Surgery for Pelvic Organ Prolapse in 2014

Approximately 3% of women in the community have symptoms of prolapse^{1, 2, 3} with the prevalence peaking in the seventh decade. Surgery for pelvic organ prolapse (POP) is performed at a rate of 1.5–1.8 per 1000 women years,^{4, 5} which translates to 7% of American women undergoing prolapse surgery during their lifetime.^{6, 7} The rate of prolapse surgery is even higher amongst American women with private health insurance, with 12.6% of women having undergone surgery by 80 years of age.⁸ In a single report from Western Australia, the authors demonstrated the lifetime risk of prolapse surgery was as high as 19%.⁹ Wide variation in data may be attributed to a variety of factors including age-related changes in the community or variation in accuracy of data capture, and demonstrates a need for further epidemiological research. Owing to the aging population where women older than 80 years of age are the fastest growing demographic in the USA, many have predicted that surgical intervention for POP will increase.¹⁰ However, in the past decade, the rate of interventions has remained static, ^{11, 12, 13} perhaps reflecting other changing demographics in the community such as decreasing parity.

There are currently no evidence-based guidelines to advise clinicians and women as to which surgical intervention is most appropriate. The aim of this chapter is to provide an overview of the current status of literature in relation to the surgical management of prolapse.

Prolapse in the anterior compartment of the vagina (cystocele and urethrocele) is the commonest site of prolapse in the vagina and remains a challenge for the reconstructive gynecologist. Anterior colporrhaphy remains the most common surgical procedure in the management of anterior compartment prolapse and the success rate in retrospective series ranges from 80 to 100%.^{14, 15, 16} However, under more recent and rigorous evaluation of randomized controlled trials, the success rate on examination was reported to be only 30–57%.^{17, 18} The reader should be aware that despite this seemingly low objective success rate, especially in the Weber paper¹⁸ the reoperation rate was less than 1% after 23 months.

Following the successful use of grafts in the management of hernias and suburethral slings in the management of stress urinary incontinence, since 2002 clinicians have been utilizing grafts (synthetic mesh and biological material) in the repair of anterior compartment prolapse. Unfortunately, now over a decade later the benefits derived from incorporating grafts into anterior compartment prolapse surgery are not what were envisaged. In our 2013 Cochrane meta-analysis¹⁹ that compared evidence from 10 randomized controlled trials, it was demonstrated that transvaginal polypropylene mesh decreased both subjective awareness of prolapse (RR 1.62, 95% CI 1.22) and objective evidence of prolapse on examination (RR 3.50, 95% CI 2.71–4.52) compared with traditional anterior colporrhaphy (AC). However, the transvaginal mesh kits were also associated with a longer operating time, greater blood loss, and greater subsequent prolapse in the apical and/or posterior compartment prolapse. The risk of mesh erosion was 11.6% and the rate of reoperation to correct mesh exposure was 6.8%. The total reoperation rate was 10% after transvaginal mesh in the anterior compartment as compared to 5% after AC. Many of the transvaginal mesh kits for the management of anterior compartment prolapse have subsequently been removed from the market.

Currently, two newer single incision mesh kits are available using lightweight mesh (24 g/m²) with no arms traversing the obturator space and the tail secured to the sacrospinous ligament for apical support. Moore et al.²⁰ reported a 92% objective success rate at 13 months in 60 patients with anterior and or apical prolapse undergoing Anterior Elevate (American Medical Systems, Minnetonka, MN, USA). No mesh exposures were reported and the authors who reviewed the patients reported a financial relationship with the company manufacturing the product being evaluated.

Vu et al.²¹ conducted a retrospective evaluation of a new reduced size transvaginal polypropylene mesh product, “Uphold” (Boston Scientific, Marlborough, MA USA), with only apical fixation in 115 patients with a mean review of 12 months. The success rate was high at 98% on examination and the mesh exposure rate was low at 2.8%. One of the authors was the patent holder for the product being evaluated. Further rigorous evaluation of these products is required.

