Medical Imaging Technology

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Browsing Medical Imaging Technology by Author "Doaa Housni Ali Bani Odeh"

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    An Advanced Approach to Reconstruct CT Images from limited-angle projections, reducing radiation dose and tube load.
    (Al-Quds University, 2023-12-12) Doaa Housni Ali Bani Odeh; دعاء حسني علي بني عودة
    Concerns regarding ionizing radiation doses to individuals and patients have arisen as a result of the remarkable advancements in computed tomography (CT) technology and applications over the last ten years, so Computed tomography (CT) scanners and CT exams have increased continuously. Researchers aim to minimize ionizing radiation dose via introducing new CT protocols and providing diagnostic CT images with lower radiation doses to patient. Nevertheless, these investigations have challenges: reducing the radiation dose results in decreased image quality, which might occasionally be non-diagnostic. In This study, the researcher aims to investigate the possibility of forming a CT brain image from a limited number of projections at a projection angle of less than 180 degrees While maintaining image quality based on the ALARA principle and decreasing radiation dose. then determine if the images match the quality criteria of Brain CT. This effort spanned from January 2023 to September 2023. The process of reconstructing CT scan images from limited angle projections is critical and requires strict adherence to the ALARA principle. This principle is designed to minimize radiation exposure while maintaining image quality. Our study utilized filter back-projection (FBP) and algebraic iterative reconstruction (IR) algorithms to reconstruct brain CT images from 500 projection lines with a 100 x 100 and 200 x 200 matrix size. In addition to researching the effect of the reconstruction angle on image quality, two degrees were taken at an angle of 90 and 45 degrees. The images were evaluated for image quality criteria by 10 expert medical imaging technicians and 2 radiologists and specific evaluations were given. Then, a simple descriptive statistical analysis was conducted, including calculating percentages for expert medical imaging technicians and radiologists evaluations and p-values. By combining the results of a MATLAB 2021 functions with the insights of a radiologist, we can produce high-quality images that decrease radiation dose and tube load. Our findings reveal that the algebraic method is superior to the filter back-projection in preserving image quality when utilizing limited-angle projections. In addition to the Statistical t-test (P<.001), which confirms the existence of statistical differences between the two algorithms. With a percentage of 41%, or a moderate scale, the IR algorithm matches quality requirements better. Conversely, the FBP exhibits a proportion of < 25%, signifying a weak scale. Based on the percentages of evaluation, we can confirm that the size of the Matrix 200 x 200 is superior to the size of the Matrix 100 x 100, as it formed a percentage of 36.25%, which is equivalent to a moderate scale. In addition, the reconstruction angle of 90 provides better quality and its percentage was 41.75%, equivalent to a moderate scale. So the IR algorithm at 90 degree with 500 projection only provides images that match the quality criteria for brain CT. while FBP fails to provide any meaningful insights when working with angles of 45 and 90 degrees.