AUTHOR AND EDITOR INFORMATION

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INTRODUCTION

Section 2 of 10  

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Background

This article discusses some of the more common bladder anomalies, such as bladder diverticula, and some of the uncommon bladder anomalies, such as bladder ears, congenital hypoplasia of the bladder, megacystis, bladder agenesis, duplication anomalies of the bladder, and finally, bladder septa. A discussion of urachal anomalies (ie, urachal sinus, urachal cyst, urachal diverticulum, patent urachus) is also included.

Pathophysiology

The timing of altered embryogenesis leading to these conditions has been a matter of speculation, and the embryologic cause of these lesions is unknown. Bladder development occurs during the fifth to seventh week of gestational development. Development depends upon many factors, such as proper mesenchymal differentiation, mesenchymal growth, urine production that stimulates bladder expansion, and detrusor contraction. Bladder cycling, the process of sequential expansion and contraction, is important in the anatomic and physiologic development of the normal bladder. Bladder ears are considered a normal variation, not a congenital anomaly.

Frequency

United States

Bladder diverticula are uncommon, but not rare. In a series of over 5000 children studied, the approximate incidence was 1.7%. All of the other entities are uncommon or rare.

Mortality/Morbidity

Most of these conditions have a low mortality rate and little morbidity.

• Bladder diverticula and vesicourachal diverticula often cause no symptoms, but in symptomatic cases, patients most often present with urinary tract infection. Rarely, bladder diverticula and vesicourachal diverticula may cause bladder outlet obstruction. Death from peritonitis due to a ruptured infected urachal cyst has been reported in a few cases, but most bladder anomalies are incidental findings, and patients are asymptomatic.
• Patent urachal anomalies do not usually cause significant morbidity or mortality. However, adenocarcinoma has been reported in adults in urachal remnants, presumably from chronic inflammation and infection.
• Bladder agenesis generally is incompatible with life.
• Megacystitis, bladder duplication, and bladder septation are rare. Morbidity of these conditions is generally related to associated abnormalities (when present) such as high-grade vesicoureteral reflux or renal dysplasia.
• Only 50 reported cases of bladder duplication exist.
• Bladder septations are equally rare.

Sex

All of these anomalies are infrequent or rare, and each condition occurs in both males and females. Data are insufficient to provide reasonably accurate frequency differences in the sexes.

Age

Bladder anomalies are generally diagnosed in infancy or childhood. With the advent of prenatal ultrasonography, such abnormalities are fully evaluated after birth. When not detected by antenatal screening, most are discovered in the evaluation of a urinary tract infection or, in the case of urachal anomalies, periumbilical drainage or redness.

