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Pediatrics and children have higher radiosensitivity to ionizing radiation and radiogenic risks than adults due to their rapidly dividing tissues. This study explores the infant and children radiation doses during computed tomography (CT) abdomen and estimates the cancer risk from the procedure. In total, 87 were examined for CT enhanced abdominal examination. The abdominal CT scan with contrast was performed using a 128-slice multi slice CT (MSCT) scan. The mean, standard deviation, and range of patients' age (years) are 13 ± 4.5 (2–17). The mean and range of the air kerma length product (P KL (mGy.cm)) and volume CT air kerma index (C vol (mGy)) were 1740 (157.8–8440.3) (mGy.cm) and 9.8 (2.09–45.77) (mGy) per CT abdomen procedure, respectively. The mean and range of the effective dose (mSv) per procedure are 34 (3.14–176.8). The average radiogenic risk per CT procedure is one cancer incidence per 250 CT enhanced abdomen procedures. The mean and range of total irradiation even are 4.0 (2.0–8.0) times per procedure. The results of this study showed that child risk is high compared to other CT examinations. Therefore, patients' dose optimization and proper establishment of a diagnostic reference level (DRL) are necessary to preventing avoidable radiation risks. • Radiation dose were assessed for 87 abdomen Contrast enhanced Computed tomography (CECT) examinations. • The average radiogenic risk per CT procedure is one cancer incidence per 250 CT enhanced abdomen procedures. • The results of this study showed that child risk is high compared to other CT examinations. • The results obtained in this study are similar to those reported in previous studies. [ABSTRACT FROM AUTHOR]

Nuclear medicine diagnostic procedures such as positron emission tomography (PET) scans and hybrid imaging using a combination of PET and computed tomography (CT), commonly referred to as PET-CT scanning. Hybrid imaging, which allows accurate visualization of internal anatomical structure and the consequent physiological processes simultaneously, is extensively used in oncology and other departments. Nevertheless, this exposes patients and medical personnel in such departments to significant doses of ionizing radiation, especially in hybrid imaging, where two sources of radiation (the radiopharmaceutical infusion and the CT scanner) are used. This necessitates strict compliance with international guidelines and regulations on radiation protection. Recent reports showed that occupational staff exposure might exceed the annual dose limits. This study evaluated occupational exposure associated with diagnostic hybrid PET-CT imaging and the consequent risks. Twenty medical personnel: 5 physicists, ten technologists, two medical doctors, and three nurses are included in this study. The assessment includes measuring occupational ambient doses using calibrated optical stimulating-luminescent dosimeters (OSL) (Al2O3:C). These badges were read using an automatic OSL reader. The results, displayed as (mean ± standard deviation): (range) of the effective dose (mSv) for the different personnel, can be summarized as follows(mean standard deviation and range). Physicists 0.72 ± 0.14 (0.49–0.83) mSv in 2019 and 0.67 ± 0.07 (0.59–0.78) in 2020; technologist 1.4 ± 0.96 (0–3.27) mSv in 2019 and 1.395 ± 1.27 (0.64–4.36) mSv; medical doctors 0.445 ± 0.42 (0.15–0.74) mSv in 2019 and 0.70 ± 0.04 (0.67–0.73) in 2020; and nurses 1.38 ± 0.25 (1.21–1.66) mSv in 2019 and 1.41 ± 0.17 (1.23–1.55) in 2020. The tube voltage of the scanner used in this study had a constant value of 120 kVp for all patients. Staff working in PET or PET-CT departments receive significant doses from the radiopharmaceuticals and the energetic gamma rays from the CT scanners. Hence, optimizing the CT acquisition parameter is necessary to optimize the occupational doses and restrict them to acceptable dose limits. • Occupational ambient doses were quantified using calibrated (OSL (Al2O3:C) dosimeters. • Staff working in PET or PET-CT departments receive significant occupational doses. • Nurses received higher doses compared to other personnel. • Staff annual exposure is within the defined dose limits. [ABSTRACT FROM AUTHOR]

