Radiological Activity Score (RAS)-MRI Characteristics in Dysthyroid Optic Neuropathy in a Multi-Ethnic Thyroid Eye...

Area of Science:

• Ophthalmology
• Radiology
• Endocrinology

Background:

• Dysthyroid Optic Neuropathy (DON) is a sight-threatening complication of Thyroid Eye Disease (TED).
• Accurate diagnosis of DON is challenging.
• MRI offers potential for diagnostic insights.

Purpose of the Study:

• To compare MRI features in patients with and without DON.
• To identify MRI indicators associated with a higher likelihood of DON.

Main Methods:

• Retrospective cohort study of TED patients over eleven years.
• Analysis of Axial T1-weighted, coronal STIR, and DWI MRI sequences.
• Assessment of apical crowding (AC), extraocular muscle (EOM) enlargement, peri-muscular fat (PMF)/muscle signal intensity (SI), and Apparent Diffusion Coefficient (ADC) values.

Main Results:

• DON group showed significantly higher EOMSI, PMFSI, EOME, and AC compared to non-DON.
• Average ADC values were significantly higher in the DON cohort (1373 ± 319) versus non-DON (973 ± 237).
• Apical crowding (OR 22.1) and ADC value ≥ 1200 (OR 3.7) were significant predictors of DON on multivariable analysis.

Conclusions:

• Significant apical crowding and elevated ADC values are associated with a higher diagnostic likelihood of DON.
• ADC values show promise in diagnosing and predicting DON.
• MRI features can aid in differentiating DON from other TED complications.