Bilateral Disc Edema Masquerade Primary angiitis of the central nervous system

A 58-year-old man with a history of hypertensive retinopathy presented with acute-onset, painless vision loss in his right eye accompanied by tinnitus and severe intermittent headaches. Fundus examination was remarkable for pallor of both optic nerves, more notably in the right eye, without edema. What would you do next?