Staff occupational radiation exposure is limited to 20 mSv annually to preclude tissue reaction and lower risk of cancer effect. Staff occupational exposure arises during the preparation, injection, and scanning of the patients. Recent studies reported that nuclear medicine personnel might exceed the annual dose limit in high workload and poor radiation protection circumstances. Therefore, an accurate estimation of the annual dose limit is recommended. The goal of this research is to calculate the cumulative external effective dose (mSv) per year for nuclear medicine physicians, technologists, and nurses at SPECT/CT department. A total of 15 staff worked in the nuclear medicine department at King Saud Medical City (KSMC), Riyadh, Saudi Arabia were evaluated for the last six years. 99mTc is used more frequently for most of the patients. The procedures include renal, cardiac scintigraphy procedures. Staff dose was quantified using calibrated thermoluminecnt dosimeters (TLD-100) with an automatic TLD reader (Harshaw 6600). Exposure to ionizing radiation was evaluated in terms of deep doses (Hp(10) were evaluated. The overall average and standard deviation of the external doses for nuclear medicine physicians, technologists' and nurses were 1.8 ± 0.7, 1.9 ± 0.6, 2.0 ± 0.9, 2.2 ± 0.8, 6.0 ± 2.8, and 3.6 ± 1.3 for the years 2015,2016,2017,2018,2019, and 2020, respectively. Technologists and nurses received higher doses of compared to the nuclear medicine physicians. Technologists and nurses involved in radionuclide preparation, patients' injection, and image acquisition. Staff annual exposure is below the annual dose limits; however, this external dose is considered high compared to the current workload. • Staff annual effective dose was estimated at nuclear medicine department equipped with two SPECT/CT systems. • External effective dose in terms of Hp(10) was monitored for six consecutive years. • Occupational exposure was quantified with thermoluminecnt dosimeters (TLD-100). • Technologists and nurses received higher doses than the nuclear medicine physicians. • Staff annual radiation from external exposure is 50% below the annual dose limits. [ABSTRACT FROM AUTHOR]

This work investigates pediatric patients' radiation doses during multiphasic computed tomography (CT) abdomen procedures in six hospitals. A total of 58 (14 (24% females)) and 44 males (44, 76%) underwent CT single or multiphase procedures. A single phase and triple phase CT examination were carried a wide range of clinical indications, including renal and digestive systems pathologies. All procedures were performed at six radiology departments. Three departments are equipped with 16 slice CT machines, and the other three departments are equipped with 160, 128 and 16 slice CT machines. The overall 3rd quartile values for CTDI vol (mGy) and DLP (mGy.cm) were 8.6 ± 4.7 (mGy) and 1580 ± 594.64 (mGy.cm) per CT abdomen procedure. The current study indicates the need for dose optimization for pediatric patients by establishing proper imaging protocols based on the international guidelines. The variation in patients' doses is attributed to variation in the imaging protocols, scan length and number of phases performed per pediatric CT abdomen procedure. • Pediatric multiphasic CT abdomen procedures were performed at six radiology departments. • The radiology departments are equipped with 16, 64, 128 and 160 slice CT machines. • The increase in the scan length and number of phases exposed the patients to unnecessary radiation. • CT dose per procedure (DLP (mGy.cm) is higher compared to previous studies • Understanding of the technical factors that contribute to patient doses is essential in seeking patient's dose reduction. [ABSTRACT FROM AUTHOR]

The advanced image sensors installed on now-ubiquitous smartphones can be used to detect ionising radiation in addition to visible light. Radiation incidents on a smartphone camera's Complementary Metal Oxide Semiconductor (CMOS) sensor creates a signal which can be isolated from a visible light signal to turn the smartphone into a radiation detector. This work aims to report a detailed investigation of a well-reviewed smartphone application for radiation dosimetry that is available for popular smartphone devices under a calibration protocol that is typically used for the commercial calibration of radiation detectors. The iPhone 6s smartphone, which has a CMOS camera sensor, was used in this study. Black tape was utilized to block visible light. The Radioactivity counter app developed by Rolf-Dieter Klein and available on Apple's App Store was installed on the device and tested using a calibrated radioactive source, calibration concrete pads with a range of known concentrations of radioactive elements, and in direct sunlight. The smartphone CMOS sensor is sensitive to radiation doses as low as 10 µGy/h, with a linear dose response and an angular dependence. The RadioactivityCounter app is limited in that it requires 4–10 min to offer a stable measurement. The precision of the measurement is also affected by heat and a smartphone's battery level. Although the smartphone is not as accurate as a conventional detector, it is useful enough to detect radiation before the radiation reaches hazardous levels. It can also be used for personal dose assessments and as an alarm for the presence of high radiation levels. [ABSTRACT FROM AUTHOR]

