Alireza Kamali Asl

Assistant Professor, Nuclear Engineering Dept., Shahid Beheshti University, Tehran, Iran

[ 1 ] - Sensitivity Optimization for a New Radio-Chromic Dosimeter (PRESAGE)

Introduction: Different dosimetric modalities (e.g., ionization chambers, semiconductors, TLDs, radiographic films) often have some problems determining isodose curves and percentage depth doses in high dose gradient regions. Research has been ongoing to develop portable high resolution dosimetry devices with accurate absolute dosimetry capabilities and easy data analysis. The ‘PRESAGE’ dosimet...

[ 2 ] - Gamma Knife Simulation Using the MCNP4C Code and the Zubal Phantom and Comparison with Experimental Data

Introduction: Gamma Knife is an instrument specially designed for treating brain disorders. In Gamma Knife, there are 201 narrow beams of cobalt-60 sources that intersect at an isocenter point to treat brain tumors. The tumor is placed at the isocenter and is treated by the emitted gamma rays. Therefore, there is a high dose at this point and a low dose is delivered to the normal tissue surroun...

[ 3 ] - Collimator-detector response compensation in molecular SPECT reconstruction using STIR framework

Introduction:It is well-recognized that collimator-detector response (CDR) is the main image blurring factor in SPECT.  In this research, we compensated the images for CDR in molecular SPECT by using STIR reconstruction framework. Methods: To assess resolution recovery capability of the STIR, a phantom containing five point sources along with a micro Derenzo p...

[ 4 ] - ارزیابی کمی اثرات ناشی از پراکندگی تابش بر کیفیت تصاویر SPECT حاصل از موازی ساز فن بیم با استفاده از شبیه سازی مونت کارلو

  مقدمه: در این کار با استفاده از شبیه سازی مونت کارلو به ارزیابی کمی اثرات ناشی از پراکندگی تابش بر کیفیت تصاویر SPECT حاصل از موازی ساز فن بیم پرداخته شده است.   مواد و روش­ ها: برای مدل سازی سیستم تصویربرداری از کد مونت کارلو MCNP4C استفاده گردید. به منظور بررسی میزان تاثیر پراکندگی تابش بر کیفیت تصویر از یک فانتوم آب استفاده شد و تابع خط گستر( LSF ) و تابع تغییر انتقال( MTF ) در حضور و عدم ...

[ 5 ] - Ultra-Fast Image Reconstruction of Tomosynthesis Mammography Using GPU

Digital Breast Tomosynthesis (DBT) is a technology that creates three dimensional (3D) images of breast tissue. Tomosynthesis mammography detects lesions that are not detectable with other imaging systems. If image reconstruction time is in the order of seconds, we can use Tomosynthesis systems to perform Tomosynthesis-guided Interventional procedures. This research has been designed to study u...