Abstract
Abstract: :
Purpose: To analyze whether those cases with combined Ocular Myasthenia Gravis (OMG) and Graves Disease have a different frequency of developing Generalized Myasthenia (GMG) than do those without Graves. Methods: Retrospective chart review. Results: We reviewed the charts of patients who presented to our department with Graves Ophthalmopathy who subsequently developed Myasthenia Gravis (MG). The patients were diagnosed with Graves Disease prior to (up to 5 years) or at the time of being diagnosed with OMG, which remained purely ocular in all cases. The follow-up from onset of OMG ranged from 2 years to 4.75 years. Conclusion: Myasthenia Gravis is an immunologic disorder mediated by autoantibodies directed against post-synaptic membrane receptors, and is known to be associated with other autoimmune disorders. It exists in two forms, OMG and GMG. Half of all myasthenics present with ocular signs, 90% of MG cases will have ocular signs in their course. Of those who present with OMG, 50% will develop signs consistent with the generalized form of myasthenia.Graves disease is also mediated via autoantibodies and may share certain immunologic factors (e.g. HLA) with Myasthenia Gravis. It is well documented that Graves disease is seen in 5% of MG patients and MG is seen in 0.2% of Graves's patients. It is known that of the 80% of OMG patients who convert to GMG, ≷90% do so within two years. Whether there is a differential risk of generalizing in patients with isolated OMG versus those with Graves Disease and OMG has, to our knowledge, never been investigated. We present a series of patients with Graves Disease who have purely the ocular form of myasthenia. Although the series is limited in size, none of our patients with OMG and Graves have gone on to develop the general form of the disease, indicating that there might be a different immunologic substrate to the form of OMG associated with Graves than to that form not associated with Graves. This preliminary data suggests a larger multi-institution study is warranted to investigate this hypothesis. Supported by: Research to Prevent Blindness, Inc., The NJ Lions Eye Research Foundation, The Eye Institute of New Jersey.
Keywords: 327 autoimmune disease • 486 neuro-ophthalmology: diagnosis • 355 clinical (human) or epidemiologic studies: risk factor assessment