Zemin aktivitesi değerlendirilmesinde kantitatif elektroensefalografi analiz yöntemi

Giriş: Elektroensefalografi (EEG), beynin oluşturduğu elektriksel sinyallerin kayıtlanmasını ve analizini içeren ve beynin anormal elektriksel aktivitesinin lokalizasyonu, şiddeti ve yayılımı hakkında bilgi veren bir tanı yöntemidir. EEG görsel olarak, değerlendiricinin tecrübesi ve bilgisi doğrultusunda subjektif yani kalitatif olarak değerlendirilebileceği gibi, bilgisayar yardımıyla, sayısal veriler üzerinden, objektif yani kantitatif olarak da değerlendirilebilir. Bu çalışmada, sayısal verilere dayanan, zemin aktivitesinin kantitatif bir analiz yöntemi olan, “Fast Fourier Transformation” (FFT) yönteminin işlevselliğinin araştırılması amaçlandı. Gereç ve Yöntem: Çalışmaya Ege Üniversitesi Tıp Fakültesi (EÜTF) Nöroloji kliniğine başvuran yapısal serebral lezyonu ve/veya epileptik nöbetleri olan 73 olgu alındı. Olgular klinik özellikleri ve radyolojik bulguları doğrultusunda gruplandırıldı. Her bir gruptaki olguların zemin aktiviteleri kantitatif ve kalitatif yöntemlerle değerlendirildi. Olguların kantitatif zemin aktivitesi analizlerinin radyolojik bulgularla uyumu değerlendirildi. Olguların analiz sonuçları kontrol grubuyla karşılaştırıldı. Bulgular: İskemik serebral lezyonu olan ve iskemik doğada olmayan kortikal yapısal lezyonu olan gruplarda kantitatif zemin aktivitesi analizinin radyolojik bulgularla uyumlu, anlamlı lokalize edici değer taşıdığı görüldü. Sonuç: Kantitatif zemin aktivitesi analizi yöntemi, kortikal yerleşimli fokal lezyonların lokalizasyonunda uygulaması kolay ve güvenilir bir yöntem olabilir.

Quantitative analysis method of electroencephalography for the evaluation of back ground activity

Introduction: Electroencephalography (EEG), is a diagnostic method, involving registration and analysis of electrical signals arisen from brain and gives information about abnormal electrical activities' localization, intensity and distribution. EEG may be evaluated as visual, and subjective in other words quantitative, due to individual's experience and knowledge, nevertheless, it may be evaluated by aid of computer, and numerical datas, as objective, namely qualitative. In this trial, researching the functionality of “Fast Fourier Transformation” method was aimed, which is an quantitative analysis method of bacground activity, based on numerical data. Material and Methods: Seventy three cases which applied to Ege University, Department of Neurology, because of structural lesions and/or seizures were admitted to trial. Cases were seperated into groups, corresponding to clinical and radiological findings. For each group, background activities of cases were evaluated by quantitative and qualitative methods. Analysis of cases background activities, adaptation by radiological findings were evaluated. Analysis results of cases were compared with control group. Results: Quantitative background activity analysises of ıschemic serebral and nonischemic cortical structural Lesion groups were harmonious with radiological findings, and have expressive localization value Conclusion: Analysis of background activity by quantitative methods, may be a simple, reliable method for localization of cortical, focal lesions.

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