Predictive Factor for Therapeutic Results after Intravenous Glucocorticoid Therapy in Thyroid-Associated Ophthalmopathy

Yim, Ji Hye; Kim, Won Bae; Kim, Eui Young; Kim, Won Gu; Kim, Tae Yong; Shong, Young Kee

Abstract

BACKGROUND AND OBJECTIVES
Little has been known for factors predicting improvement of proptosis in patients with thyroid-associated ophthalmopathy (TAO) after intravenous (IV) glucocorticoid therapy. This study aimed to evaluate the efficacy of IV glucocorticoid therapy and to find factor predicting treatment outcomes in patients with TAO.
MATERIALS AND METHODS
Forty-two consecutive patients with TAO treated by IV glucocorticoid from 2000 to 2009 were retrospectively analyzed. They received IV methylprednisolone of 7.0 g over 18 weeks. Before and after treatment, patients underwent orbital CT for assessment of proptosis and extraocular muscle hypertrophy, and physical examination for clinical activity score (CAS).
RESULTS
Thirteen patients (31%) showed improvement in proptosis after therapy. High extraocular muscle diameter index was an independent predictor for improvement in proptosis (odds ratio=1.25, p=0.03). Smoking, age, gender and initial CAS did not predict improvement. Seven of 16 patients with initial CAS<3 (43%) and 13 of 17 with initial CAS> or =3 (77%) showed improvement in diplopia after treatment (p=0.002). Of patients with CAS> or =3, patients with intermittent, inconstant and constant diplopia showed improvement in diplopia in 100%, 80% and 63%, respectively. Of patients with CAS<3, patients showed improvement in 80%, 33% and 20%, respectively.
CONCLUSION
Presence of extraocular muscle hypertrophy was the only factor predicting improvement in proptosis after IV glucocorticoid therapy. In patients with TAO, IV glucocorticoid therapy could be considered to improve proptosis when they present with increased extraocular muscle diameter, or to improve diplopia especially when they also have high initial CAS.