مجال التميز | تميز دراسي وبحثي |
البحوث المنشورة |
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البحث (1): | |
عنوان البحث: | Gamma-ray imaging performance of the GRI+ Compton camera |
رابط إلى البحث: | https://iopscience.iop.org/article/10.1088/1748-0221/16/09/P09015 |
تاريخ النشر: | 14/09/2021 |
موجز عن البحث: |
GRI+ (Gamma-Ray Imager) is a cart-based Compton camera developed at the University of Liverpool. The system comprises three electrically-cooled semiconductor detectors; two planar double-sided strip detectors (Si(Li) and HPGe) and an HPGe coaxial detector. The mobile cart houses the necessary components for data acquisition and analysis, providing complete functionality for imaging gamma-ray sources in an industrial setting. This paper reports on the operation of the system and the methods used to improve intrinsic system performance. The processing chain for extracting information pertaining to gamma-ray interactions has been developed and the imaging performance is characterised using an analytical reconstruction code. The obtainable Angular Resolution Measure (ARM) from a Cs-137 point source placed 10.5 cm from the front of the Si(Li) cryostat was determined to be 4.12◦ after the application of data processing techniques. The system energy resolution, which is key to isotope identification and image quality, was calculated to be less than 0.5% at 1332.5 keV. |
المؤتمرات العلمية |
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المؤتمر (1): | |
عنوان المؤتمر: | 58th Annual Conference of the Particle
Therapy Co-Operative Group |
تاريخ الإنعقاد: | 10/06/2019 |
مكان الإنعقاد: | Manchester, United Kingdom |
طبيعة المشاركة: | Poster |
عنوان المشاركة: | Detecting prompt gammas as a means of dosimetry and
range verification measurements for treatment validation of high-energy beams in PBT |
ملخص المشاركة: | Protons are used in radiation therapy of cancerous tissue as they have the potential benefit of sparing dose to healthy tissue, due to manipulation of the positioning of the Bragg Peak as a function of depth in the body[1]. However, there is a need for a more precise method for range verification and the monitoring of dose delivery in real-time[2]. The University of Liverpool have developed the prompt-gamma imaging (GRI+) system, to measure the prompt gamma rays emitted and therefore the dose distribution of the proton beam during proton therapy. The system’s performance has so far been investigated using the simplest event sequence, which is a single interaction event in each detector. In this case, a spatial image resolution of around 5 mm was determined. However, for high photon energies, such as those observed in proton therapy, multiple interaction events are probable. In this study, the effective use of multiple interaction events will be discussed. The poster will also outline plans for an experiment to be conducted at the Clatterbridge Cancer Centre, UK, as part of the next phase of the project. |
المؤتمر (2): | |
عنوان المؤتمر: | The annual meeting of the IOP Astroparticle Physics Group, the High Energy Particle Physics Group, the Nuclear Physics Group |
تاريخ الإنعقاد: | 12/04/2021 |
مكان الإنعقاد: | Edinburgh, UK |
طبيعة المشاركة: | Poster |
عنوان المشاركة: | Imaging ability of the Compton camera imaging system
(GRI+) for thyroid phantom filled with 99mTc |
ملخص المشاركة: | Nuclear medicine imaging utilises the gamma-ray emitted from radiotracers to investigate physiological bodily functions. The distribution of radiotracer material in the body is commonly imaged using a single-photon emission computed tomography (SPECT) system [1]. However, SPECT systems display inherent limitations with respect to image spatial resolution and sensitivity because a SPECT system consists of a scintillation detection system equipped with a mechanical collimator. The University of Liverpool has developed a Compton camera imaging system (GRI+) consisting of two position-sensitive semiconductor detectors and one coaxial detector, and this imaging system is electronically collimated. The GRI+ system achieved an angular resolution of 8.5° for a point-like 137Cs source (662 keV) [2]. The current study investigated the imaging ability of the GRI+ system in medical applications by imaging a thyroid phantom, which was designed to mimic the real anatomical geometry of the human thyroid and which was filled with 99mTc solution (141.5 keV). The phantom was imaged from different angular projections, and Compton images were reconstructed using analytical and iterative image reconstruction codes. Based on the preliminary images of the thyroid phantom, the GRI+ system successfully visualised and distinguished the two thyroid lobes using one angle projection. Further analyses are warranted to determine whether Compton imaging is a promising modality for future nuclear medicine applications and whether it will significantly reduce the radiation dose delivered to patients. |
المرفقات
- https://uksacb.org/wp-content/uploads/Hamed-AlshammariPSD12.pdf
- https://uksacb.org/wp-content/uploads/ٍHamed-Paper.pdf
- https://uksacb.org/wp-content/uploads/IEEE2020_cert.pdf
- https://uksacb.org/wp-content/uploads/iop-2021cer.pdf
- https://uksacb.org/wp-content/uploads/iop2021poster.pdf
- https://uksacb.org/wp-content/uploads/PTCOG-2019.pdf
- https://uksacb.org/wp-content/uploads/PTCOG-2019-_cert.pdf
- https://uksacb.org/wp-content/uploads/UNTF2019-best-poster-award.pdf
- https://uksacb.org/wp-content/uploads/UNTF2019poster.pdf