Definition

Uterovaginal prolapse is defined as descent of a pelvic organ or structure into and sometimes outside the vagina. ‘Prolapse’ can be taken as meaning pelvic organ prolapse, urogenital prolapse, genital prolapse, rectocele/cystocele/urethrocystocele, vaginal vault prolapse and uterine descent (Fig. 8.1).

Figure 8.1 Areas of potential prolapse. (1) Urethrocele; (2) cystocele; (3) apical (uterus/vault); (4) enterocele; (5) rectocele.

Incidence

The incidence of prolapse in the female population is difficult to define as many women do not seek medical attention and clinical examination does not necessarily correlate with symptoms. It is estimated that a woman has an 11% lifetime risk of having an operation for prolapse by the age of 80 and that 30% of these patients will require further prolapse surgery.

Anatomy of the pelvic floor

Prolapse is caused by a failure of the supporting structures of the genital tract and it is, therefore, important to have an understanding of this anatomy. The pelvic floor consists of muscular and fascial structures that support the abdominopelvic cavity and the external openings of the vagina, urethra and rectum. The uterus and vagina are suspended from the pelvic side walls by endopelvic fascial attachments that support the vagina at three levels or anatomical sections:

Most of the endopelvic fascia fibres attach to the vaginal wall, but a few pass from one side to the other and are recognized as the rectovaginal septum separating the vagina and rectum. Damage at the different levels of vaginal support causes different types of prolapse. Level 1 support failure results in vaginal vault or uterine prolapse, whereas loss of level 2 support leads to development of cystocele and rectocele, and level 3 disruption results in any of the above (as it acts as an anchor for all the supports) and a deficient perineum.

Types of prolapse

Anterior vaginal wall prolapse may have bladder or urethra above it and this is known as a cystocele, urethrocele or a combination of the two. Posterior wall prolapse can contain a part of the rectum (rectocele) or higher up on the posterior wall when the pouch of Douglas containing small bowel can herniate through the posterior fornix (enterocele). An enterocele is usually associated with uterine prolapse, but is also known to be a late complication of previous colposuspension procedures.

Uterine prolapse is descent of the cervix and uterine body into the vagina and three types are recognized:

Vault prolapse is eversion of the vault of the vagina that can occur after hysterectomy.

Aetiology of prolapse

Clinical assessment

Prolapse is often asymptomatic, but patients may complain of any or a combination of the symptoms outlined below.

There may be a dragging sensation in the pelvis or a feeling of ‘something coming down’ through the vagina. Patients may feel a swelling at the vagina that gets worse as the day progresses and describe difficulty with intercourse (dyspareunia).

Anterior wall prolapse can be associated with urinary symptoms, in particular leakage of urine with increased intra-abdominal pressure, e.g. on coughing or sneezing, or incomplete emptying of the bladder resulting in high residual volumes of urine that may lead to urinary tract infections. Patients may also complain of frequency, nocturia or urgency with or without incontinence, which could be due to cystitis or because of a coexisting overactive bladder.

Posterior wall prolapse may be associated with difficulty in defecation to the extent that many patients may need to attempt digital reduction of the prolapse to ease defecation. Procidentia may result in vaginal bleeding or discharge, as an erosion or decubitus ulcer may form on the exposed prolapsed uterus. Rarely, procidentia may result in ureteric obstruction causing chronic renal failure.

History

Ascertaining the degree of impairment of quality of life or daily activities will influence management. Specific questioning on urinary and bowel function as well as sexual function should be included. A full obstetric and gynaecological history as well as medical and surgical history will guide the practitioner as to the suitability of conservative or surgical management options. Specific instruments, for example, the King’s Health Questionnaire, are available and are routinely used to measure quality of life.

Examination

Abdominal examination should always be performed to exclude any masses or organomegaly. The woman should first be examined in the dorsal position when she is asked to bear down, strain or cough, during which inspection of the introitus should reveal any obvious second- or third-degree prolapse; stress incontinence may be demonstrated and atrophy may be apparent. Examination is then performed with the patient in the Sims’ position (patient in left lateral position with chest at 45°∞ to the examining couch, the left leg straight, the right hip extended and knee flexed) with a Sims’ speculum, which allows full inspection of the uterine prolapse and vaginal walls (Fig. 8.2). The blade of the Sims’ speculum is inserted along the posterior wall of the vagina and retracted in order to display the anterior wall, with the patient bearing down. The anterior wall can be supported with sponge forceps to assess for apical descent (cervix or vault) and then the anterior vaginal wall is supported in order to assess the posterior wall, with the patient bearing down. Vaginal examination is performed in the usual manner with assessment of the uterus and adnexae as previously outlized and any obvious descent of the cervix or prolapse of the vaginal walls noted. In the research setting and increasingly in specialist centres, a system called pelvic organ prolapse quantification (POPQ) can be utilized. This is a complex nine-point assessment of uterovaginal prolapse, which describes four stages of pelvic organ descent relative to the hymenal ring.

