The Current Urology Reports Journal published in June 2012 a review article that describes the different methods used to repair defects in the central and apical compartments utilizing synthetic meshes. The article also presents FDA’s (U.S. Food and Drug Administration) concerns and recommendations with respect to the use of meshes in these procedures. The present article summarizes the information published in the review.
Pelvic Organ prolapse (POP) is a common condition that affects women, and its incidence increases with age. Weakened or damaged pelvic tissues predispose patients of POP surgical repair to high recurrence rates. Surgical failures led surgeons to seek more durable repairs. Therefore, synthetic meshes were used having this objective in mind, as they had been proved to be durable in the correction of abdominal wall hernias.
Meshes can be classified according to type (absorbable or not), pore size (macro or microporous) or filament type (mono or multifilament), the most desirable mesh being a monofilament, macroporous polypropylene mesh. Meshes can be used to improve abdominal and transvaginal POP repairs; and can complete a single or multi-compartment repair. They were also proposed to be less invasive and their placement techniques more standardized. Placement techniques include self-fashioned patches and tension free vaginal kits, and the kits can be trocar, anchor or suture based. The first kits designed to treat apical compartment involved the delivery of the mesh arm using trocars (sharp-edge instruments used inside a cylinder to introduce it into a cavity), passed through the obturator membrane (membrane that closes the “hole” in the pelvis), these kits include Gynecare, Anterior Prolift®, Perigree® and Avaulta®. Subsequently, single-incision kits that use a needle driver device or self-fixating tips instead of trocars were developed, including Pinnacle®, Uphold® and Elevate® systems. Procima® is a more recently developed system and is a single-incision, fixation-less system, held in place for three weeks by a pessary-like (similar to the outer ring of a diaphragm) vaginal support device (VSD), sewn into place at the time of surgery. Mesh patches can also be used for single or multi-compartment repairs and there are also different approaches that can be used for these procedures.
Abdominal sacrocolpopexy (ASC) is considered to be the gold standard for apical vaginal compartment repair; some surgeons have developed variations in this technique to address defects in the anterior and posterior compartments at the time of ASC. Three different approaches may be taken when performing an ASC: open, laparoscopic or robotic surgery. Independent of the approach taken, the ASC technique remains mostly unchanged: use of permanent mesh, secure fixation of graft to the sacral promontory and the vaginal cuff and the complete reduction of enteroceles (protrusions of the small intestines and peritoneum into the vagina) with culdoplasty (sutured material drown towards midline, helping close peritoneal surface) which reduces chances of recurrence. ASC was traditionally ideal for younger, sexually active patients. Although the development of minimally invasive procedures (e.g. laparoscopic), which result in decreased blood loss and shorter hospital stay, made SAC also suitable to elderly patients.
ASC procedures can convey intraoperative and postoperative complications. A study based on 1,500 patients identified that reoperation due to mesh complications occurred more frequently after transvaginal mesh placement into the anterior compartment; mesh exposure being the most common complication. Risks factors for mesh exposure include smoking, young patient age, sexual activity and total mesh placement.
In 2008, the FDA released a public health notification about complications associated with the use of transvaginal mesh for POP repairs. After that notification, the complications were reported with increased frequency. Consequently, the FDA updated the health warning in 2011, stating that the complications were not as rare as previously reported and that it was not clear whether mesh repairs are more effective than non-mesh repairs. A FDA advisory panel recommended clinical studies for pre-market evaluation, as well as post-market studies or surveillance. Furthermore, the mesh kits, which had been regulated as Class II, were classified as Class III. Manufacturers of Class II devices only have to demonstrate that new devices are equivalent to an already approved, similar Class II device. FDA also requested that manufacturers submit study designs that demonstrate mesh procedures not to be inferior to native tissue repairs. Meshes used for ASC have been excluded from this requirement, as are considered well established and having strong clinical data that supports their efficacy and safety. High quality data is needed to be able to answer the questions regarding outcome and complications of the use of mesh in POP repairs. Mesh supporters report that a large number of procedures are performed safely and efficiently. They also raised the concern on available data to compare mesh and non-mesh procedures, as tissue-related complications are not entered into a device database, therefore making it difficult to perform comparisons. Moreover, they advocate that most complications are a result of technical deficiencies and that the complication numbers may decrease with skilled surgeons. This statement is supported by the authors with data from two different studies; the authors also emphasize that training on mesh placement should be more robust.
References
Central Compartment and Apical Defect Repair Using Synthetic Mesh. Karen Soules; J Christian Winters and Christopher J. Chermansky. Current Urology Reports. 2012. 13:222-230