• 대한핵의학회:학술대회논문집
• /
• 1991.05a
• /
• pp.141.2-142
• /
• 1991

• Annals of Clinical Neurophysiology
• /
• v.11 no.1
• /
• pp.16-23
• /
• 2009

Background: The intermittent delta activity in electroencephalographies (EEGs) of patients with focal brain lesions has been reported to be a marker of an epileptogenic focus. This study investigated the concordance between the current source distribution (CSD) of the interictal epileptiform discharges (IEDs) and that of the background delta frequency bands (DFBs) of the scalp EEG. Methods: We collected scalp EEGs of 13 patients with focal epilepsy that contained uniregional IEDs and unilateral delta to theta slow waves. We applied a distributed source model using LORETA$^{(R)}$ to determine the CSD of the peak points of the IEDs and the DFBs of the background activity. Results: The CSDs of the DFBs were ipsilateral to the CSDs of the peak point of the averaged IEDs in ten patients, and bilateral with ipsilateral predominance in three patients. In the cases with an ipsilateral CSD of the DFB, 8 of 10 patients had concordance of the CSD localization between the averaged IED and the DFB. In the cases with bilateral CSD of the DFB, 2 of 3 patients had concordance of the CSD localization between the averaged IED and the DFB. Conclusions: The CSD localization and lateralization appear to be concordant between the IEDs and the DFB of background activity in epileptic patients. Therefore, the CSD of the DFB in EEGs with visually observable slow activities may predict those of IEDs.

• Journal of Korean Neurosurgical Society
• /
• v.47 no.1
• /
• pp.17-25
• /
• 2010

Objective: The focus of this study is brain plasticity associated with semantic aspects of language function in patients with medial temporal lobe epilepsy (mTLE) Methods: Using longitudinal functional magnetic resonance imaging (fMRI), patterns of brain activation were observed in twelve left and seven right unilateral mTLE patients during a word-generation task relative to a pseudo-word reading task before and after anterior temporal section surgery. Results: No differences were observed in precentral activations in patients relative to normal controls (n = 12), and surgery did not alter the phonological-associated activations. The two mTLE patient groups showed left inferior prefrontal activations associated with semantic processing (word-generation>pseudo-word reading), as did control subjects. The amount of semantic-associated activation in the left inferior prefrontal region was negatively correlated with epilepsy duration in both patient groups. Following temporal resection, semantic-specific activations in inferior prefrontal region became more bilateral in left mTLE patients, but more left-lateralized in right mTLE patients. The longer the duration of epilepsy in the patients, the larger the increase in the left inferior prefrontal semantic-associated activation after surgery in both patient groups. Semantic activation of the intact hippocampus, which had been negatively correlated with seizure frequency, normalized after the epileptic side was removed. Conclusion: These results indicate alternation of semantic language network related to recruitment of left inferior prefrontal cortex and functional recovery of the hippocampus contralateral to the epileptogenic side, suggesting an intra- and inter-hemispheric reorganization following surgery.

• Nuclear Medicine and Molecular Imaging
• /
• v.41 no.2
• /
• pp.166-171
• /
• 2007

GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, $GABA_{A}-receptor$ that allows chloride to pass through a ligand gated ion channel and $GABA_{B}-receptor$ that uses G-proteins for signaling. The $GABA_{A}$-receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate $GABA_{A}$-receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with $^{11}C-FMZ$, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, $^{18}F-fluoroflumazenil$ (FFMZ) has been developed to overcome $^{11}C's$ short half-life. $^{18}F-FFMZ$ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using $^{11}C-FMZ$ PET instead of $^{18}F-FDG$ PET, restrict the foci better and may also help find lesions better than high resolution MR. $GABA_{A}$ receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, $GAB_{A}$ imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas.

