Mohammed A. Alnafea

ABSTRACT Mammography, the standard method for breast cancer screening, misses many cancers, especially in women with dense breast. Whole-breast ultrasonography has been advocated to supplement digital mammography to improve outcomes. The main purpose of this study was to determine early breast tumour detection by assessing the performance of breast ultrasonography compared with X-ray mammography. We compared the performance and diagnostic yield of mammography alone versus ultrasound. The main objective was to investigate is ultrasound a viable method for early breast cancer detection. Breast Elastography phantom was used in this study as a method for comparison between both imaging modalities. We examine the detection capabilities of both imaging systems through visual visulisation of tumor and measureing the full-width at half maximum (FWHM). The imaging setup were optimized for small tumors using ultrasound and X-ray mammography imaging systems. In mammography, breast compression is applied to reduce the thickness of the breast phantom. The experimental results demonstrate the validity of using high-resolution ultrasound as complementry method for both screening and diagnostic mammography. For such phantom ultrasound is a more sensitive and accurate modality compared to digital mammography. Keywords: Mammography, US, Breast cancer; tumor detection

ABSTRACT Radiographic imaging is extremely valuable as a diagnostic tool in medicine, but ionizing radiation poses hazards for health-care providers as well as patients in health-care facilities (HCFs). Occupational radiation exposure can occur due to various human activities, including the use of radiation in medicine. Radiation exposure from diagnostic X-ray and computed tomography (CT) scan carry well-known potential risks. Personnel and radiation safety monitoring is an important safety precaution in the practice of radiography. The study aimed to assess the occupational radiation exposure and safety protection among medical staff in HCFs in the Eastern Province, Kingdom of Saudi Arabia (KSA). This study compares the occupational radiation dose levels for all radiation workers in King Faisal Medical Complex in Taif City of the kingdom of Saudi Arabia over four years. The occupational exposure was quantified using thermoluminescence dosimeters. The study results concludes that the occupational radiation doses to all workers during the four years period were below the limits set by the ICRP recommendations. The measured annual effective doses for workers were found to be 0.39 mSv. Keywords: Radiation Dose; Dose limits; Occupational exposure; Personal dosimetry; Radiology; TLD.

ABSTRACT The main aim of diagnostic radiology is to deliver high-quality diagnostic image information regarding anatomic detail or an ongoing physiological process within a patient's body, when such information cannot be provided by an alternate diagnostic method that does not require ionizing radiation. The major purpose of the quality assurance (QA) program of radiological practice optimization is to ensure enough clinical diagnostic information while exposing the patient to the least amount of radiation possible (as low as reasonably achievable ALARA principle) at the lowest cost. Implementing the QA program entails more than just completing legal requirements for quality control (QC) of X-ray and associated equipment and the regions where they are installed; it also entails making the best use of equipment, human, and material resources, as well as patient dosage monitoring during articular radiographic diagnostic procedures. The main objective of this study was to perform QC tests on stationary radiographic X-ray machines, installed in two hospitals of Riyadh city, Saudi Arabia. Based on the findings, kVp accuracy, kVp reproducibility, timer accuracy, timer reproducibility, exposure reproducibility, mA/timer linearity, and half-value layer were within the acceptable limits. Thus the result of the two X-Ray machines passed all the QC tests. Keywords: Diagnostic X-ray, Quality Assurance, Quality Control, X-ray meter, Radiology Device