ارتقاي قدرت تفكيك زماني در يك سيستم‌ پرتونگاري مقطعي گسيل پوزيترون مغز مبتني بر زمان پرواز با استفاده از آرايه‌هاي سوسوزن - جبران‌ساز دولايه و شبيه‌سازي به روش مونت‌كارلو

Positron Emission Tomography (PET) imaging with Time-of-Flight (TOF) is one of the most advanced medical imaging techniques, widely used in brain disease diagnosis due to its high resolution an‎d improved signal-to-noise ratio. This study aimed to optimize the design of brain TOF-PET detectors through Monte Carlo simulations using GATE version 9.3. The investigated parameters included scintillator material (LSO an‎d LYSO), crystal length (3, 5, 10, an‎d 20 mm), reflector type (Teflon an‎d ESR), crystal surface (polished an‎d rough), an‎d dual-layer offset (DLO) configuration. Results showed that LYSO crystals with a 10 mm length, rough surface, an‎d ESR reflector achieved the best performance, with a coincidence time resolution (CTR) of 250 ps an‎d an energy resolution of 13.6%, demonstrating a significant improvement (17.4% in CTR an‎d 5.4% in energy resolution) compared to single-layer designs. This configuration, due to its balance between sensitivity an‎d temporal resolution, is ideal for brain PET applications. The DLO configuration further enhanced depth-of-interaction (DOI) localization, improving spatial accuracy an‎d image quality. These findings not only aid in detecting small brain lesions but also offer potential for reducing radiation dose an‎d scan time. However, challenges such as edge non-uniformities an‎d the need for precise calibration require further investigation. This research provides a foundation for advanced TOF-PET detector designs an‎d improved clinical imaging protocols.

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حسين عربي

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