• Annals of Clinical Neurophysiology
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• 제13권1호
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• pp.21-25
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• 2011

Periodic lateralized epileptiform discharges (PLEDs) had been debated whether it is ictal or non-ictal phenomenon. As most of PLEDs occur in patients with acute structural lesions, some epileptologists prefer PLEDS as a non-ictal phenomenon, rather an obscure epiphenomenon of etiological diseases. But, almost half of the patients with PLEDs do not have acute structural lesions in the brain and metabolic disorders or old CNS lesions may cause PLEDs and even more, no brain lesion was identified in some patients. There are many data supporting PLEDs as ictal phenomena. Occurrence of PLEDs usually accompanied by decreased mentality and is improved as PLEDs disappeared. Current SPECT study showed marked hyperperfusion in the lesion side of PLEDs, that is striking evidence of PLEDs as ictal phenomena. Also careful review of EEG with PLEDs revealed it is a dynamic process rather than a static state. Despite of these evidences, as PLEDs are an end-stage of animal status epilepticus models, it may be a transition of ictal to interictal state.

• 대한핵의학회지
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• 제34권3호
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• pp.169-182
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• 2000

목적: Ictal SPECT의 간질 병소를 찾는 민감도와 정확도는 각 연구마다 다르다. 발작 중에 발생할 수 있는 여러 가지 형태의 뇌혈류변화를 알아보고 이와 관련된 임상 요인들을 찾아보기 위하여 본 연구를 수행하였다. 대상 및 방법: 간질 수술을 받을 61명의 부분적 간질 환자들에서 interictal SPECT와 ictal SPECT를 시행한 후 두 영상을 차감하여 subtraction SPECT (sub-SPECT)영상을 구하였다. Sub-SPECT에서 보인 발작 중 뇌혈류변화의 형태는 1) 국소 뇌혈류증가(focal hyperperfusion), 2) 뇌혈류증가 플러스(hyperperfusion-plus), 3) 국소 뇌혈류감소(focal hypoperfusion), 그리고, 4) 혈류증가-감소 복합형(combined hyperperfusion-hypoperfusion)의 4가지로 나누었다. 각 형태 별로 간질초점 (epielptic focus)과의 일치율 (concordance rate)을 산출하였다. 결과: Conventional ictal SPECT 분석법의 간질촛점 진단율은 68.9%이었고, sub-SPECT의 진단율은 뇌혈류증가 만을 분석하였을때는 85.2%이었고, 뇌혈류 증가 및 감소를 모두 평가하였을 때는 91.3%이었다. 발작 중 국소 뇌혈류 감소는 측두엽외 간질에 비하여, 측두엽 간질에서 더 드물게 관찰되었다. 내측 측두엽에서만 발생한 뇌혈류증가는 내측 측두엽간질에서만 관찰되었고, 외측 측두엽에서만 발생한 뇌혈류증가는 신피질 측두엽간질에서만 관찰되었다. 해마 경화를 동반한 측두엽간질은 다른 병리소견에 비하여 발작 중 뇌혈류감소 현상을 매우 적게 보였다. 결론: Ictal SPECT를 분석할 때는 뇌혈류증가 뿐만 아니라 뇌혈류감소 현상도 유심히 보아야 하며, 발작 중 국소 뇌혈류감소의 기전으로 간질초점의 발작 중 초기 에너지고갈 (intra-ictal early exhaustion) 또는 간질초점 주변부로의 발작파 전파에 의한 steal 현상 등을 생각할 수 있지만 앞으로 규명하여야 할 과제이다.

