Image Guided Radiotherapy (IGRT) Trilogy

The goal of the IGRT process is to improve the accuracy of the radiation field placement, and to reduce the exposure of healthy tissue during radiation treatments. In years past, larger planning target volume (PTV) margins were used to compensate for localization errors during treatment. (Jaffray et al. 1999) This resulted in healthy human tissues receiving unnecessary doses of radiation during treatment. PTV margins are the most widely used method to correct geometric uncertainties. By improving precision and accuracy through IGRT, radiation is decreased to surrounding healthy tissues, allowing for increased radiation to the tumour for control. (Jaffray et al. 1999) References: Jaffray, DA; JP Bissonnette, T Craig [1999]. "X-ray Imaging for Verification and Localization in Radiation Therapy in Modern Technology of Radiation Oncology (suppl. 1)", Modern Technology of Radiation Oncology. ISBN 0-944838-38-