Study Objectives: Neuroimaging studies on structural alterations in patients with type 1 narcolepsy (NT1) have shown controversial and heterogeneous results. The purpose of this study was to investigate microstructural brain changes in patients with NT1 close to disease onset.
Methods: We examined cortical and subcortical grey matter volumes in 20 drug-naïve children and adolescents with NT1 compared with 19 healthy controls; whole-brain voxel-based morphometry, shape and volumetric analyses, and cortical thickness analysis were used.
Results: When compared with controls, NT1 patients revealed reduced grey matter volume in cerebellum and medial prefrontal cortex and increased volume in right hippocampus. Cortical thickness in frontal lobe was also reduced in patients compared with controls. Increased volume and shape expansion in right hippocampus in patients compared with controls were also confirmed by both vertex and volumetric analyses.
Conclusions: Our results indicate that subtle structural brain changes involving attentional and limbic circuits are detectable in children and adolescents with NT1. Cerebellum involvement might be related to the childhood NT1 clinical phenotype.