Colonoscopy is a procedure with minimal invasion. A flexible tube with a fiber optic camera is passed through the anus to examine the large colon[colon cancer] and parts of the small bowel.
If the presence of a polyp or an ulcer is detected an immediate biopsy can be undertaken.
Virtual colonoscopy is an even less invasive technique which helps examine a patient’s colon, the disadvantage being that in the event of a polyp or ulcer, a biopsy can’t be undertaken. The patient will then have to undergo the traditional colonoscopy.
The process of virtual colonoscopy is a little uncomfortable but does not require sedation and lasts for about 10 minutes or so. On the other hand a traditional colonoscopy requires sedation and takes longer too.
The colon of the patient is prepared just as it is done for the traditional colonoscopy. The patient is then required to lie down on the CT scan table.
The colon is then distended with gas, with the help of a thin rubber tube inserted in the rectum. Two scans are undertaken with the distended colon. One of the scans is taken while the patient is lying on their back and the other with the patient lying on the stomach.
Once the two scans are complete, a computer generates 3D images of the colon with the help of the scan images. The results on the computer very much resembles the view a physician gets during the normal colonoscopy.
A virtual colonoscopy has its advantages and disadvantages. The person undergoing the procedure needs to prepare in the same way as for the regular colonoscopy.
There is a slight chance of perforation during the traditional colonoscopy; the chances are slimmer with a virtual colonoscopy. The virtual colonoscopy is less painful and gets over in a short period of time.
The diagnosis of a traditional colonoscopy is more accurate and the need for certain procedures like biopsy can be performed immediately.
With virtual colonoscopy the results may not be as accurate and no additional procedures may be performed. Virtual colonoscopy is a safe procedure though still in its nascent stages.
A virtual colonoscopy is very expensive when compared to the traditional colonoscopy. More over in the event of finding ulcers or polyps during a virtual colonoscopy, the patient will have to undergo regular colonoscopy too.
Virtual colonoscopy has still not emerged as an alternative to the regular colonoscopy. It is recommended for those who can’t have a regular colonoscopy for various medical reasons.
It is emerging as a new technology which may be able to detect early signs of masses, thus enabling a faster diagnosis and early treatment.