CLINICAL

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History

• Bladder diverticula are herniations of the bladder mucosa through bladder wall musculature (detrusor muscle). Diverticular size can vary greatly, with some attaining a size equal to or greater than the volume of the bladder. Diverticula can be wide or narrow mouthed, as dictated by the size of the musculature (detrusor) defect. The size of diverticular openings has functional implications because narrow-mouthed diverticula often empty poorly. Stasis of urine within diverticula can also lead to stone formation or epithelial dysplasia.
• • Depending on the size and location, bladder diverticula may cause ureteral obstruction, bladder outlet obstruction, or vesicoureteral reflux. Ureteral obstruction is unusual, occurring in approximately 5% of children with bladder diverticulum. Bladder outlet obstruction is rare. However, vesicoureteral reflux is more common, affecting from 8-13% of patients.
  • Bladder diverticula most commonly occur lateral and superior to the ureteral orifices. They may also occur at the dome of the bladder, particularly in such disorders as bladder outlet obstruction (ie, posterior urethral valves) or Eagle Barrett syndrome (prune belly syndrome).
  • Bladder diverticula may be congenital or acquired. In the pediatric population, most cases are congenital. Congenital deficiency or weakness in the Waldeyer fascial sheath has been implicated as a cause. Congenital diverticula tend to be solitary and are located at the junction of the bladder trigone and detrusor. This anatomic location, close to the insertion of the ureter to the bladder, is important because large diverticula can impinge upon or distort the ureteral orifices. Therefore, undertake surgical excision of these diverticula with care to avoid injuring the ureter.
  • Acquired diverticula are the result of obstruction, infections, or iatrogenic causes. They tend to be multiple and occur in trabeculated bladders. Examples of loci of obstruction include posterior urethral valves, anterior urethral valves, urethral strictures, neuropathic bladder, and external sphincter dyssynergy. An example of iatrogenic diverticula is herniation of the bladder mucosa through the ureteral hiatus after antireflux surgery because of inadequate closure of the ureteral hiatus. Many diverticula that are related to obstruction spontaneously resolve after relief or correction of the obstruction. In some cases, the diverticula that occur in response to obstruction serve a beneficial function by acting as pressure pop-off mechanism, protecting the kidney and ureters from high pressures.
  • Some children with diverticula have voiding dysfunction on urodynamic testing. Whether the voiding dysfunction leads to the formation of diverticula or the presence of diverticula leads to voiding dysfunction is unclear.
• A urachal sinus derives from a persistently patent urachus. The sinus drains to the umbilicus, and this drainage often is the result of episodic infections of the sinus, resulting in the appearance of purulent drainage at the umbilicus. Children may present with periumbilical tenderness, a wet umbilicus, or granulation tissue at the level of the umbilicus. In many instances, these children have undergone multiple sliver nitrate cauterizations under the mistaken notion that this is simply granulation tissue after severance of the remnant umbilical cord.
• Urachal cyst is a fluid-filled structure occurring in between the two obliterated ends of the urachus, ie, the umbilicus and bladder dome. Most occur in the distal third of the urachus. In infancy, such cysts are rarely symptomatic, but they are detected with increasing frequency as an incidental finding during bladder ultrasonography in children undergoing evaluation for other reasons (eg, prenatal hydronephrosis, urinary tract infections). More commonly, the urachal cyst is detected in early childhood or adolescence. Symptoms are generally related to infection and the resultant inflammation and include suprapubic mass, fever, pain, and bladder or irritative voiding symptoms. Staphylococcus aureus is the most common bacterial organism. The peritoneum alone separates the cyst from the intra-abdominal cavity, so the inflammatory process may involve the adjacent intra-abdominal contents, resulting in abdominal pain. Death from intra-abdominal rupture has been reported.
• A patent urachus is a communication from the umbilicus to the bladder. Infants present with continuous or intermittent drainage from the umbilicus. Crying, straining, voiding, or the prone position may accentuate intermittent drainage. The tract may become inflamed, resulting in tenderness, periumbilical swelling, and serosanguinous or purulent discharge. The patent urachus may also be associated with bladder outlet obstruction, such as posterior urethral valves. Correction of the obstruction may result in the spontaneous resolution of the patent urachus. However, if the patent urachus persists beyond several months after relief of the obstruction, it should be surgically corrected.
• Vesicourachal diverticulum is an outpouching at the apex of the bladder that results from incomplete closure of the proximal urachus. Most patients are asymptomatic because the diverticula drain well with bladder emptying. Often, vesicourachal diverticula are incidentally discovered during evaluation for other reasons. Rarely, they become large and empty poorly, resulting in recurrent urinary tract infections or stone formation.
• Bladder ears are lateral protrusions of the bladder through the internal inguinal ring and into the inguinal canal. In infants, the bladder assumes a more abdominal position, which places it in close proximity to the internal inguinal ring. With growth, the pelvis becomes more developed, and the bladder assumes a more pelvic position. Therefore, this is rarely observed in adults. Bladder ears are often observed during voiding cystourethrography (VCUG) or intravenous pyelography (IVP), when the bladder is filled to capacity. Bladder ears have also been seen on CT body imaging. Knowledge of this entity is important to surgeons during inguinal herniorrhaphy because occasional reports have been made of partial or near total cystectomy performed under the mistaken notion that this was a large hernia sac.
• Bladder agenesis is rare (approximately 45 reported cases) and generally incompatible with life. Fewer than 20 cases have been reported in live births, and all have been females, presumably because they have less outlet resistance than males, resulting in some preservation of renal function. Ureters may enter into the urethra, vagina, Gartner duct cyst (female), prostatic urethra, rectum, or the patent urachus. Most often, associated hydroureteronephrosis and renal dysplasia (variable) are present. Other associated anomalies include neurologic, orthopedic, hindgut, and other urogenital anomalies, such as renal agenesis and absence of the prostate, vagina, seminal vesicles, epididymis, or penis.
• Megacystitis is often discovered postnatally when completing the evaluation of prenatal hydronephrosis. Febrile urinary tract infection is the other common presentation. Megacystitis is an enlarged bladder, believed to be secondary to overfilling of the fetal bladder during development. This condition is associated with massive high-grade vesicoureteral reflux, which may also be the etiology of megacystitis. In the presence of massive reflux, a large percentage of the voiding bladder volume is refluxed into the upper tracts. This causes constant recycling of the urine between the bladder and ureters, resulting in progressive dilation of both. Megacystitis can be observed in other conditions, such as posterior urethral valves, Ehlers-Danlos syndrome, urethral diverticulum, microcolon hypoperistalsis syndrome, sacral meningomyelocele, sacrococcygeal teratoma, and pelvic neuroblastoma.
• Bladder duplication is rare, with fewer than 50 cases reported. Duplication can be complete or partial, with complete duplication more common than incomplete duplication. The 2 halves of the bladder are on either side of the midline, with the corresponding ipsilateral ureter draining each bladder half. Associated anomalies occur with much greater frequency in complete bladder duplication, including duplication of the penis, vagina, uterus, lumbar vertebrae, and hindgut. In addition, fistulas may be present between the rectum, vagina, and urethra. With complete bladder duplication, 2 urethras exist. With incomplete bladder duplication, the bladder joins distally into one common urethra.
• Bladder septation anomalies are rare. Fibromuscular or mucosa septations divide the bladder into equal or unequal portions. Septations may be complete or incomplete. Functioning of the associated renal units depends on adequacy of upper tract drainage.

