Abstract
Introduction:
The objective of this study was to determine the outcomes associated with the endoscopic removal of foreign bodies (such as mesh or permanent suture) in the lower urinary tract after female stress incontinence surgery with the Holmium:YAG (Ho:YAG) laser, and to systematically review the literature on this topic.
Materials and Methods:
A retrospective chart review of 18 consecutive women found to have mesh or suture exposure was performed. All patients underwent Ho:YAG laser ablation. A systematic review was performed to identify literature addressing the endoscopic management of mesh/suture exposure after stress incontinence surgery.
Results:
Between November 2011 and February 2016, 18 women underwent Ho:YAG laser ablation of exposed mesh or suture. Presenting symptoms included lower urinary tract symptoms, pelvic pain, incontinence, or recurrent urinary tract infections. Thirteen women had a previous synthetic midurethral sling and five had a prior retropubic suspension. The median age was 58 years (interquartile range [IQR] 50–60) and median follow-up was 2 years (IQR 1–2). Four patients (22%) had residual mesh after the first procedure, requiring a repeat endoscopic procedure. Only one patient had a small amount of asymptomatic residual mesh on cystoscopy after the final procedure. Only minor postoperative complications were observed. Eight patients had stress incontinence and four underwent operative treatment for this. In our systematic review, we identified 16 case series, which described a total of 158 patients. Women most commonly presented with voiding symptoms or incontinence. Based on the synthesis of these data, repeat procedures were necessary in 16% and vesicovaginal fistula occurred in 2%. Recurrent/persistent stress incontinence was present in 20%, and of these patients, 3/4 underwent a new stress incontinence procedure.
Conclusions:
Both our case series and the systematic review of the literature demonstrated that endoscopic treatment of lower urinary tract foreign bodies after stress incontinence surgery has good success rates and minimal morbidity.
Introduction
F
Traditionally, surgical mesh or suture erosion has been managed with either transvaginal mesh excision for urethral erosions or an open cystotomy for bladder erosions. 3,4 Endoscopic ablation of eroded mesh or suture material offers a less invasive management option for patients. 5 The Holmium:YAG (Ho:YAG) laser is a multipurpose, multispecialty surgical laser used for a variety of endoscopic urology procedures. 6 It can ablate most materials and is able to fit through flexible and rigid endoscopic instruments. 6 Transurethral Ho:YAG laser ablation of eroded foreign material has been described in case reports and small retrospective case series with favorable outcomes and low morbidity. 5,7 –9
Our objective was to retrospectively review our experience with transurethral mesh and suture erosions treated exclusively with the Ho:YAG laser, and to perform a systematic review of the literature reporting outcomes of endoscopic ablation of mesh or suture exposure in the bladder or urethra after SUI procedures.
Methods
Case series
This is a retrospective case series of two surgeons' practices, who routinely offered Ho:YAG laser as an option for eroded mesh or suture material when appropriate. Our practice pattern involves conducting an initial consultation and performing an abdominal and pelvic examination and flexible cystoscopy. For this study, patients were identified using unique medical record codes that are associated with these cases. A retrospective chart review was carried out to identify all female patients with a history of incontinence surgery who underwent endoscopic laser ablation between November 2011 and February 2016. This study was approved by the Research Ethics Board at Western University (REB #106571).
Clinical and surgical records were reviewed, and a prespecified data collection sheet was used to extract patient and procedural data, including age, presenting symptoms, date and type of initial continence surgery, and time to presentation. When possible, the original operative report was reviewed to identify the procedure and the specific foreign body that was likely present. Cystoscopic findings such as the location and extent of mesh or suture erosions were also recorded as was the presence of any mesh encrustation or stones.