Reflecting upon the influence of current diagnostic imaging radiation protection practices in Sudan, a sampling evaluation is made of administered activity across all five of the nuclear medicine departments in the country. Data were collected in respect of 423 patients, administered nuclide activities showing accord with international levels. For administered activity, four of the five departments use International Atomic Energy Agency (IAEA) Basic Safety Standard protocols, the other adopting UK Administration of Radioactive Substances Advisory Committee (ARSAC) practice. For national nuclear medicine diagnostic purposes overwhelming use is made of 99mTc. Thyroid and parathyroid scans account for 43% of the 423 investigations, while whole body bone and renal scans provide for the imaging needs of the respective 34% and 23% remaining patients. Of the acquired images, in excess of 80% of these were planar. The mean and standard deviation effective dose values were 2.26 ± 0.61, 4.70 ± 0.77 and 1.03 ± 0.29 mSv, for thyroid, bone and dynamic renal scans respectively, comparable with that of previous studies. While department designs are observed to comply with radiation protection regulations, the personal monitoring service is much less satisfactory, data frequently being found to be absent in all five departments. Moreover, only 60% of the medical physicists have been in receipt of regular radiation protection training, while other medical staff within the departments have not benefited from the relevant training at all, including physicians, nurses and nuclear medicine technologists. None have received regular specific medical checks. Accordingly, the Sudanese Nuclear & Radiological Regulatory Authority are now playing a major role in development of nuclear medicine practice and associated safety requirements, seeking accord with the principle of ALARA. Physician/medical physicist cooperation is needed in addressing optimization of radiation dose and image quality, also radiation protection awareness and training, as well as in medical surveillance. • Diagnostic imaging radiation protection in Sudan nuclear medicine practice evaluated. • Survey of administered activity, imaging protocol and protection in Sudan nuclear medicine. • Department designs accord with protection regulations but not in personal monitoring. • 60% of the medical physicists have been in receipt of regular radiation protection training. [ABSTRACT FROM AUTHOR]

Occupational radiation exposure can occur due to various human activities, including the use of radiation in medicine. Occupationally exposed personnel surpassing 7.4 millions, and respresent the biggest single group of employees who are exposed to artificial radiation sources at work. This study compares the occupational radiation dose levels for 145 workers in four different hospitals located in the Aseer region in Saudi Arabia. The occupational exposure was quantified using thermoluminescence dosimeters (TLD-100). The levels of annual occupational exposures in targeted hospitals were calculated and compared with the levels of the international atomic energy agency (IAEA) Safety Standards. An average yearly cumulative dose for the two consecutive years. The average, highest and lowest resulted occupational doses under examination in this work is 1.42, 3.9 mSv and 0.72 for workers in various diagnostic radiology procedures. The resulted annual effective dose were within the IAEA approved yearly dose limit for occupational exposure of workers over 18, which is 20 mSv. Staff should be monitored on a regular basis, according to current practice, because their annual exposure may surpass 15% of the annual effective doses. • Annual occupational dose (Hp(10) were evaluated at four diagnostic radiology department. • Staff doses represent approximately 15% of the annual effective dose. • Students and trainees should be monitored on a regular basis, according to current practice. • Occupational exposure is comparable with the most previously published studies. [ABSTRACT FROM AUTHOR]

