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.
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.
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.
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.