Biological grafts have also been utilized in the surgical management of anterior compartment prolapse. Porcine dermis, in a single randomized control trial, demonstrated an advantage over AC.²² This advantage was not demonstrated in other smaller trials.^{23, 24} Feldner et al.²⁵ compared anterior colporrhaphy with 7 x 10 cm small intestine submucosa (SIS) graft in a randomized controlled trial and demonstrated the objective failure rate was significantly higher after the AC 33% (9/27) compared with the SIS group 14% (4/29). The dyspareunia rate was similar in both groups and no reoperations were reported.

Finally, little information is available on the surgical management of recurrent anterior compartment prolapse and many authors suggest this may be a suitable indication for transvaginal mesh. Unfortunately, there are no data in the literature to support this claim. Fayyad et al. prospectively evaluated 36 women with recurrent anterior compartment prolapse and reported an objective success rate (less than stage 2 anterior compartment prolapse) of 47% with a high mesh exposure rate of 19%.²⁶ In a prospective multicenter Dutch randomized controlled trial, women who had undergone prior prolapse surgery were randomized between native tissue repairs and tension free vaginal polypropylene mesh.²⁷ Allocation concealment was not confirmed and neither patient, surgeon nor the assessor were blinded. The surgeons performed the reviews and all authors declared a financial relationship with the company manufacturing the commercial mesh product. Unfortunately, preoperatively the two groups were significantly different pointing to a systematic failure in the randomization process which discredits the findings of the manuscript.

Table 1 Summary of surgery for anterior compartment prolapse

SIS, small intestine mucosa; AC, anterior colporrhaphy

The traditional posterior colporrhaphy plicates the rectovaginal fascia between the rectum and the vagina and is performed for bulging of the small bowel (enterocele), rectum (rectocele) or perineum into the vagina. The prevalence of rectocele in women ranges from 12.9 to 18.6% and the average annual incidence is estimated to be 5.7 cases per 100 women years.^{14, 15} Approximately 225,000 operations are performed every year in the US for POP and repair of posterior vaginal wall is performed at a variable rate of 40–85%.^{4, 7, 16}

The mean reported anatomic success rate with this type of repair is 83% (range 76–96%) with mean postoperative dyspareunia rate of 18% ( range 5–45%) and 26% using vaginal digitation to defecate.¹⁷ Plication of the levator ani muscles during this surgery is associated with a durable repair. However, due to the high rate of dyspareunia,^{17, 18} levatorplasty is discouraged. A site specific repair was popularized in the 1990s that involved the repair of individual defects in the fascia. Meta-analysis by Karram demonstrated that this approach has similar outcomes to the traditional fascia plication with the mean reported anatomic success rate of 83% (range 76–96%) with postoperative dyspareunia rate of 18% (range 5–45%) and 26% using vaginal digitation to defecate.¹⁷ When the two techniques were compared, Abramov¹⁹ reported a significantly higher recurrence rate of rectoceles following the discrete site-specific repair, 32% as compared to 13% following the midline fascial plication (p = 0.015). The correction of the rectovaginal fascia defect that allows entrapment of faeces on straining in significant rectoceles may be too large to be repaired with the discrete approach²² and appears to be corrected by the more robust midline fascial plication.

The traditional fascia repair has been compared to repair with porcine small intestine submucosa (SIS) and meta-analysis in the Maher 2013 Cochrane review²³ demonstrated the failure rate on examination to be twice as high following the SIS repair (20%) as compared to following the fascial repair (10%) without any difference in dyspareunia rate between the two groups.^{22, 24} 

The transvaginal approach has also been compared to the transanal approach for the management of posterior compartment defects in three randomized controlled trials. The 2013 Cochrane review concluded that the awareness of prolapse and prolapse on examination was significantly lower with the transvaginal approach as compared to transanal approach.²³ A further single randomized controlled trial that was not able to be included in the Cochrane meta-analysis, demonstrated that transvaginal repair had superior outcomes on defecography and lower rates of obstructed defecation as compared to transanal repair.

