Virtual colonoscopy
What is a Virtual Colonoscopy?
A virtual colonoscopy, also known as a computerized tomography (CT) colonography or CT colonoscopy, is a diagnostic procedure used to examine the inside of the colon (large intestine). It is a non-invasive procedure similar to a regular colonoscopy in that it allows doctors to visualize the interior of the colon but without surgical removal of polyps or biopsies.
Preparation for a Virtual Colonoscopy
The preparation for a virtual colonoscopy is less intense than for a traditional colonoscopy. Patients should still avoid eating solid food the day before the procedure and limit nothing but clear liquids. The primary difference is the absence of colon-cleaning medications prior to the scan.
Procedure for a Virtual Colonoscopy
A virtual colonoscopy is similar to a traditional colonoscopy in that a small tube is inserted into the rectum. The tube has a miniature camera attached to it so that the inside of the colon can be seen on a computer screen. Unlike with a traditional colonoscopy, the tube is not connected to a light source and no surgical instruments are used.
Once the tube is inserted, a CT scan is performed to obtain high-resolution images of the interior of the colon. From these images, a 3-dimensional model of the colon is constructed which can then be further examined for signs of polyps, ulcers, strictures, or other anomalies.
Types of Virtual Colonoscopy
There are two primary types of virtual colonoscopy: CT and MRI.
- CT (Computed Tomography): This uses a powerful x-ray scanner to create highly detailed images of the interior of the colon.
- MRI (Magnetic Resonance Imaging): This uses magnetic fields and radio waves to detect the position of hydrogen atoms in the body.
Risks of Virtual Colonoscopy
The risks of a virtual colonoscopy are minimal and include radiation exposure from CT scans, allergic reactions to contrast materials, infection, and bleeding. Virtual colonoscopies are generally considered to be safe when administered by a qualified physician.
Why Have a Virtual Colonoscopy?
A virtual colonoscopy is a safe and simple way to diagnose any abnormalities in the colon. It is also less expensive than traditional colonoscopies and involves less preparation and discomfort. Additionally, virtual colonoscopy results can be viewed almost immediately, speeding up diagnosis and treatment.
When Should a Virtual Colonoscopy Be Done?
A virtual colonoscopy should be considered for any adult who is 50 years of age or older, or for anyone with a family history of colon cancer. Additionally, those with any symptoms of colon cancer such as abdominal pain, changes in bowel habits, or rectal bleeding should consider having a virtual colonoscopy.