Alterations in Brain Morphology by MRI in Adults with NF1

Objective: To explore and characterize alterations in brain morphology by MRI in adults with neurofibromatosis 1 (NF1). Methods: MRI measurements of 29 intracranial structures were obtained for 389 adults with NF1 and 112 age- and sex-matched unaffected control subjects. A subset of NF1 patients (n = 70) was also assessed for clinical severity of NF1 features and neurological problems and received psychometric testing for attention deficiencies and IQ. Brain morphological measurements were compared between NF1 and control subjects, and correlation analyses were performed between principal components of the intracranial measurements and clinical and psychometric features. Results: Four of nine corpus callosum measurements were significantly greater in adults with NF1 than in sex- and age-matched controls. All seven brainstem measurements were significantly greater in adults with NF1 than in controls. No robust correlations were observed between the size of these structures and clinical or neuropsychometric assessments. Conclusions: Our findings are consistent with the hypothesis that dysregulation of brain myelin production is an important manifestation of NF1 in adults.