14345

12970

كارشناسي ارشد

الكترونيك

اصفهان : دانشگاه صنعتي اصفهان

1397

چهارده، ۱۱۱ص.: مصور، جدول، نمودار

رسول اميرفتاحي، ابوالقاسم زيدآبادي‌نژاد

مسعود سيدي، فرزانه شايق

1397/11/28

كتابنامه

برق

مهندسي برق و كامپيوتر

1397/12/01

ID12970

Noninvasive Deep Brain Stimulation Tissue Modeling and Study of Interferential Electric Fields Fariba Karimi fariba karimi@ec iut ac ir January 19 2019 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Assoc Prof Rassoul Amirfattahi fattahi@cc iut ac ir Co Supervisor Assoc Prof Abolghasem Zeidaabadi Nezhad zeidabad@cc iut ac ir Abstract The human brain is the most complex structure in the universe and yet there are a lot of mysteries about it Thereare around one billion people worldwide who suffer from kinds of brain diseases due to any malfunction of brain activity Brain stimulations which are generally divided into invasive and noninvasive methods are important tools for understand ing the brain functions and treating its disorders Despite many applications in diagnosing and treating brain disordersand improving its functions conventional noninvasive methods cannot directly modulate deep brain structures Directstimulation of these structures requires invasive methods such as deep brain stimulation which was invented in the late1980s Although invasive methods have been very successful its applications are very limited due to its significant risks Noninvasive deep brain stimulation inspired by the interferential current therapy is a bridge between conventional nonin vasive methods and deep brain stimulation It is introduced in 2017 to directly stimulate deep brain structures through scalpelectrodes In this study the interferential electric fields in a homogeneous and inhomogeneous cylinder and sphere werecomputed both analytically and numerically In addition they were computed numerically in a precise anatomical humanhead model Threshold approach exploiting the maximum envelope modulation amplitude along any orientation has beenused for determining the volume of tissue activated Results show that it is possible to directly stimulate deep structures Also by extracting the relationship between activated area and stimulation parameters a method is developed to determinethe stimulation parameters in order to achieve the desired activated area inverse problem In addition the activated areais computed more accurately with the help of microscopic axon models The results can be used to prove this method fromthe computational point of view In the following after designing and implementing the interferential current stimulator the noninvasive deep brain stimulation method applied to the cylindrical phantom containing a fluid with constant electricalconductivity The comparison of the measured voltage inside the phantom with the theoretical values has shown the validityof the stated theory In according with the great application and importance of this method and its challenges more exactinvestigation and in vivo evaluation are proposed for future researches Key Words 1 Noninvasive Deep Brain Stimulation 2 Interfering Electric Fields 3 AnatomicalHuman Head Model 4 Axon Modeling 5 Interferential Current Stimulator

رسول اميرفتاحي، ابوالقاسم زيدآبادي‌نژاد

مسعود سيدي، فرزانه شايق