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Precise patient radiation dosimetry during theranostic procedures allows clinicians to tailor therapeutic procedures to each patient. Organ dose measurement aids in adjustment of the administered activity or number of treatment cycles to maximize tumor cell destruction while minimizing damage to healthy tissues. This study was aimed at quantifying patient organ doses during Lu-177 DOTATATE and Lu-177 PSMA theranostic procedures. Nine patients underwent Lu-177 radionuclide therapy, usually four cycles with 6–8 GBq administered activity per cycle. The typical dose is 7.5 GBq as a fixed activity. Using quantitative dosimetry, physicians can estimate the next dose cycle according to patient condition. The average dose per activity for critical organs were low, at 1.76, 1.96, 0.25, 0.5, and 2.43 mSv/MBq for the right kidney, left kidney, liver bladder, and spleen, respectively. The doses for the left and right kidneys, liver, urinary bladder, and spleen were lower than those in previously published studies. Wide variations were observed in patient organ doses for Lu-177 DOTATATE and Lu-177 PSMA procedures. Further studies are recommended to ensure organ safety during theransotic procedures, to minimize the radiogenic risks to healthy organs. • Organ doses during Lu-177 DOTATATE and Lu-177 PSMA theranostic procedures were estimated. • The lu177 radionuclide therapy usually consists of 4 cycles with 6–8 GBq dose for each cycle. • The spleen accumulates the highest portion of the Lu-177 DOTATAE radiopharmaceutical. • Sensitive organ doses are lower compared to the previously published studies. • The low organ dose will enable clinicians to maximize therapeutic outcome. [ABSTRACT FROM AUTHOR]

In addition to generalised of bone loss and a higher fracture risk, rheumatoid arthritis (RA) causes periarticular bone erosions. Improvements in bone density/erosion and turnover may not go hand in hand with a positive clinical response to biological anti-inflammatory drugs assesed by disease activity score 28 (DAS28) in RA patients. This study aimed to understand how biologic anti-inflammatory drugs affect bone density, erosion, and turnover in RA patients. We examined bone mineral density (BMD) and bone turnover biomarkers. The study population consisted of 62 RA patients, 49 (79%) of whom were female and 13 (21%) of whom were male. The patients ranged in age from 40 to 79 years old. The patients' BMD was measured using a DEXA scan, and their plasma levels of bone turnover biomarkers CTX and osteocalcin were quantified utilizing an ELISA. BMD of the hip and lumbar spine in responder patients rose after therapy by 0.001g/cm2 (0.11 percent, p0.001 vs. before treatment) and 0.0396g/cm2 (3.96 percent, p0.001 vs. before treatment), respectively. Clinically non-responder patients' DAS28 revealed minor reductions in hip BMD values of −0.008g/cm2 (−0.78 percent, p0.001 vs. before therapy), as well as an improvement in lumbar spine BMD of 0.03g/cm2 (3.03 percent, p0.001 vs. before treatment). After 12 weeks of therapy, the CTX levels in responder patients dropped from 164 125 pg/ml to 131 129 pg/ml. Osteocalcin levels in non-responder patients increased substantially from 11.6 ng/ml to 14.9 ng/ml after 12 weeks of therapy compared to baseline (p = 0.01). Treatment with biologic anti-inflammatory medicines decreases widespread bone loss in RA patients' hip and lumbar spine. The beneficial effects of therapy on BMD were not associated with changes in disease activity of RA patients. Changes in plasma levels of bone turnover biomarkers such as sCTX and osteocalcin confirmed the treatment's beneficial effects. • The biologic anti-inflammatory drugs effect was assessed using DEXA scan. • Changes in BMD of patients assessed before and after treatment. • The study revealed significant increase in BMD due to biologic anti-TNF medicines. • The beneficial impact could or might not be related to changes in DAS28 values. [ABSTRACT FROM AUTHOR]

Medical exposure of the general population due to radiological investigations is the foremost source of all artificial ionising radiation. Here, we focus on a particular diagnostic radiological procedure, as only limited data are published with regard to radiation measurements during urethrograpic imaging. Specifically, this work seeks to estimate patient and occupational effective doses during urethrographic procedures at three radiology hospitals. Both staff and patient X-ray exposure levels were calculated in terms of entrance surface air kerma (ESAK), obtained by means of lithium fluoride thermoluminescent dosimeters (TLD-100(LiF:Mg:Cu.P)) for 243 urethrographic examinations. Patient radiation effective doses per procedure were estimated using conversion factors obtained from the use of Public Health England computer software. In units of mGy, the median and range of ESAK per examination were found to be 10.8 (3.6–26.2), 7.0 (0.2–32.3), and 24.3 (9.0–32.0) in Hospitals A, B, and C, respectively. The overall mean and range of staff doses (in µGy) were found to be 310 (4.0–1750) per procedure. With the exception of hospital C, the present evaluations of radiation dose have been found to be similar to those of previously published research. The wide range of patient and staff doses illustrate the need for radiation dose optimisation. [ABSTRACT FROM AUTHOR]

The aims of the present work were to quantify radiation doses arises from patients' exposure in mammographic X-ray imaging procedures and to estimate the radiation induced cancer risk. Sixty patients were evaluated using a calibrated digital mammography unit at King Khaled Hospital and Prince Sultan Center, Alkharj, Saudi Arabia. The average patient age (years) was 44.4 ± 10 (26–69). The average and range of exposure parameters were 29.1 ± 1.9 (24.0–33.0) and 78.4 ± 17.5 (28.0–173.0) for X-ray tube potential (kVp) and current multiplied by the exposure time (s) (mAs), respectively. The MGD (mGy) per single projection for craniocaudal (CC), Medio lateral oblique (MLO) and lateromedial (LM) was 1.02 ± 0.2 (0.4–1.8), 1.1 ± 0.3 (0.5–1.8), 1.1 ± 0.3 (0.5–1.9) per procedure, in that order. The average cancer risk per projection is 177 per million procedures. The cancer risk is significant during multiple image acquisition. The study revealed that 80% of the procedures with normal findings. However, precise justification is required especially for young patients. [ABSTRACT FROM AUTHOR]

