A colonoscopy is a standard medical procedure used to diagnose and treat gastrointestinal tract conditions, particularly those affecting the large intestine (rectum, colon, and anus) and a portion of the small intestine (the ileum). It is the most effective and widely accepted screening tool for identifying colorectal cancer, the third most common cancer and the third leading cause of cancer-related deaths in the United States. Individuals over the age of 50 are advised to undergo colorectal cancer screening at least every ten years.
During a colonoscopy, the physician uses a small, flexible tube with a high-definition camera on the tip, called a colonoscope. The colonoscope also features channels for passing special instruments or fluids and LED lights to illuminate the colon. It is inserted into the patient's anus and slowly advanced through the rectum and colon. The colonoscope allows the physician to visualize the entire colon in real time and identify abnormalities such as polyps, inflammation, infections, or cancer. If abnormalities are detected, the physician can perform a biopsy or remove abnormal tissue during the procedure.
Before the procedure, patients undergo bowel preparation, which includes taking medications to increase bowel movements and following a low-residue or clear liquid diet for one to two days. Bowel preparation ensures that stool and other digestive material do not obstruct the physician’s view of the colon and helps prevent complications such as bowel perforation. Your doctor will provide specific instructions for the preferred bowel preparation method.
Patients are typically under mild sedation during the procedure, administered by an anesthesiologist. Sedation ensures comfort and minimizes movement, reducing the risk of complications. Colonoscopies are generally well-tolerated, with minimal risks that may include rectal tears, bleeding, pain, bloating, or infection.
After the procedure, any biopsies or collected tissue are sent to a laboratory for further examination. Once results are available, they will be reviewed with the patient. Based on the findings, the physician may recommend additional treatment, follow-up colonoscopies, or other interventions for re-evaluation, surveillance, or treatment.