MODIFIED SACRAL COLPOPEXY

The abdominal route has been employed in the correction of posterior vaginal wall prolapse when a co-existing apical defect requires surgery. The technique is a modification of sacrocolpopexy with extension of the posterior mesh down to the distal posterior vaginal wall and/or the perineal body. Early results in case series have been promising,^{26, 27, 28, 29} however, further evaluation is required.

Table 2 Summary of surgery for posterior compartment prolapse

Prolapse of the apical compartment includes both uterine and vault (post-hysterectomy) prolapse. In a recent analysis of a national dataset from the USA, Eilber et al.³⁰ reviewed 2756 women who underwent an anterior colporrhaphy, posterior colporrhaphy, or both, with or without apical suspension in 1999. They then analysed those that underwent further surgical intervention over the next decade. They demonstrated the importance of adequate apical compartment prolapse support in minimizing prolapse after level 2 repairs of the anterior and posterior compartment alone. They found that the addition of an apical suspending surgery to anterior colporrhaphy (AC) reduced the need for re-operation from 20% to 11.6%. While the addition of the vault suspending procedure to posterior colporrhaphy (PC) alone did not significantly reduce the reoperation rate (14.6 to 12.9%), the repeat PC was significantly higher in those that underwent an isolated posterior repair than it was in the group whose index posterior colporrhaphy was performed with an apical suspension procedure (4.5% compared with 0.4%, respectively; p = 0.01).

Our 2013 Cochrane meta-analysis of randomized controlled trials on apical suspending surgery made the following conclusions. Abdominal sacral colpopexy (ASC) was superior to vaginal-based sacrospinous colpopexy with reduced stage 2 prolapse (RR 0.29, 95% CI 0.09–0.97), recurrent vault prolapse (RR 0.23, 95% CI 0.07–0.77), postoperative stress urinary incontinence (RR 0.55, 95% CI 0.32–0.95) and less postoperative dyspareunia (RR 0.39, 95% CI 0.18–0.86). In contrast, ASC was associated with a longer operating time, longer time to recover and was more expensive than the vaginal-based sacrospinous colpopexy.

In a single study only available in abstract form, the sacral colpopexy was also superior to vaginal uterosacral colpopexy with lower recurrence rate (6% versus 34%) and reoperation rate (5% versus 18%).³¹

In a recent large multicenter randomized controlled trial, Barber et al.³² compared sacrospinous colpopexy (n = 186) to uterosacral colpopexy (n =  188) in women with apical prolapse and stress urinary incontinence. They found that at 2 years the rate of awareness of prolapse, prolapse on examination and reoperation rate for prolapse were similar in both groups. In a separate evaluation of the impact of perioperative behavioral therapy the authors also demonstrated no detectable reduction in urinary symptoms, prolapse symptoms or anatomic findings with the addition of five sessions of perioperative behavioral change and pelvic floor muscle training as compared to no intervention.

To minimize the morbidity associated with open sacral colpopexy many commenced evaluating the efficacy of laparoscopic sacral colpopexy (LSC) as a means of reducing postoperative pain and recovery time. In a single randomized controlled trial, Freeman et al.^{31, 33} demonstrated that the LSC and ASC had similar anatomical outcomes with reduced blood loss, length of stay and morphine use postoperatively after the LSC. We compared the laparoscopic sacral colpopexy (n = 53) to transvaginal mesh (n = 54) in those with vaginal vault prolapse and demonstrated that the LSC had a longer operating time than the transvaginal mesh (97 min versus 55 min).³⁴ However, the LSC had less blood loss, lower cost, quicker return to activities of daily living, higher patient satisfaction, higher anatomical success and a lower reoperation rate at 2 years as compared to transvaginal mesh surgery. The LSC has also been compared to robotic sacral colpopexy (RSC) in two small randomized controlled trials^{35, 36} which both demonstrated that laparoscopic and robotic approaches to sacral colpopexy were equally effective in the short-term in correcting prolapse. However, both also demonstrated the LSC had reduced operating time, postoperative pain and cost as compared to RSC.

