Rectocele Workup

Updated: Apr 24, 2017
  • Author: Howard A Shaw, MD, MBA; Chief Editor: Kris Strohbehn, MD  more...
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Approach Considerations

Consider performing ancillary testing to ensure the patient has been evaluated for other types of pelvic floor dysfunction. The tests usually considered are physiological tests of bladder and rectal function and imaging tests to clarify anatomical derangements. Note the following:

  • Urodynamic testing is commonly used for patients with urinary incontinence in addition to pelvic organ prolapse, although the benefit of urodynamic testing in women without urinary incontinence is controversial.

  • Urodynamic testing with reduction of the posterior vaginal wall is recommended in patients with an equivocal diagnosis. Similarly, anorectal physiologic testing may be useful in patients with suspected anismus or concurrent fecal incontinence.

The most important consideration in a patient with rectocele is the presenting symptoms. In women with isolated herniation symptoms consistent with rectocele, further testing is probably not required.


Laboratory Studies


Imaging Studies


In women with defecatory dysfunction, a gastrointestinal evaluation, including a barium enema or colonoscopy, is recommended to eliminate colorectal malignancy from the differential diagnosis. Anoscopy may reveal anorectal pathology such as prolapsing hemorrhoids, and proctosigmoidoscopy helps to exclude intrarectal prolapse or a solitary rectal ulcer. Occasionally, referring the patient to an anorectal physiology laboratory may be necessary. This may be necessary to differentiate between patients with colonic motility disorders and those with predominant pelvic outlet symptoms.

Other radiologic studies that may be useful include the colonic transit study, pelvic floor fluoroscopy, and dynamic magnetic resonance imaging. Colonic transit studies involve the use of ingested radiopaque markers, followed by serial abdominal radiographs over a 5-day period. The woman ingests a capsule with 24 radiopaque markers, and then serial abdominal radiographs are taken every other day until all the markers are gone. Eighty percent of these markers should be passed by day 5. If less than 80% are passed, this suggests a motility disorder. Collection of the markers in the sigmoid is suggestive of outlet obstruction but is not diagnostic. The colonic motility test is primarily indicated for patients with a suspected motility disorder based on abnormal stool frequency (less often than every 3 d).

Pelvic floor fluoroscopy may be useful for patients with pelvic organ prolapse and severe defecatory dysfunction. It can be especially useful for women who report incomplete evacuation because it helps to differentiate causes of outlet obstruction such as anismus and support defects. The small bowel is opacified with oral contrast, the vagina and bladder with liquid contrast, and the rectum with contrast paste. A series of sagittal still films and cinevideographs are made with fluoroscopy while the patient sits and defecates on a radiolucent commode. Radiographs are taken at rest, during defecation, and while squeezing the anal sphincters. The size of the rectal ampulla, length of the anal canal, size of the anorectal angle, motion of the puborectalis, and degree of pelvic floor descent are measured. This provides both radiologic evidence of herniation of the surrounding organs into the vagina and dynamic assessment of pelvic floor function during defecation.

Rectoceles are commonly found on proctograms, and small bulges of the anterior rectal wall detected upon evacuation proctography might be normal findings because they are frequently asymptomatic. Rectoceles should be considered abnormal if barium trapping (the rectocele does not completely empty upon evacuation) is noted.

Pelvic floor fluoroscopy is considered the criterion standard for measuring perineal descent and is more accurate than physical examination for defining which organ is herniating into the vagina. However, it is usually reserved for patients with marked defecatory dysfunction.

Dynamic magnetic resonance imaging provides a similar evaluation. It also provides multiplanar information about the soft tissues of the pelvic floor. The most appropriate use of this test is for patients with complex pelvic organ prolapse or symptoms that are not explained by the physical examination findings.

Anismus can mimic the defecatory symptoms of posterior pelvic organ prolapse and can cause posterior pelvic organ prolapse as a result of outlet obstruction. This should remain a consideration in the differential diagnosis. Anismus is usually suspected in patients with tender, hypercontracted puborectalis muscles upon bimanual examination, especially if she cannot relax these muscles on command. Pelvic floor fluoroscopy can provide evidence of anismus, including lack of straightening of the anorectal angle and failure to evacuate two thirds of contrast after 30 seconds of straining. However, a balloon expulsion test and surface electromyography are considered superior for making the diagnosis of anismus.