A proctoscopic exam, sometimes confused with a colonoscopy, refers to an examination of your anal cavity with a proctoscope. The proctoscope ranges from 5 to 10 inches long and is inserted into the anal cavity for medical examination. Unlike the colonoscope, the proctoscope is rigid and cannot twist and bend, limiting its use to the most outward section of the digestive tract.
Proctoscope
The proctoscope is a short metal and hollow tube that often has a light source at the end of it to illuminate the physician's view of the rectal cavity. A shorter proctoscope is sometimes called an anoscope, while the longest proctoscopes are sometimes referred to as rectoscopes. As the proctoscope is rigid and inflexible, insertion of the proctoscope can be more uncomfortable for the patient than the flexible sigmoidoscope and colonoscope.
Purpose
A proctoscopy typically is undertaken to examine for the presence of anal polyps and hemorrhoids. The physician or other medical professional lubricates the proctoscope and inserts it into the rectum. The physician can look through the proctoscope to view the anal cavity to look for abnormalities. The proctoscopy also can be a medium to take biopsies of polyps in the rectum. Proctoscopy also may be used to diagnose unexplained rectal bleeding.
Comparison to Colonoscopy
While a proctoscope can allow a doctor to view only the most anterior portion of the anal cavity and digestive tract, a colonoscopy can examine deep into the large intestine. A colonoscope can facilitate this because it is small and flexible in comparison to the proctoscope. Unlike a proctoscopy, a colonoscopy generally requires mild anesthesia. However, similar to a proctoscopy, the colonoscopy examines the digestive tract for abnormalities such as polyps and hemorrhoids.
Preparation
Prior to a proctoscopic examination, your doctor will likely have you perform several preparatory steps. Your physician may prescribe a laxative for you to take the evening before your procedure. The laxative will clean out your bowel and prevent obstructions during the examination. Your physician also likely will request that you not eat any solid foods after the middle of the day prior to the examination. This ensures your doctor can easily view your digestive tract.