Computed tomography is widely used for planar imaging. Previous studies showed that CR systems involve higher patient radiation doses compared to digital systems. Therefore, assessing the patient's dose and CR system performance is necessary to ensure that patients received minimal dose with the highest possible image quality. The study was performed at three medical diagnostic centers in Sudan: Medical Corps Hospital (MCH), Advance Diagnostic Center (ADC), and Advance Medical Center (AMC). The following tools were used in this study: Tape measure, Adhesive tape, 1.5 mm copper filtration (>10 × 10 cm), TO 20 threshold contrast test object, Resolution test object (e.g., Huttner 18), MI geometry test object or lead ruler, Contact mish, Piranha (semiconductor detector), Small lead or copper block (∼5 × 5 cm), and Steel ruler, to do a different type of tests (Dark Noise, Erasure cycle efficiency, Sensitivity Index calibration, Sensitivity Index consistency, Uniformity, Scaling errors, Blurring, Limiting spatial Resolution, Threshold, and Laser beam Function. Entrance surface air kerma (ESAK (mGy) was calculated from patient exposure parameters using DosCal software for three imaging modalities. A total of 199 patients were examined (112 chest X rays, 77 lumbar spine). The mean and standard deviation (sd) for patients ESAK (mGy) were 2.56 ± 0.1 mGy and 1.6 mGy for the Anteroposterior (AP) and lateral projections for the lumbar spine, respectively. The mean and sd for the patient's chest doses were 0.1 ± 0.01 for the chest X-ray procedures. The three medical diagnostic centers' CR system performance was evaluated and found that all of the three centers have good CR system functions. All the centers satisfy all the criteria of acceptable visual tests. CR's image quality and sensitivity were evaluated, and the CR image is good because it has good contrast and resolution. All the CR system available in the medical centers and upgraded from old X-ray systems to new systems, has been found to work well. The patient's doses were comparable for the chest X-ray procedures, while patients' doses from the lumbar spine showed variation up to 2 folds due to the variation in patients' weight and X-ray machine setting. Patients dose optimization is recommended to ensure the patients received a minimal dose while obtaining the diagnostic findings. • Computed radiography system performance were evaluated at three hospitals in Sudan. • Patients ESAK (mGy) was quantified for chest X rays and lumber spine procedures. • CR systems performance was acceptable and within the predefined limits. • The ESAK (mGy) was lower compared to previous published studies. [ABSTRACT FROM AUTHOR]

Breast cancer is a common malignancy for females (25% of female cancers) and also has low incidence in males. It was estimated that 1% of all breast malignancies occur in males with mortality rate about 20%, with annual increase in incidence. Risk factors include age, family history, exposure to ionizing radiation and high estrogen and low of androgens hormones level. Diagnosis and screening are challenging due to limiting effectiveness of breast cancer screening. Therefore, patients may expose to ionizing radiation that may contribute in breast cancer incidence in males. In literature, limited studies were published regarding radiation exposure for males during mammography. The objective of this research is to quantify patient doses during male mammogram and to estimate the projected radiogenic risk during the procedure. In total, 42 male patients were undergone mammogram for breast cancer diagnosis during two consecutive years. The mean and range of patient age (years) is 45 (23–80). The mean and standard deviation (SD) of the peak tube potential and tube current time product are 28.64 ± 2. and 149 ± 35.1, respectively. The mean, and range of patients' entrance surface air kerma (ESAK, mGy) per single breast procedure was 5.3 (0.47–27.5). Male patient's received comparable radiation dose per mammogram compared to female procedures. With increasing incidence of male breast cancer, proper guidelines are necessary for the mammographic procedure are necessary to reduce unnecessary radiation doses and radiogenic risk. • Average glandular doses were quantified for 42 male patients' mammograms. • The radiogenic risk for male procedure is low compared to other procedures. • Elimination of the radiation exposure for young male and girls is recommended. • Males received comparable dose to females mammography procedure. [ABSTRACT FROM AUTHOR]

In comparison to adults and paediatric are more sensitive to ionizing radiation exposure. Computed tomography (CT) is now the dominant source of medical radiologic tests for patients, accounting for more than 70% of total doses to the general public. Paediatric CT brain scans (with and without contrast) are routinely performed for a variety of clinical reasons. As a result, this parameter must be calculated in order to determine relative radiation risk. The goal of this study is to assess the radiation risk to children during CT brain diagnostic procedures. Three hundred fifty three child patients' radiation risk doses were assessed over the course of a year. The mean and ranged of the children's radiation doses were 40.6 ± 8.8 (27.8–45.8) CTDIvol (mGy) and 850 ± 230 (568.1–1126.4) DLP (mGy.cm) for the brain with contrast medium. For CT brain without contrast, the patients' doses were 40.9 ± 9.4 (14.27–64.07) CTDIvol (mGy), and 866.1 ± 289.3 (203.6–2484.9) DLP (mGy.cm). The characteristics related to the radiation dose were retrieved from the scan protocol generated by the CT system by the participating physicians after each procedure. Furthermore, optimizing the CT acquisition parameter is critical for increasing the benefit while lowering the procedure's radiogenic risk. The patients' radiation dose is comparable with the most previously published studies and international diagnostic reference levels (DRLs). Radiation dose optimization is recommended due to high sensitivity of the paediatric patients to ionizing radiation. • Pediatric doses radiation risk were assessed to children during CT brain diagnostic procedures. • The patients' doses with CT brain angiography is twice the dose without contrast medium. • Radiosensitive organs (eye lens and thyroid) must be shielded to reduce the radiogenic risk probability. • The patients' radiation dose is comparable with the most previously published studies. [ABSTRACT FROM AUTHOR]