Table 3 Summary of surgery for posthysterectomy prolapse

LSC, laparoscopic sacral colpopexy; ASC, abdominal sacral colpopexy; RSC, robotic sacral colpopexy

A variety of controversies still exist surrounding sacral colpopexy. Much of the literature demonstrating superiority of sacral colpopexy as compared to other procedures has been based on posthysterectomy prolapse,^{39, 40, 42, 43} while others studies have included some with uterine prolapse.^{44, 45} The options available including sacral colpopexy in the management of uterine prolapse include hysterectomy with sacral colpopexy, sacral hysteropexy (uterus attached to sacrum with mesh) or sub-total hysterectomy.

Contraindications to uterine preservation include uterine abnormalities, history of current or recent cervical dysplasia, abnormal menstrual or postmenopausal bleeding, BRCA1 or BRCA2 gene mutations, tamoxifen therapy or inability to comply with routine gynecology surveillance.  

Roovers and colleagues³⁷ performed the only randomized controlled trial comparing abdominal sacral hysteropexy (n = 41) to vaginal hysterectomy and uterosacral suspension (n = 41). While both groups reported high success rates for the apical (95%) and posterior (85–95%) compartments, recurrences in the anterior compartment were high in both groups (61% and 64%). There were more doctor visits and reoperations performed or planned in the abdominal hysteropexy group.

Gutman and Maher reviewed the literature on sacral colpopexy and uterine prolapse in 2012 and in meta-analysis found 339 cases of sacral colpopexy with hysterectomy and 129 cases of sacral hysteropexy. While the success rate was over 90% in each group the rate of mesh exposures was more than five times higher after sacral colpopexy and hysterectomy as compared to hysteropexy (8.5% versus 1.5%).⁴⁶ Subtotal hysterectomy is performed to decrease the risk of mesh exposure associated with hysterectomy at sacral colpopexy. However, there is a paucity of data on the efficacy of this approach. Gutman’s meta-analysis found only 58 subtotal hysterectomy cases that reported their outcomes with only one mesh exposure reported (2%). Significant further evaluation is required of the role of sacral colpopexy in those with uterine prolapse.

Uterine preservation surgery can also be performed vaginally with the cervix being suspended to the sacrospinous ligament (sacrospinous hysteropexy). In a single randomized controlled trial comparing sacrospinous hysteropexy (n = 37) to vaginal hysterectomy with uterosacral ligament suspension (n = 34), Dietz et al. reported a higher rate of apical recurrences in the hysteropexy group (21% versus 3%, p = 0.03).⁴⁷ Three women had stage 4 uterine prolapse preoperatively that underwent hysteropexy and all developed recurrent uterine prolapse within 1 year. Subjective outcomes improved for both groups. Hysteropexy was associated with shorter hospitalization, quicker recovery with more rapid return to work and longer total vaginal length (8.8 cm versus 7.3 cm, p <0.01). Both groups had high rates of postoperative anterior vaginal wall prolapse (51% vs. 64%).  

Prior to this, three cohort studies comparing sacrospinous hysteropexy to vaginal hysterectomy with or without sacrospinous fixation showed no difference in anatomical or symptomatic improvement with the exception of a three-fold increase in overactive bladder and urge incontinence symptoms in the vaginal hysterectomy group.^{48, 49, 50}  The sacrospinous hysteropexy group had the advantage of reduced perioperative morbidity, shorter operating time, less blood loss, faster recovery, and fewer complications with similar recurrence and reoperation rates. Again, uterine preservation surgery performed vaginally needs further evaluation.