Abstract Eye lenses lie within the radiation field during computed tomography (CT) procedures of the brain. Therefore, patients are at risk of forming eye lens opacity when exposures exceed the threshold for such onset. The purpose of this study was to estimate the eye lens equivalent and radiation effective doses during CT procedures of the brain, facial bones, and paranasal sinuses. A total of 85 patients were examined using a 16-detector CT machine. The organ and surface dose received by specific radiosensitive organs was carried out using software from the National Radiological Protection Board (NRPB). The overall mean patient doses were as follows: CTDI vol , 45.7 ± 15.6 mGy for brain; and 7.6 mSv for the eye lens. The mean eye lens equivalent dose per CT procedure was 11.5 mSv, 4.5 mSv, and 6.7 mSv for the brain, paranasal sinuses, and facial bones, respectively. The radiation risk per procedure equates to 1 cancer case per 11 × 10−3 procedures. The study shows there to be great need for improving the imaging protocol and for continuous training of staff. Dose reduction techniques in brain CT are required, eye lens irradiations potentially generating lens opacities. Highlights • CT doses to the lens of the eyes of patients evaluated. • Evaluated for Multislice CT units, in terms of CTDI vol and DLP. • 85 of Patient evaluation made in Saudi Hospital operating a 16 and 128 slice facility. • For brain sinuses and facial bone procedures, mean equivalent of 11.5, 4.5 and 6.7 mGy per CT reported. [ABSTRACT FROM AUTHOR]

Abstract Renal imaging (scintigraphy, intravenous urography (IVU) and computed tomography urography (CTU)) are non-invasive procedures that provide information essential in the diagnosis and treatment of renal disorders. The importance of these procedures notwithstanding, radiation exposure to the different tissues and organs could result in diverse reaction possibilities of varying severity. Accordingly, patient dose measurement of such exposures represent an essential step in seeking radiation dose optimization. Present study seeks to quantify effective doses for paediatric patients undergoing renal scintigraphy, IVU and CTU procedures using technetium-99m-diethylene-triamine-pentaacetic acid. Patients population consist of 116 patients (68 boys and 48 girls) were investigated using an Orbiter 37 single-head gamma camera, a digital imaging system and a dual-slice CT detector unit. Patient effective doses were estimated, administered activity ranging between 37.0 and 129.5 MBq per procedure. The mean effective dose and range (in mSv) for renal scintigraphy, CT Urography and IVU procedures were 1.0, 0.98 and 0.6 mSv per procedure respectively. The associated radiation risk estimates per procedure range between 80 and 130 cancers per one million procedures. Patients undergoing renal scintigraphy and CTU procedures received comparable doses such that if CT parameters are optimized this then allows the referring physician to consider the best diagnostic outcome regardless of modality selected. Highlights • Dose to paediatric patients undergoing radiographic renal imaging calculated. • Effective dose & radiation risk estimated for 99mTc (DTPA), CT urography, intravenous urography. • The least dose to paediatric patients found to be from intravenous urography. • Patients undergoing renal scintigraphy and CTU procedures found to receive comparable doses. [ABSTRACT FROM AUTHOR]

Abstract With associated cure rates in excess of 90%, targeted 131I radioactive iodine therapy has clearly improved thyroid cancer survival. Thus said, potential radiation risks to staff represent a particular concern, current study seeking to determine the radiation exposure of staff from 131I patients during hospitalization, also estimating accumulated dose and related risk to staff during preparation of the radioactive iodine. In present study made over the three-month period 1st February to 1st May 2017, a total of 69 patient treatments were investigated (comprising a cohort of 46 females and 23 males), this being a patient treatment load typically reflective of the workload at the particular centre for such treatments. The patients were administered sodium iodide 131I, retained in capsules containing activities ranging from 370 to 5550 MBq at the time of calibration, radioiodine activity depends on many factors such as gender, clinical indication, body mass index and age. The staff radiation dose arising from each patient treatment was measured on three consecutive days subsequent to capsule administration. In units of µSv, the mean and dose-rates range at distances from the patients of 5 cm, 1 m and 2 m were 209 ± 73 (165–294), 6.8 ± 2 (5.3–9.5) and 0.9 ± 0.3 (0.7–1.2). The annual dose (also measured in units of µSv), based on annual records of doses, for medical physicists, technologists and nurses were 604, 680 and 1000 µSv respectively. In regard to current practice and workload, staff exposures were all found to be below the annual dose limit for radiation workers. Highlights • Occupational and ambient dose measured during 131I treatment. • Occupational exposure obtained using electronic personal monitoring device. • During patient isolation period nurses exposed to higher dose compared to other staff. • For current practice and workload, staff exposures all below annual limit for radiation workers. [ABSTRACT FROM AUTHOR]

A pacemaker, which is used for heart resynchronization with electrical impulses, is used to manage many clinical conditions. Recently, the frequency of pacemaker implantation procedures has increased to more than 50% worldwide. During this procedure, patients can be exposed to excessive radiation exposure. Wide range of doses has been reported in previous studies, suggesting that optimization of this procedure has not been fulfilled yet. The current study evaluated patient radiation exposure during cardiac pacemaker procedures and quantified the patient effective dose. A total of 145 procedures were performed for five pacemaker procedures (VVI, VVIR, VVD, VVDR, and DDDR) at two hospitals. Patient doses were measured using the kerma-area product meter. Effective doses were estimated using software based on Monte Carlo simulation from the National Radiological Protection Board (NRPB, now The Health Protection Agency). The effective dose values were used to estimate cancer risk from the pacemaker procedure. Patient demographic data and exposure parameters for fluoroscopy and radiography were quantified. The mean patient doses ± SD per procedure (Gy cm 2 ) for VVI, VVIR, VVD, VVDR, and DDDR were 1.52 ± 0.13 (1.43–1.61), 3.28 ± 2.34 (0.29–8.73), 3.04 ± 1.67 (1.57–4.86), 6.04 ± 2.326 3.29–8.58), and 8.8 ± 3.6 (4.5–26.20), respectively. The overall patient effective dose was 1.1 mSv per procedure. It is obvious that the DDDR procedure exposed patients to the highest radiation dose. Patient dose variation can be attributed to procedure type, exposure parameter settings, and fluoroscopy time. The results of this study showed that patient doses during different pacemaker procedures are lower compared to previous reported values. Patient risk from pacemaker procedure is low, compared to other cardiac interventional procedures. Patients' exposures were mainly influenced by the type of procedures and the clinical indication. [ABSTRACT FROM AUTHOR]

