Faculty Bibliography

The interactions between sleep and epilepsy have been recognized for centuries. The electroencephalogram and more recently the polysomnogram have helped us understand these interactions. Certain epilepsy syndromes are more common during sleep, and frequently a sleep disorder is misdiagnosed as epilepsy. Management of epilepsy includes improvements in sleep quality and quantity, and aggressive treatment of epilepsy has a positive impact on sleep disorders

SUMMARY:: The EEG is helpful in the evaluation of patients with altered mental status and can provide clues for the underlying cause of certain entities. There are few descriptions of the EEG findings in patients with West Nile virus (WNV) infection. We describe the clinical presentation as well as the electroencephalographic findings in five patients with WNV encephalitis. Review of the records of all cases of WNV infection seen at the Mayo Clinic from 1999 to 2003, in which an EEG had been performed. Five patients with WNV encephalitis, in whom an EEG was performed, were found. All the patients had altered mental status and the EEG showed moderate to severe degrees of generalized slowing. Three of the patients had triphasic waves on the EEG. The patients did not have any metabolic disorder or electrolyte abnormalities that could account for these findings. EEG findings in WNV are consistent with an encephalopathic pattern and show varying degrees of generalized slow wave abnormalities and in some cases triphasic waves

Sleep disorders are common in childhood. The prevalence of childhood sleep disorders is higher in chronic neurologic disorders, specifically epilepsy. Sleep needs, requirements, and structure are different in children compared with adults. These variables are disrupted severely in patients with epilepsy. Electroencephalogram abnormalities, nocturnal seizures, and medications may contribute further to sleep problems and affect daytime functioning. These sleep disturbances may worsen seizure control and affect quality of life. This article offers an overview of the normal sleep patterns in children, describes the interaction of electroencephalogram, sleep, and commonly found sleep disorders, and reviews the current literature of the main sleep disturbances found in children with epilepsy.

We used regression analysis to compare the semiologic features of temporal lobe seizures that occur during sleep (TLS-S) and wake (TLS-W) in the same patient. Most semiologic features correctly lateralized seizure activity during either sleep or wake. No significant differences were found between TLS-S and TLS-W in the 18 semiologic features analyzed. The diagnostic value of TLS-S semiology is similar to that of TLS-W semiology

A 56-year-old woman presented with an acute confusional state and moderate global aphasia. Thyroperoxidase antibody level was elevated (3,890 IU/mL) and SREAT was diagnosed. MRI findings were normal. Cerebrospinal fluid examination revealed only a mildly increased protein. The initial electroencephalogram EEG showed slowing and markedly decreased amplitude over the left hemisphere and left temporal sharp waves. An EEG performed after treatment with intravenous steroids showed a significant improvement of the background slowing, which correlated with clinical improvement. One week later, the patient had an episode of forced head-turning and fencing posture to the right. The EEG shortly afterward showed slowing and a decreased amplitude over the right hemisphere. Continuous EEG monitoring was performed at the time of steroid treatment. Again, there was a significant improvement of the EEG after this treatment that correlated with the clinical condition. SREAT is characterized by fluctuations in mental status and variable EEG findings. These patients often show an excellent clinical improvement to immunosuppressive therapy, including corticosteroids. This case report documents the dramatic clinical and EEG improvement with steroid therapy