Table 4 Summary of uterine prolapse surgery

Obliterative surgery, such as total colpocleisis, closes off the vaginal canal and limits the pelvic viscera from prolapsing. Obliterative procedures are less commonly performed in Europe, Asia, and Australia compared with the US, and are usually reserved for women who are elderly, medically compromised and no longer sexually active. Colpocleisis has not been evaluated under the auspices of a randomized controlled trial. However, in large case series, the technique has demonstrated low perioperative morbidity and low risk of recurrent prolapse. The obvious disadvantage is the elimination of the potential for vaginal intercourse. Preoperative counselling is essential when choosing between the obliterative and reconstructive options. A systematic review of colpocleisis published in 2006 noted colpocleisis appears to be nearly 100% effective for correcting pelvic organ prolapse, however, until recently little was known about postoperative functional or quality of life outcomes.³⁸ In the past few years a number of reports evaluating symptom improvement and changes in quality of life after colpocleisis have been reported.^{39, 40, 41, 42} Overall, these series have found high rates of patient satisfaction and significant functional improvement with low rates of regret for loss of sexual function.^{39, 40, 41} In a single retrospective study Murphy et al. compared over 65 year old women undergoing colpocleisis (n = 45) with transvaginal mesh (Prolift, Ethicon Women’s Health and Urology) repair (n = 48) and reported improvements in condition-specific quality of life and postoperative patient satisfaction were comparable between the two treatment groups.⁴³

In a 2-year follow up of English women (n = 23), Bombieri et al.⁴⁴ reported 87% would recommend the surgery to a friend and the rate of bowel and bladder dysfunction on validated pelvic floor questions was low. In the largest series to date, Zebede et al.⁴⁵ reported on 325 women at a mean age of 81 years who underwent colpocleisis over a 10-year period. At a mean follow-up of nearly 12 months, patient satisfaction was high with 93% reporting being cured or significantly improved. The total complication rate was 15% with a 1.3% mortality rate, reminding the reader that the risk associated with operating on the elderly are not insignificant. In general, major complications due to performance of surgery on the elderly (e.g. cardiac, pulmonary and cerebrovascular complications) occur at a rate of approximately 2%.³⁸ Major complications due to the surgery itself (e.g. pyelonephritis, blood transfusion) occur at a rate of approximately 4%.³⁸ One complication that appears to be uniquely associated with obliterative surgery is development de novo rectal prolapse after surgery.^{46, 30} Collins et al. performed a retrospective cohort study of 916 women undergoing vaginal POP surgery and found that the incidence of postoperative full-thickness rectal prolapse in women who were aged 65 years old or more who underwent obliterative surgery was three of 74 (4.1%), with an estimated odds ratio of 22 (95% CI, 2.3–196; p <0.002) compared with women who were aged 65 years old or more who underwent reconstructive surgery.⁴⁶

Table 5 Summary of obliterative vaginal surgery

The lifetime risk of a woman undergoing prolapse surgery has been reported to vary between 7 and 19% and requires further evaluation. While the demand for prolapse surgery is expected to increase in the future as our population ages, the effect of reduced parity and increased elective cesarean section has not been fully evaluated. During the past decade a wide variety of biological and synthetic grafts have been introduced to improve the outcomes associated with native tissue prolapse surgery. These innovations, especially in the difficult to manage anterior compartment prolapse, showed promise with reduced symptoms of prolapse and prolapse on examination. Unfortunately, unforeseen outcomes such as mesh exposure and pain related to contraction of the mesh resulted in the poor patient outcomes and the removal of some mesh products from the market. Stricter governance related to the introduction of new devices related to prolapse and continence surgery is now in place in the USA and will appropriately reduce the likelihood of newer products with unforeseen problems being released onto the market. Hopefully, future research into graft materials for POP surgery that are able to offer support and strength while retaining distensiblity will not be hindered as a result of new device and product regulation.