Butylatedhydroxytoluene (BHT) rods represent a potential dosimeter in radiation processing, with readout via electron paramagnetic resonance (EPR) spectroscopy. Among the possible sources of uncertainty are those associated with the performance of the dosimetric medium and the conditions under which measurements are made, including sampling and environmental conditions. Present study makes estimate of the uncertainties, investigating physical response in different resonance regions. BHT, a white crystalline solid with a melting point of between 70–73 °C, was investigated using 60 Co gamma irradiation over the dose range 0.1–100 kGy. The intensity of the EPR signal increases linearly in the range 0.1–35 kGy, the uncertainty budget for high doses being 3.3% at the 2σ confidence level. The rod form represents an excellent alternative dosimeter for high level dosimetry, of small uncertainty compared to powder form. [ABSTRACT FROM AUTHOR]

Ionizing radiation exposure is associated with eye lens opacities and cataracts. Radiation workers with heavy workloads and poor protection measures are at risk for vision impairment or cataracts if suitable protection measures are not implemented. The aim of this study was to measure and evaluate the occupational radiation exposure in a nuclear medicine (NM) department. The annual average effective doses (Hp[10] and Hp[0.07]) were measured using calibrated thermos-luminescent dosimeters (TLDs; MCP-N [LiF:Mg,Cu,P]). Five categories of staff (hot lab staff, PET physicians, NM physicians, technologists, and nurses) were included. The average annual eye dose (Hp[3]) for NM staff, based on measurements for a typical yearly workload of >7000 patients, was 4.5 mSv. The annual whole body radiation (Hp[10]) and skin doses (Hp[0.07]) were 4.0 and 120 mSv, respectively. The measured Hp(3), Hp(10), and Hp(0.07) doses for all NM staff categories were below the dose limits described in ICRP 2014 in light of the current practice. The results provide baseline data for staff exposure in NM in Kuwait. Radiation dose optimization measures are recommended to reduce NM staff exposure to its minimal value. [ABSTRACT FROM AUTHOR]

Computed tomography angiography (CTA) has become the most valuable imaging modality for the diagnosis of blood vessel diseases; however, patients are exposed to high radiation doses and the probability of cancer and other biological effects is increased. The objectives of this study were to measure the patient radiation dose during a CTA procedure and to estimate the radiation dose and biological effects. The study was conducted in two radiology departments equipped with 64-slice CT machines (Aquilion) calibrated according to international protocols. A total of 152 patients underwent brain, lower limb, chest, abdomen, and pelvis examinations. The effective radiation dose was estimated using ImPACT scan software. Cancer and biological risks were estimated using the International Commission on Radiological Protection (ICRP) conversion factors. The mean patient dose value per procedure (dose length product [DLP], mGy·cm) for all examinations was 437.8 ± 166, 568.8 ± 194, 516.0 ± 228, 581.8 ± 175, and 1082.9 ± 290 for the lower limbs, pelvis, abdomen, chest, and cerebral, respectively. The lens of the eye, uterus, and ovaries received high radiation doses compared to thyroid and testis. The overall patient risk per CTA procedure ranged between 15 and 36 cancer risks per 1 million procedures. Patient risk from CTA procedures is high during neck and abdomen procedures. Special concern should be provided to the lens of the eye and thyroid during brain CTA procedures. Patient dose reduction is an important consideration; thus, staff should optimize the radiation dose during CTA procedures. [ABSTRACT FROM AUTHOR]

Hypoxic solid tumours have a poor prognosis and little curability when treated with radiation therapy. Consequently, evaluation of oxygen levels in solid tumours is required to increase the proportion of patients who experience treatment success. The three gamma annihilation of radioiodine −124 (124I) during positron emission tomography (PET) can be used to diagnose hypoxia in solid tumours. 124I is the focus of this study, which intends to evaluate its role in detecting hypoxia in samples with various oxygen concentrations. At King Faisal Specialist Hospital and Research Center (KFSH&RC) in Saudi Arabia, a system was set up to monitor the yield of the three gamma using High Purity Germanium (HPGe) radiation detectors. These detectors, operating under the same conditions as one another, were used to record the triple coincidence. 5.0 mL of water was treated with oxygen and nitrogen gases to produce oxygenated and deoxygenated samples. In measuring the relative three gamma to two gamma yield, the peak to valley and peak to peak methods were compared. The three gamma coincidence was increased by 23% in deoxygenated sample compared to oxygenated one. The results of this study illustrated that the three gamma detection was increased in deoxygenated samples (hypoxia). • 3 γ yield in three samples with varied degrees of oxygenation was assessed. • Peak-valley & peak-peak methods were compared in measuring the relative 3γ yield. • The 3 γ yield coincidence was increased by 23% in deoxygenated sample. • 124I could be used as a non-invasive technique for 3γ PET hypoxia assessment. [ABSTRACT FROM AUTHOR]

