White-matter alterations in dysthyroid optic neuropathy: a diffusion kurtosis imaging study using tract-based spatial...

Area of Science:

• Neuroimaging
• Ophthalmology
• Neurology

Background:

• Dysthyroid optic neuropathy (DON) lacks a definitive diagnostic standard.
• Thyroid-associated ophthalmopathy (TAO) can lead to vision-threatening complications like DON.
• Diffusion kurtosis imaging (DKI) offers potential for identifying imaging biomarkers.

Purpose of the Study:

• To investigate white matter (WM) alterations in TAO patients with and without DON using DKI.
• To explore the diagnostic utility of DKI parameters for differentiating DON.
• To correlate DKI findings with clinical variables.

Main Methods:

• A cross-sectional study involving 53 TAO patients (21 DON, 32 non-DON) and 30 healthy controls (HCs).
• Diffusion kurtosis imaging (DKI) data analyzed using tract-based spatial statistics.
• Receiver-operating characteristic (ROC) curve analysis to assess diagnostic performance.

Main Results:

• Both DON and non-DON groups showed reduced kurtosis and fractional anisotropy in WM compared to HCs.
• DON patients exhibited lower radial kurtosis (RK), mean kurtosis (MK), and axial kurtosis (AK) than non-DON patients, primarily in visual pathways.
• RK values in the posterior thalamic radiation (PTR) correlated with visual acuity and showed diagnostic potential for DON.

Conclusions:

• WM microstructural abnormalities, especially in the visual system, are evident in DON.
• DKI may offer insights into DON's neural mechanisms.
• DKI shows promise for timely DON diagnosis and guiding neuroprotective therapies.