The Effect of Resection Extent Upon Postoperative Outcome of Seizures and Memory in Anterior Temporal Lobectomy with Amygdalohippocampectomy / 대한간질학회지

PURPOSE: To investigate the relationship of the resection extent of hippocampus and temporal neocortex with the postsurgical outcome in patients with mesial temporal lobe epilepsy (TLE). METHODS: Sixty-eight patients with TLE underwent brain MRI pre- and post-operatively. They were divided into two groups by seizure outcomes:seizure free group (SF, N=54) and non-seizure free group (NSF, N=14). Patients were classified further according to the post-surgical memory changes:MD group (with postsurgical memory decline, N=15) and NMD group (without postsurgical memory decline, N=16). The hippocampal resection was estimated by subtracting the length of post-surgical hippocampus from the pre-surgical length. The resection of temporal neocortex was measured by comparing the resection lengths on superior, middle, inferior and basal temporal gyri shown on three dimensional brain MRI. RESULTS: The mean extent of hippocampal resection was significantly larger in SF than in NSF (33.2+/-7.5 mm vs. 24.8+/-7.4 mm p=0.001) while that between MD and NMD was not significantly different. The resection extent of temporal neocortex was not significantly different between SF and NSF as well as between MD and NMD, but the resection extent of basal temporal gyrus of left TLE was significantly larger in MD than in NMD. CONCLUSIONS: The hippocampal resection was significantly greater in SF. The overall resection extent of the temporal neocortex did not correlate to the surgical outcomes of seizures or memory although that of the basal temporal gyrus of the left TLE was larger in MD.

Regional Cerebral Blood Flow Patterns in Unilateral Mesial Temporal Lobe Epilepsy: Statistical Parametric Mapping of Ictal and Interictal SPECT / 대한간질학회지

PURPOSE: To investigate the regional cerebral blood flow of patients with mesial temporal lobe epilepsy (mTLE), we performed the statistical parametric mapping (SPM) analysis in patients with mTLE. METHODS: Nineteen normal subjects and 38 with mTLE (22 left, 16 right) underwent brain SPECT. For SPM analysis, all SPECT images were spatially normalized and then smoothed. The left and right mTLE groups were statistically compared with normal subjects, and the paired t-test was performed between ictal and interictal SPECTs. The positive and negative contrasts displayed the regions of hypo- or hyper-perfusion, respectively. The significance level was set to false discovery rate corrected p<0.05. RESULTS: In the interictal state, the ipsilateral hippocampus, both thalami, pericentral gyri, left insula, and both medial frontal lobes showed hypoperfusion, whereas both posterior lateral temporal areas showed hyperperfusion. In the ictal state, the rCBF of ipsilateral temporal lobe to the epileptic focus and both prefrontal white matters increased, while both medial frontal lobes showed hypoperfusion. In the right mTLE, the left hippocampus and insula showed hypoperfusion during the interictal state. In the paired t-test, ipsilateral temporal lobe, hippocampus, thalamus, putamen, insula, and both precentral gyri showed hyperperfusion. CONCLUSIONS: Surprisingly, the hypoperfusion and hyperperfusion patterns of patients with mTLE were similar both in the interictal and ictal states. These findings indicate that the occurrence and propagation of epileptic discharges happen not only in the ictal state but also during the interictal period. The hypoperfusion patterns suggest that the cortico-thalamo-hippocampal-insula circuit was impaired during the interictal state while temporal and prefrontal regions showed hypofunction during the ictal period.