Positron emission tomography (PET) is widely used for medical imaging to investigate the spatial distribution of pharmaceuticals labelled with positron emitters in patients. This study investigated the potential to perform three gamma (3γ) imaging based on ortho-positronium annihilation for assessment of tumour hypoxia. Evaluation of Oxygen deficiency is necessary to assure successful treatment. It was reported that PET imaging with a radioisotope could be used as molecular markers to detect tumour hypoxia. This method is based on the physics of 2γ annihilation. However, the 3γ annihilation yield is governed by the positronium formation as well as in quenching rates which could be used as a new PET molecular imaging modality. This study provides a method for the preparation of biological samples with different oxygen concentrations as well as developing a configuration system for the determination of the 3γ yield using high-purity germanium (HPGe) detectors to investigate the measurement of 3γ imaging. This study compares the decay rates in oxygen and nitrogen saturated samples of water and serum, the results show that 3γ annihilation with different oxygen concentrations could illustrate the oxygenation in biological models. Even though many diverse disciplines are involved in this work, the advantages and disadvantages of each possible technique have yet to be concisely summarized. This study sets out the background to the clinical applications of the 3γ PET technique and compares this non-invasive method with existing oxygen measurement devices. • Three gamma (3γ) annihilation was used for the assessment of hypoxia. • Oxygen levels were assessed in different biological samples. • High-purity germanium (HPGe) detectors were used to investigate 3γ annihilation. [ABSTRACT FROM AUTHOR]

The various technological advancements in computed tomography (CT) have resulted in remarkable growth in the use of CT imaging in clinical practice, not the least of which has been its establishment as the most valuable imaging examination for the assessment of cardiovascular system disorders. The objective of this study was to assess the effective radiation dose and radiation risk for patients during cardiac CT procedures, based on studies from four different hospitals equipped with 128 slice CT equipment. A total of eighty-three patients were investigated in this study with different clinical indications. Effective doses were also calculated using software based on Monte Carlo simulation. The mean patient age (years), weight (kg), and body mass index (BMI (kg/m2)) were 49 ± 11, 82 ± 12, and 31 ± 6, respectively. The results of the study revealed that the tube voltage (kVp) and tube current-exposure time product (mAs) ranged between 100 to 140 and 50 to 840 respectively. The overall average patient dose values for the volume CT dose index [(CTDI vol), in mGy)] and dose length product (DLP) (in mGy·cm) were 34.8 ± 15 (3.7–117.0) and 383.8 ± 354 (46.0–3277.0) respectively. The average effective dose (mSv) was 15.2 ± 8 (1.2–61.8). The radiation dose values showed wide variation between different hospitals and even within the same hospital. The results indicate the need to optimize radiation dose and to establish diagnostic reference levels (DRLs) for patients undergoing coronary computed tomography angiography (CCTA), also to harmonize the imaging protocols to ensure reduced radiation risk. • Effective radiation dose was assessed for patients during coronary computed tomography angiography (CCTA) procedure. • The dose was quantified at four different hospitals equipped with 128 slices CT equipment. • The use of effective dose to compare doses with previous studies under estimate the radiation dose. • Radiation doses are imaging protocol dependent and varied among different departments. • The results indicates the necessity to harmonies the imaging protocols to reduce the preventable radiation risk. [ABSTRACT FROM AUTHOR]

In interventional radiology attendant staff can be exposed to significant doses from the radiation scattered from the patient, giving rise to heterogeneous energy distribution, exposure occurring over extended periods of time. Protection of staff is a prime concern, also including reducing the risk of carcinogenesis. With only limited published studies available, as in for instance in regard to lens opacifications, further evaluation of staff exposures and assessment of radiation protection techniques and measures are crucial. Present study has sought to evaluate staff radiation exposure in a radiology department that performs interventional procedures. Annual occupational exposures were obtained for 32 personnel (6 females and 26 males) in a radiology department at a tertiary hospital. Personal dose equivalent H p (d) was measured in terms of H p (0.07) (shallow dose) and H p (10) (deep dose). The measurements were made over a period of two consecutive years, 2017 and 2018, use being made of TLD-100 thermoluminescent dosimeters. In units of mSv, the corresponding average annual dose equivalent and range for H p (10) and H p (0.07) were 4.6 ± 7.0 (0.1–25.5) and 5.1 ± 7.3 (0.1–25.5). Notably, 16% of staff received doses that were greater than the annual dose limit. Since H p (10) offers a conservative evaluation of effective dose, evaluation of the working environment is necessary in seeking to ensure dose values remain below annual dose limits. • Occupational exposure was measured at interventional radiology department. • Personal dose equivalent (H p (d) were measured in terms of H p (0.07) (shallow dose) and H p (10) (deep dose) were evaluated. • Staff exposures were measured using TLD-100 thermoluminecent dosimeters. • 16% of the staff received doses that were greater than the annual dose limit. • Variation in staff dose is due to workload and type of the procedure. [ABSTRACT FROM AUTHOR]

During the preparation of radioisotopes, during their administration and during patient imaging nuclear medicine personnel are routinely exposed to ionising radiation. With radiation risks increasing with dose, safety assessment is required in seeking to ensure practice complies with international guidelines and dose limits. A particular aim herein is to measure staff exposures during certain molecular imaging procedures including through use of positron emission tomography with computed tomography (PET/CT) and single photon emission computed tomography (SPECT) procedures. Over a one-year period occupational doses were monitored for 30 nuclear medicine personnel at King Faisal Specialist Hospital and Research Center (KFSH&RC) in Riyadh. Dose equivalent values were measured in terms of Hp (10) (deep dose) and Hp (0.07) (skin dose), extremity doses also being measured via ring dosimeters. The measurements were made using calibrated thermoluminescent dosimeters, type LiF:Mg, Ti (TLD-100). In mSv, the respective mean annual dose and range for H p (10), H p (0.07) and extremities were 3.05 ± 2.1 (0.23–0.91), 3.15 ± 2.2 (0.1–9.1) and 28.25 (0.1–298.0). In all cases, extremity dose values were well below the annual dose limit (500 mSv). Nevertheless, with personnel doses varying significantly, careful assessment of working conditions is recommended in efforts to ensure occupational exposures remain below annual dose limits. • Occupational doses were monitored for 30 nuclear medicine personnel over one year using thermoluminescent dosimeters. • The dose was quantified in terms of Hp (10) and Hp (0.07) and extremity doses. • Occupational doses were below the annual dose limits for whole body and extremities. • Careful assessment of working conditions are recommended in seeking to reduce gender differences in occupational exposures. [ABSTRACT FROM AUTHOR]

