The Tomotherapy HI-ART System combines both CT scanning technology with Intensity Modulated Radiation Therapy, or IMRT. Initially, a CT scan is performed on the affected region in order to establish the exact contours of the tumor and the surrounding healthy tissue and therefore determine the dose of radiation.
Based on this data, the Tomotherapy HI-ART System uses a computer-controlled multi-leaf collimator to adjust the intensity and shape of the radiation beam. The "leaves" of this device periodically move in and out contouring the radiation beam to the shape of the tumor. These beams can enter the body at 360 degrees in order to maximize tumor dosage and protect healthy adjacent tissue.
Each rotation will treat a slice of the tumor target, precisely focusing the radiation around the entire tumor.The overall effect is to protect the normal tissue, by only exposing it to a small dose of radiation, while the tumor receives a larger, potentially more effective dose.