Physical

For many of the bladder anomalies, no overt physical findings are observed. They are elucidated after radiologic imaging for such things as a history of prenatal hydronephrosis or urinary tract infections. Physical findings relative to each of the anomalies are as follows:

• Bladder diverticula - None
• Urachal sinus - Intermittent drainage from umbilicus (may be serous or serosanguinous)
• Urachal cyst - None (With infected cyst, physical findings include infraumbilical or suprapubic mass with tenderness or erythema of overlying skin.)
• Patent urachus - Intermittent umbilical drainage (may be serous or urine)
• Vesicourachal diverticulum - None
• Bladder ears - None
• Bladder agenesis - None (Most physical findings pertain to various associated anomalies.)
• Megacystitis - None
• Bladder duplication - None (In complete bladder duplication, 2 urethral openings may be identified.)
• Bladder septation - None

Causes

See Pathophysiology.

DIFFERENTIALS

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Other Problems to be Considered

Patent urachus
Granulation tissue of a healing umbilical stump
Patent omphalomesenteric duct
Urachal sinus
Infected umbilical vessel

WORKUP

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Lab Studies

• Bladder diverticula - None
• Urachal sinus - None
• Urachal cyst - None
• Patent urachus - Analysis of the umbilical drainage for creatinine or urea to determine if the values are consistent with urine may help differentiate the patent urachus from other entities listed in the differential diagnosis.
• Vesicourachal diverticulum - None
• Bladder ears - None
• Bladder agenesis - Serum electrolytes, creatinine
• Megacystitis - Urine culture, serum creatinine
• Bladder duplication - Urine culture, serum creatinine
• Bladder septation - Urine culture, serum creatinine

Imaging Studies

• Bladder diverticula: VCUG is the best imaging modality. Bladder ultrasonography may also be used to detect bladder diverticula but does not provide the same anatomic definition as the VCUG. IVP may detect bladder diverticula, particularly those that protrude laterally. Anteriorly or posteriorly placed diverticula may be obscured from view because they are overshadowed by the contrast within the bladder (see Images 1-3).
• Urachal sinus: Sinography is the best test to detect urachal sinus. Other less sensitive tests include ultrasonography, computed axial tomography (CT) scanning, or magnetic resonance imaging (MRI).
• Urachal cyst: Ultrasonography is the best test for detecting urachal cyst. CT scanning or MRI can help to delineate the size and location of the cyst. In addition, with infected urachal cysts, CT scanning is used to determine involvement of adjacent structures secondary to the inflammatory mass (see Images 4-5).
• Patent urachus: VCUG may demonstrate a patent urachus in addition to identifying any evidence of bladder outlet obstruction or vesicoureteral reflux.
• Vesicourachal diverticulum: VCUG is the most useful test. This test is used to identify any evidence of bladder outlet obstruction or vesicoureteral reflux.
• Bladder ears: This anomaly can be incidentally discovered with VCUG or IVP.
• Bladder agenesis: Full evaluation is best performed with IVP and VCUG. These 2 tests delineate both upper tract and lower tract anatomy.
• Megacystitis: VCUG is the best test to demonstrate the enlarged bladder and massive refluxing megaureters. Additional studies, such as nuclear medicine renal scanning, are helpful in determining renal function (see Image 6). Cystography and urodynamic studies may be necessary in those children with voiding dysfunction such as incomplete bladder emptying, frequent cystitis, or incontinence.
• Bladder duplication: The full evaluation is best performed with IVP and VCUG. These 2 tests delineate both upper tract and lower tract anatomy (see Images 7-9).
• Bladder septation: This condition may often require several imaging modalities, including VCUG, IVP, and bladder ultrasonography, to fully delineate the anatomy.

