Fig. 1
From: Brain MR findings in patients treated with particle therapy for skull base tumors
MRI performed 16 months after carbon ion therapy of a sino-nasal adenoid-cystic carcinoma. T2-weighted image (a) shows an extensive area of altered signal intensity involving right gyrus rectus, polar and mesial temporal regions. Axial postcontrast T1-weighted image (b) shows two different areas of enhancement: a focal area of enhancement without necrosis, surrounded by edema, as a grade 1 injury of Late Effects Normal Tissue Task Force subjective, objective, management and analytic (LENT-SOMA) scoring system in right mesial temporal region (yellow arrowhead); a larger area with non-enhancing portion of necrotic tissue with peripheral rim enhancement, surrounded by edema, in right gyrus rectus. The axial diffusion weighted (DWI) image (c) and apparent diffusion coefficient (ADC) map (d) show no diffusion restriction within the enhancing area with an evident hyperintense area in ADC map. Cerebral blood flow (CBF) (e) and relative cerebral blood volume (rCBV) (f) maps show no hyperperfusion in the enhancing area. Magnetic resonance spectroscopy (MRS)-short TE (g) reveals the presence of high lipid and lactate peaks, which is typical of radiation necrosis