Prospective neuroimaging and neuropsychological evaluation in adults with newly diagnosed focal epilepsy

Abstract

AbstractObjectiveThere are few prospective longitudinal studies in patients with newly diagnosed epilepsy (NDE) despite that this is a key time point to understand the underlying biology of epilepsy and to identify potential interventions and biomarkers for seizure and cognitive outcomes. Here we have performed a prospective combined neuroimaging and neuropsychological study in a cohort of patients with focal NDE and healthy controls.MethodsWe recruited 104 patients with NDE and 45 healthy controls for research-grade 3 Tesla MRI (diagnostic and structural imaging, diffusional kurtosis imaging, resting-state functional MRI, task-based functional MRI), EEG, comprehensive neuropsychological, and blood biomarker investigations. We report here on the baseline clinical, neuroradiological, MRI morphometric, and neuropsychological findings in this cohort.Results38% of patients had unremarkable MRI features, 12% had lesions of known significance in epilepsy, 49% with abnormalities of unknown significance in epilepsy, and 23% with incidental findings. In comparison, 56% of controls had unremarkable MRI features, 7% had lesions of known significance in epilepsy, 33% with abnormalities of unknown significance in epilepsy, and 16% had incidental findings. Patients had a higher incidence of white matter hyperintensities compared to controls. Reduced bihemispheric frontal lobe cortical thickness and thalamic volumes were observed in patients with moderate effect sizes. Patients scored significantly lower on tasks of executive function, processing speed, and visual, delayed, and immediate memory, and significantly higher on depression and anxiety assessments compared to controls. Patient neuropsychological performance was related to various brain morphometric features.SignificancePeople with adult focal NDE have a greater proportion of MRI-positive findings than previously reported. Subtle white matter lesions may represent an important diagnostic criterion and have a pathophysiological basis in focal epilepsy. Morphometric and neuropsychological alterations are present at the point of diagnosis of epilepsy, which suggests that brain and cognitive changes are not exclusively due to the deleterious impact of chronic epilepsy.