Ocular Myasthenia Gravis As Unilateral Ptosis and External Ophthalmoplegia: A Case Report

Myasthenia gravis (MG) is an autoimmune disorder characterized by fluctuating weakness and fatigue in ocular, bulbar, limb, or respiratory muscles. Initially, more than half of MG patients experience isolated ocular symptoms, such as ptosis, diplopia, or muscle paresis. This case report presents a unique occurrence of MG in a four-year-old female, showcasing a two-year history of sudden onset, persistent yet fluctuating unilateral ptosis accompanied by exo-deviation and adduction deficit in the right eye. No diplopia or systemic features were observed. Positive findings in tests, including the ice pack test, Cogan twitch sign, fatiguability, and neostigmine test, indicated ocular myasthenia. Electromyography revealed a decremental response, while anti-acetylcholine antibodies showed borderline results. Computed tomography of the brain ruled out central causes, and routine laboratory testing yielded normal results. Treatment with pyridostigmine and corticosteroids led to significant improvement in symptoms. This case emphasizes the diverse presentation of MG in ophthalmology, with ocular signs serving as indicators in approximately half of the cases. Early diagnosis and prompt treatment are crucial for enhancing long-term prognosis. Emergency physicians should consider MG as a potential cause for unilateral ocular symptoms after excluding central causes. Accurate diagnosis and comprehensive management of MG are complex yet essential for ensuring optimal patient health.