- At this time, the traditional anterior colporrhaphy with attention to apical suspension remains the gold standard.
- If only some defects of the anterior wall are addressed at the time of reconstructive surgery, failure may be more likely.
- Women with grade 3 or 4 cystoceles often have evidence of bladder outlet obstruction on urodynamic testing.
- In 52% of cases, cystoceles coexist with detrusor instability and evidence of impaired detrusor contractility.
- A thorough preoperative evaluation includes assessing the apex, having the patient strain to maximize the defect, looking for paravaginal detachments, and making every effort to “unmask” occult stress urinary incontinence.
Ask a pelvic reconstructive surgeon to name the most difficult challenge, and the answer is likely to be anterior vaginal wall prolapse. The reason: The anterior wall usually is the leading edge of prolapse and the most common site of relaxation or failure following reconstructive surgery. This appears to hold true regardless of surgical route or technique.
Short-term success rates of anterior wall repairs appear promising, but long-term outcomes are not as encouraging. Success usually is claimed as long as the anterior wall is kept above the hymen, since the patient rarely reports symptoms in these cases.
Another challenge involves the use of allografts or xenografts, which have not undergone sufficient study to determine their long-term benefit or risks in comparison with traditional repairs.
This article reviews anatomy of the anterior vaginal wall and its supports, as well as surgical technique and outcomes.
Why the anterior wall is more susceptible to prolapse
One theory is that, in comparison with the posterior compartment, the anterior wall is not as well supported by the levator plate, which counters the effects of gravity and abdominal pressure. Normally, the anterior wall rests horizontally on the posterior wall, which in turn rests on the levator plate. When the levator muscles weaken, the anterior wall is the first to fall as increasing force is placed on the connective tissue supports.
Other possibilities: The anterior compartment’s attachments to the pelvic sidewall or apex may be weaker, the anterior wall may be more elastic or less dense than the posterior wall, and the anterior wall may be more susceptible to damage during childbirth or to the effects of age and loss of estrogen.
If only some defects are addressed at surgery, failure may be more likely. Some experts believe pelvic surgeons have focused too much attention on the urethrovesical junction in patients with concomitant urinary incontinence and not enough attention on suspending the anterior wall at the apex.
For most women, it is probably a combination of many of these factors that renders the anterior compartment so vulnerable.
Anatomy of the pelvic floor
The anterior vaginal wall resembles a trapezoidal plane due to ventral and more medial attachments near the pubic symphysis, and dorsal and more lateral attachments near the ischial spine (FIGURE 1).1 This helps explain the many appearances of the cystocele. The type of cystocele is defined by the location of the break in the fascial attachments.
Paravaginal defects. The trapezoidal anterior wall is suspended on both sides from the parietal fascia overlying the levator ani muscles at the arcus tendineus fascia pelvis (ATFP). Prolapse can occur when there is loss of attachment to the pelvic sidewall at any point between the pubis and ischial spine.
First described by White2 and characterized later by Richardson et al,3 this loss of lateral attachment is called a paravaginal defect or displacement cystocele (FIGURE 2). The goal of paravaginal repair is to reattach the lateral vaginal walls to the ATFP, either abdominally, laparoscopically, or vaginally.
Central defects, the rarest type of anterior wall prolapse, involve a loss of support near the pubis and tend to be smaller. The most common manifestation is urethral hypermobility.
Transverse defects occur when the top of the pubocervical fascia detaches from the cervix or vaginal apex, both of which are suspended from the uterosacral-cardinal ligament complex. A transverse cystocele is evidenced by loss of the anterior fornix. The anterior wall appears to be attenuated in the midline, and the vaginal mucosa is pale, thin, and smooth (FIGURE 3).
Goals of traditional repair. The traditional anterior colporrhaphy aims to excise or reinforce the attenuated transverse defect with plication of the “endopelvic fascia” in the midline of the anterior vaginal wall. The endopelvic fascia is not true fascia but the muscularis of the vaginal wall. It is comprised of smooth muscle and elastin along with the collagenous adventitia layer.4
The importance of restoring apical wall support becomes apparent when one considers the trapezoidal anatomy. The most common sites of defects or detachments of the anterior wall are near the ischial spines laterally. In an operative case series of paravaginal defects, DeLancey1 found the site of defect to be near the ischial spine in 96% of cases. The reattachment of the apex near the level of the spine becomes the highest point of support for the anterior vaginal wall.