This episode explores the predictive value of preoperative brain microstructural alterations for the success of microvascular decompression (MVD) in classical trigeminal neuralgia (CTN). Based on an abstract from 'Cephalalgia : an international journal of headache' (2026), this study analyzed white and gray matter changes using Neurite Orientation Dispersion and Density Imaging (NODDI) in CTN patients and healthy controls. Key findings revealed widespread microstructural disruptions in CTN patients, with preoperative free-water accumulation in a specific gray matter cluster emerging as a highly specific predictor of MVD failure. These insights have significant clinical implications for personalizing treatment strategies and managing patient expectations. This information is for educational purposes and not a substitute for professional medical advice.