Blink and You'll Miss It: Diagnostic Pitfalls in a Case of Missed Ocular Myasthenia Gravis in the Emergency Department

Ocular myasthenia gravis (MG), a subtype of MG limited to the eyelids and extraocular muscles, is diagnostically challenging in the emergency department (ED). In the absence of generalized weakness, subtle symptoms such as ptosis and diplopia are more easily overlooked or misattributed to stroke or other neurologic pathologies. We present a case of a 69-year-old male whose diagnosis of ocular MG was delayed due to limited neurologic examination, underuse of simple bedside tools, and incidental imaging findings that initially suggested alternative endocrine pathology. Despite classic signs, including fatigable ptosis and diplopia, treatment with pyridostigmine was not initiated until 31 hours after ED arrival, at which point the patient experienced near-complete resolution of ocular symptoms within one hour. This case highlights the importance of maintaining clinical suspicion for MG in cranial nerve presentations. Incorporating accessible bedside tests, such as the ice pack test or acetylcholinesterase inhibitor trial, can expedite diagnosis and treatment in the ED.