Rectocele

See Anorectal Physiology Testing for the diagnostic toolkit referenced below. Content below is from a textbook reference chapter (Sabiston Ch52 - Pelvic Floor Disorders & Constipation), not primary literature.

Overview

A bulging of the anterior wall of the rectum into the posterior wall of the vagina. Most common risk factors: advanced age, history of pregnancy and vaginal childbirth, increasing BMI, chronically elevated intraabdominal pressure, and history of hysterectomy. Multifactorial cause — a muscular and/or neurologic defect to the rectovaginal septum (usually from obstetric trauma), plus the effect of chronic straining on the endopelvic fascia and posterior vaginal wall. Can be associated with other pelvic organ prolapses.

Most rectoceles are asymptomatic. When symptomatic, the cardinal symptom is difficulty with rectal emptying and the need to press against the posterior vaginal wall or the perineum to complete emptying (splinting) — a form of obstructed defecation. Other symptoms: sensation of a vaginal bulge, urinary and/or sexual dysfunction, constipation, and — in some cases — fecal incontinence (thought to result from fecal trapping within the rectal pocket allowing post-defecatory leakage, an associated mucosal prolapse impairing anal closure, or overflow incontinence).

Diagnosis

Mainly clinical, based on physical exam. Digital vaginal and rectal exams show a bulge in the posterior vaginal wall and anterior rectal wall during straining, which can be associated with the prolapse of other pelvic organs and with an anterior cystocele. Associated stress urinary incontinence is assessed by having the patient cough or perform a Valsalva maneuver with a full bladder.

On defecography, a rectocele appears as a bulging of the rectal wall toward the vagina, graded small (<2 cm), moderate (2–4 cm), or large (>4 cm). This test also shows possible trapping of contrast within the rectocele during defecation, and possible association with an enterocele or sigmoidocele. Dynamic MRI and MRI defecography are limited by being performed with the patient supine (not the normal upright defecation position), so the degree of anatomic distortion often does not correlate with the degree of functional impairment/symptoms. The balloon expulsion test can identify inability to expel an inflated balloon after 4 minutes sitting on a commode.

Management

Asymptomatic rectoceles need no treatment. Symptomatic rectoceles are initially managed with a bowel regimen and fiber products to improve defecation. Only patients with markedly symptomatic rectoceles unresponsive to medical treatment are candidates for surgery. The goal of surgery is to remove the redundant tissue of the rectocele and strengthen the rectovaginal septum.

• Transvaginal approach (preferred by gynecologists): better visualization/access to the levator muscles. A local anesthetic with epinephrine or vasopressin is injected below the vaginal mucosa to dissect the tissue and for hemostasis. The vaginal epithelium is opened in the posterior midline to the upper level of the defect; the fibromuscular layer is exposed and plicated in the midline with vertically or transversely placed sutures. The puborectalis can be reapproximated. Surplus vaginal epithelium is trimmed and sutured with absorbable sutures.
• Endorectal repair (performed by colorectal surgeons, patient in prone jackknife position): a local anesthetic with epinephrine or vasopressin is injected in the submucosal plane for dissection/hemostasis. A T-shaped or midline incision is made in the rectal mucosa just above the dentate line. Two lateral mucosal flaps are developed on either side of the midline to a level proximal to the rectocele. The excess rectal mucosa is excised and the underlying muscularis layer is exposed and plicated with transversely placed absorbable sutures; the mucosal edges are then approximated with absorbable sutures.
• Transperineal repair: performed via a transverse incision across the bulbocavernosus and transverse perineal muscles; the two limbs of the puborectalis muscle are reapproximated. A mesh can be placed to reinforce the plasty. Especially indicated in patients with associated fecal incontinence, since a concomitant sphincteroplasty or levatorplasty can be performed at the same time.

Open items / gaps

• No primary trial data comparing transvaginal, endorectal, and transperineal repair outcomes head-to-head.
• No specific recurrence-rate figures given for any of the three repair approaches — a gap worth filling with a dedicated source if a specific approach decision needs data behind it.