Pelvic organ prolapse is a common and growing condition, especially with the changing demographic of the world's population. Disorders of the posterior pelvic floor are associated with significant anatomic and functional derangements, which have been reported in 24 to 67% of patients with pelvic organ prolapse. Understanding, diagnosing, and treating posterior pelvic floor dysfunction requires a thorough physical examination, quality of life questionnaires, and imaging studies such as defecography to evaluate the mechanics of defecation and its relationship to other pelvic organs. The objectives of this video are to discuss the indications of defecography, describe the technique of performing defecography, discuss the objective measurements, and show examples of normal and abnormal findings on defecography. Defecography is a well-established and widely available method of evaluating the dynamics of rectal emptying and pelvic floor visualization. Defecography can be useful in patients where physical exam and history fail to reveal the etiology of patient's symptoms. Many studies have shown defecography to be a useful, adjunctive study for evaluating and treating patients presenting with pelvic organ prolapse. Because defecography provides a near-physiologic evaluation of evacuation, it is indicated in the evaluation of constipation or obstructed defecation, rectocele, rectal prolapse, rectal interception, enterocele, sigmoidoscele, fecal incontinence, and descending perineum syndrome. The rectum may be emptied by giving glycerin suppositories prior to the procedure. A dilute perium suspension, as shown here, is given orally 30 to 45 minutes prior to the procedure. Before oral contrast and glycerin suppositories are given, intravaginal barium paste using a small caliber syringe or a tampon is inserted for vaginal opacification. This allows visualization of vaginal displacement during evacuation. With the patient in the supine lateral position, the rectum is opacified using a commercial barium paste, as shown here. Alternatively, barium can be added to potato or oatmeal mixes. Contrast is injected into the rectum using plastic syringes or an injector such as a caulking gun. A small amount of paste is left in the anal canal and on the anal opening to provide their exact identification. Radio-opaque markers can be placed on the perineum. Once the pelvic organs are opacified, the patient then sits on a radiolucent commode which is attached to the fluoroscopic table and seated sideways to allow lateral view imaging of the rectum. Images are taken with the patient sitting in lateral position at rest, performing a voluntary contraction of the pelvic floor during valsalva maneuver and during defecation. Once the patient voids, the patient is asked to continue pushing for at least two minutes to allow for visualization of pelvic organs. This helps in the identification of anterosclerosis, intussusception, or rectal prolapse that may be missed when examining a patient in the supine position. Measurements taken can include the anorectal angle, descent of the rectum, rectal wall abnormalities, evacuation time, and completeness. This video is a normal defecography study. The small bowel is outlined in green, vagina blue, and the rectosigmoid in brown color. The anorectal angle shown by the yellow lines is the angle between the posterior border of the distal rectum and the central axis of the anal canal. The anorectal angle decreases with voluntary contraction of the pelvic floor and increases with straining. As the patient voids, the patient is able to completely evacuate her rectum. The small bowel is not displaced. This study shows a patient with a posterior compartment defect. The small bowel, vagina, and rectum are again outlined. A distal rectocele is noted along with a large entrocele, filling the rectovaginal space with straining and defecation. This study shows the evaluation of a patient with obstructed defecation. Note the acute anorectal angle. There is poor relaxation of the levator sling as the anorectal angle remains an acute angle throughout the numerous attempts at defecation. Once again, there is minimal change in the anorectal angle as the patient attempts to evacuate the rectum. Compare this to our first normal study. This patient is only able to excrete a small amount of barium with each attempt. On the final image, the rectum is essentially empty. This study shows a patient presenting with symptoms of constipation and difficulty evacuating the rectum. No anorectal pathology was seen on physical examination in dorsal supine lithotomy position. Again, the small bowel, vagina, and rectum are outlined. Also noted is an anterorectocele. The rectum empties with straining. The patient continues to strain as she feels that the rectum is not fully evacuated. With continued straining, there is a definite rectal-rectal intussusception noted. On the magnified image, the rectal-rectal intussusception, circled here in yellow, is again seen with rectal prolapse and at completion. This study shows a patient with a history of constipation and pain and bleeding with bowel movements. Physical exam in the dorsal supine lithotomy position failed to reveal any abnormalities. Erectocele is easily noted, which does not empty with straining. An enterocele is also noted. With repeated valsalva maneuver, a rectal prolapse is also seen. This still image highlighting the small bowel, vagina, and rectum shows a trapped rectocele and the leading edges of the rectal prolapse. Also note the posterior deflection of the vaginal axis. The full thickness rectal prolapse is shown here in the arrows. In conclusion, the results from defecography can be used for determining management plans and for guiding choice of surgical procedure. Defecography improves our understanding of the interrelationships of the pelvic organs and provides accurate radiographic display of concurrently occurring pelvic floor abnormalities.

pelvic organ prolapse

posterior pelvic floor dysfunction

defecography

rectal emptying

pelvic floor dynamics