This study investigated the paediatric patient doses received in Saudi Arabia during CT examinations of the brain, abdomen and chest. The study includes data from a total of 59 patients from three hospitals, the mean age and age range of the paediatric cases being 5.10 (0.01–13) years, mean weight and weight range 20 (3–40) kg. The range of DLP (mGy.cm) per procedure was 113–995, 54–1244 and 30.0–190.0 for brain, abdomen and chest procedures, respectively. DRLs were proposed for all three procedures, the values being comparable with European Guidelines on Quality Criteria for Computed Tomography. The study has shown there to be a need in Saudi Arabia to refer to such criteria as well as a need for continuous training of staff in radiation dose optimisation concepts. • Radiation dose was measured for paediatric patients during CT procedures. • Patient doses comparable with European guidelines for paediatric cases. • Local Diagnostic Reference Levels proposed. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the annual occupational radiation exposure of technologists during PET/CT imaging in 2020 and 2021. Eleven nuclear medicine technologists were monitored at the PET/CT department. The personal dose equivalents (PDEs) for staff members, measured in terms of Hp (10) and Hp (0.07), were assessed annually, considering both deep and surface doses. PDEs were quantified using a thermoluminescent detector (LiF:Mg:Ti)). The average and range of PDEs and extremity doses (mSv) for the technologists were as follows: 4.5 (0.1–13.4) for Hp (10), 4.63 (0.1–13.9) for Hp (0.07), and 2.5 (0.2–17.5) for extremity, respectively. The results indicated that staff members are exposed to high-energy gamma rays while preparing radiopharmaceuticals, injections, and image acquisition. Therefore, proper handling of radiopharmaceuticals and patient management during the acquisition of parameters are crucial for maintaining the occupational dose within the defined limit. • Occupational doses were measured using calibrated Thermo-luminescent dosimeters (TLD). • The annual effective dose for PET-CT personnel were found to be below the recommended dose limits. • Staff are exposed to avoidable radiation doses. [ABSTRACT FROM AUTHOR]

Abstract Cardiac catheterizations (CC) represent a set of interventional procedure used in the diagnosis and treatment of coronary arteries diseases. Whereas interventional procedures perhaps represent only some 12% of all radiological procedures they nevertheless contribute about 48% of the total collective dose worldwide. In a Sudanese based study, the objectives of present work have been to evaluate patient radiation dose and to estimate effective doses and cancer risks for three types of cardiac catheterization procedure. Radiation doses and the associated radiation risks have been evaluated for a total of 346 patients undergoing treatments for a range of clinical indications, including 187 Diagnostic Coronary Angiographic (DCA) procedures (54%), 118 Percutaneous Coronary Interventions (PCI) (34.1%) and 41 Pacemaker (PM) procedures (11.9%)). The respective effective dose ranges were 4.0- to 59.3 mSv, 11.4- to 175 mSv and 7.2- to 51.5 mSv. None of the present patient cohort developed tissue reactions, deterministic effects clearly being anathema in diagnostic radiological practice. With optimization of patient doses being fundamental to best practice, and with it an associated mitigation of stochastic risk, not least in regard to patients of younger age facing the greatest risk, there is particular concern regarding training and experience of radiographic staff, as results show. Highlights • Radiation dose survey for patients undergoing certain cardiac catheterization procedures. • Patient dose was measured using calibrated kerma area product (KAP) meter. • In complex procedures, patient may receive a higher doses that may lead to tissue reaction (erythema). • A radiation dose registry was initiated to monitor patient received a dose above 1.5 Gy for erythema detection. [ABSTRACT FROM AUTHOR]

This work using a borosilicate glass medium seeks to detect photoneutrons generated by a medical linear accelerator. The studies involved an Elekta Infiniti accelerator located in the Oncology Centre, Medical City, Riyadh, the neutrons resulting from interactions at above-threshold therapeutic photon energies. The borosilicate detectors were produced from microscope glass slides of nominal thickness 1.0 mm, the latter made into square segments of area 0.6 × 0.6 cm2, a size capable of being accommodated within the planchette of the thermoluminescent (TLD) Reader (Harshaw 600). With some 4% boron in the coverslip glass and the abundance of 10B being 19.8%, thermalised neutrons 10B(n,α)7Li interactions offer a cross-section that can achieve a value as large as 3837 b. Apart from interactions in boron, of additional note is that 2H(γ,n)1H and 9Be(γ,n)8Be are two further photoneutron reactions, giving rise to particularly low threshold energies at 2.226 and 1.666 MeV, respectively. The presence of natural carbon in the present borosilicate samples has been measured to be 1.3%. Accordingly, with the abundance of 13C in natural carbon being 1.109% this would appear to be of very little interest herein. Moreover, compositional measurements made on the borosilicate coverslip glass indicates 9.40 Na. The induced activity in the glass falls to some 25% 30 h post-irradiation, a delay time beyond which readout can subsequently be conducted. • Borosilicate glass media for neutron sensing was developed. • Photoneutron was generated using an Elekta Infiniti linear accelerator beams. • Neutron activation of nuclides within the expanse of the beam should be considered. [ABSTRACT FROM AUTHOR]

