Ocular movement disorders and extraocular muscle involvement in Iranian Graves' ophthalmopathy patients

Purpose: The aim of this study was to evaluate movement disorder patterns and extraocular muscle involvement in Iranian Graves' ophthalmopathy (GO) patients. Methods: We examined 75 patients (37 women and 38 men) with GO. Female to male ratio was 0.97 among all patients and 0.72 among restrictive myopathic cases (male 18 (58.1%), female 13 (41.9%), P=0.2). Their age ranged from 16 to 66 years; mean age was 35.42+/-11.63 and 33.55 +/-10.31 among patients affected by restrictive enlargement and whom did not, respectively. Results: Orbital CT assessment showed EOM enlargement in 124 out of 150 orbits (82.6%). Clinical restriction was evident in 31 (41.3%) out of 75 patients. Bilateral restriction was observed in 14 out of 31 (45.1%). The most frequent type of movement limitation was supraduction limitation followed by abduction, inferaduction, and adduction limitations (59%, 40% , 31.1% and 13.3% respectively). This was compatible with Hess screen results and orbital CT reports in regard of IR, MR , SR, and LR involvement. Sixteen out of 75 patients reported diplopia. Mean Hertel exophthalmometry readings were higher in eyes with restrictive myopathy. Conclusion: This study showed more restrictive myopathy in cases with more extraocular enlargement and positive correlation between severity of inferior rectus enlargement and Hertel reading. A higher rate of male patients in our study may be due to ethnic differences in GO in Iranian patients or due to severity of involvement in this group.