A CT colonography, often referred to as a virtual colonoscopy, is a diagnostic imaging procedure used to examine the large intestine. Many express concern about pain. Severe pain is not typical, but some discomfort is common during the procedure. The process is generally well-tolerated, and understanding what to expect can help manage anxieties. This article details the preparation, scan, and immediate aftermath.
The Preparation Journey
Preparation for a CT colonography is often the most challenging part. This step is designed to thoroughly cleanse the bowel, ensuring clear images for accurate diagnosis. Patients typically begin a low-fiber diet a few days before the procedure, transitioning to a clear liquid diet the day prior to the scan. This diet reduces solid waste in the colon.
Preparation involves laxatives or bowel cleansing agents. These medications are essential for emptying the colon, but they can cause frequent bowel movements, abdominal cramping, and bloating. Patients are advised to remain near a toilet during this period due to the laxative effects. Staying hydrated with clear fluids is important to prevent dehydration. Some preparations may also include oral contrast agents, like Gastrografin, which help distinguish any remaining stool from polyps on the scan.
During the Scan: Addressing Discomfort
During the CT colonography, the primary sensation is colon inflation. A small tube is inserted into the rectum to introduce air or carbon dioxide (CO2), expanding the bowel for optimal visualization. While this process is not typically painful, it can lead to feelings of fullness, pressure, or bloating, similar to needing to pass gas.
Many facilities use carbon dioxide for insufflation, which is absorbed faster than room air, minimizing post-procedure discomfort. Patients may be asked to change positions, typically lying on their back, stomach, or sides, to allow for comprehensive imaging of the colon from different angles. The actual scanning takes 10 to 30 minutes. Medical staff are present throughout the procedure to monitor the patient and provide reassurance.
After the Scan: Immediate Sensations
After the CT colonography, discomfort from the scan resolves quickly. The air or carbon dioxide used to inflate the colon is naturally expelled or absorbed by the body. Patients may experience mild abdominal discomfort, bloating, or increased gas for a few hours.
Most individuals can resume their normal activities and diet immediately after the scan, as no sedation is typically required for a CT colonography. While minor, temporary sensations are common, significant or prolonged pain is unusual. Drinking fluids for a day or two helps alleviate lingering discomfort and rehydrate. If muscle relaxants are administered, temporary side effects like blurred vision or dry mouth may occur, subsiding within 30 to 60 minutes.