Evaluation of the medial rectus muscle and optic nerve using strain and shear wave elastography in Graves' patients.

Purpose: The purpose of this study was to describe the elastic properties of the medial rectus muscle and optic nerve in Graves' patients without clinically apparent ophthalmopathy using strain elastography (SE) and shear wave elastography (SWE) and to determine whether these elastic properties could be used to aid in the diagnosis of the medial rectus muscle or optic nerve involvement.
Materials and Methods: Thirty participants diagnosed with Graves' disease without ophthalmopathy and 30 healthy volunteers (control group) were prospectively examined between November 2018 and August 2019. SE and SWE findings in both groups were compared using the χ ² test and the independent samples t test.
Results: A statistically significant softening of the medial rectus muscle was observed in the SE patterns of the Graves' patients (p = 0.009). A statistically appreciable distinction was observed between the medial rectus muscle (7.64 ± 2.1 and 9.20 ± 1.7 kPa, p = 0.000) and the optic nerve (8.35 ± 2.8 and 9.37 ± 1.5 kPa, p = 0.019) in the SWE modulus of the Graves' patients and healthy volunteers.
Conclusion: SE and SWE can be used to identify structural alterations to the medial rectus muscle and optic nerve before clinically apparent Graves' ophthalmopathy has developed.