What is the pathophysiology of cystocele and rectocele?

From the Guidelines

The pathophysiology of cystocele and rectocele involves the weakening of pelvic support structures, leading to the herniation of the bladder or rectum into the vaginal canal, resulting from damage to the levator ani muscles, endopelvic fascia, and vaginal wall connective tissue, as supported by the most recent study 1.

Pathophysiology of Cystocele and Rectocele

The weakening of pelvic support structures is a key factor in the development of cystocele and rectocele. A cystocele occurs when the supportive tissue between the bladder and vagina (pubocervical fascia) weakens or tears, allowing the bladder to herniate into the vaginal canal. This typically results from damage to the levator ani muscles, endopelvic fascia, and vaginal wall connective tissue. Common causes include childbirth trauma, chronic increased intra-abdominal pressure (from obesity, chronic coughing, or heavy lifting), aging, and estrogen deficiency after menopause which reduces tissue elasticity and strength, as noted in 1.

Causes and Risk Factors

Similarly, a rectocele develops when the rectovaginal fascia between the rectum and vagina weakens, permitting the rectum to bulge into the posterior vaginal wall. Both conditions represent a form of pelvic organ prolapse resulting from compromised integrity of the pelvic floor support system. These anatomical defects can cause symptoms including urinary issues (frequency, urgency, incontinence) with cystocele, and bowel dysfunction (constipation, incomplete evacuation) with rectocele. The severity depends on the extent of tissue damage and the degree of organ displacement into the vaginal canal, as discussed in 1 and 1.

Diagnostic Evaluation

Initial evaluation of patients with pelvic floor dysfunction is clinical, with history and physical examination forming key elements of patient evaluation. However, physical examination may be limited in terms of depicting the multicompartment involvement of pelvic floor dysfunction. Imaging tests such as fluoroscopy, MRI, and ultrasound (US) provide global information about the pelvic floor and may be of particular benefit in areas where clinical evaluation is limited, as mentioned in 1.

• The use of MRI defecography allows for comprehensive anatomic and functional evaluation of the entire pelvic floor, as noted in 1.
• Fluoroscopic cystocolpoproctography (CCP) demonstrates good agreement with surgical findings for detection of full-thickness rectal prolapse, posterior colpocele, rectocele, and peritoneocele, as discussed in 1.
• Dynamic CCP involves fluoroscopic imaging during defecation with the patient sitting in physiologic upright position on a fluoroscopic commode, providing a functional evaluation of the pelvic floor, as described in 1.

From the Research

Pathophysiology of Cystocele

• Cystocele is the protrusion of the bladder into the vagina, which occurs when the muscles and tissues that support the bladder are weakened 2.
• The pathophysiology of cystocele involves the failure of the fibromuscular supports of the pelvic floor, including the pubocervical fascia, tendinous arcs, endopelvic fascia, and levator ani muscle 2.
• DeLancey's theory and Petros's integral theory are two complementary theories that explain the mechanism of cystocele, with DeLancey's theory focusing on the three-level anatomopathologic definition of prolapse and Petros's theory emphasizing the interdependence between pelvic organ support systems 2.
• Anterior vaginal wall prolapse, including cystocele, can present as stress incontinence, and a large cystocele can cause urethral kinking and overflow incontinence 3.

Pathophysiology of Rectocele

• Rectocele is the protrusion of the rectum into the vagina, which occurs when the muscles and tissues that support the rectum are weakened [(4,5)].
• The pathogenesis of rectocele is still controversial, but it is thought to involve defects in the integrity of the rectovaginal septum 5.
• Rectocele can cause symptoms such as incomplete evacuation of stool, constipation, and pelvic pain [(4,3,5)].
• Internal rectal prolapse may simulate a rectocele or enterocele and requires defecography to establish the diagnosis 4.

Relationship between Cystocele and Rectocele

• Cystocele and rectocele often coexist with other pelvic floor defects, including uterine prolapse, vault prolapse, and enterocele [(4,3,6)].
• The correction of prolapse must aim to restore vaginal function and any concomitant urinary incontinence 3.
• Surgical management of cystocele and rectocele must take into account several factors, including the presence of stress urinary incontinence, prior hysterectomy, and the desire to maintain sexual activity 6.