Clinical analysis of ocular myasthenia gravis

Abstract

Objective To study clinical characteristics of ocular myasthenia gravis (OMG) to provide evidence for diagnosis and treatment of this disease. Methods Clinical data of 113 OMG patients were retrospectively analysed. Immunofluoresence cell staining was applied to detect the acetylcholine receptor (AChR) antibody and muscle ⁃ specific receptor tyrosine kinase (MuSK) antibody, and their predictive value for developing to generalized myasthenia gravis (MG) was assessed. Results Adult⁃onset of OMG was often happened in males over age 40. The most common initial presentation was ptosis (n = 95, 84.07% ), and a few started with diplopia (n = 18, 15.93% ). The positive ratio of fatigue test and neostigmine test was 79.44% (85/107) and 84.85% (84/99) respectively, abnormal rate of repetitive nerve stimulation (RNS) and serum thyroid antibodies was 44.32% (39/88) and 28% (14/50) respectively. The incidence of thymic hyperplasia and thymoma was 16.67% (17/102) and 11.76% (12/102), respectively. The positive rate of serum AChR antibody was 62.83% (71/113), but the serum MuSK antibody was negative in all patients. There were 12.39% (14/113) OMG patients progressed to generalized MG. Patients with higher AChR antibody expression were with more risk to progress to generalized MG (χ2 = 4.587, P = 0.032). Conclusion Adult ⁃ onset OMG often begins in middle ⁃ aged males. The main manifestation of OMG are ptosis and diplopia. Most patients are associated with abnormality of thymus and thyroid. Patients with higher AChR antibody expression are more at risk for progressing to generalized MG. MuSK antibody is uncommon in OMG. DOI：10.3969/j.issn.1672-6731.2011.01.018