Utility of electroencephalography in the evaluation of common neurologic conditions in children

Validation of a smartphone-based EEG among people with epilepsy: A prospective study

Our objective was to assess the ability of a smartphone-based electroencephalography (EEG) application, the Smartphone Brain Scanner-2 (SBS2), to detect epileptiform abnormalities compared to standard clinical EEG. The SBS2 system consists of an Android tablet wirelessly connected to a 14-electrode EasyCap headset (cost ~ 300 USD). SBS2 and standard EEG were performed in people with suspected epilepsy in Bhutan (2014-2015), and recordings were interpreted by neurologists. Among 205 participants (54% female, median age 24 years), epileptiform discharges were detected on 14% of SBS2 and 25% of standard EEGs. The SBS2 had 39.2% sensitivity (95% confidence interval (CI) 25.8%, 53.9%) and 94.8% specificity (95% CI 90.0%, 97.7%) for epileptiform discharges with positive and negative predictive values of 0.71 (95% CI 0.51, 0.87) and 0.82 (95% CI 0.76, 0.89) respectively. 31% of focal and 82% of generalized abnormalities were identified on SBS2 recordings. Cohen's kappa (κ) for the SBS2 EEG and standard EEG for the epileptiform versus non-epileptiform outcome was κ = 0.40 (95% CI 0.25, 0.55). No safety or tolerability concerns were reported. Despite limitations in sensitivity, the SBS2 may become a viable supportive test for the capture of epileptiform abnormalities, and extend EEG access to new, especially resource-limited, populations at a reduced cost.

Primary sleep disorders in people with epilepsy: clinical questions and answers

The questions facing clinicians with patients with sleep disorder and epilepsy are addressed in this article. Both adult and child epilepsy are discussed in the context of the most typical questions a clinician would have, such as "Are parasomnias more common in people with epilepsy?", "Is sleep architecture abnormal in children with epilepsy", along with outcomes of numerous questionnaire-based, case-based, and double-blind placebo studies on such aspects as sleep duration, daytime sleepiness, anxiety and fears, limb movement, nocturnal seizures, agitation, behavioral disorders, and learning disorders.

High-Frequency Oscillations Recorded on the Scalp of Patients With Epilepsy Using Tripolar Concentric Ring Electrodes

Epilepsy is the second most prevalent neurological disorder ([Formula: see text]% prevalence) affecting [Formula: see text] million people worldwide with up to 75% from developing countries. The conventional electroencephalogram is plagued with artifacts from movements, muscles, and other sources. Tripolar concentric ring electrodes automatically attenuate muscle artifacts and provide improved signal quality. We performed basic experiments in healthy humans to show that tripolar concentric ring electrodes can indeed record the physiological alpha waves while eyes are closed. We then conducted concurrent recordings with conventional disc electrodes and tripolar concentric ring electrodes from patients with epilepsy. We found that we could detect high frequency oscillations, a marker for early seizure development and epileptogenic zone, on the scalp surface that appeared to become more narrow-band just prior to seizures. High frequency oscillations preceding seizures were present in an average of 35.5% of tripolar concentric ring electrode data channels for all the patients with epilepsy whose seizures were recorded and absent in the corresponding conventional disc electrode data. An average of 78.2% of channels that contained high frequency oscillations were within the seizure onset or irritative zones determined independently by three epileptologists based on conventional disc electrode data and videos.

Diagnostic yield of electroencephalograms in infants and young children with frequent paroxysmal eye movements

Paroxysmal eye movement events are common in children. Many infants and young children are referred for a routine or a video-electroencephalography study. When epileptic, these events form part of a seizure and rarely occur as an isolated ictal event. The yield of the electroencephalogram in determining the nature of isolated paroxysmal eye movement episodes has not been reported. We reviewed our experience with video-electroencephalography studies in patients referred for paroxysmal eye movements. Twenty-one cases were analyzed, of which almost half were cognitively normal. All video-electroencephalography studies captured events that were found to be nonepileptic, including 6 records with interictal epileptiform activity. The semiology of the events differed between cognitively impaired individuals, who had more lateral eye deviation episodes, and normal patients, who showed blinking as a major manifestation. In conclusion, video-electroencephalography studies are probably not indicated in infants and young children with paroxysmal eye movements as their sole complaint.

Childhood epilepsy, attention problems, and ADHD: review and practical considerations

Children with epilepsy have a significant risk for problems with attention and/or attention deficit hyperactivity disorder. Clinical studies suggest a prevalence of 30% to 40%. Inattention is more common than hyperactivity and impulsivity. Additional central nervous system dysfunction and intractable seizures are major risk factors. Treatment should include psychoeducational interventions and medication. Stimulant drugs are safe and effective in children with epilepsy and currently are first-line agents for treatment of attention problems in this population.

Does sleep or sleep deprivation increase epileptiform discharges in pediatric electroencephalograms?

OBJECTIVE

Sleep deprivation before obtaining an electroencephalogram (EEG) is believed both to increase the likelihood of sleep during an EEG and to increase the detection of interictal epileptiform discharges. However, depriving a child of sleep poses a burden on both the parent and the child. The objective of this study was to compare the effects of sleep, standard sleep deprivation, partial sleep deprivation, and no sleep deprivation on the odds of an epileptiform abnormality in outpatient pediatric EEGs.

METHODS

Data were collected from all pediatric EEGs performed at a busy, university-based neurologic practice during two 2-month periods. During the first period, all EEGs were performed as ordered, either standard sleep-deprived (SSD) or non-sleep-deprived (NSD). During the second 2 months, SSD EEGs were performed per routine. However, non-SSD families were instructed to keep their children awake 2 hours later the night before the EEG. Those who complied were classified as partially sleep-deprived (PSD). Patient characteristics across protocols were compared with chi(2) and analysis of variance tests as appropriate. The odds of epileptiform and abnormal findings associated with sleep, NSD, PSD, and SSD EEGs were calculated using logistic regression.

RESULTS

Of 820 eligible EEGs, sleep occurred in 22% of NSD, 44% of PSD, and 57% of SSD EEGs. The sample size of this study allowed for an 85% power, with alpha of.05, to detect an absolute increased EEG yield of 10%. Neither the presence of sleep (odds ratio [OR]: 0.99; 95% confidence interval [CI]: 0.69-1.42) nor the use of PSD (OR: 0.90; 95% CI: 0.50-1.62) or SSD (OR: 0.96; 95% CI: 0.63-1.47) protocols increased the odds of epileptiform EEGs.

CONCLUSIONS

Sleep deprivation should not be used routinely to increase the yield of pediatric EEGs.

Study of attentional processes in children with idiopathic epilepsy by Conners' Continuous Performance Test

Before starting antiepilepsy therapy (T1) and after 1 year (T2), 19 children (7 female) affected by focal or generalized idiopathic epilepsy were considered with the aim of studying attention performance. All of the children received a neurological examination and clinical interview, electroencephalography (EEG) in wakefulness or sleep, and a standardized computerized measure of attention (Conners' Continuous Performance Test). At T1, 21% of the patients showed a specific attention disorder, and their percentage rose to 42% after 1 year, despite complete control of seizures. The prognosis was strongly correlated with (1) the presence of active seizures for a period of over 6 months, (2) the persistence of specific interictal abnormalities on an electroencephalogram at T2, and (3) the presence of emotional and behavioral disorders at the diagnosis of epilepsy. Our results confirm that attention disorders are frequent in children with idiopathic epilepsy. The Conners' Continuous Performance Test has proven useful both for diagnosis and follow-up over time.