The treatment of the eroded mesh/suture was carried out under a general anesthetic. Patients were generally offered an endoscopic approach for all mesh or suture erosions that did not have any associated vaginal or urethral pathology (such as fistula or concomitant vaginal erosion). A rigid or flexible cystoscopy was used, and a 270–1000 μm Ho:YAG laser fiber was used depending on the amount of mesh and stone present, and the degree of angulation required if a flexible cystoscope was being used. Surgical data collected included total operative time, total laser energy used, and the need for further procedures beyond endoscopic laser ablation. Patients who underwent an attempted laser ablation, which required conversion to a transvaginal mesh excision, were included in our evaluation.
Postoperative outcomes and complications were assessed based on the entire available medical record between first procedure and last follow-up appointment. Patients underwent a follow-up cystoscopy approximately 3–6 months after the initial procedure to assess for a residual foreign material. After the initial follow-up cystoscopy, repeat cystoscopy or further surgical intervention was directed by clinical symptoms and physical examination.
Systematic review
An extensive literature search was performed, including the Cochrane Library, EMBASE, Google Scholar, MEDLINE, and PubMed. Search permutations included keywords and MeSH headings (holmium laser, mesh erosion, transurethral resection, endoscopic removal, and continence surgery, combined with Boolean operators such as “AND” and “OR” in search fields). Our primary inclusion criterion was an article describing an outcome or complication associated with endoscopic treatment of a lower urinary tract foreign body after female stress incontinence surgery. Journal articles were screened for content by stepwise review of the title, abstract, and full text for suitability by two authors. We further scrutinized the reference lists of extracted articles to identify additional references not retrieved by the initial search. Search was restricted to the English language literature, and there were no exclusions based on study design; however, articles were stratified by the number patients reported (due to the high risk of reporting bias, case reports of one or two patients were included in the Supplementary Data; Supplementary Data are available online at
Results
Patient demographics
Our retrospective chart review identified 18 women who underwent Ho:YAG endoscopic ablation of eroded synthetic material following incontinence surgery (Table 1). Twelve women had an erosion after a tension-free vaginal tape (TVT), one after an unspecified urethral sling, and five had sutures secondary to a prior RS.
LUTS = lower urinary tract symptoms; MMK = Marshall Marchetti-Krantz; NA = not applicable; OR = operating room; rUTI = repeated urinary tract infections; SUI = stress urinary incontinence; TVT = tension-free vaginal tape.
The median age of our patients was 58 years (IQR 50–60). The median time from original surgery to presentation for clinical assessment was 7 years (IQR 2–11). Women with RS presented later than those with TVT (median 11 vs 3 years). Primary presenting symptoms included LUTS (7), pelvic pain (5), SUI (3), and recurrent urinary tract infections (rUTIs, 6). Six patients were found to have intravesical erosion, four had erosion at the bladder neck, and eight had intraurethral erosion. Stone encrustation of the eroded mesh was present in 10 patients.
Operative management
All patients were treated endoscopically with Ho:YAG laser ablation of exposed mesh and suture material. Twelve patients were treated entirely transurethrally and two were treated in an antegrade manner through a suprapubic tract. All patients were treated on an outpatient basis with a median surgical time of 41 minutes (IQR 26–59). Median laser energy used was 1610 (IQR 865–4650) J. Retraction of the mesh or suture was used for improved visibility or access in four patients. This was accomplished by placing a Prolene suture through the mesh endoscopically or placing an endoscopic grasper or laparoscopic driver transurethrally to provide retraction. All women had a urethral catheter in place for 5–10 days postoperatively depending on the appearance of the urethra or bladder at the end of the procedure.
Patient outcomes
Postoperatively, 14 women (78%) had significant improvement or complete resolution of their presenting symptoms and required no further intervention at a median follow-up of 2 years (IQR 1–2). Four patients (22%) had persistent symptoms postoperatively and were found to have residual surgical material on follow-up cystoscopy requiring retreatment. Median time to retreatment was 7.5 months (IQR 5–12). Three had improvement or resolution of their symptoms after retreatment. Seven of the patients developed worsening SUI after laser ablation, and only one patient developed de novo stress incontinence. However, only four patients chose to pursue further stress incontinence surgery (one periurethral bulking procedure, one colposuspension, and two autologous fascial pubovaginal slings). Four other patients had mild recurrent SUI and were not bothered enough to want another procedure, (including the one women with de novo incontinence). Other treatment-related complications of Ho:YAG ablation included two postoperative UTIs and a small asymptomatic urethral diverticulum seen on a follow-up cystoscopy. Cystoscopy after the final laser ablation showed only a small residual amount of mesh erosion in one patient, which has remained stable and asymptomatic with follow-up.
