Fig. 4

Continuous VEEG presentation before and after plasma exchange. a Video electroencephalography (VEEG) presentation before plasma exchange 6 weeks after admission. The patient showed recurrent sweating profusely on the right forehead and enlargement of the right pupil. Continuous VEEG showed paroxysmal slow waves, especially 0.5–1 Hz/s slow waves, alternating with low voltage with no reactivity. b VEEG presentation after plasma exchange. After 3 times of plasma exchange, VEEG showed alpha rhythm and the patient recovered consciousness