Abnormal apparent diffusion coefficient of ultra-high b-values in the bilateral thalamus and striatum in MRI-negative refractory epilepsy

Motivation: Subcortical nuclei such as the thalamus and striatum have been shown to be related to seizure modulation and termination, especially in refractory epilepsy. Goal(s): This study aimed to assess AQP4 function reflected by the apparent diffusion coefficient (ADC) from ultra-high b-values (ADCuh) in MRI-negative refractory epilepsy. Approach: The eDWI parameters such as standard ADC (ADCst), pure water diffusion (D) and ADCuh were calculated from the 15 b-values. Results: ADCuh values in the bilateral thalamus, caudate nucleus, putamen and globus pallidus in MRI-negative refractory epilepsy were significantly higher than those in the healthy control subjects. Impact: The alterations of the ADCuh values in the bilateral thalamus and striatum may reflect abnormal AQP4 function in MRI-negative refractory epilepsy. ADCuh might be a useful measurement for evaluating subcortical nuclei related brain damage in epilepsy patients.