Figure 1: (a) Symmetric blood volume demonstrated on CT perfusion scan, in a 79-year-old woman presenting with a classic left MCA syndrome. (b) The absence of a proximal vessel cut-off in a CT angiogram reconstruction of the circle of Willis. (c) The absence of restricted diffusion in an MRI brain. (d) The absence of FLAIR hyperintensities indicative of an acute ischemic stroke or herpes simplex encephalitis. (e) Left anterior and midtemporal periodic lateralized discharges seen on hospital day 2, with a notable background which is diffusely slow, and an absence of a posterior dominant rhythm (PDR). (f) Return of the PDR of 8-9 Hz and the absence of PLEDs after the institution of intravenous valproic acid and acyclovir therapy.