Bilateral metastases to the extraocular muscles from small cell lung carcinoma.

Bilateral orbital metastases restricted to the extraocular muscles (EOMs) are exceedingly rare. We report a case of bilateral extraocular muscle metastases from a small cell lung carcinoma and provide a review of the relevant literature. A 56-year-old smoker presented with proptosis, motility changes, and a relative afferent pupillary defect of the left eye, with a previous history of a small cell lung carcinoma. An orbital computerized tomography scan revealed a mass restricted to the left medial rectus. An incisional biopsy confirmed metastasis. Visual acuity of the left eye decreased rapidly, and right globe proptosis became evident. Orbital magnetic resonance imaging at two months follow-up showed marked left orbital mass enlargement and a new right lateral rectus mass. The patient was maintained on palliative care and died from metastatic disease-related complications.