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Screening mammography is considered to be the most effective means for the early detection of breast cancer. However, epidemiological studies suggest that longitudinal exposure to screening mammography may raise breast cancer radiation-induced risk, which begs the need for optimization and internal auditing. The present work aims to establish a comprehensive well-structured Diagnostic Reference Level (DRL) system that can be confidently used to highlight healthcare centers in need of urgent action, as well as cases exceeding the dose notification level. Screening mammographies from a total of 2048 women who underwent screening mammography at seven different healthcare centers were collected and retrospectively analyzed. The typical DRL for each healthcare center was established and defined as per (A) bilateral image view (left craniocaudal (LCC), right craniocaudal (RCC), left mediolateral oblique (LMLO), and right mediolateral oblique (RMLO)) and (B) structured compressed breast thickness (CBT) criteria. Following this, the local DRL value was established per the bilateral image views for each CBT group. Screening mammography data from a total of 8877 images were used to build this comprehensive DRL system (LCC: 2163, RCC: 2206, LMLO: 2288, and RMLO: 2220). CBTs were classified into eight groups of <20 mm, 20-29 mm, 30-39 mm, 40-49 mm, 50-59 mm, 60-69 mm, 70-79 mm, 80-89 mm, and 90-110 mm. Using the Kruskal-Wallis test, significant dose differences were observed between all seven healthcare centers offering screening mammography. The local DRL values defined per bilateral image views for the CBT group 60-69 mm were (1.24 LCC, 1.23 RCC, 1.34 LMLO, and 1.32 RMLO) mGy. The local DRL defined per bilateral image view for a specific CBT highlighted at least one healthcare center in need of optimization. Such comprehensive DRL system is efficient, easy to use, and very clinically effective.

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Neutron capture therapy (NCT) is a radiotherapeutic technique that is designed to utilize the neutron capture reaction and damage the tumor cells through the energy release from the reaction. Nuclear reactors are typically utilized in this therapy because of the high neutron fluence rate that can be achieved. There has been minimal work to evaluate the effectiveness of neutron generators in NCT. This work presents the preliminary simulation results of utilizing of a deuterium-deuterium generator in boron neutron capture therapy. MCNP 6.1 was used to model the detailed geometry of the neutron generator and the phantom. Neutron moderators and photon shielding were used to optimize the neutron fluence rate in the tumor and decrease the photon dose in the phantom respectively. The study showed that a good localization of the neutron dose can be achieved in the tumor area with a reduction of the photon dose in the surrounding areas.

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Monitoring drinking water, including bottled water, is imperative to safeguarding public health especially where bottled water consumption is high like in the United Arab Emirates (UAE). In this study, radionuclide activity levels of Tritium (3H) and Potassium (40K) were assessed in various brands of bottled water marketed in UAE. Activity level data was used to calculate the annual effective doses (Ed) for different age groups, and the excess lifetime cancer risk (ELCR) for adult males and females in the UAE population. Activity levels for both radionuclides were below the allowable maximum guideline values specified by local and international standards. Calculated total age dependent ingestion doses revealed that adults and lactation age groups received the highest effective ingestion doses. Adult males exhibited a higher ELCR for both isotopes, compared to females. Nonetheless, total radioactive dose for each water brand (0.91-1.47 µSv/yr) as well as for each population group were well below the recommended annual reference dose level of 100 µSv set by World Health Organization. Therefore, bottled water in the UAE is safe from the radiological aspect for investigated radionuclides, and poses no significant radiological exposure and health risk to the public.

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AIM: Excessive visceral adiposity is a major risk factor for developing insulin resistance and systemic low-grade inflammation. Ramadan diurnal fasting (RDF) is a religious ritual practiced by more than one billion Muslim throughout the world. It has been considered as one of the most common types of complementary and integrative health practices. The aim of this study is to examine the impact of RDF on visceral adiposity, circulating adipokines and glucoregulatory markers in patients with overweight or obesity. METHODS: Overweight and obese subjects (n = 61; 23 men and 38 women) were included in the study. Body weight, visceral fat tissue area (measured by 3D-MRI), glucoregulatory factors, serum adipokines concentrations, dietary intake, and physical activity were assessed one week before and at the end of the lunar month of Ramadan. RESULTS: From baseline, body weight and visceral fat tissue area serum total cholesterol, triglycerides, HDL-cholesterol, and systolic blood pressure significantly decreased (P < 0.05 for each) at the end of Ramadan. The serum levels of adiponectin, IL-6, TNF-α, and IGF-1 significantly decreased (P < 0.05 for each), but serum visfatin, leptin, apelin, IL-10, and IL-10/IL-6 ratio significantly increased (P < 0.05 for each) at the end of Ramadan. Changes in visceral adiposity significantly correlated with changes in plasma glucose (r = 0.4, P < 0.5) and resistin (r = 0.44, P < 0.001) at the end of Ramadan. CONCLUSION: RDF lowers visceral adiposity, body weight and variably affects adipokines without adversely affecting markers of glucose homeostasis in individuals with overweight or obesity.

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The aim of this study is to calculate total cruising route effective doses using three commonly used algorithm codes CARI-6, EPCARD and SIEVERT. Further, the impact of flight cruising duration, altitude and latitude on the estimated effective doses will also be investigated. A total of 24 commercial UAE flight data were collected and retrospectively analysed. CARI-6, EPCARD and SIEVERT codes were used to estimate the total route effective doses per single trip of different destinations including USA, Europe, South Africa, Asia and Australia. Aircraft crew effective doses were shown to significantly increase with flying altitude. A strong significant correlation (0.6469; p < 0.05) was obtained between flight duration and the estimated effective doses, while a moderate insignificant correlation (0.3899; p > 0.05) was obtained with flying altitude for all 24 flights using CARI-6. For flights with the same latitude and duration, all codes gave total effective doses within experimental uncertainties.

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In radiotherapy the efficacy of medical imaging is central to the selection and delineation of target volume. Of note is that target volume is intended to be larger than tumour volume, including a geometric margin that accounts for the possible uncertainties in patient set-up. However this reduces potential tissue sparing, irradiating not only the target but also normal tissue. Additionally, features of the object that appear in the 2D image display may be influenced by the appropriate window level selection. This is especially critical for target volume delineation in radiotherapy. The present work seeks to assess the effect of window level selection on feature size in CT, MR and PET images, use being made of a NEMA body phantom and ProSoma 3D simulation software. In general, the window level produced discrepancies of up to +/-2 mm in all imaging modalities.

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Multi-modality imaging is involved in almost all oncology applications from diagnosis through treatment planning and follow-up. Commercial image fusion software packages are becoming available but require comprehensive evaluation to ensure reliability of fusion and the underpinning registration algorithm. This is especially critical for target volume delineation in radiotherapy. The present work seeks to assess such accuracy for a number of available registration methods. A National Electrical Manufacturers Association (NEMA) body phantom was used in evaluating computer tomography (CT), magnetic resonance (MR) and PET images. In addition, discussion is provided concerning the choice and geometry of fiducial markers in phantom studies and the effect of window level on target size, in particular in regard to the application of multimodality imaging in treatment planning. In general, the accuracy of fusion of multi-modality images was within 0.5-1.5mm of actual feature diameters and <2 ml volume of actual values, particularly in CT images.

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