A Case of Ocular Myasthenia Gravis with Thytmolipoma and Thymic Cyst

ABSTRACT

The incidence of thymolipoma or thynuc cyst is very rare among the tumors of thymic origin, which are usually benign or invasive thymoma. Thymic tumor has been found among 10 to 15% of the patients with myasthenia gravis(MG). However the patients with thymolipoma or thynuc cyst rarely manifestated as MG. Moreover the case of MG with thymolipoma and thymic cyst is extremely rare ; Only one case has been reported hitherto. We hereby report a 41-year-old woman presenting as ocular MG with thymolipoma and thymic cyst. She complained diplopia, ptosis and headache, which had begun 3 months prior to admission and have been fluctuating thereafter. Ocular MG was confirmed by positive Tensilon and Jolly test. Her chest CT showed an enlarged thymus which turned out to be thymolipoma with thymic cyst on the pathologic examination. Although rare, thymolipoma and/or thymic cyst should be considered in the differential diagnosis of thymic tumor in MG.