Purpose: To report a case of breast cancer with metastasis to the orbital apex with manifestation of superior divisional third nerve palsy.
Case description: A 40-year-old female, a known case of breast cancer diagnosed 3 years ago, referred to our neuro-ophthalmology clinic with chief complaint of ptosis and diplopia. In ophthalmic examination, visual acuities of both eyes were 20/20 and there was no significant finding in the anterior and posterior segment ophthalmic examination. There was left eye ptosis with MRD1 of 2 mm. In ocular movement examination, there was limitation of motion in supraduction (-2 to -3) of the left eye. Orbital MRI with contrast was requested for the patient which demonstrated a lesion in the orbital apex of the left eye. At the end, the patient was diagnosed as having superior divisional third nerve palsy. Orbital radiotherapy was recommended for the patient.
Conclusion: In a patient with breast cancer who presents with diplopia, metastasis to the orbital apex with manifestation of divisional third nerve palsy should be kept in mind, and appropriate orbital imaging should be considered.
Keywords: Breast cancer; orbital apex metastasis; superior divisional third nerve palsy; third nerve palsy.