Procedures

• Infected urachal cyst: In some instances, percutaneous drainage of the infected cyst is necessary as a temporary measure. After percutaneous decompression and adequate antibiotic therapy, complete surgical excision of the urachus is necessary.

TREATMENT

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Medical Care

• Bladder diverticula: If present, correct bladder outlet obstruction because many bladder diverticula resolve spontaneously after relief of obstruction. Congenital diverticula are usually removed surgically.
• Urachal sinus: These can be observed in the first 4-8 weeks of life.
• Urachal cyst: For small asymptomatic cysts that are discovered incidentally, observation with serial ultrasonography may be appropriate.
• Patent urachus: Observation may be undertaken in the first few months of life because some cases may resolve spontaneously. Persistence after 2 months warrants surgical correction. If bladder outlet obstruction is present, correct this first because this may be the cause of the persistent patency of the urachus.
• Vesicourachal diverticulum: Most patients do not require treatment.
• Bladder ears: No treatment is necessary because nearly all resolve spontaneously.
• Bladder agenesis: This condition requires urinary diversion and subsequent reconstruction (eg, continent urinary reservoir).
• Megacystitis: Clean intermittent catheterization may be considered in those patients with incomplete bladder emptying or frequent urinary tract infections. In children in whom clean intermittent catheterization is instituted, urodynamic studies should be obtained. See "Surgical Care."
• Bladder duplication: Incomplete bladder duplication often does not require any treatment when the upper urinary tracts are normal and the bladder empties completely. If other associated anomalies are present, address them individually. See "Surgical Care."
• Bladder septation: Depending upon the anatomy, no treatment may be appropriate, for example, with a small incomplete septation with normal upper tracts and complete bladder emptying.

Surgical Care

• Bladder diverticula: Surgery is generally required when bladder diverticula cause obstruction, recurrent urinary tract infections, vesicoureteral reflux, or stone formation. Correct outlet obstruction first in patients with diverticula secondary to obstruction because some of these diverticula spontaneously resolve with relief of the obstruction. Surgical diverticulectomy for congenital diverticula may be approached extravesically or intravesically. The surgical approach varies depending on the size, location, associated anomalies (ie, vesicoureteral reflux), and surgeon's preferences. In very large paraureteral diverticula, take care to avoid injuring adjacent structures such as the ureter or vas deferens. In the presence of ureteral obstruction, renal function dictates management. If the associated kidney has little or no function, a nephrectomy with bladder diverticulectomy is performed. Perform diverticulectomy and ureteral reimplantation with adequate kidney function.
• Urachal sinus: Surgical correction involves complete removal of the urachus, from the umbilicus to the dome of the bladder. In an infant or child, this can be approached easily with a Pfannenstiel incision. In an infant, the distance from the dome of the bladder to the base of the umbilicus is very short. Complete removal eliminates any further problems. Plan surgical removal after adequate treatment of the infection because intraperitoneal structures may adhere to the urachus in the inflammatory process.
• Urachal cyst: After adequate treatment of infected urachal cyst, surgical removal of the entire urachus is warranted. A Pfannenstiel incision can be used in an infant or child. Again, in an infant, the distance from the dome of the bladder to the base of the umbilicus is very short. Complete removal eliminates any further problems.
• Patent urachus: As with urachal cyst, complete removal using the described technique eliminates any further problems.
• Vesicourachal diverticulum: Surgical removal is reserved for large symptomatic diverticula causing recurrent urinary tract infections, stones, or poor emptying.
• Bladders ears: Surgery is unnecessary because nearly all resolve spontaneously.
• Bladder agenesis: Initial treatment is urinary diversion. Complex urinary reconstruction, such as the creation of a continent urinary reservoir, may be undertaken later in life.
• Megacystitis: The massive vesicoureteral reflux is corrected by ureteral reimplantation, which usually involves tapering the ureters at the time of reimplantation. Correction of the megacystitis by reduction cystoplasty often is not necessary. Correction of the reflux alone may be sufficient. If recurrent urinary tract infections or incomplete bladder emptying occur after ureteral reimplantation, reduction cystoplasty may be considered. In rare instances, a vesicostomy can be performed as a temporary measure in those children with megacystitis and severe vesicoureteral reflux until a more formal reconstruction can be performed.
• Bladder duplication: Complete bladder duplication has a much higher incidence of associated anomalies necessitating surgical correction such as fistulas between the urethra and adjacent structures. The variable anatomy of each case dictates the surgical approach.
• Bladder septation: Surgical treatment is dictated by each patient's anatomy. The goals are to relieve bladder and upper tract obstruction.

