Fig. 3.

Case 1. (A) Computed tomographic scan at the onset of stroke reveals left huge putaminal hematoma with intraventricular hemorrhage. (B) At postoperative 1 year (interictal state), MR images with fluid attenuated inversion recovery (FLAIR) demonstrate a huge old hematoma cavity, surrounded by gliosis, in the left putamen extending to the left fronto-parietal and temporal lobes. (C) On ASL with a PLD of 1.5 s, markedly decreased ASL signals are noted in the extended area of the left hemisphere.

(D) At the first ictus, ASL with a PLD of 1.5 s, which is performed approximately 3 h after the secondary generalized seizure for 3 min, fails to reveal ictal hyperperfusion. (E) On subsequent EEG, continuous slow wave activities are noted on the left hemisphere, while breach rhythm appears on the right hemisphere due to left large craniotomy.

(F) ASL with a PLD of 1.5 s, which is performed approximately 18 h after the second epileptic ictus for 30 min, ASL signals in the left hemisphere except for old hematoma cavity (white dotted arrows), especially in the temporal lobe (white arrow), are increased compared with those of the interictal state. On the contrary, ASL signals on the right side, especially the right temporal lobe, are decreased. (G) Subsequent EEG shows continuous slow wave activities on the left hemisphere with interictal paroxysmal activities on the left temporal region (F7 & T3 of the International EEG 10–20 system, black arrows).

(H) ASL with a PLD of 1.5 s, which is performed within 1 h after the third epileptic ictus for 1 h, depicts a marked increase of ASL signals in the cortex of the left hemisphere, except for a surgical defect. (I) DWI shows cortical hyperintensity in the corresponding area to that of the ictal hyperperfusion on ASL (white arrows). (J) Subsequent EEG shows continuous slow wave activities on the left hemisphere with interictal paroxysmal activities on the left temporal region (black arrows).