Changes in cerebral hemodynamics during a sleep-deprived video-electroencephalogram in healthy children

Neuropsychological Deficits in Patients with Electrical Status Epilepticus During Sleep: A Non-invasive Analysis of Neurovascular Coupling

To evaluate the effects of electrical status epilepticus during sleep (ESES) on cerebral blood flow (CBF) and explore the associated neuro-vascular coupling and neuropsychological deficits. 19 ESES patients were recruited to undergo real-time transcranial doppler ultrasonography (TCD) and video-EEG monitoring (vEEG). Patients were grouped based on their cognitive functions or their EEG patterns. The mean cerebral blood flow velocity (CBFV_m) of the unilateral middle cerebral artery was measured using TCD and was used to calculate various relevant parameters. The 19 patients participated in a total of 54 effective TCD-vEEG monitoring sessions. We found a significant effect of clinical severity for the following measurements: spike wave index (SWI), peak and average deep sleep stage (N3) CBFV_m, peak, average and minimum deep sleep and awake CBFV_m, and CBFV_m oscillations during deep sleep. Nevertheless, CBFV_m oscillations were not related to SWI. Furthermore, CBFV_m oscillations revealed a statistically significant difference between the near-ESES and asymmetric-ESES groups. CBFV_m oscillations may reflect the neuro-vascular coupling process associated with ESES disfunction. Understanding the relationship between CBFV_m oscillations and epileptic activity will be important for assessing the neuropsychological damage associated with ESES and for developing treatment options for this and other diseases.

Acquired epileptiform opercular syndrome evaluated with real-time transcranial Doppler ultrasound-video-electroencephalogram before and after treatment: a case report

Background

Acquired epileptiform opercular syndrome (AEOS) with electrical status epilepticus during sleep (ESES) may be recurrent and intractable. The real-time transcranial Doppler ultrasound–sleep-deprived video electroencephalogram (TCD-SDvEEG) can be used to observe the relationships among hemodynamic, electrophysiological, and clinical factors in a patient during therapy. This study reported the case of a healthy 5-year-old boy with AEOS.

Case presentation

The patient had initial seizures during sleep at the age of 1 year, with the left mouth pouting, left eye blinking and drooling for several seconds, and, sometimes, the left upper-limb flexion and head version to the left, lasting for 1–2 min. The combined antiepileptic drug regimens, including valproate, lamotrigine, and clonazepam, failed in the present case. Therefore, the add-on high-dose methylprednisolone therapy was provided. Also, the serial TCD-SDvEEG was used to monitor the dynamic changes before and after add-on steroid treatment. The results showed less than 15% variation in the range of blood flow fluctuation with spikes during non-rapid eye movement sleep after treatment. This was similar to the outcomes in healthy children and also accorded with the clinical improvements such as seizure control, drooling control, and language ability melioration. However, 95% of spike-wave index (SWI) was still maintained. The improvements in cerebral hemodynamics and clinical manifestations were faster and earlier than the SWI progression.

Conclusions

The real-time TCD-SDvEEG was highly sensitive in detecting therapeutic changes. The findings might facilitate the understanding of the mechanisms underlying neurovascular coupling in patients with AEOS accompanied by ESES.

Influence of sleep on developing brain functions and structures in children and adolescents: A systematic review

This systematic review examined the associations between sleep and brain functions and structures in children and adolescents aged 1-17 ys. Included studies (n = 24) were peer-reviewed and met the a priori determined population (apparently healthy children and adolescents aged 1 y to 17 ys), intervention/exposure/comparator (various sleep characteristics including duration, architecture, quality, timing), and outcome criteria (brain functions and/or brain structures, excluding cognitive function outcomes). Collectively, the reviewed studies report some relationships between inadequate sleep and resultant differences in brain functions or structures. Although the research presented supports and offers more insight into the importance of sleep for the developing brain of children and adolescents, no firm conclusions that apply broadly may be drawn from these results, particularly because of the diversity of the sleep variables and outcomes. However, it is clear that sleeping habits in the pediatric population should be prioritized. Health care providers should continue to recommend healthy sleep practices and adequate time for sleep, as they are essential for overall health, including brain health.

Measurement of neurovascular coupling in human motor cortex using simultaneous transcranial Doppler and electroencephalography

OBJECTIVE

Event-related desynchronization (ERD) is a relative power decrease of electroencephalogram (EEG) signals in a specific frequency band during physical motor execution, while transcranial Doppler (TCD) measures cerebral blood flow velocity. The objective of this study was to investigate the neurovascular coupling in the motor cortex by using an integrated EEG and TCD system, and to find any difference in hemodynamic responses in healthy young male and female adults.

APPROACH

Thirty healthy volunteers, aged 20-30 years, were recruited for this study. The subjects were asked to perform a motor task for the duration of a provided visual cue. Simultaneous EEG and TCD recording was carried out using a new integrated system to detect the ERD arising from the EEG signals, and to measure the mean blood flow velocity of the left and right middle cerebral arteries from bilateral TCD signals.

MAIN RESULTS

The results showed a significant decrease in EEG power in the mu band (7.5-12.5 Hz) during the motor task compared to the resting phase. It showed significant increase in desynchronization on the contralateral side of the motor task compared to the ipsilateral side. Mean blood flow velocity during the task phase was significantly higher in comparison with the resting phase at the contralateral side. The results also showed a significantly higher increase in the percentage of mean blood flow velocity in the contralateral side of motor task compared to the ipsilateral side. However, no significant difference in desynchronization or change of mean blood flow velocity was found between males and females.

SIGNIFICANCE

A combined TCD-EEG system successfully detects ERD and blood flow velocity in cerebral arteries, and can be used as a useful tool to study neurovascular coupling in the brain. There is no significant difference in the hemodynamic responses in healthy young males and females.