The laparoscopic excision procedure for bladder endometriosis involves six steps, starting with a cystoscopy and ending with bladder mobilisation for nodule excision.
Excision requires careful bladder dissection, ureterolysis for nodule mobilisation, and nodule excision using cystoscopic guidance.
The surgical defect closure is tension-free and full-thickness. A water-leak test checks for any closure defects.
Post-surgery, a urinary catheter stays in place for 7-21 days for healing. For large cystotomies, a retrograde cystogram is advised before catheter removal. A standardised, team-based approach ensures safe excision.
This video presents a stepwise approach to the laparoscopic excision of bladder endometriosis by partial cystectomy.
Anatomy of the Bladder
Anatomically, the bladder is a midline pelvic organ that consists of two regions, the bladder dome, which is mostly intraperitoneal, and the bladder base, which is extraperitoneal and contains a triangular area called the trigone. The trigone is a key surgical landmark, as each of its vertexes embody a bladder opening, and, therefore, invasion of endometriosis into or very near the structure may necessitate a ureteral reimplantation.
The bladder wall consists of four layers, the mucosa or urothelium, the submucosa or lamina propria, the detrusor muscle or muscularis propria and the serosa or adventitia. For these layers in mind, bladder endometriosis is defined as the presence of endometrial glands and stroma in the muscularis propria, that is in the detrusor muscle.
Prevalence and Diagnosis of Urinary Tract Endometriosis
Urinary tract endometriosis affects approximately 1% of women with endometriosis and most commonly involves the bladder, followed by the ureters and, rarely, the kidneys. Ultrasonography remains a first-line imaging modality for the identification and surgical planning of suspected bladder endometriosis. It should describe the lesion location, size and depth of infiltration.
Three Step Surgical Approach to Bladder Endometriosis
The surgical approach to excise bladder endometriotic by laparoscopy can be summarised in six steps.
Step One – Initial Cystoscopy and Ureteral Stent Placement
Conjointly with the urology team in the OR, a cystoscopy is performed as a first step, to delineate the borders and depth of infiltration of the bladder lesion. Insertion of temporary ureteral stents can allow easier identification of the ureteral orifices later during the abdominal portion of the surgery.
Step Two – Abdominal Survey and Treatment of Associated Endometriosis
As 88% of bladder endometriosis is associated with some other form of endometriosis, a thorough abdominal survey must be routinely performed at the time of laparoscopy. If present, posterior compartment disease can be treated first, and, if indicated, a hysterectomy can be performed prior to tackling the bladder disease.
Step Three – Mobilisation of the Bladder for Nodule Excision
Mobilising the bladder to free the nodule margins represents the most important step of the surgery. This can be achieved through the dissection of four potential spaces that surround the bladder. The vesicovaginal space posteriorly, the paravesical spaces laterally and the space of Retzius anteriorly.
Specific Surgical Techniques
For this lead and extending to the posterior wall, the vesicovaginal plane is dissected first.
Technique for Vesicovaginal Plane Dissection
The bladder flap is opened and dissection is pursued beyond the margins of the nodule, as this will allow a complete nodule excision as well as a tension-free defect closure. In the case of this left posterolateral bladder nodule, incorporating the left round ligament and adnexum, a left ureterolysis is required in order to mobilise the nodule.
Technique for Ureterolysis and Nodule Mobilisation
The ureterolysis is pursued into the area of fibrosis, allowing the nodule to be freed prior to excision. For anterior nodules, the space of Retzius can be dissected to mobilise the bladder dome. After proper mobilisation, a cystoscopy is performed to guide the nodule excision by delineating the nodule edge from the mucosal side. The excision starts with incision into the bladder at the upper edge of the lesion, where the cystoscope light is pointing.
Technique for Nodule Excision and Cystotomy
Entry into the bladder lumen is evidenced by the leakage of fluid. The cystotomy is enlarged to allow a laparoscopic evaluation of the bladder lumen and identification of the internal ureteric orifices. The excision of the nodule is then pursued circumferentially, while keeping the nodule under tension, taking care to incorporate all fibrotic tissue, while maximining preservation of healthy tissues.
Technique for Defect Closure
A complete excision is essential to minimise the risk of recurrence. The cystotomy defect is closed in a horizontal fashion to avoid kinking of the ureters. Closure must be tension-free and incorporate the full thickness of the bladder wall. Closure can be performed in a single or double running layer of absorbable sutures, such as 2-0 monofilament or braided synthetic sutures.
Finally, a water-leak test by diluted methylene blue is performed to identify closure defects. Although water tightness is not necessary.
Postoperatively, indwelling urinary catheter should be left in-situ to allow healing for 7 to 21 days, depending on the defect size and location. A retrograde cystogram prior to catheter removal should be considered, especially for large cystotomies.
The safe and complete excision of bladder endometriosis relies on the understanding of surgical planes and pelvic spaces, the multidisciplinary aspect of patient care, and the standardisation of the surgical approach in six reproduceable steps.