The objectives of this study are to assess pediatric radiation exposure in certain barium studies and to quantify the organ and effective doses and radiation risk resultant from patients' irradiation. A total of 69 pediatric barium studies for upper and lower gastrointestinal tract. Patients' radiation dose was quantified in terms of Entrance surface air kerma (ESAKs) using exposure parameters and DosCal software. Organ and effective doses ( E ) were extrapolated using national Radiological Protection Board software (NRPB-R279). The mean ± (SD) and the range of patient doses per procedure were 3.7 ± 0.4 (1.0–13.0) mGy, 7.4 ± 1.7(5.5–8.0) mGy and 1.4 ± 0.9 (0.5–3.6) mGy for barium meal, swallow and enema, respectively. The mean effective doses were 0.3 ± 0.03 (0.08–1.1) mSv, 0.2 ± 1.6 (0.44–0.7) mSv and 0.3 ± 0.9 (0.1–0.8) mSv at the same order. The radiation dose were higher compared to previous studies. Therefore, pediatrics are exposed to avoidable radiation exposure. Certain optimization measures are recommended along with establishing national diagnostic reference level (DRL) to reduce the radiation risk. [ABSTRACT FROM AUTHOR]

In the modern clinical practice of diagnostic radiology there is a growing demand for radiation dosimetry, it also being recognized that with increasing use of X-ray examinations additional population dose will result, accompanied by an additional albeit low potential for genetic consequences. At the doses typical of diagnostic radiology there is also a low statistical risk for cancer induction; in adhering to best practice, to be also implied is a low but non-negligible potential for deterministic sensitive organ responses, including in regard to the skin and eyes. Risk reduction is important, in line with the principle of ALARP, both in regard to staff and patients alike; for the latter modern practice is usually guided by Dose Reference Levels (DRL) while for the former and members of the public, legislated controls (supported by safe working practices) pertain. As such, effective, reliable and accurate means of dosimetry are required in support of these actions. Recent studies have shown that Ge-doped-silica glass fibres offer several advantages over the well-established phosphor-based TL dosimeters (TLD), including excellent sensitivity at diagnostic doses as demonstrated herein, low fading, good reproducibility and re-usability, as well as representing a water impervious, robust dosimetric system. In addition, these silica-based fibres show good linearity over a wide dynamic range of dose and dose-rate and are directionally independent. In the present study, we investigate tailor made doped-silica glass thermoluminescence (TL) for applications in medical diagnostic imaging dosimetry. The aim is to develop a dosimeter of sensitivity greater than that of the commonly used LiF (Mg,Ti) phosphor. We examine the ability of such doped glass media to detect the typically low levels of radiation in diagnostic applications (from fractions of a mGy through to several mGy or more), including, mammography and dental radiology, use being made of x-ray tubes located at the Royal Surrey County Hospital. We further examine dose-linearity, energy response and fading. [ABSTRACT FROM AUTHOR]

There is apaucity of data concerning irradiation effects on the extracellular matrix and on organised tissues. Examples of such research are cited as are some of the limiting factors towards obtaining meaningful results. This would engender a range of research towards further improving the quality of life, most pointedly of those receiving radiotherapy. As cancer survivor rates increase, survivors are more likely to experience side effects of radiotherapy. This study examines the effects of radiotherapy doses on the extracellular matrix as hyaluronic acid (HA) and pericardium. [ABSTRACT FROM AUTHOR]

Endoscopic retrograde cholangiopancreatography (ERCP) is an invasive technique that has been used for over 30 years in the diagnosis and management of pancreaticobiliary disorders. The objectives of this study were to evaluate the patient entrance surface air kerma doses (ESAK) and estimate the organ and effective doses during ERCP in three hospitals in Khartoum. A total of 55 patients were examined in three hospitals in Khartoum state, Sudan. Calibrated thermoluinescent dosimeters (TLD) were used to measure patients' ESAK. Organ and effective doses were estimated using National Radiological Protection Board (NRPB) software. The overall mean of ESAK for all ERCP procedures was 42.4 mGy. The mean patient ESAK in Fedail (A), Soba (B) and Ibn sena (C) hospitals were 26.7 mGy, 26.0 mGy and 72.4 mGy, respectively. The effective doses in three hospitals were 1.60, 1.56 and 2.67 mSv in that order and the overall mean effective dose was 1.94 mSv. Patient radiation doses vary widely among the hospitals. Patient ESAK is low compared to previous studies in the light of the current practice. Patient dose was decreased significantly in the last two decades. [ABSTRACT FROM AUTHOR]

Abstract: The potential of incorporating three-quanta annihilation into positron emission tomography (PET) to detect local tissue chemistry was investigated using the GAMMASPHERE facility, which features a spherical array of 110 Compton-suppressed high-purity germanium (HPGe) detectors. Fluoro-2-deoxyglucose (FDG) containing was introduced into 11 samples of haemolysed blood, serum, cell concentrate and whole blood, some of which had been either oxygenated or deoxygenated. The relative three-quanta yield was estimated from the reduced counts in the full-energy photopeak at 511keV. Compton-suppression produced larger effects in the calculations than time-gating, suggesting its importance for this method of estimation. The relative three-quanta yields were found to vary as much as 11% between the samples. This level of sensitivity to different biological samples commends three-quanta annihilation for molecular imaging. [Copyright &y& Elsevier]

Monitoring of staff's radiation exposure in medicine is an important radiation protection task. This study aimed to measure the staff doses in the nuclear medicine (NM) and interventional cardiology (IC) departments in Sudan and assess whether the measured doses fall within the recommended radiation protection standards. 37 members of staff involved in the NM and IC procedures were monitored using electronic personal dosimeters (EPDs). In IC, the average monthly Hp (10) values ranged from 30.0 to 38.9 µSv (to cardiologists), from 3.6 to 13.5 µSv (to nurses), and from 3.5 to 8.9 µSv (to technologists). The annual effective dose ranged from 1.95 to 2.53 mSv (to cardiologists), from 0.23 to 0.88 mSv (to nurses), and from 0.23 to 0.56 mSv (to technologists). In NM, the monthly Hp (10) values ranged between 83.0 and 84.0 µSv (to nurses), 38.8 and 54.0 µSv (to pharmacists), 16.9 and 70.2 µSv (to technologists), 40.2 and 76.6 µSv (to physicists). The annual effective doses ranged from 0.91 to 0.92 mSv (to nurses), 0.43–0.59 mSv (to pharmacists), 0.19–0.77 mSv (to technologists), and 0.44–0.84 mSv (to physicists). The estimated doses fall below the recommended annual dose limit. However, the lack of a radiation surveillance program and use of occupational exposure control tools are of concern in both the IC and NM departments. • Dose to staff were studied in nuclear medicine (NM) and interventional cardiology (IC) in Sudan. • In IC procedures, the estimated annual effective doses were: 1.95–2.53 mSv varied. • In NM procedures, the estimated annual effective doses were: 0.19–0.92 mSv varied. • Doses are below the annual dose limit but occupational exposure control tools are lacking. • The data are important in promoting radiation protection good practices at workplaces. [ABSTRACT FROM AUTHOR]

