Temporal Alterations in Brain Water Diffusivity in Acute Radiation Injury

Richa Trivedi¹, Hemanth Kumar Bhonsle Somu¹, Senthil Veeramani¹, Rajendra P. Tripathi¹, Subash Khushu¹

Longitudinal diffusion tensor imaging (DTI) study was performed at baseline, 6 h, 1 day, 3 days and 5 days after a sub-lethal dose irradiation. Decreased MD values were observed in brain parenchyma at 3rd and 5th day compared to baseline study. Initial increase in FA values was observed on moving from 0 hour to 1 day in CC and Ctx followed by a sharp decrease in FA on 3rd and 5th day. No abnormalities were visible on anatomical images. Our results suggest the radiation-induced hypoxic changes in brain parenchyma during acute phase even before conventional MRI.