Figure 8.2 Patient in left lateral position for use of Sims’ speculum.

Urodynamics

Subtracted cystometry and flow studies should always be considered in women with genital prolapse and urinary symptoms before offering surgery. Stress urinary incontinence can be masked by prolapse and these patients may also have chronic voiding dysfunction.

Treatment

The choice of treatment depends on the patient’s wishes, general health and desires regarding future sexual function. Conservative or surgical options are available and a combination of the two is ideal. Management will depend on the severity of symptoms and suitability for anaesthesia.

Conservative measures

Many types of pessaries have been developed for vaginal and uterine support, although surgical correction should be considered whenever possible. A typical plastic ring pessary should comfortably rest between the posterior fornix and the symphysis pubis, thereby supporting and stretching the vaginal wall, preventing vault prolapse and directly supporting any cystocele present (Fig. 8.3). Pessaries need to be replaced 6-monthly to avoid infection or ulceration of the vagina. Pelvic floor re-education or strengthening is best achieved under the direction of a trained continence advisor or by a physiotherapist using directed muscle exercises or weighted vaginal cones that the woman must try to retain within the vagina. Sometimes this can be combined with electrical stimulation of the pelvic floor muscles, which has also been shown to be of benefit.

Figure 8.3 Placement of vaginal ring pessary for first- and second-degree uterovaginal prolapse.

Surgical procedures

The choice of procedure depends on the patient and the type of prolapse that exists – the ‘site-specific’ repair. Factors that influence the type of surgical procedure include fitness of the patient and suitability for anaesthesia, whether the patient is sexually active and the surgeon’s preference.

Anterior repair (colporrhaphy) is a procedure that repairs fascial defects in the anterior vaginal wall and removes the excess vaginal skin that results from the prolapse (Fig. 8.4). This can also include the use of a supporting suture (buttress) under the urethra. Complications are uncommon, although postoperative voiding difficulties may occur and recurrence of prolapse occurs in up to 50% of patients.

Figure 8.4 Anterior repair/colporrhaphy.

Posterior colpoperineorrhaphy is a repair of the posterior wall prolapse, which involves repair of rectovaginal fascial defect and approximation of the levator ani muscles medially to support the rectum with removal of the excess vaginal skin (Fig. 8.5).

Figure 8.5 Posterior repair/colporrhaphy.

Vaginal hysterectomy can be performed with the above procedures in cases where there is significant uterine descent, especially if the patient is postmenopausal or if there are significant menstrual problems.

To preserve the uterus, e.g. for women who may still wish to become pregnant, it is possible to combine the anterior and posterior colpoperineorrhaphy with partial amputation of the cervix (which is often elongated in prolapse) and approximation of the transverse cervical ligaments in the midline for support. This is called a Manchester (or Fothergill) repair.

Sacrohysteropexy is another procedure that can be performed if the patient wishes to preserve her uterus. It is an abdominal procedure that involves using a synthetic mesh placed between the cervix and the sacrum to support the uterus and this is increasingly being performed laparoscopically or robotically.

Vault prolapse can be corrected via either an abdominal (sacrocolpopexy) (Fig. 8.6) or vaginal (sacrospinous ligament fixation) procedure. The latter involves suturing the vault to the sacrospinous ligament. Both these techniques are effective, but the vaginal route has less immediate postoperative morbidity. Both techniques of vault fixation can cause either posterior or anterior (respectively) wall prolapse in the long term.

Figure 8.6 Abdominal sacrocolpopexy – fixation of the prolapsed vault using mesh attached to the sacral promontory.

It is worth noting that some anti-incontinence procedures, in particular a Burch colposuspension (Fig. 8.7), may also cure a cystocele, especially if done in conjunction with a paravaginal repair.

Figure 8.7 Burch colposuspension.

Physiology of micturition

The main function of the bladder is to convert the steady stream of urine produced by the kidney into a convenient intermittent process of evacuation. Therefore, the bladder must first act as a reservoir and, second, as an intermittent voluntary excretory organ that acts within socially acceptable restraints to allow voiding. This requires a complex neurological network, which coordinates sensory afferent input and motor efferent output in a reciprocal fashion.

Bladder innervation

Normal bladder function requires coordinated detrusor relaxation and urethral sphincter contraction during its filling phase and the converse during micturition. The detrusor muscle is innervated by parasympathetic cholinergic fibres derived from S2–4. These nerves are targeted by the anticholinergic medications to inhibit unstable detrusor contractions. It also has some sympathetic supply from the thoracic and lumbar segments T10–L2. Connections of the lower urinary tract to the central nervous system are extraordinarily complex and many discrete centres with influences on micturition have been identified.

Involuntary leakage of urine can only occur if the intravesical pressure exceeds the urethral closure pressure. Urethral sphincter contraction and detrusor relaxation are achieved by different mechanisms and so no simple drug effectively achieves both.

