Brain 17 Vienna

Radiobiology in the CNS: the vascular effect (SRS)

• Mainly for the case of benign lesions (AVM and meningioma, namely) large parte of the effect is determined by the combination of:  Citotoxic effect of the high dose of radiation with direct double strand DNA damage  Vascular injury with doubled number of apoptotic cells in the first 48 hours  Such a vascular effect is seen on tumor and AVM, but not in normal vessels (different vascular/endothelial radiosensitivity)  The probability of vascular damage is directly proportional to the fraction dose (particularly when higher than 10 Gy!!!)  High dose induces reduction of vascular mass and increase of vascular permeability

Park and Griffin, Rad Res., 2012