Changes in the position of the eyeball in TAO patients with unilateral upper eyelid retraction by T2-weighted SPIR imaging

For patients with thyroid-associated orbitopathy (TAO) presenting unilateral upper eyelid retraction, the phenomenon that the impaired eye is lower than the healthy eye (“eyeball descending”) has been noticed. This study investigated the eyeballs' position changes by 3D reconstitution of magnetic resonance (MR) images. With reference to the central plane of the healthy side, 70.37% impaired eyeballs (19/27) were found in significantly lower positions, and with significant positive correlations of increased thicknesses of levator palpebrae superioris (LPS), superior rectus (SR), and LPS-SR complex volume. This study provided objective evidence of “eyeball descending” in unilateral upper eyelid retraction TAO patients.