ABSTRACT
A 47-year-old male presents to the local ophthalmology office complaining of diplopia. It is worse in the evening, and gets worse with reading. The left eyelid is droopy later in the day as well. On examination the visual acuity is 20/20 in each eye. External photograph and motility are shown below (Figures 15.1 and 15.2). He has significant ptosis of the left upper lid, and mild ptosis on the right. He has a Cogan’s lid twitch sign. He is given a Fresnel prism which alleviates the diplopia. Prostigmine testing was positive. Serum antiacetylcholine receptor antibodies come back and are all strongly positive (blocking, binding, modifying) suggesting a diagnosis of myasthenia gravis. When he is called back to discuss the results of the testing, he asks if any other parts of the body can be affected by this disease in the same way as his eye movements and eyelids and if anything can be done to prevent generalized disease
PRO: STEROIDS MAY PREVENT GENERALIZED MYASTHENIA GRAVIS IN PATIENTS PRESENTING WITH AN ISOLATED OCULAR FORM OF THE DISEASE
Nicholas Volpe The ophthalmologist and neuroophthalmologist are frequently on the front lines of the diagnosis of myasthenia gravis. A significant percentage of patients with myasthenia gravis will present with isolated ocular symptoms and these patients will present to the neuroophthalmologist with complaints of either ptosis and/or double vision. Between 30 and 50% of patients with ocular myasthenia gravis (OMG) will go on to develop generalized disease, most with 2 years of onset of ocular symptoms. Like the patient presented, the diagnosis of ocular myasthenia is easily made on the clinical exam based on the presence of variable, fatigueable ptosis, with Cogan’s eyelid twitch and/ or orbicularis weakness and is further supported by variable pattern of eye movement abnormalities, which changes and/or fatigues during the course of the exam.
