Exophthalmos of patients with Graves' disease in Chinese of Taiwan

Purpose To determine the exophthalmos measurements in patients with Graves' disease (GD) and to compare with those of normal subjects among the Chinese of Taiwan. Methods Hertel's exophthalmometry were performed in 163 consecutive adult GD patients and 419 normal subjects. The values of exophthalmos, asymmetry, and the distance between lateral orbital rims ( base) were evaluated. Results There was a significant difference between GD and normal adults for exophthalmos and asymmetry, with GD patients demonstrating a mean exophthalmos of 18.32mm and asymmetry of 0.93mm as compared with 13.91 and 0.55mm for normal subjects (P < 0.001). The mean value of base for GD adults (106.52 mm) is slightly greater than normal subjects (105.82 mm). There was no gender difference in exophthalmometric value or asymmetry in each group. A total of 79 (48.5%) GD patients had exophthalmos greater than the upper limit of normal Chinese in Taiwan (18.6 mm). Asymmetry over 2mm was observed in 11 (6.7%) patients with GD but in none of the normal subjects. Conclusions GD patients have significant exophthalmos and asymmetry compared to normal subjects. In comparison with previous studies, exophthalmos values for Chinese in Taiwan tend to be lower than those of Caucasians and black-American people, but are close to those of Korean, Japanese, Iranian, Indian, and Asian-American people. Adequate adjustment of normal and abnormal values of exophthalmos according to individual differences is important for the diagnosis of orbital morbidity and management of thyroid associated orbitopathy.