PMC9345586_01
Neuroimaging studies of the case. (A) Head computed tomography scan showing diffuse subarachnoid hemorrhage with intraventricular hemorrhage and hydrocephalus; (B) computed tomography angiogram showing a right supraclinoid internal carotid artery aneurysm; (C) FLAIR magnetic resonance imaging and (D) diffusion magnetic resonance imaging show no abnormalities.
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Computed tomography (CT) showed diffuse SAH, mild intraventricular hemorrhage and hydrocephalus (Figure 1A). A CT angiogram showed a right supraclinoid internal carotid artery aneurysm (Figure 1B). Magnetic resonance imaging (MRI) did not detect abnormalities (Figure 1C and 1D).
Electroencephalography of the case. (A) Standard encephalography on Day 6; (B) Standard encephalography on Day 12.
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GPD pattern with frontal predominance as a continuous periodic discharge pattern with triphasic morphology and no spontaneous fluctuation, as seen in toxic and/or metabolic brain dysfunctions (Figure 2A). Given these findings, the VPA dosage was 65.3microg/mL (therapeutic range: 50 - 100microg/mL), and the ammonium dosage was 160.2microg/mL (normal range: 18.7 - 86.0microg/mL). Subsequent EEGs progressively improved until normal (Figure 2B).