Orbital Metastasis Secondary to Breast Cancer: A Rare Cause of Unilateral External Ophthalmoplegia.

Orbital metastases are rare causes of orbital tumours, and may present with pain, photophobia, red eye, vision loss, diplopia, proptosis, or external ophthalmoplegia. Breast cancer is responsible for a great majority of orbital metastases. Herein, we report a 78-year-old female who had unilateral external ophthalmoplegia due to orbital metastasis of primary breast cancer.