• 대한핵의학회지
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• 제32권1호
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• pp.20-31
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• 1998

수술로서 간질 병소가 확인된 환자들을 대상으로 한 이 연구에서 발작기-발작간기 SPECT를 비교 판독하여 간질병소를 국소화한 것과 영상을 위치 이동하여 좌표를 일치시키고 정규화 하여 감산하여 얻은 감산 SPECT로 국소화한 것이 대등한 진단성능을 지니고 있으며 감산 SPECT로부터 MR이나 PET과 같은 수준의 정보를 얻을 수 있음을 확인하였다. 감산 SPECT에서 발작기 혈류 증가를 범위와 강도를 고려한 적절한 역치를 설정하여 발작기-발작간기 SPECT에 더하여 감산 SPECT가 얼마나 부가적 진단가치를 가지는지 확립하여야 한다고 생각하였다.

• 대한핵의학회지
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• 제37권1호
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• pp.24-33
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• 2003

Finding epileptogenic zone is the most important step for the successful epilepsy surgery. F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and single photon emission computed tomography (SPECT) can be used in the localization of epileptogenic foci. In medial temporal lobe epilepsy, the diagnostic sensitivity of FDG-PET and ictal SPECT is excellent. However, detection of hippocampal sclerosis by MRI is so certain that use of FDG-PET and ictal SPECT in medial temporal lobe epilepsy is limited for some occasions. In neocortical epilepsy, the sensitivities of FDG-PET or ictal SPECT are fair. However, FDG-PET and ictal SPECT can have a crucial role in the localization of epileptogenic foci for non-lesional neocortical epilepsy. Interpretation of FDG-PET has been recently advanced by voxel-based analysis and automatic volume of interest analysis based on a population template. Both analytical methods can aid the objective diagnosis of epileptogenic foci. Ictal SPECT was analyzed using subtraction methods and voxel-based analysis. Rapidity of injection of tracers, ictal EEG findings during injection of tracer, and repeated ictal SPECT were important technical issues of ictal SPECT. SPECT can also be used in the evaluation of validity of Wada test.

• 대한핵의학회지
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• 제29권4호
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• pp.445-450
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• 1995

신피질성 간질에서 발작기 뇌혈류 SPECT는 발작기 표면뇌파도를 기준으로 국소화했을때 67%의 국소화성능을 보였다. MR에 병변을 찾지 못한 57%(12예)에서도 혈류증가부위를 9예에서 찾을 수 있었다. 그리드삽입을 위한 수술부위 결정에 도움을 받은 경우가 MR에 나타난 병변유무와 상관없었다. 반면 MR에서는 43%에서 병변을 찾았다. 일부예에서 혈류증가부위의 확산을 관찰할 수 있었고 드물게 확산이 반대쪽 반구를 포함하는 경우가 있으나 대부분 국소화에 도움이 되는 자료로 사용할 수 있었다. 수술후 간질발작이 가라앉는 것을 확인한 결과를 준거로 성능비교 연구를 확장하여야 한다고 생각하였다.

• 대한핵의학회지
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• 제29권3호
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• pp.287-293
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• 1995

Anterior temporal lobectomy has become a widely used resective surgery in patients with medically intractable temporal lobe epilepsies. Prerequisites of this resection include the accurate localization of the epileptogenic focus and the determination that the proposed resection would not result in unacceptable postoperative memory or language deficits. The purpose of this study was to evaluate the performance of ictal SPECT compared to MRI findings for localization of epiletogenic foci in this group of patients. 11 patients who had been anterior temporal lobectomy were evaluated with ictal $^{99m}Tc$-HMPAO SPECT and MRI. MRI showed 8/11(73%) concordant lesion to the side of surgery and ictal SPECT also showed 8/11(73%) concordant hyperperfusion. In 3 cases with incorrect or nonlocalizing findings of MRI, ictal SPECT showed concordant hyperperfusion. In 2 cases confirmed by pre-resectional invasive EEG, MRI showed bilateral and contralateral lesion but ictal SPECT showed concordant hyperperfusion. 3 delayed injection of ictal SPECT showed discordant hyperperfusion. Thus, ictal SPECT was a useful method for localizing epileptogenic foci in temporal lobe epilepsis and appeared complementay to MRI.

