Intensity Modulated Radiation Therapy (IMRT) – Computerized Precision

In intensity modulated radiation therapy (IMRT), very small beams are aimed at a tumor from many angles. During treatment, the radiation intensity of each beam is controlled, and the beam shape changes hundreds of times during each treatment. As a result, the radiation dose bends around important healthy tissues in a way that is impossible with other techniques. Because of the complexity of these motions, Verity Radiation uses special high-speed computers, treatment-planning software, diagnostic imaging and patient-positioning devices to plan treatments and control the radiation dose during therapy.

For IMRT to be effective, the anatomical position of the tumor and surrounding healthy tissues must be accurately defined. CT, PET scans and MRIs provide the necessary three-dimensional anatomical information, while advanced imaging devices provide daily information about the location of internal organs.

A device called a multileaf collimator adjusts the size and shape of the computer-determined radiation beams. The collimator, a computer-controlled mechanical device, consists of dozens of individually adjusted metal leaves. These leaves move across the irradiated tissue while the beam is on, blocking out some areas and filtering others to vary the beam intensity and precisely distribute the radiation dosage.