PMC10064162_01
Continuous electroencephalography (cEEG) recording 24 h post-hospitalisation. Periodic epileptiform discharges are evident (red continuous arrow shows spike and red dotted arrow shows spike and wave). A monopolar montage was performed using 17 subcutaneously monopolar stainless steel disposable needle (length 12 mm; diameter 0.32 mm). The nomenclature for the positioning of the electrodes was in accordance with that described for the 10-20 international system of human electroencephalography (EEG), with odd numbers denoting the left side electrodes and even numbers for right side electrodes. The letter 'Z' defines the midline. The electrodes were positioned according to the following arrangement: frontal (F8, F4, Fz, F3 and F7); temporal (T6, T4, T5 and T3); parietal (P4, P3 and Pz); central (C4, C3 and Cz); and occipital (O1 and O2). The ground electrode was placed caudal to the occipital protuberance, while the reference electrode was placed on the bridge of the nose. Recording parameters included a time constant of 0.1 s and a high frequency filter set at 30 Hz; sensitivity was 2 microV/mm. A 50 Hz notch filter was used. Impedances below 5 kOmega were measured for all electrodes before performing cEEG
10.1177_20551169231160228-fig1.jpg
PMC10064162_01_10.1177_20551169231160228-fig1.jpg
fig1-20551169231160228
At 24 h post-hospitalisation, a first cEEG (EBNeuro) was carried out for 1 h and 5 mins, which showed paroxysmal epileptiform discharges (PEDs) such as spikes, mainly at the level of the right cerebral cortex (Figure 1).
Continuous electroencephalography recording during the second day. Burst suppression pattern characterised by beta and theta waves interspersed to period of isoelectric activity lasting a few seconds are present
10.1177_20551169231160228-fig2.jpg
PMC10064162_01_10.1177_20551169231160228-fig2.jpg
fig2-20551169231160228
A second cEEG was performed 48 h post-hospitalisation, showing the presence of rare spikes and a burst-suppression pattern (BSP; Figure 2).
Continuous electroencephalography recording 72 h post-hospitalisation. No pathological changes were found during 3 h of recording
10.1177_20551169231160228-fig3.jpg
PMC10064162_01_10.1177_20551169231160228-fig3.jpg
fig3-20551169231160228
At 72 h post-hospitalisation, a third cEEG showed normal cerebral activity and no spikes or BSP were detected (Figure 3).