Do not want.

"Defecography is an x ray of the anorectal area that evaluates completeness of stool elimination, identifies anorectal abnormalities, and evaluates rectal muscle contractions and relaxation. During the exam, the doctor fills the rectum with a soft paste that is the same consistency as stool. The patient sits on a toilet positioned inside an x ray machine and then relaxes and squeezes the anus to expel the paste. The doctor studies the x rays for anorectal problems that occurred as the paste was expelled."