Functional and Morphological Brain Alterations in Dysthyroid Optic Neuropathy: A Combined Resting-State fMRI and Voxel-Based Morphometry Study

BackgroundIncreasing evidence has indicated that the entire visual pathway from retina to visual cortex may be involved in dysthyroid optic neuropathy (DON) pathological mechanisms.PurposeTo explore the functional and morphological brain characteristics in DON and their relationship with ophthalmologic performance.Study TypeRetrospective.PopulationA total of 30 DON patients, 40 thyroid-associated ophthalmopathy (TAO) without DON patients and 21 healthy-controls (HCs).Field Strength/SequenceA 3.0 T, 3D T1-weighted spoiled gradient-recalled echo and gradient-recalled echo-planar imaging.AssessmentFunctional and structural alterations in brain regions were evaluated with fractional amplitude of low-frequency fluctuations, degree centrality (DC), and gray matter volume (GMV). Clinical activity score (CAS) is assessed across patients.Statistical TestOne-way analysis of variance with post hoc two sample t-tests (GRF-corrected, voxel level: P < 0.005, cluster level: P < 0.05) and correlation analysis (significance level: P < 0.05).ResultsCompared to HCs, DON patients had significantly decreased DC values in the bilateral BA17 and BA18 regions. Compared to the TAO group, DON patients had decreased GMV in the left anterior cingulate cortex, left middle frontal gyrus, left lingual gyrus, left parietal gyrus, right Rolandic operculum, left supplementary motor area, and right middle temporal gyrus. In addition, GMV in the right Rolandic operculum was significantly positively correlated with CAS (correlation coefficient: r = 0.448).Data ConclusionThis study showed significant morphological and functional alterations in visual cortex and morphological alterations in partial default mode network regions of DON patients, which may provide insights into the mechanism of vision loss and may facilitate the diagnosis and treatment of DON.Evidence Level3.Technical EfficacyStage 3.

Automated summary

This study explored the brain characteristics and their relationship with ophthalmologic performance in patients with dysthyroid optic neuropathy (DON). The results showed significant morphological and functional alterations in the visual cortex of DON patients, which may provide insights into the mechanism of vision loss and facilitate the diagnosis and treatment of DON.