• Korean Journal of Clinical Laboratory Science
• /
• v.38 no.2
• /
• pp.141-146
• /
• 2006

Vagal nerve stimulation (VNS) has been proposed as a possible way to improve the control of refractory epilepsy. We report the effects following VNS treatment in patients with refractory epilepsy. Seventeen patients with a mean age of 12.8 years, ranging from 5 to 29 years, underwent the implantation of vagal nerve stimulation (Cyberonics, Houston, TX). We reviewed the clinical findings before and after VNS in seizure frequency, number of antiepileptic drugs (AED), and quality of life (QOL). All of the patients had intractable seizures, eleven of the patients had additional medical complications, three had hippocampus atrophy, one had encephalomalacia, five had encephalitis, one had pachygyria, and one had schizencephaly. Thirteen patients had symptomatic partial epilepsies, three patients had Lennox-Gastaut syndrome and one had cryptogenic partial epilepsy. The mean follow up duration was 35 months. The mean reduction of seizure frequency compared with baseline before VNS was 26.1% after 3 months (p<0.005), 41.9% after 6 months (p<0.001), 46.9% after 1 year (p<0.001), and 53% at the latest follow-up (p<0.001). Twelve patients showed an improvement of QOL such as mood, language, alertness, expression, and motor function. The most common side effects were transient hoarseness or voice change or cough, which was detected in six patients (35%) and wound infection in one patient (5%). This study has shown a good anti-seizure effect of VNS, decrease in seizure frequency and improvements in QOL. We concluded that VNS is a beneficial therapy in refractory epilepsy with a non-resectable epileptic focus. Further studies should be focused on the prediction of unresponsiveness and the adjustment of VNS parameters for maximum efficacy in patients with various medical histories.

• Journal of Korean Neurosurgical Society
• /
• v.62 no.3
• /
• pp.353-360
• /
• 2019

Epilepsy surgery that eliminates the epileptogenic focus or disconnects the epileptic network has the potential to significantly improve seizure control in patients with medically intractable epilepsy. Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) has been an established option for epilepsy surgery since the US Food and Drug Administration cleared the use of MRgLITT in neurosurgery in 2007. MRgLITT is an ablative stereotactic procedure utilizing heat that is converted from laser energy, and the temperature of the tissue is monitored in real-time by MR thermography. Real-time quantitative thermal monitoring enables titration of laser energy for cellular injury, and it also estimates the extent of tissue damage. MRgLITT is applicable for lesion ablation in cases that the epileptogenic foci are localized and/or deep-seated such as in the mesial temporal lobe epilepsy and hypothalamic hamartoma. Seizure-free outcomes after MRgLITT are comparable to those of open surgery in well-selected patients such as those with mesial temporal sclerosis. Particularly in patients with hypothalamic hamartoma. In addition, MRgLITT can also be applied to ablate multiple discrete lesions of focal cortical dysplasia and tuberous sclerosis complex without the need for multiple craniotomies, as well as disconnection surgery such as corpus callosotomy. Careful planning of the target, the optimal trajectory of the laser probe, and the appropriate parameters for energy delivery are paramount to improve the seizure outcome and to reduce the complication caused by the thermal damage to the surrounding critical structures.

• Clinical and Experimental Pediatrics
• /
• v.50 no.9
• /
• pp.896-900
• /
• 2007

Purpose : The aim of this study was to investigate the speech problems in benign rolandic epilepsy (BRE) according to the seizure focus in EEG and semiology. Methods : Twenty three patients [right origin (13 patients) or left side (10 patients)] who met the BRE criteria by International League Against Epilepsy (ILAE) were prospectively enrolled. We excluded the patients who had abnormal MRI or showed both side spikes in EEG. Computerized Speech Lab was used to assess the speech characteristics of the patients. Results : The error pattern of laryngeal articulation in BRE was exclusively substitution of stop consonants, these errors showed more frequent in the left group (16.0% vs 25.5%). Voice onset time (VOT) of stop consonants and Total duration (TD) of word in both groups were prolonged than normal control group, especially in left group (P<0.05). The first formant of vowel /o/ and second formant of /e/ were significantly decreased in left group (P<0.05). The right group scored wider on pitch range ($192.9{\pm}54.0Hz$) and energy range in spontaneous speech ($14.2{\pm}6.4db$) than the left group ($233.3{\pm}12.5Hz$, $19.4{\pm}9.3db$, respectively, P>0.05). Duration of counting (5 to 9) in left group slower than right group ($8.6{\pm}1.7$ vs $7.9{\pm}1.8sec$). Conclusion : Our data suggested that interictal spikes and seizures in either centrotemporal sides, especially left side group, may induce speech problems. We recommend the logopedic and phoniatric evaluations of speech in BRE patients.

