Lateral Globe Exposure Associated With Graves Upper Eyelid Retraction: The Influence of the Superior Complex...

To investigate the association of the lateral exposure of the globe with proptosis and the enlargement of the superior complex (SC) (levator palpebrae superioris muscle + superior rectus muscle) in patients with Graves upper eyelid retraction.

Twenty-eight patients with upper lid retraction secondary to Graves orbitopathy and 28 controls matched by age and gender participated in the study. The variables exophthalmometry, margin-reflex distance 1, and upper lid fissure temporal and nasal areas were assessed. Coronal CT scans were evaluated for the measurement of the SC area. A 5% level of significance was assumed for analysis.

Abnormal temporal nasal area differences (T-N), defined as values above the superior limit of the control distribution (15.58 mm 2 ) were detected in 18 patients. Multiple regression analysis showed a significant correlation of abnormal temporo-nasal asymmetries with the SC area and the proptosis (T-N = -6.7 + 0.62* proptosis + 12.3 SC area, R2 = 0.37; p = 0.003).

The etiology of the enhanced lateral globe exposure is not unifactorial. SC enlargement and, to a lesser extent, proptosis are important factors correlated to lateral globe exposure.