BACKGROUND AND PURPOSE: Radiation-induced cognitive dysfunction is a common and serious clinical complication after radiation therapy for a brain tumor, but the knowledge of its mechanism is poorly understood. The purpose of this study was to establish a young rat model for acute radiationinduced cognitive dysfunction and associated BBB damage, as well as histopathologic changes.

BACKGROUND AND PURPOSE: Radiation-induced cognitive dysfunction is a common and serious complication after radiation therapy of brain tumor, yet knowledge of its mechanism is poorly understood. The aim of this study was to establish a young rat model for acute radiation encephalopathy, at both cognitive and pathologic levels, induced by fractionated irradiation.