Ultrasound personnel can be occupationally exposed to ionizing radiation from radioisotopes during ultrasonography imaging of patients who received radioactive material. Thus, radiation safety assessment is required to ensure that the ultrasonography physicians practices conform with the international guidelines and that dose limits are not exceeded. This study aimed to measure staff exposure during ultrasound investigations of such patients who received radioactive material in molecular imaging procedures such positron emission tomography (PET) and single photon emission computed tomography (SPECT). Occupational doses, in terms of Hp (10) (deep dose), Hp (0.07) (skin dose) and ambient dose were monstered using calibrated thermos-luminescent dosimeters (TLDs) to ensure occupational doses exposures for the ultrasonographers over 1 year at King Faisal Specialist Hospital and Research Center in Riyadh, Saudi Arabia. The overall mean of Hp(10), Hp(0.07) for an annual occupational dose of 0.4 mSv and ambient dose (mSv) were (M) in ultrasound room, Hp(10) of 1.7 mSv and Hp(0.07) of 1.72 mSv in the Hot Lab, and Hp(10) of 0.4 mSv and Hp(0.07) of 0.02 mSv in the Stress Room. Occupational exposure was below the annual dose limits (20.0 mSv) for all practitioners, as well the extremities dose was below the annual dose limits of 500 mSv. In conclusion, since staff exposure which highly depends on radioisotope characteristics and protection measures can vary significantly for different personnel, continuous serial careful assessment of working conditions is recommended to ensure occupational doses exposures remain below annual limits. • Sonographers' exposure was assessed for patients who received the radioactive material. • Occupational dose equivalent was measured in terms of Hp (10) and Hp (0.07). • Staff exposure depends on the administered activity and protection measures. • The occupational doses are below the annual limits. [ABSTRACT FROM AUTHOR]

Abstract Patient effective doses and the associated radiation risks arising from particular computed tomography (CT) imaging procedures are assessed. The objectives of this research are to measure radiation doses for patients and to quantify the radiogenic risks from CT brain and chest procedures. Patient data were collected from five calibrated CT modality machines in Saudi Arabia. The results are from a study of a total of 60 patients examined during CT procedures using the calibrated CT units. For CT brain and chest, the mean patient effective doses were 1.9 mSv (with a range of 0.6–2.5 mSv) and 7.4 mSv (with a range of 0.5–34.8 mSv) respectively. The radiogenic risk to patients ranged from between 10−5 and 10−4 per procedure. With 65% of the CT procedure cases diagnosed as normal, this prompts re-evaluation of the referral criteria. The establishment of diagnostic reference levels (DRL) and implementation of radiation dose optimisation measures would further help reduce doses to optimal values. Highlights • Radiation dose survey for patients undergoing CT brain and chest examinations in Saudi Arabia. • Breast dose found to be high in CT chest examination, clear justification criteria being crucial. • Wide discrepancy between patient doses underlines need for establishing dose reference levels. • Dose delivered to patients found to be greater than reported in previous studies. [ABSTRACT FROM AUTHOR]

Abstract Patient radiation dose and image quality are primary issues in the conduct of nuclear medicine (NM) procedures. A range of protocols are currently used in image acquisition and analysis of quality control (QC) tests, with National Electrical Manufacturers Association (NEMA) methods and protocols widely accepted in providing an accurate description, measurement and report of γ-camera performance parameters. However, no standard software is available for image analysis. Present study compares vendor QC software analysis and three types of software freely downloadable from the internet: NMQC, NM Toolkit and ImageJ-NM Toolkit software. These were used for image analysis of QC tests of γ-cameras based on NEMA protocols including non-uniformity evaluation. Ten non-uniformity QC images were obtained using a dual head γ-camera installed in Trieste General Hospital and then analyzed. Excel analysis was used as the baseline calculation for the non-uniformity test according to NEMA procedures. The results of non-uniformity analysis showed good agreement between the independent types of software and Excel calculations (the average differences were 0.3%, 2.9%, 1.3% and 1.6% for the Useful Field of View (UFOV) integral, UFOV differential, Central Field of View (CFOV) integral and CFOV differential, respectively), while significant differences were detected following analysis using the company QC software when compared with Excel analysis (the average differences were 14.6%, 20.7%, 25.7% and 31.9% for the UFOV integral, UFOV differential, CFOV integral and CFOV differential, respectively). Compared to use of Excel calculations use of NMQC software was found to be in close accord. Variation in results obtained using the three types of software and γ-camera QC software was due to the use of different pixel sizes. It is important to conduct independent analyses tests in addition to using the vendor QC software in order to determine the differences between values. Highlights • Comparison of vendor QC analysis software with that freely downloadable from the internet. • Software for image analysis based on NEMA protocols including non-uniformity evaluation. • Significant differences between Excel and vendor software due to different pixel sizes used in analysis. [ABSTRACT FROM AUTHOR]

