Surgical Treatment of Postencephalitic Epilepsy

Encephalitis is often followed by chronic intractable epilepsy. Many of these patients pose significant challenges to the localization of seizure generators and to the strateges for management of intractable epilepsy. The authors analysed 17 patients with postencephalitic epilepsy(PEE), who underwent resective surgeries. Most patients had been accompanied by coma, convulsive status epilepticus, and focal motor deficit at the time of encephalitis. MRI studies showed variable degree of brain damage: hippocampal sclerosis only(n=5), neocortical gliosis only(n=6), and both(n=5). Analysis of ictal semiology revealed a predominant temporo-limbic seizure pattern in 7, a variable extralimbic patterns in 6, and unclassified in 4 patients. Surgical resection includes temporal(n=11), frontal(n=3), centroparietal(n=1), multilobar(n=2), and callosotomy(n=2). Surgical outcome was graded as class 1(n=8), class 2(n=2), class 3(n=4), and class 4(n=3). It is concluded that surgical result was promising despite the traditional concerns about localizing problem in the setting of PEE. Surgical treatment should be, therefore, considered if localizing information is persistent. Intracranial EEG recording was very useful to delineate the area of seizure onset. MRI abnormalities were not always correlated with ictal onset zone in the patients with PEE.

Congenital bilateral perisylvian syndrome: analysis of the first four reported Korean patients

The advent of MRI technique has enabled the diagnosis of neuronal migration disorders(NMD) and made it possible to make "in vivo" diagnosis. Congenital bilateral perisylvian syndrome(CBPS) is a recently described disease identify characterized by pseudobulbar palsy, epilepsy, mental retardation, and migration disorders in the bilateral perisylvian area. We have identified four CBPS patients based on neuroimaging and dysarthria patterns among the candidates for epilepsy surgery. All the patients had orofacial diplegia and variable degrees of mental retardation. In the spectrographic analysis of dysarthria, the loss of specific characteristics of formants of vowels and increment of noise in the high frequency formants were observed. Epilepsy was present in all, but only one patient showed intractable seizure requiring surgical intervention. MRI was most helpful in identifying NMD and polymicrogyria in both centroparietal areas in this context. Great alertness is needed to identify this disorder to determine the etiology of epilepsy and dysarthria of uncertain origin.

Rolandic Cortical Dysplasia: Case Report

The advent of MRI enables us to make an in-vivo diagnosis of cortical dysplastic lesions which are highly epileptogenic and show the variety of seizure patterns. Authors report a case of rolandic cortical dysplasia who had highly intractable focal motor clonic seizures. Invasive recording with subdural grid was very helpful in delinating the epileptogenic area as well as in function mapping of eloquent areas. Total removal of dysplastic lesion could treat this highly intractable epilepsy succesfully.