Figure 1.

The methods for measurements of EOM-SIR and IF-WF. Coronal Fat-sat T ₂WI (a) and two-point Dixon T ₂WI of water-only (b) and fat-only (c) in a 32-year-old female with active TAO. For the quantitative measurement of EOM-SIR (a, b), a circular ROI (yellow, 5–10 mm²) was placed in the area of the most inflamed muscle with the highest signal intensity observed by naked eye and in ipsilateral temporal muscle, respectively. For the quantitative measurement of IF-WF (b, c), a circular ROI (red, 5–10 mm²) was placed in the area of intraorbital fat. EOM, Extraocular muscle; fat-sat, fat saturation; IF, intraorbital fat; ROI, region of interest; SIR, signal intensity ratio; T ₂WI, T ₂ weighted; TAO, thyroid-associated ophthalmopathy; WF, Water fraction.