Review Question - QID 210628

A 32-year-old woman is referred to a neurologist for a headache. Her headaches began a few weeks ago, and she describes them as throbbing and occurring on one side of the head. She also experiences pain with eye movement. Her headaches are frequent, occur daily, and appear to worsen when she changes posture and improves when she rests and takes ibuprofen. Her headaches are accompanied by nausea, vomiting, tinnitus, and transient visual obscurations with brief sparkles of light. These visual symptoms occur a few times a week and last a few seconds. Standing from a seated position seems to trigger these visual symptoms. Medical history is significant for migraine headaches, obesity, hypertension, and breast cancer which is in complete remission. Her temperature is 98.7°F (37°C), blood pressure is 135/83 mmHg, pulse is 73/min, respirations are 14/min, and oxygen saturation is 99% on room air. Neurological examination is remarkable for visual field loss on confrontation and a left abducens nerve palsy. The funduscopic exam is demonstrated in Figure A, and an MRI of the brain is shown in Figure B. Which of the following is the most appropriate initial step in management?