for 95% of cases, involve a bicuspid valve that radiates from the posterior urethra. A voiding cystourethrogram is the best way to diagnose valves and shows valve leaflets and other signs of obstruction. Treatment involves primary valve ablation or creating vesicostomies or uretrostomies to bypass the obstruction. Long term sequelae like renal disease are significant, so monitoring is important.

1. Posterior Urethral Valve

2. Overview
Epidemiology
Classification
Diagnosis
Treatment
Conclusion
References
Contents

3. Overview
Epidemiology
Classification
Diagnosis
Treatment
Conclusion
References
Contents

4. - A (PUV) is an abnormal congenital obstructing
membrane that is located within the posterior male
urethra; this valve is the most common cause of
bladder outlet obstruction in male children. [1, 2, 3]

5. - The valve is believed to result from abnormal
embryologic development of the fetal posterior
urethra.
- These valves essentially obstruct normal bladder
emptying. This mechanical obstruction increases
voiding pressures and may alter normal
development of the fetal bladder and kidneys.

7. - Children with higher degrees of obstruction
present earlier with the most severe
symptoms.
- A spectrum of signs and symptoms, ranging
from mild obstructive symptoms of voiding
dysfunction to severe obstruction with resultant
renal failure and pulmonary hypoplasia , may be
noted. (3)

8. Overview
Epidemiology
Classification
Diagnosis
Treatment
Conclusion
References
Contents

9. Incidence :
- 1 per 5000 to 8000
- More than 50 % are diagnosed in the 1st year
with more severe obstruction .

10. - Renal insufficiency is caused by PUVs in
approximately 10-15 % of children
undergoing renal transplant .
- approximately 1/3 of patients born with
PUVs progress to end stage renal disease
(ESRD)

12. Overview
Epidemiology
Classification
Diagnosis
Treatment
Conclusion
References
Contents

13. - The classic categorization
of posterior urethral valves
into types I, II, and III was
developed by H. H. Young in
1919[4] and has undergone
modification over time based
on clinical observation and a
better understanding of the
embryologic events that lead
to normal urethral
development.

14. Type I PUV
- Type I valve accounts for 95 % of all valves
- Secondary to abnormal insertion and absorption of most distal
aspects of the Wolffian ducts during bladder development .

15. - Bicuspid valve that radiates distally from the
posterior edge of the verumontanum to the anterior
proximal membranous urethra

16. Type II PUV
- Very infrequent
- Non obstructive urethral
folds
- It's thought to be a sequela of
voiding dysfunction ,
- therefore these valves can
be differentiated from Type I
& Type III valves by their
location proximal to the
verumontanum (extends
proximaly from the
verumontanum to the

17. Type III PUV
- Membrane in the posterior
urethra believed to originate
from incomplete canalization
between the anterior &
posterior urethra.
- This valve is a
circumferential membrane or
diaphragm that is located at
the membranous urethra .
- Type III valves account for
almost 5 % of all valves
- Worst Prognosis (1)

19. Overview
Epidemiology
Classification
Diagnosis
Treatment
Conclusion
References
Contents

20. Voiding cystourethrogram
(VCUG)
is the best imaging technique for the
diagnosis of PUV and can show :
- visualizations of the valve
leaflets
- Thickened & trabeculated
bladder
- Dilated or elongated posterior
urethra
- Hypertrophied bladder neck
- Diverticula
- Vesicoureteral reflux and reflux into the ejaculatory ducts
secondary to elevated bladder and urethral pressure

23. Associated findings
- VUR 40 %
- Renal dysplasia
- hydroureteronephrosis
- ARF

24. Antenatal & Postnatal Ultrasound
- Marked distention and hypertrophy of the bladder
- Hydronephrosis and hydroureter may or may not be present
- In severe cases oligohydramnios and renal dysplasia (2)
- Keyhole sign may be seen on ultrasound due to the distention of
both the bladder and the urethra immediately proximal to the valve(5) .
** Unfortunately, such findings are generally not seen before 26 weeks
of gestation. (5)

27. Delayed presentation
- UTI
- Diurnal enuresis in boys older than 5 years
- Secondary diurnal enuresis
- Voiding pain or dysfunction
- Decreased force of stream may indicate the
presence of PUVs
- Discovered during evaluations of abdominal mass
or renal failure.

28. Differential Diagnosis
- In this age group and with clear dilatation of the
posterior urethra there is usually little differential other
than urethral atresia, which is far less common (2).
- When only the bladder is clearly abnormal - thick walled
and trabeculated, other conditions to be considered
include (5):
* Neurogenic bladder
* Prune-belly syndrome

29. Overview
Epidemiology
Classification
Diagnosis
Treatment
Conclusion
References
Contents

30. Primary Valve ablation
Vesicostomy
Cutaneous uretrostomies
Antireflux Surgery
Surgical Treatment

31. Medical Treatment :
- Antibiotics
- Correction of Metabolic disturbances

32. Primary valve ablation

33. Vesicostomy

34. Cutaneous Uretrostomies

35. Overview
Epidemiology
Classification
Diagnosis
Treatment
Conclusion
References
Contents

36. - PUV has 3 types I , II &III
- Type I is the most common , Type III has the worst
prognosis.
- A spectrum of signs and symptoms, ranging from mild
obstructive symptoms of voiding dysfunction to severe
obstruction with resultant renal failure and pulmonary
hypoplasia.
- Long term sequelae are significant especially renal
disease.
- VCUG is the best modality of diagnosis.
- Majority are managed by valve ablation

37. Overview
Epidemiology
Classification
Diagnosis
Treatment
Conclusion
References
Contents

38. 1. Berrocal T, López-pereira P, Arjonilla A et-al. Anomalies of the distal ureter,
bladder, and urethra in children: embryologic, radiologic, and pathologic features.
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when. Churchill Livingstone. (2004) ISBN:0443054711.
4. Bruyn RD. Pediatric ultrasound, how, why and when. Churchill Livingstone. (2005)
ISBN:0443072752.
5. Haller JO, Slovis TL, Joshi A. Pediatric radiology. Springer Verlag. (2005)
ISBN:3540213546.
6. Blews DE. Sonography of the neonatal genitourinary tract. Radiol. Clin. North Am.
1999;37 (6): 1199-208, vii. –
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