Systematic review
Our initial literature search strategy identified 230 potential articles after duplicates were removed, and of these, 37 articles were suitable for full-text review (Fig. 1). All articles identified were retrospective case reports (of one or two patients, n = 21) or case series (n > 2 patients, n = 16); there were no randomized control trials (Table 2 and Supplementary Table S1). Weaknesses with all articles identified include small patient numbers, retrospective analysis, and no higher level study designs. Most were single-surgeon and single-center reports. There were no strict inclusion or exclusion criteria reported. A total of 158 patients from case series were included in our evidence synthesis. 5,7,8 –21 Of those, 55 patients were treated exclusively with Ho:YAG. There were several cases that included Ho:YAG as a combination treatment with either transvaginal or other instrumentation due to difficulty with access and complete removal. 22 –25

Systematic search strategy.
Case series of at least three patients are included here; case reports are included in Supplementary Table S1.
MIS = minimally invasive surgery; TOT = transobturator tape; TUR = transurethral resection; UUI = urgency urinary incontinence.
The majority of mesh/suture erosions in these articles were from MUSs (Table 3). The most common site was the bladder, 121/158 (78%) with erosion in both bladder and urethra presenting <2% of the time. Common presenting symptoms were rUTIs, SUI, and LUTS. Reported complications included vesicovaginal fistula (in 2% of patients), postoperative voiding symptoms, pain, worsening or de novo SUI, and urgency incontinence. Repeated procedures were required in 26/158 (16%) of patients. SUI was the main complication and occurred in 32/158 (20%) of patients. Of those with SUI, 24 (75%) patients required further treatment for their postoperative SUI. It was difficult to distinguish which patients developed de novo SUI after mesh excision or had preexisting/worsening SUI. Multiple endoscopic treatments for eroded mesh seemed to be associated with higher SUI (50% in our series and 75% in the literature review).
Only case series with >2 patients were included.
Discussion
Given the popularity of MUS procedures, urologists are likely to encounter foreign body complications. Erosion of surgical material after incontinence surgery can present with a variety of symptoms, including hematuria, LUTS, pelvic pain, or rUTIs. 3,4,26 Clinical evaluation should include a careful history, including prior surgical intervention and determining if synthetic mesh or permanent suture was used. If available, the original operative notes should be obtained. Physical examination should include a speculum examination to identify any vaginal mucosal erosion or fistula. Cystoscopy is used to make the diagnosis of foreign body in the lower urinary tract and is essential for surgical planning. Due to the difficulty in visualizing the female urethra with traditional rigid cystoscopy, flexible cystoscopy is preferable. The location and degree of mesh erosion should be noted along with the presence of any stone material or encrustation. In the setting of prior mesh placement or incontinence procedure, bladder stones, (especially when adherent to the mucosa) should raise suspicion for mesh or suture erosion, which may be associated with a minimal amount of exposed synthetic material. 16,27,28 When adherent stones are present, they should be released with the laser before ablation of the underling mesh or suture material to optimize visualization.
The minimal morbidity of endoscopic erosion treatment has been described before in the literature. 7 Traditional mesh removal with open resection has theoretically higher risks of fistula formation, stricture, and SUI. 3,4 Case series of transvaginal mesh removal suggest a 20%–30% risk of incontinence, and that ∼1/3 women have a second related operation over medium-term follow-up. 29,30 However, we feel that the technical aspects of transvaginal mesh removal are more challenging, and an endoscopic approach is likely more comfortable for urologists who do not do much transvaginal surgery. Appropriate selection of patients for both open and minimally invasive endoscopic approaches can minimize complications. From our experience, the optimal patients for endoscopic treatment have a relatively free floating piece of mesh. It is difficult to treat submucosal mesh, or mesh following the contour of the urethra or bladder using endoscopic techniques.