Rasmussen's Encephalitis

We herein report a case of intractable epilepsy that occurred in a 7-year-old girl, which is consistent with radiological and clinicopathological hallmarks of Rasmussen's encephalitis. The patient showed characteristic primary unilateral involvement with secondary bilateral propagation. Microscopically, the cortical atrophy due to neuronal loss, intense GFAP-immunoreactive astrogliosis, neuronophagia, perivascular lymphocytic infiltration and microglial nodules was seen throughout the cortex and white matter. No viral inclusions were noted; no cytomegalovirus, herpes simplex virus or Epstein-Barr virus was found by in situ hybridization. Granular immunofluorescence for C4, C1q and IgG within the blood vessel walls was noted, and ultrastructurally, only nonspecific vascular injury was found. Rasmussen's encephalitis is a diagnosis of exclusion; it can be diagnosed by the combination of clinical manifestation, neuroimaging and characteristic pathologic features.

Measurement of Corpus Callosal Area in Juvenile Myoclonic Epilepsy Using High Resolution Magnetic Resonance Imaging / 대한간질학회지

BACKGROUND: To investigate the change of corpus callosal area in juvenile myoclonic epilepsy (JME), the mid-sagittal areas of corpus callosum and its seven sub-regions were measured in JME patients and normal subjects. METHODS: Nineteen JME patients (22.6+/-5.0 year-old, 6 males, 13 females) and 19 normal controls (22.9+/-7.3 year-old, 6 males, 13 females) underwent 1.6 mm thickness whole brain SPGR MRI. Exact mid-sagittal image was obtained with image reconstruction and geometric correction. According to Witelson's work, the area of corpus callosum was divided into 7 sub-regions (a1 to a7 from anterior to posterior) with a semi-automated method. In each sub-region, the pixel number was counted according to ROI definition. The whole cerebral volume was measured. The mid-sagittal cerebral area was measured by tracing inner surface of skull and basal cortical surface of the cerebrum except for corpus callosum and cerebellum. The difference of corpus callosum areas between JME patients and normal controls were tested by t-test and ANCOVA. RESULTS: There was no difference in sex [chi-square(1)=1.00, chi square] and age (p=0.941, Mann-Whitney U test). The areas of rostrum (p0.25, t-test). CONCLUSION: Rostrum and rostral body are significantly smaller in JME patients, which suggests frontal lobe abnormality in JME. This finding is consistent with previous studies reported structural and functional abnormalities of frontal lobe in JME.

Surgical Treatment of Seizures in Malformations of Cortical Development (MCD) / 대한간질학회지

OBJECT: Surgical treatment of cortical dysplasias (CDs) presenting with intractable seizures is challenging, because isualization/localization of the lesion is difficult, correlation with seizure foci needs comprehensive investigations, and the reported surgical results are not satisfactory. We report our result of surgical treatment of CD classified from the surgical point of view. METHODS: Definition of CD was a visible dysplastic lesion on MRI or MRI-negative (normal MRI) case with pathological diagnosis of moderate to severe dysplasia. During the last 4.5 years, we had operated on 36 cases of intractable epilepsy with CDs. We divided the 36 cases into 4 groups ; Group A : diffuse bilateral hemispheric dysplasia, Group B : diffuse lobar dysplasia, Group C : focal dysplasia, and Group D : moderate to severe degree of cortical dysplasia with normal MRI. All but one patient in Group C were monitored at EMU using subdural electrodes for seizure localization and functional mapping. RESULTS: The incidence of CD in the whole epilepsy surgery cases was 12.4%. Mean age was 21.3 years. Mean age at seizure onset was 8.5 years. Mean follow up period was 26.0 months. Twenty-six (72.2%) patients (20 and 6, respectively) belong to Engel Class I and II. There were 5, 9, 9, and 13 cases in Groups A, B, C, and D, respectively. Groups A and B had significantly lower age at seizure onset and significantly poorer surgical outcome compared to Groups C and D (p<0.05). If the outcome was compared on the extent of removal of CD, patients with completely removed CD had very significantly better outcome than those with partial removal (p<0.001). CONCLUSIONS: We conclude that intractable epilepsy with CD can be treated surgically with comprehensive preoperative approaches. Deliberate resective procedures aiming at complete removal of dysplastic tissue ensure excellent seizure control without permanent neurological deficit.