During Your Doctor's Visit: The Rectal Exam

Many people dread going to the doctor to get their hemorrhoids checked for obvious reasons: it's embarassing and uncomfortable.

However, an annual rectal exam is an important first step in ruling out more serious matters, such as colorectal cancer. Did you know that if detected early, this form of cancer has a good chance of being treatable. Thousands of cases of cancer can even be prevented!

Before The Rectal Exam Begins

To allow the proper examination of the colon and rectal walls, your doctor may recommend that you clean your bowel with an enema, a liquid diet, or a laxative before the rectal exam.

Depending on your doctor, he or she may ask you to undress and lie on your side, or to kneel with your shoulder and side of your face on a table. Some doctors may have a special hydraulic table, with a ledge to kneel on. This type of table has a foot pedal, with which your doctor can rise and tilt the table prior to the examination.

Digital Examination

The first thing your doctor will do is conduct a visual examination of the anus and surrounding area to see if you have any rash, fissure, fistula, as well as external or prolapsed hemorrhoids.

Next, your doctor will slowly insert a gloved and lubricated finger into the anal opening, and rest it there to let the anal sphincter muscle relax and for you to get used to the sensation. Then, your doctor will slowly insert the finger deeper and massage the anal opening gently to stretch it wider. This allows your physician to feel a woman's cervix or a man's prostate through the rectal wall and find out if there are any bulges that may be an indication of tumor, enlarged prostate, abscesses, or trapped foreign objects.

Anoscopy - Examination with an Anoscope

Afterwards, your doctor may use a device called an anoscope to do a visual examination of the rectum. An anoscope is a tube about 3-inches in length with light attached to it. This device allows your doctor to see if there are any internal hemorrhoids and polyps in the rectum, as well as protruding tissues from the dentate line.

Sigmoidoscopy - Examination with a Sigmoidoscope

If there is anything unusual, your doctor may refer you to a proctologist or a gastroenterologist. These specialists will use a specialized device called a sigmoidoscope to inspect the first 25 inches of the colon.

The sigmoidoscope is a rubber-like tube can be guided. It also has glass fibers that can transmit light, as well as allow the doctor to see from the outside end of the instrument. New sigmoidoscopes have cameras that can transmit digital pictures to a monitor.

In this exam, you will lie on your left side parallel to the floor. The doctor would then insert the lubricated sigmoidoscope into the anal canal and guide it around the colon's twist and turn. The doctor will look for polyps, tumors, and infections.

During a sigmoidoscopy, you may feel discomfort or crampings as the doctor maneuvers the instrument in and out of the colon. As the sigmoidoscope is retracted, you may even feel the urge to defecate as it presses the valves of Houston in the rectum.

Colonoscopy - Examination with a Colonoscope

If your doctor finds polyps or lesions within the last 25 inches of the colon, a follow up examination with a colonoscope is performed. This is because growth in the rectum is often accompanied with lesions in the upper parts of the colon.

A colonoscope is basically a longer sigmoidoscope - instead of 25 inches, it is 75 inches in length - long enough to investigate the entire bowel. It has a special attachment that can snip off polyps or cauterize a growth with electricity.

In this exam, your doctor will have you lie on your side with your knees bent. Because of possible discomfort and crampings, he or she may even prescribe a local anesthesia before the procedure is performed.

"Virtual" Colonoscopy

A virtual colonoscopy uses a CT (or Computed Tomography) scan of the abdominal area to obtain a series of cross sectional pictures of the colon and rectum from different angles. A computer program is then used to assemble the images into a "film" that runs the entire length of the colon. Your doctor would then watch the film for signs of polyps.

If polyps are discovered, a conventional colonoscopy is then performed to remove them.

Although virtual colonoscopy is relatively new, it holds the promise of a more comfortable way to examine the colon as it is less intrusive than a conventional colonoscopy. Recent studies have suggested that virtual colonoscopy is just as effective as conventional methods for detecting polyps and lesions. Nevertheless, you would still be required to clean your bowel by a liquid diet or laxative prior to the procedure.

Barium Enema

Although colonoscopy is the preferred method of examining the colon for polyps and tumors, an alternative method of using a barium enema can be performed. It can also be used to confirm the result of a colonoscopy and to make sure that no other lesions and polyps are left undiscovered.

In this procedure, you will be given an enema with a solution of barium sulfate, followed with an X-ray exposure. The barium liquid is impervious to X-ray and will delineate any bulges due to polyp, tumor, or ulcer in the colon.

In a slightly different procedure called a double exposure barium enema, air is blown into the rectum and colon to enhance the contrast and help in the identification of lesions.

Similar to sigmoidoscopy and colonoscopy, your doctor may have you clean your bowel by a liquid diet or laxative prior to the procedure. Also, crampings and discomfort may occur during the short examination.