Sorry! There are a few reasons why this shouldn't be the very next step. With such a neurologic decline, we're still considering things like cerebral vasoconstriction or even increased ICP, so we shouldn't send the patient down for an hours-long scan. If we end up seeing vasoconstriction in a territory that would explain her deficits, then treatment with an intraarterial vasodilator could be pursued, admitting that it's unclear if this would affect long-term outcomes. While it's less likely, we still have a duty to rule out an aneurysmal etiology. (It's reassuring that the hematoma burden was stable on repeat NCHCT. It's likely too early for vasospasm if this was indeed an aneurysmal SAH, unless we were totally off about the symptom onset.) It's true that if we're most suspecting PRES, then an MRI would be the most diagnostic. We can still pursue that later once we've taken care of this higher priority.