Check Your Assumptions at the Door

A 74-year-old female with metastatic carcinoid tumor presented with acute painless vision loss in the right eye. In the four weeks preceding vision loss she had episodic diplopia. Over the past few days, she noticed a gray shade coming down over her right eye. Her carcinoid tumor was diagnosed in 2019 with brain metastases identified in 2021. She had undergone whole brain radiation and treatment with ipilimumab and nivolumab. Her current medications were nivolumab, gabapentin, and omeprazole. Visual acuity was 20/40 and 20/25 in the right and left eyes, respectively.