• Annals of Clinical Neurophysiology
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• 제13권1호
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• pp.26-30
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• 2011

Although the pathophysiologic mechanism is unknown, there has been long-running debate on whether periodic discharges such as periodic lateralized epileptiform discharges (PLEDs) and generalized periodic epileptiform discharges are an ictal or interictal EEG pattern. The goal of this review is to give evidence that such periodic discharges on EEG are not ictal phenomenon and just represent underlying acute brain damage. This review includes coma with epileptiform EEG pattern and its prognostic and therapeutic implications. Based on previous reports, rather than taking the view PLEDs represent either an underlying ictal process or an electrographic correlate of neuronal injury, it would be more reasonable that PLEDs are considered as a dynamic pathophysiological state in which unstable neurobiological processes create an ictal-interictal continuum.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.335-337
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• 2002

The aim of this study was investigate the epileptogenic zone in temporal lobe epilepsy (TLE). We evaluated the subtraction image of interictal SPECT from ictal SPECT coregistered to 3-dimensional (3D) MRI, and compared with the normal healthy SPECT using a SPM99. Forty-nine patients with TLE (M:F=28:21, mean age: 33${\pm}$2.1 years) underwent a pairs of ictal and interictal SPECT. We performed subtraction interictal SPECT from ictal SPECT in TLE patients. In addition, using SPM methods and t-statistics, SPECT images of the TLE patients were compared with normal healthy SPECT on a voxel by voxel basis. The voxels with a p-value of less than 0.05, 0.005, 0.001 were considered to be significantly different. The subtraction results by ictal and interictal SPECT coincided with the significant rCBF changes when compare of the normal healthy SPECT using a SPM99. The results suggested that analysis of difference of the two methods using healthy normal SPECT with SPM99 is useful tool in evaluation of seizure focus in epilepsy.

• Clinical and Experimental Pediatrics
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• 제59권sup1호
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• pp.129-132
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• 2016

Ictal tachycardia and bradycardia are common arrhythmias; however, ictal sinus pause and asystole are rare. Ictal arrhythmia is mostly reported in adults with temporal lobe epilepsy. Recently, ictal arrhythmia was recognized as a major warning sign of sudden unexpected death in epilepsy. We present an interesting case of a child with ictal sinus pause and asystole. A 27-month-old girl was hospitalized due to 5 episodes of convulsions during the past 2 days. Results of routine electroencephalography (EEG) were normal, but she experienced brief generalized tonic seizure for 3 days. During video-monitored EEG and echocardiography (ECG), she showed multiple myoclonic seizures simultaneously or independently, as well as frequent sinus pauses. After treatment with valproic acid, myoclonus and generalized tonic seizures were well controlled and only 2 sinus pauses were seen on 24-hour Holter ECG monitoring. Sinus dysfunction should be recognized on EEG, and it can sometimes be treated successfully with only antiepileptic medication.

• 대한핵의학회지
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• 제26권2호
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• pp.244-250
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• 1992

Both interictal and ictal $^{99m}Tc-HMPAO$ brain SPECT were performed in 22 patients with medically intractable epilepsy. Localization of epileptic foci in our patients was made by combined results of EEG and other tests, including Wada test, magnetic resonance imaging, and neuropsychometric test. Among them, ictal $^{99m}Tc-HMPAO$ SPECT, localized epilptic foci in 20 of 22 patients and provided evidence of epileptic focus in 12 patients by demonstrating maximally increased regional cerebral perfusion (rCP) in epileptic foci during the ictal study with decreased rCP in interictal study. Ictal $^{99m}Tc-HMPAO$ SPECT was particularly useful for investigating epileptic foci, and when correlated with simultaneously recorded ictal EEG, provided further insight for localizing epileptic foci. Conclusively, $^{99m}Tc-HMPAO$ SPECT is. a useful, noninvasive method of localizing epileptic activity which may be particularly important for presurgical investigations, especially in those patients without large morphological lesions.