Several adjunct maneuvers should be considered to help provide maximal removal of mesh. For intravesical mesh or foreign body, a suprapubic tract can be quite helpful when treating erosions near the bladder neck, and this can be accomplished with a suprapubic catheter kit or a 5 mm laparoscopic trocar. Several tricks for retraction of eroded mesh in the urethra have been described 22 –25,31,32 : endoscopic forceps alongside or through the cystoscope, passage of mosquito forceps through the urethra with the use of a pediatric rigid cystoscope for laser fiber control, use of a pediatric nasal speculum in the urethra to position external clamps or scissors with cystoscopic guidance, and the use of a 5F ureteral catheter to stabilize the laser fiber for more controlled fiber placement. We also describe the novel technique of passing a Prolene suture through the urethral mesh (using a cystoscope with a ureteral catheter through the working channel as a guide) and then retrieving the end with a stent grasper and bringing it out through the urethra. This allows for transurethral retraction alongside a rigid cystoscope without hindering the movement of the cystoscope, occupying the working channel, or restricting the direction of the countertraction. Finally, it is necessary to use the laser to resect deep into the tissue to maximize the chance that mucosa will heal over the defect, and we feel that postoperative catheter drainage (to encourage re-epithelialization by collapsing the bladder away from any residual suture or mesh material) and antibiotics help promote tissue healing. In our series, 10/18 (56%) women had visible encrustation, and this was commonly observed in other studies as well. 18
A comprehensive literature review identified 37 relevant articles, summarized in Table 2 and Supplementary Table S1. Ours is the largest case series to date using exclusively Ho:YAG laser for treatment of mesh or suture complications. Both Davis et al. and Ogle et al. had sizeable case series that included the use of Ho:YAG and also demonstrated good outcomes. 18,20 Complications in the identified literature were minimal and comparable to other treatments. The range of retreatment procedures ranged from 10% to 50%, in keeping with our case series finding of 24%. The most common complications were recurrent/persistent SUI and various degrees of voiding dysfunction. In addition to the use of the Ho:YAG laser, other endoscopic approaches included the use of a thulium laser, electrode loop excision, endoscopic scissors, or a combination of endoscopic and open approaches.
Among the patients we treated, there was a varied presentation of the mesh or suture erosion, and a large range of time intervals from the initial incontinence surgery. Our experience confirmed good success rates (94%) and the low morbidity associated with Ho:YAG laser for this problem. Four patients required retreatment, mainly at the start of our series, which may be attributable to our learning curve. No urethrovaginal or vesicovaginal fistula were seen in our series. It was difficult to determine whether SUI was de novo or pre-existing in the published literature. We only had one patient with de novo SUI that did not require surgical treatment. Voiding dysfunction was also not prevalent postoperatively in our cohort, although it has been seen in other series. 11,12 This may be related to residual mesh or chronic detrusor changes as a result of long-standing mesh erosion.
Limitations of our study include the retrospective study design and the relatively small number of patients. The systematic review only identified small case series or case reports, which have all the inherent limitations of reporting bias, short follow-up, and potential lack of generalizability.
Conclusion
Holmium:YAG laser ablation is an effective and minimally invasive option for management of surgical mesh or suture erosion in selected patients. Treatment-associated morbidity was minimal in our series, although repeated endoscopic treatment may be required and recurrent/worsening stress incontinence may occur. The data synthesis from the systematic review was consistent with our case series and represents the best available evidence for discussing the probability of complications after this endoscopic procedure.
Footnotes
Author Disclosure Statement
No competing financial interests exist.
Abbreviations Used
References
Supplementary Material
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