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Objective Magnetic resonance (MR)-guided stereotactic laser amygdalohippocampectomy is a minimally invasive procedure for the treatment of refractory epilepsy in patients with mesial temporal sclerosis. Limited data exist on post-ablation volumetric trends associated with the procedure. Methods 10 patients with mesial temporal sclerosis underwent MR-guided stereotactic laser amygdalohippocampectomy. Three independent raters computed ablation volumes at the following time points: pre-ablation (PreA), immediate post-ablation (IPA), 24 hours post-ablation (24PA), first follow-up post-ablation (FPA), and greater than three months follow-up post-ablation (>3MPA), using OsiriX DICOM Viewer (Pixmeo, Bernex, Switzerland). Statistical trends in post-ablation volumes were determined for the time points. Results MR-guided stereotactic laser amygdalohippocampectomy produces a rapid rise and distinct peak in post-ablation volume immediately following the procedure. IPA volumes are significantly higher than all other time points. Comparing individual time points within each raters dataset (intra-rater), a significant difference was seen between the IPA time point and all others. There was no statistical difference between the 24PA, FPA, and >3MPA time points. A correlation analysis demonstrated the strongest correlations at the 24PA (r=0.97), FPA (r=0.95), and 3MPA time points (r=0.99), with a weaker correlation at IPA (r=0.92). Conclusion MR-guided stereotactic laser amygdalohippocampectomy produces a maximal increase in post-ablation volume immediately following the procedure, which decreases and stabilizes at 24 hours post-procedure and beyond three months follow-up. Based on the correlation analysis, the lower inter-rater reliability at the IPA time point suggests it may be less accurate to assess volume at this time point. We recommend post-ablation volume assessments be made at least 24 hours post-selective ablation of the amygdalohippocampal complex (SLAH).

ÖZETELEKTROMANYETİK SİLAH SİSTEMLERİNİN İNCELENMESİ ve BİR UYGULAMA ÖRNEĞİBu tez, yeni teknolojiden yararlanarak tasarlanan, günümüz silah sistemlerine alternatif olarak geliştirilmeye çalışılan “Elektromanyetik Silah” sistemleri üzerine hazırlanmıştır. Tez içeriğinde elektromanyetik silahlarla normal silahların kıyaslanması yapılmış, var olan elektromanyetik silah modellerinden bahsedilmiştir. Çalışmada farklı elektromanyetik silahlardan bahsedilmiştir ancak özellikle raylı tip olarak isimlendirilen elektromanyetik silahların incelemesi ve analizi uygulamalı olarak araştırılmıştır.Giriş kısmında manyetik ve elektromanyetik alan bilgilerinden bahsedilmiştir. Konu ile alakalı detay ve hesaplamalar üzerinde durulmuştur. Sistemin çalışma prensibine, sağ el ve sol el kurallarına değinilmiştir. Çalışmanın uygulama aşamasında ateşleme kaynağı olarak 8 adet kondansatör kullanılmış ve sistemden 2613.9 Joule enerji elde edilmiştir. Gerekli şarj devresi ve havalı mermi itici sistemi hazırlanmıştır. Ateşlemenin iptal edilebilmesi için deşarj devresi tasarlanmıştır. Kondansatör grubunda bulunan gerilim ve mermi itici hava ölçümleri için gerekli ölçü düzenekleri hazırlanmıştır. Namlu ve mermi % 2’lik toleranslı olarak imal edilmiş ve sisteme monte edilmiştir. Namlu hariç bütün sistem şeffaf pleksiglas malzeme ile yapılan kutu içerisine yerleştirilmiştir. İmalatın her aşaması detaylı olarak verilmiştir.Atış denemeleri yapılarak çeşitli ölçümler elde edilmiştir. Teorik hesaplamalar ile uygulama sonuçları karşılaştırılmış ve grafiklerle gösterilmiştir.Anahtar Kelimeler:Elektromanyetik Silah, Elektromanyetik Fırlatıcı, Raylı Fırlatıcı, Elektromanyetik Alan, Raylı Silah.Ağustos, 2013 İsmail YILDIZABSTRACTAN INVESTIGATION ON ELECTROMAGNETIC WEAPON SYSTEMS AND A CASE STUDYThe thesis is prepared on the “Electromagnetic Weapons” that are designed through state-of-the-art technology and developed as an alternative to existing weapon systems. Throughout the study a comparison of electromagnetic and normal weapons is made and then information about existing electromagnetic weapons is given.Various electromagnetic weapons are referred in the study but the inspection and the analysis of electromagnetic weapons particularly named as rail type are made practically.In the introduction part, information on magnetic and electromagnetic fields is given. Some details and calculations on the topic are also given. The working principle of the system, right-hand and left-hand rules mentioned.In the application part of the study, 8 condensers are used as the source of ignition and 2613.9 Joules of energy is attained. The necessary charging circuit and airy bullet impeller are prepared. For the cancellation of the ignition a discharging circuit is designed. Necessary measuring assembly is constructed for the measurement of the voltage at the condenser group and for the air measurements of bullet impeller. The barrel and the bullet are produced and mounted to the system with 2% tolerance. All the system, excluding the barrel, are put the box made of transparent plexiglass material. The manufacturing processes are presented in detail.Some measurements are performed by making some firing tests. The theoretical calculations and application results are compared and presented with graphs.Key Words:Electromagnetic Weapons, Electromagnetic Launcher, Rail Launcher, Electromagnetic Field, Rail gun.August, 2013 İsmail YILDIZ