Content by: Barkha Boral, Yatee Samantaray
Design by: Saachi Kurudi
Web post by: Elvin Joshua Pinto
What exactly is Bladder Exstrophy?
It is rare congenital condition, part of the exstrophy-epispadias complex (EEC), where the bladder develops outside the body through an opening in the abdominal wall.
The primary defect in exstrophy is a derangement in midline development that presents with a spectrum of severity.
The anomaly of exstrophy bladder not only involves the urinary tract and genital system but also the musculoskeletal system of the lower abdomen and pelvis.
How does this happen?
In exstrophy, the penile and the scrotal skin are interposed by a band of skin of some breadth with little or no pigmentation. It has been proposed that the exstrophy of the bladder is the result of the cephalad origin of the genital tubercle. This in turn has a wedge effect and produces interference with the medial migration of the mesoderm and prevents cloacal migration in both the dorsal and caudal direction.
Many congenital anomalies correspond to the normal embryonic stage, that is, the eventual deformity is essentially present at some stage in the normal embryo. However, exstrophy bladder is never present as a normal developmental stage nor has been recognized in abnormal embryos, which suggests it is not caused by a simple developmental arrest.
Complications
This rare genetic defect presents multiple concerns such as:
- Urinary incontinence
- Recurrent UTIs due to abnormal flow or incomplete bladder emptying
- Vesicourethral reflux (VUR)- Reflux of urine from the bladder into the ureters and kidneys
- Recurrent UTIs, VUR, and high bladder pressures can progress to renal dysfunction over time
- Potential risk of adenocarcinomas.
- Short, pendular penis in males
- In females, less complex- shorter and stenotic vagina, bifid clitoris may be present.
- Increased distance between the hips, waddling gait, outward rotation of the lower limbs
What do we do now?
Management involves surgeries that encompass multiple procedures aimed at reconstructing the bladder, the lower abdominal wall defect, and optimal genital reconstruction with functional and cosmetically acceptable outcomes while maximizing the possibility of future continence with bladder neck reconstruction. There are three main procedures:
Primary closure
- Surgical procedures are done within the first 48-72 hours of life involving only the closure of the bladder, abdominal wall, and urethra, often without addressing continence or genital reconstruction at this stage.
- Primary closure can be part of either a staged or single-surgery approach.
Staged Repair
- First Stage: Early closure of the bladder and abdominal wall with or without osteotomies to close the pelvic bone done soon after birth.
- Second Stage: Epispadias repair.
- Third Stage: Bladder neck reconstruction to achieve continence done around 4-5 years of age.
Complete Primary Repair of Exstrophy (CPRE)
- It is a modern approach where all components of bladder exstrophy are addressed in a single operation.
- Aim: to address bladder closure, bladder neck reconstruction for continence, and epispadias repair for functional and cosmetic external genitalia.
- It is typically done within 72 hours of life.
How is CPRE performed?
1. Bladder Closure and Mitchell Penile Disassembly (Epispadias repair)
The entire length of the urethral plate and bladder is marked. Picture below.
Dissection is done along the lateral aspect of the urethral plate, above the Buck’s Fascia, using the perivesical fat as a landmark. Picture below.
This is followed by dissection of the ventral skin from the penis.
Corpus Spongiosum is left attached to the urethral plate since it has a common blood supply. Tunica albuginea is dissected.
The lateral margins of the Urethral plate and Corpus Spongiosum are dissected from the corpora cavernosa proximally.
The corpora cavernosa is completely disassembled up to the intersymphyseal band.
The band is then divided on both sides. This division of the band allows posterior placement of the bladder without tension.
The prostatic urethra, bladder, and bladder neck are placed deep into the pelvis
- The corpora cavernosa is now brought together and the urethra is brought underneath.
- The CC is brought together by suturing the edges of the buck’s fascia. Picture below.
- The urethra is now ventrally present.
- Some meatus may still be hypospadiatic.
2. Bladder Neck Reconstruction (Mitchell’s BNR)
1j Dotted lines represent incisions that will construct the posterior bladder strip that will become the urethra.
2) Using a retractor, the inferior most portion of the bladder is enlarged. Ureters detached from bladder.
3) Posterior strip and bladder closed. Ureters are now attached to a higher position.
This is done to achieve maximum possible continence in such individuals. The neck of the urethra is narrowed to maintain outlet resistance while preserving bladder cycling function.
3. Pelvic Osteotomy
- Done to correct the musculoskeletal deformity (if pubic diastasis > 4cm)
- The patient is placed in a Spica cast for immobilization
After all this CPRE is concluded with suturing of the rectus fascia and the skin is closed in the midline.
An umblicoplasty may be done for aesthetic concerns.
CONCLUSION: Bladder exstrophy is a rare congenital condition where the bladder protrudes through the abdominal wall. The precise cause remains unclear, as it doesn’t align with known embryonic developmental stages. Management typically involves complex surgical interventions aimed at reconstructing the bladder and associated structures. The Complete Primary Repair of Exstrophy (CPRE) is a modern approach that consolidates these repairs into a single operation to improve function and aesthetics, addressing bladder closure and continence.