Permeability of Brain Tumor Vessels Induced by Uniform or Spatially Microfractionated Synchrotron Radiation Therapies

Microbeam radiation therapy-induced increased tumor vascular permeability is: (1) significantly greater; (2) earlier and more prolonged than that induced by BB irradiation, especially in highly proliferative tumor areas; and (3) targets all tumor areas discriminated by physiologic characteristics, including those not damaged by homogeneous irradiation.