Colonoscopy

Why Is Colonoscopy Performed?

Colonoscopy may be performed for various reasons:

1. Colorectal Cancer Screening: This is one of the most important indications. It is typically recommended starting at age 45 or 50 for individuals at average risk, and earlier for those with higher risk factors (such as a family history of colon cancer or specific genetic syndromes). It helps detect and remove polyps (small growths on the inner lining of the colon) before they develop into cancer. Since many colon cancers arise from polyps, their removal is a highly effective preventive measure.
2. Evaluation of Symptoms: Colonoscopy can help diagnose the cause of unexplained symptoms such as:
   1. Rectal bleeding or blood in the stool
   2. Changes in bowel habits (e.g., persistent diarrhea or constipation)
   3. Abdominal pain or cramping
   4. Unexplained weight loss
   5. Anemia
3. Diagnosis and Monitoring of Diseases: Used to diagnose and monitor various bowel conditions:
   1. Inflammatory bowel diseases (such as Crohn’s disease and ulcerative colitis)
   2. Diverticulosis (small pouches that can form in the colon wall)
   3. Ulcers
   4. Strictures (narrowed areas)
4. Therapeutic Purposes: Colonoscopy can also be used for treatment during the same session:
   1. Polyp removal (polypectomy)
   2. Biopsy of abnormal tissues
   3. Controlling bleeding
   4. Removing foreign objects
   5. Placing a stent to open narrowed sections

How Is Colonoscopy Performed?

The procedure usually takes 30 to 60 minutes and involves several steps:

1. Bowel Preparation: This is a crucial part of the process and typically begins one or two days before the procedure. You will need to follow a special diet (usually clear liquids) and take strong laxatives to completely empty the colon. A clean bowel is essential for clear visualization of the colon lining.
2. Sedation/Anesthesia: Before the procedure, you will usually receive intravenous (IV) sedation. This helps you feel relaxed and often induces sleep, so you won’t feel or remember the procedure.
3. Procedure: You will lie on your side, and your doctor will gently insert a lubricated colonoscope into your anus. The scope is slowly advanced through the rectum and entire large intestine. Air or carbon dioxide may be introduced to inflate the colon slightly for better visibility. A small camera at the tip of the scope transmits real-time video images to a monitor, allowing the doctor to thoroughly examine the inner lining.
4. During the Examination: If polyps or suspicious tissues are found, your doctor may remove them or take biopsy samples using small instruments passed through the scope. This is usually painless.
5. Recovery: After the procedure, you will be monitored in a recovery room for about an hour until the effects of sedation wear off. You may experience some bloating or mild cramping due to the air introduced during the procedure. Because of sedation, someone will need to accompany you home.

Benefits and Risks

Benefits:

• Comprehensive Examination: Allows thorough inspection of the entire large intestine.
• Early Detection and Prevention: Essential for identifying precancerous polyps and early-stage colorectal cancer, which greatly improves treatment outcomes.
• Biopsy and Therapeutic Capability: Enables direct tissue sampling and on-the-spot treatment of certain conditions, often eliminating the need for separate surgeries.

Risks:

Colonoscopy is generally very safe, but there are small risks associated with the procedure:

• Perforation: A tear in the colon wall (rare).
• Bleeding: Especially after polyp removal or biopsy (usually mild and self-limiting).
• Reaction to Sedation: May include nausea, respiratory issues, or other adverse effects.
• Infection: Extremely rare due to strict sterile techniques.