• The Korean Journal of Nuclear Medicine
• /
• v.25 no.1
• /
• pp.17-26
• /
• 1991

뇌 혈류의 기능적 영상화는 간질병소의 국소화에 이용되고 있으며 측두엽성간질의 편측화에 여러가지 진단 방법이 이용되고 있으나 만족할만한 결과를 보이지 못하고 있다. 최근 PET또는 SPECT를 이용하여 측두엽성간질에서 발작 간에 측두엽 병소의 대사율 및 혈류의 감소가 나타나며, 이러한 소견은 발작 유발 병소의 편측화에 매우 유용할것이라는 보고들이 있다. 저자들은 측두엽성간질에서 간질 병소를 편측화 하는데에 $^{99m}Tc-HMPAO$ SPECT의 유용성을 평가 하고자 측두엽성간질 31예에서 발작 간의 $^{99m}Tc-HMPAO$ SPECT 소견, 뇌파, 자기 공명 영상 및 전산화 단층 소견을 비교하였다. SPECT 소견에 따른 나이, 병력 기간과 병발시 나이 등의 임상 지수 간에는 유의한 차이가 없었다. 31예의 환자중 23예에서(74.2%) 국소 뇌 혈류 감소를 보였으며 17예(54.8%)에서 측두엽에 관류 감소가 관찰 되었다. 비인두 뇌파 표준 뇌파는 24예(77.4%)에서 측두엽에 편측화를 보였으며 SPECT와 뇌파 양자가 모두 편측화된 경우 일치도는 8/12예 (66.7%) 였다. 16예에서 시행된 전산화 단층 영상은 모두 편측화를 보이지 못했으며 27예에서 시행된 자기 공명 영상에서는 단지 1예에서 편측화를 보였다. 이상의 결과로서 발작 간의 $^{99m}Tc-HMPAO$ SPECT는 측두엽성간질 병소의 편측화에 유용한 보조 검사로 생각된다.

• The Korean Journal of Nuclear Medicine
• /
• v.28 no.3
• /
• pp.307-312
• /
• 1994

Interictal single photon emission computed tomography of regional cerebral blood flow (rCBF SPECT) in 18 intractable temporal lobe epilepsy patients(8 male and 10 female patients: average 23.5 years old) were compared with 2.0 T magnetic resonance imaging (MRI). And surgical outcome was analysed with the findings, symptom duration and lateralization of temporal lobe. Preoperatively rCBF SPECT was done in all 18 patients with intravenous injection of 740 MBq 99mTc-HMPAO. MRI was also done preoperatively in 13 patients. Surgical outcome was classified by Engel's outcome classification(four-part classification recommended at the first Palm Desert conference). rCBF SPECT detected correctly lateralising abnormality of temporal lobe hypoperfusion in 13/18(72.2%), contralateral temporal lobe hypoperfusion in 2/18(11.1%) and showed no def-inite abnormality in 3/18(16.7%). The positive predictive value of unilateral temporal lobe hypoperfusion was 87%. MRI detected correct localising abnormality in 8/13(61.5%), such as hippocampal atrophy(7/13), asymmetric temporal horn(6/13), anterior temporal lobe atrophy(1/13), increased signal intensity from hippocampus(1/13) and calcific density(1/13), and no abnormal finding was noted in 5/13(38.5%). There was no false positive findings and the positive predictive value of MRI was 100%. Only 2 cases showed same lateralization findings in rCBF SPECT and MRI. There was no significant correlation between symptom duration and no abnormal findings on SPECT or MRI. Surgical outcome showed class I in 15/18(83.3%), and class II in 2/18(11.1%). One case of no abnormal finding in both SPECT and MRI showed class III surgical outcome. No class IV surgical outcome was noted. Surgical outcome, lateralization of epileptic focus in temporal lobe and abnormal findings in rCBR SPECT or MRI were not significantly correlated.