What is Sigmoidoscopy? Overview, Benefits, and Expected Results
Sigmoidoscopy is a medical procedure in which a special instrument, a sigmoidoscope, is used to examine the lower part of the large intestine, also known as the colon or the large bowel. This type of procedure is usually used to detect problems and abnormalities within the large bowel, such as cancer, polyps, inflammation, and bleeding. During a sigmoidoscopy, the doctor makes use of the sigmoidoscope’s small, lighted tube to view and examine the lower part of the large intestine. Depending upon the results of the sigmoidoscopy, further tests might be suggested or a biopsy may be taken.
Types of Sigmoidoscopy
There are two main types of sigmoidoscopy – flexible and rigid sigmoidoscopy.
Flexible sigmoidoscopy, also called a flexible sigmoidoscopy, makes use of the latest fiber-optic technology and is usually done in the doctor’s office. This type of sigmoidoscopy is painless and typically takes 15 minutes or less to perform. The flexible sigmoidoscope is inserted through the anus and advanced to the descending colon. The doctor is then able to look at the lower part of the large intestine.
Rigid sigmoidoscopy is done primarily in the operating room or a hospital setting. This type of sigmoidoscopy makes use of a metal tube that allows the doctor to take a biopsy and enable them to obtain a better view of the lining of the lower part of the large intestine.
Benefits of Sigmoidoscopy
Sigmoidoscopy is usually a safe procedure; however, it is important to note that discomfort can occur during the test. That being said, there are several benefits associated with this type of procedure:
- Sigmoidoscopy is an effective diagnostic tool that can help to detect various conditions in the lower part of the large intestine.
- The procedure is relatively painless and typically takes only a few minutes to perform.
- Sigmoidoscopy can provide important information about the health of the large intestine.
- The procedure is relatively non-invasive and does not require an overnight stay in the hospital.
- Sigmoidoscopy can reduce the likelihood of certain types of colorectal cancers.
Sigmoidoscopy Expected Results
The expected results of a sigmoidoscopy depend on the type of procedure performed. In general, a doctor can detect abnormal growths or lesions, bleeding, inflammation, and polyps in the lower part of the large intestine.
Flexible Sigmoidoscopy Results
When a flexible sigmoidoscopy is done, the doctor can detect any potentially harmful lesions or abnormal growths. If these abnormalities are detected, follow-up tests, such as CT scan, may be suggested.
Rigid Sigmoidoscopy Results
When a rigid sigmoidoscopy is performed, the doctor can detect any potentially harmful lesions or abnormal growths as well as take biopsies of the tissue. Biopsies help to accurately identify the cause of the problem and can help the doctor determine the best course of action.
Possible Complications and Side Effects of Sigmoidoscopy
There are a few potential side effects and complications associated with sigmoidoscopy, such as:
- Vaginal bleeding
- Upper respiratory tract infection
- Nausea and vomiting
- An increase in the intensity of pelvic pain
- A feeling of abdominal discomfort
In some rare cases, sigmoidoscopy can lead to more serious complications, such as:
- Tear in the large intestine
- Perforation of the large intestine
- Severe abdominal pain
- High fever
Preparing for a Sigmoidoscopy
If your doctor has recommended a sigmoidoscopy, here is what you need to do to prepare for this procedure:
- Ask your doctor about the type of sigmoidoscopy they will be performing.
- Follow your doctor’s instructions regarding medications and any other activities that might interfere with the procedure.
- Discuss any health concerns with your doctor.
- Avoid eating solid foods for 8-12 hours prior to the procedure.
- If your doctor recommends a liquid diet, follow it 24 hours prior to the procedure.
- Follow your doctor’s instructions regarding the use of laxatives and enemas prior to the procedure.
- Do not take any antacids for 24-48 hours prior to the procedure.
- Make sure you make arrangements for someone to drive you home after the procedure.
Sigmoidoscopy is an effective medical procedure that can help detect problems and disorders in the lower part of the large intestine. The procedure is relatively painless and involves inserting a sigmoidoscope into the lower part of the large intestine. There are two types of sigmoidoscopy: flexible and rigid. Flexible sigmoidoscopy is conducted in a doctor’s office while rigid sigmoidoscopy is done in an operating room. Sigmoidoscopy carries potential risks, so it is important to ask your doctor about any questions or concerns prior to the procedure.
Definition and Overview
Sigmoidoscopy is a test that looks into the last section of the colon, which is composed of the rectum, sigmoid colon, and the anus. It uses a device called bowel scope, a long, narrow, and flexible tube with an attached camera that feeds real-time images to a monitor and light that illuminates the sections being checked.
Sigmoidoscopy is different from colonoscopy, although both are intended to investigate issues affecting the gastrointestinal tract. While colonoscopy checks the entire colon, sigmoidoscopy focuses on the sigmoid colon, which is the last section of the large intestine that is connected to the rectum.
The procedure is performed on an outpatient basis and requires some preparation. There will be some mild discomfort, pressure, and pain after the procedure, but they’re expected to go away over time.
Who Should Undergo and Expected Results
Sigmoidoscopy is performed for a number of reasons, including the following:
- There are changes in the bowel movement – Regular bowel movement can differ for every person, but often, it is consistent. The procedure is recommended if a person experiences recurrent diarrhea, constipation, or alternate diarrhea and constipation so the cause can be determined.
- Stool has blood and/or mucus– Blood and mucus in the stool can indicate infection, perforation of the sigmoid colon, hemorrhoid, [anal fissure] when only a small amount of food has been consumed. Other symptoms include loss of appetite, malnutrition, and unexplained weight loss.
Sigmoidoscopy can also be a part of a colon cancer screening. The US Preventive Services Task Force (UPSTF) recommends screening for colon cancer at age 50 or earlier if there’s a genetic or hereditary risk. Sigmoidoscopy is then performed every five years.
Sigmoidoscopy can reveal any perforation, ulceration, or growth of polyps in the colon, as well as tearing or bleeding in the rectum and anus.
How Does the Procedure Work?
Sigmoidoscopy can be performed by a general physician, an internist, or a gastroenterologist. Before the exam, the doctor will advise the patient to avoid taking medications, such as blood thinners, that can promote bleeding.
A significant part of the procedure is the bowel preparation, which involves getting rid of the stool in the colon. The doctor typically recommends a special diet like soups, broth, and tea. At least an hour before the procedure, the patient also undergoes an enema.
The procedure is often done on an outpatient basis either in a clinic or a hospital. Sedatives can be used to help the patient relax especially if the patient is a child so unnecessary movements can be minimised during the procedure.
The patient then lies on his side with his knees brought to the chest (foetal position). The doctor will begin by performing a digital rectal exam to check for any physical abnormality in the anus and rectum.
He will then proceed checking the sigmoid colon by gently and slowly inserting the bowel scope into the anus and rectum. As the probe enters, air is also introduced to further expand the colon. The camera provides the doctor with real-time images on a computer monitor helping him assess the affected organs.
Depending on what he sees, the doctor may remove a polyp for biopsy, obtain other samples for culture testing, determine if there’s any infection, or trace the source or cause of the inflammation, abscess, or ulceration. If there’s a polyp present, a colonoscopy will be most likely to be performed as well.
Once the procedure is complete, the doctor will slowly remove the bowel scope from the colon and anus. It usually takes around 20 minutes to complete the test.
Possible Risks and Complications
- Passing stool or gas when air is introduced
- Perforation or tearing of the colon
- Discomfort and pressure during the digital rectal exam
- Dizziness or nausea after the exam
- Abdominal cramps
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