Voxel-Based Morphometric Features of Dysthyroid Optic Neuropathy

Abstract

Background: Dysthyroid optic neuropathy (DON) is a serious complication of thyroid-associated ophthalmology (TAO), leading to loss of vision or blindness. Numerous studies had reported thyroid dysfunction affects a wide range of visual pathways in adults, from the retina to the visual center. We aimed to explore if there were abnormalities of gray matter density (GMD) in DON patients.Methods: We collected patients with TAO from The Eye Hospital of Wenzhou Medical University. All patients underwent routine ophthalmic examination, Clinical Activity Score (CAS), intraocular pressure (IOP), exophthalmos, visual field, OCT,and orbital CT scan. 16 patients with DON and 16 patients without DON (N-DON) were enrolled in this study. Age, gender, orbital congestion index and degree of education of patients were matched between the two groups. High-resolution magnetization-prepared rapid acquisition with gradient echo (MPRAGE) scans was performed on all patients. Voxel-based morphometry (VBM) was applied to analyze the T1 weighted images of the brain, based on functional magnetic resonance imaging (FMRI) integrated VBM (FSL-VBM).Results: GDM was significantly decreased in the right middle temporal gyrus, left middle frontal gyrus, left superior frontal gyrus, and right middle frontal orbicular gyrus in the DON when compared to N-DON.Conclusions: The DON can result in reduced GMD in specific areas of the brain. This finding suggests that there may be other mechanisms in Don