Consultations

For all of the bladder anomalies, consultation with other professionals is dictated primarily by the presence of the associated anomalies. In situations of renal insufficiency with the various obstructive entities (eg, posterior urethral valves, neurogenic bladder), consultation with a nephrologist is advisable.

Diet

Generally, no dietary restrictions are needed for the various bladder anomalies. In cases of significant renal insufficiency, the nephrologist may impose certain dietary restrictions, such as limited protein intake.

Activity

No specific restrictions on activity are necessary.

FOLLOW-UP

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Further Outpatient Care

• Bladder diverticula: No follow-up care is required after surgical removal. Small diverticula that are treated by observation alone may be annually monitored with renal and bladder ultrasonography.
• Urachal sinus: No follow-up care is required after surgical removal.
• Urachal cyst: perform yearly ultrasonographic studies if small cysts are to be monitored. No follow-up is necessary after surgical removal.
• Patent urachus: No follow-up care is necessary after surgical removal.
• Vesicourachal diverticulum: No follow-up care is necessary.
• Bladder ears: No follow-up care is necessary.
• Bladder agenesis: Frequent outpatient follow-up visits are necessary after urinary diversion. Initially, outpatient follow-up care may occur as often as monthly. Once stable, follow-up visits usually are annual. Serial renal ultrasonographic evaluation is used to assess renal growth and the presence or absence of hydronephrosis. Conduit ultrasonography can detect the presence of stones. Serum electrolytes and creatinine help detect metabolic disturbances and renal insufficiency.
• Megacystitis: Yearly renal and bladder ultrasonographic evaluation may be appropriate until just after the toilet training period to monitor the upper tracts and ensure adequate bladder emptying.
• Bladder duplication: Yearly renal and bladder ultrasonographic evaluation may be appropriate, as described for megacystitis.
• Bladder septation: Yearly renal and bladder ultrasonographic evaluation may be appropriate, as described for megacystitis.

Deterrence/Prevention

• These conditions are congenital. The timing of altered embryogenesis leading to these conditions has been a matter of speculation, and the embryologic cause of these lesions is unknown.

Complications

• Complications are related to persistent obstruction or recurrent urinary tract infections, namely renal insufficiency or failure. If the obstruction is corrected and urinary drainage is unimpeded, long-term complications are minimal. In the case of bladder agenesis, the long-term complications are related to those specific to urinary diversion, continent reservoir, or both. These include ureteral stricture at the junction of the ureter and reservoir, reservoir stones, recurrent urinary tract infection, stomal stenosis of the catheterizable segment, and metabolic disturbances relative to the intestinal segment used.

Prognosis

• Bladder diverticula - Excellent
• Urachal sinus - Excellent
• Urachal cyst - Excellent
• Patent urachus - Excellent
• Vesicourachal diverticulum - Excellent
• Bladder ears - Excellent
• Bladder agenesis - Guarded
• Megacystitis - Good
• Bladder duplication - Good to excellent
• Bladder septation - Variable, guarded to good depending on anatomy and degree of renal dysfunction

Patient Education

• In all these conditions, an element of voiding dysfunction may exist. Educate parents regarding frequent and complete bladder emptying after the toilet training period to guard against infrequent and dysfunctional voiding patterns. In general, children should void approximately 5-6 times per day, which equates to voiding every 3 hours. Infrequent and dysfunctional voiding in the presence of an anatomic abnormality may place the child at increased risk for febrile urinary tract infections and renal damage.