Assessment

Investigation of urinary incontinence

Patients should be given a fluid chart or micturition diary to complete a week prior to the consultation so that a clear pattern of fluid intake and voiding can be established. At the same time a quality-of-life questionnaire can be completed to assess the extent of impact of symptoms on the patient’s daily activities. This will provide a baseline against which the effects of treatment may be assessed.

Measurement of urinary flow rate can be performed on the patient who attends with a full bladder. This is performed with an intravesical pressure catheter, which can measure bladder pressures during voluntary voiding into a special commode that can measure the flow rate. This will differentiate poor flow as a result of an obstructed urethra as opposed to a poorly functioning detrusor muscle. While inserting the catheter, a specimen of urine can be collected to exclude urinary infection.

Subtracted cystometry is a urodynamic test that measures the intravesical pressure during artificial filling of the bladder and then during voiding. This can then determine the presence or absence of involuntary detrusor contractions and, therefore, diagnose detrusor instability if present.

Videocystourethrography is a test that can be performed at the same time as cystometry, using a radiopaque fluid as the filling medium. X-ray imaging of the full bladder can be performed to assess for ureteric reflux, bladder diverticulum, bladder descent or urinary leakage whilst the patient coughs. This is also a useful test if a vesicovaginal fistula is suspected.

Management

Establishing an accurate diagnosis of the cause of urinary symptoms is important and requires invasive urodynamic investigation. However, treatment can be instigated prior to urodynamic assessment provided there is no contraindication and in the absence of the following: urinary tract infection, haematuria, neuropathy, uropathology, voiding difficulty, previous surgery or if uncertainty of the cause of the urinary symptoms exists. In these situations referral for further investigation is mandatory.

Women with mild overactive bladder symptoms may only require reassurance or advice on conservative measures such as reducing fluid intake, abstinence from caffeine drinks and alcohol, change of voiding habits, and alteration of medications, e.g. diuretics. However, the mainstay of treatment is drug therapy (anticholinergics) and bladder retraining or bladder drill:

The main purpose of drug therapy is to overcome the initial overactive bladder symptoms so that simple measures like bladder retraining have a greater impact in the long term. If symptoms are completely unresponsive to conservative and medical treatments, surgery can be offered. Sacral nerve implants for neuromodulation and intravesical Botox therapy have been shown to be effective in patients with intractable overactive bladder symptoms.

Aetiology

The maximum urethral pressure is compromised as a result of pregnancy, childbirth and related trauma, and ageing, especially following the menopause. The symptom of stress incontinence is exacerbated by obesity, chronic cough, constipation and prolapse.

Management

Conservative measures include general advice regarding fluid restriction, weight loss, avoiding bladder irritants and changing medications (e.g. diuretics). All patients should attempt pelvic floor re-education and urodynamic investigation must be performed before any surgery is considered.

Surgery is performed when conservative measures have failed and the patient’s quality of life is compromised. The options depend on the patient’s fitness for anaesthesia and whether any other prolapse exists. Burch colposuspension was the gold-standard procedure, with a success rate of 85–90%. The retropubic space is entered through a small suprapubic incision and two or three permanent sutures are placed on either side of the bladder neck to the corresponding ileopectineal ligament (see Fig. 8.7). This procedure can also be performed laparoscopically. There are a variety of ‘sling’ procedures that can be performed abdominally or vaginally, with rectus sheath, fascia lata or synthetic materials. The commonest type is the tension-free vaginal tape (TVT) procedure (Fig. 8.8), which has the advantage that it can be performed under local anaesthesia. It has success rates of between 80 and 90% and has taken over from the Burch procedure as the gold-standard treatment for USI. An alternative method of placing the mid urethral sling is via the obturator foramen and this technique is also proving an effective alternative to TVT. Anterior colporrhaphy with bladder buttress is rarely performed for stress incontinence as it has cure rates of less than 50%.

Figure 8.8 Position of midurethral tape.

Injectables or bulking agents are appropriate if previous surgery has failed or in very elderly patients. Various compounds may be used, including collagen, with success rates of 50%.

Complications for all these procedures include postoperative voiding difficulty, bleeding, infection, de novo detrusor overactivity and suture or mesh erosion (in the ‘sling’ procedure).

Causes

Management

Accurate history and examination will usually elicit the cause. The following investigations should be performed:

Treatment

Patients may need to be taught intermittent self-catheterization or may need an indwelling catheter if unable to self-catheterize. If urethral obstruction is the cause, then consider urethral dilatation or urethrolysis, which involves either a vaginal or abdominal procedure to free up the urethra.

Detrusor hypotonia may be treated with cholinergic medication and severe cases may require a urinary diversion procedure.

Assessment

Management

Often fistulae secondary to obstetric trauma may heal spontaneously. Otherwise surgical repair may be required. Surgical repair of a fistula can be performed vaginally or abdominally. When the fistula tract has been exposed it is repaired in a layered fashion and may require use of a graft (e.g. labial fat – Martius graft) to reinforce the repair.