The uptake of Fluorine-18 fluoro-deoxy-glucose (18F-FDG) in tumors is assessed using the Standardized Uptake Values (SUVs). These values are usually normalized for the body weight of the patients (SUVbw). However, reported literature revealed an overestimation of uptake in obese patients who suffer from higher body fat content with low uptake of the 18F-FDG. Normalization of 18F-FDG uptake using body surface area (SUVbsa) may present a solution to overestimating uptake. The current study aims to evaluate uptake values of FDG in the tumor versus liver using two standardizing parameters: weight and area. Data for liver and tumor uptake were collected from 40 patients who underwent FDG-PET scans. Regarding uptake for the liver, the standardization using body weight, SUVbw, was calculated as tissue concentration over activity injected per body weight. Using surface area, SUVbsa used activity injected per surface area rather than weigh in the denominator. The correlation was performed to determine the association between the factors of age, body mass index (BMI), and liver SUVmax. The SUVbsa ranged between 0.79 and 5.8, and SUVbw ranged between 3.11 and 28.36. The range, as well as the standard deviation, were by far more in SUVbw than SUVbsa and the independence of the values on the size of patients proves that the latter is a preferable standardization method. • The uptake of 18F-FDG in tumors is assessed using the Standardized Uptake Values (SUVs). • Data for uptake in the liver and tumour were collected from 40 patients underwent FDG-PET scans. • Standardization using surface area, SUV bsa used activity injected per surface area rather than weigh in the denominator. • Normalization of 18F-FDG uptake using SUV bsa present a solution to the overestimation of uptake. [ABSTRACT FROM AUTHOR]

The purpose the current work were to assess the radiation exposure given to patients during percutaneous coronary interventions (PCI), pacemaker (PM) and coronary angiography (CA), procedures. In total, 419 procedures were carried out in 4 specialized hospitals. Calibrated Kerma area product meters were used to quantify the patient doses. Effective dose was extrapolated using the national radiological protection board (NRPB) software program. The mean KAP (Gy.cm2) per procedure were 8.6, 6.2 and 5.6 for PCI, PM, and CA procedures, respectively. While in that order, e mean and Entrance Surface Air Kerma (ESAK, mGy) per procedure were 705.9,509, and 464.7 for PCI, PM, and CA. Patients' doses is below the level of the deterministic effects and the effective dose per procedure is low. Patients radiation doses is lowest compared to the previous studies. • Patients' radiation doses were monitored during cardiac catheterization procedures. • The patient's doses were measured using a Kerma area product meter (KAP). • The variances in radiation doses incurred during PCI were greater than the variance in doses incurred in CA and pacemaker. • DRL values derived in this study were comparable with values reported in international literature. [ABSTRACT FROM AUTHOR]

With 75.4% of the effective doses from imaging estimated to result from computed tomography (CT), it is the leading source of medical radiation. This important observation links with a further estimate that some 2% of all cancers are a result of medical imaging exposures. Acknowledging justification and optimization to be key towards preventing unnecessary radiation exposure, present study aims to investigate radiation exposures reduction for patients undergoing multiphase CT abdomen. Study was made of 111 CT examinations, use being made of two imaging protocols. Of these cases, 55 (49.5%) were obtained using a standard imaging protocol, the remainder being studied using the pure 3D SureExposure™ low-dose technique to obtain a complete abdomen multi-phase examination. Image quality was the subject of blind analysis by two experienced radiologists. For the standard imaging protocol, the mean and standard deviation for CTDI vol and DLP were respectively 7.2 ± 2.3 mGy and 1325 ± 605 mGy cm. For the pure 3D SureExposure™ low-dose technique the respective values were 5.2 ± 1.6 mGy and 812 ± 157 mGy cm. With an achieved mean dose reduction of up to 48%, use of the low dose techniques offers appreciable potential for dose saving without affecting the image quality. • Study was made of 111 CT abdomen multi-phase examinations, use being made of two imaging protocols. • 3D sure-exposure low-dose technique was used to obtain a complete abdomen multi-phase examination. • Image quality was the subject of blind analysis by two experienced radiologists. • Reduction of radiation dose up to 48% was achieved without affecting the image quality. [ABSTRACT FROM AUTHOR]