MISCELLANEOUS

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Medical/Legal Pitfalls

• Knowledge of bladder ears is important to surgeons during inguinal herniorrhaphy because partial or near total cystectomy has occasionally been reported under the mistaken notion that the bladder ear was a large hernia sac.
• The anatomic location of congenital diverticula close to the insertion of the ureter to the bladder is important because large diverticula can impinge upon or distort the ureteral orifices. Therefore, undertake surgical excision of these diverticula with care to avoid injuring the ureter.

MULTIMEDIA

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Media file 1:  Voiding cystourethrogram showing a bladder diverticulum arising from the posterior aspect of the bladder.
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Media file 2:  Voiding cystourethrogram showing 2 posteriorly placed bladder diverticula.
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Media file 3:  Bladder ultrasound showing 2 posteriorly placed bladder diverticula.
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Media file 4:  Duplicated bladder with a urethral catheter placed into each bladder.
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Media file 5:  Voiding cystourethrogram demonstrating a duplicated bladder.
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Media file 6:  Intravenous pyelogram demonstrating a duplicated bladder. Notice how each ureter drains into the ipsilateral bladder.
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Media file 7:  Urachal cyst at the level of the umbilicus.
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Media type:  Photo

Media file 8:  Bladder anomalies. Ultrasound demonstrating urachal cyst. Ultrasound cursors mark the extent of the cyst.
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Media type:  Image

Media file 9:  Voiding cystourethrogram showing megacystitis. Bilateral vesicoureteral reflux is also observed (grade 3 on the right, grade 2 on the left).
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Media type:  X-RAY

REFERENCES

Section 10 of 10

• Authors and Editors
• Introduction
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• References

• Barrett DM, Malek RS. Observations on vesical diverticulum in childhood. Journal of Urology. 1976;116:234. [Medline].
• Blane CE, Serin JM, Bloom DA. Bladder diverticula in children. Radiology. 1194;190:695. [Medline].
• Burbige KA, Lebowitz RL, Colodny AH. The megacystis-megaureter syndrome. J Urol. Jun 1984;131(6):1133-6. [Medline].
• Burns E, Cummins H, Hyman J. Incomplete reduplication of the bladder. Journal of Urology. 1947;57:257.
• Caldamone AA. Anomalies of the bladder and cloaca. In: Gillenwater JY, Grayhack JT, Howards SS, et al, eds. Adult and Pediatric Urology. 2nd ed. St. Louis, Mo:. Mosby Year Book;1987:2023.
• Cilento BG, Nguyen HT. Bladder Diverticula, Urachal Anomalies, and Other Uncommon Anomalies Of The Bladder. In: Gearhart JP, Rink RC, Mouriquand P, eds. Pediatric Urology. Philadelphia, Pa:. WB Saunders;2001.
• Cilento BG Jr, Bauer SB, Retik AB. Urachal anomalies: defining the best diagnostic modality. Urology. Jul 1998;52(1):120-2. [Medline].
• Hutch JA. Saccule formation at the ureterovesical junction in smooth-walled bladders. Journal of Urology. 1961;86:390.
• Levard G, Aigrain Y, Ferkadji L. Urinary bladder diverticula and the Ehlers-Danlos syndrome in children. J Pediatr Surg. Nov 1989;24(11):1184-6. [Medline].
• Pieretti RV, Pieretti-Vanmarcke RV. Congenital bladder diverticula in children. Journal of Pediatric Surgery. 1999;34:468. [Medline].
• Shokeir AA, Ashamallah A, Abol-Enein H. Incomplete bladder duplication. Br J Urol. Jan 1995;75(1):106-7. [Medline].
• Stephens FD. The vesicoureteral hiatus and paraureteral diverticula. Journal of Urology. 1979;121:786. [Medline].
• Tacciuoli M, Laurenti C, Racheli T. Double bladder with complete sagittal septum: diagnosis and treatment. Br J Urol. Dec 1975;47(6):645-9. [Medline].
• Verhese DI, Belman AB. Urinary retention secondary to congenital bladder diverticula in infants. Journal of Urology. 1984;132:1186. [Medline].

Article Last Updated: May 18, 2006