In thermoluminescence (TL) material dopant concentration has an important effect on their characteristics as a “radiation-sensor”. The study investigates dosimetric properties of four different concentration (4 mol%, 5 mol%, 7 mol% and 25 mol%) tailor-made Ge-doped silica fibers. The intention is to seek development of alternative TL materials that offer exceptional advantages over existing passive systems of dosimetry, including improved spatial resolution, a water impervious nature and low cost. Photon beams (6 MV and 10 MV) from a clinical linear accelerator were used for irradiation of the fiber samples over radiation therapy doses, ranging from 0.5 Gy to 8 Gy. SEM-EDX analysis was also performed to investigate the homogeneity of distribution of Ge dopant concentration from the fiber samples. The results of measurement were also compared with two of the more commonly used standard TLDs, TLD-100 (LiF: Mg,Ti-7.5% 6 LiF) and TLD-700 (( 7 LiF: Mg,Ti-99.9% 7 LiF) chips respectively. The TL intensity of the fiber samples was found to strongly depend on Ge dopant concentration, with samples showing enhanced TL yields with decreasing Ge dopant concentration. 4 mol% Ge-doped silica fiber provided the greatest response whereas the 25 mol% samples showed the least, indicative of the well-known concentration quenching effects All fiber TLDs provided linear dose response over the delivered radiotherapy dose-range, the fibers also showing a weak dependence on photon beam energies in comparing the TL yields at 6 and 10 MV. The fading behavior of the different concentration Ge doped TLD-materials were also measured over a period of thirty (30) days subsequent to irradiation. The relative sensitivity of the samples with respect to standard TLD-100 were found to be 0.37, 0.26, 0.13 and 0.02 in respect of the 4, 5, 7 and 25 mol% fibers. The primary dosimetry peak, which was by far the most prominent of any other feature covered by the glow curve, was found to be around 244 °C using the most sensitive silica fiber. The study is expected to pave the way in making more comprehensive investigations aimed at defining improved TL response fiber samples. [ABSTRACT FROM AUTHOR]

In many countries diagnostic medical exposures typically account for a very large fraction of the collective effective dose that can be assigned to anthropological sources and activities. This in part flags up the question of whether sufficient steps are being taken in regard to potential dose saving from such medical services. As a first step, one needs to survey doses to compare against those of best practice. The present study has sought evaluation of the radiation protection status and patient doses for certain key radiological procedures in four film-based radiology departments within Sudan. The radiation exposure survey, carried out using a survey meter and quality control test tools, involved a total of 299 patients their examinations being carried out at one or other of these four departments. The entrance surface air kerma (ESAK) was determined from exposure settings using DosCal software and an Unfors -Xi-meter. The mean ESAK for x-ray examination of the chest was 0.30±0.1 mGy, for the skull it was 0.96±0.7 mGy, for the abdomen 0.85±0.01 mGy, for spinal procedures 1.30±0.6 mGy and for procedures involving the limbs it was 0.43±0.3 mGy. Ambient dose-rates in the reception area, at the closed door of the x-ray room, recorded instantaneous values of up to 100 µSv/h. In regard to protection, the associated levels were found to be acceptable in three of the four departments, corrective action being required for one department, regular quality control also being recommended. [ABSTRACT FROM AUTHOR]

This work addresses purpose-made thermoluminescence dosimeters (TLD) based on doped silica fibres and sol–gel nanoparticles, produced via Modified Chemical Vapour Deposition (MCVD) and wet chemistry techniques respectively. These seek to improve upon the versatility offered by conventional phosphor-based TLD forms such as that of doped LiF. Fabrication and irradiation-dependent factors are seen to produce defects of differing origin, influencing the luminescence of the media. In coming to a close, we illustrate the utility of Ge-doped silica media for ionizing radiation dosimetry, first showing results from gamma-irradiated Ag-decorated nanoparticles, in the particular instance pointing to an extended dynamic range of dose. For the fibres, at radiotherapy dose levels, we show high spatial resolution (0.1 mm) depth-dose results for proton irradiations. For novel microstructured fibres (photonic crystal fibres, PCFs) we show first results from a study of undisturbed and technologically modified naturally occurring radioactivity environments, measuring doses of some 10 s of μGy over a period of several months. [ABSTRACT FROM AUTHOR]

Using six types of tailor-made doped optical fibres, we carry out thermoluminescent (TL) studies of X-rays, investigating the TL yield for doses from 20 mGy through to 50 Gy. Dosimetric parameters were investigated for nominal 8 wt% Ge doped fibres that in two cases were co-doped, using B in one case and Br in the other. A comparative measurement of surface analysis has also been made for non-annealed and annealed capillary fibres, use being made of X-ray Photoelectron Spectroscopy (XPS) analysis. Comparison was made with the conventional TL phosphor LiF in the form of the proprietary product TLD-100, including dose response and glow curves investigated for X-rays generated at 60 kVp over a dose range from 2 cGy to 50 Gy. The energy response of the fibres was also performed for X-rays generated at peak accelerating potentials of 80 kVp, 140 kVp, 250 kVp and 6 MV photons for an absorbed dose of 2 Gy. Present results show the samples to be suitable for use as TL dosimeters, with good linearity of response and a simple glow curve (simple trap) distribution. It has been established that the TL performance of an irradiated fibre is not only influenced by radiation parameters such as energy, dose-rate and total dose but also the type of fibre. [ABSTRACT FROM AUTHOR]

The goal of the current research was to define the impact of individual characteristics on the response of osteoporosis patients to bisphosphonate medication, as well as the influence of gender on changes in the bone mineral density (BMD).The DXA scan was used to assess a group of 647 osteoporosis patients (533 females and 114 males) who visited the St Bartholomew's Hospitals and Royal London osteoporosis clinics. All male subjects received statistically substantial increases in BMD relative to baseline values after two years of therapy. When compared to prior therapy, men's BMD of the lumbar spine (LS) and hip joint (HJ) rose by 0.057 g/cm2 (6.9%, p0.001) and 0.021 g/cm2 (2.48 percent, p0.001), respectively.. Female patients had BMD changes of 0.028 g/cm2 (3.58 percent, p0.001 vs. prior therapy) and −0.006 g/cm2 (−0.78 percent, p0.001 vs. before treatment) in the lumbar spine and hip, respectively. Male patients exhibited a greater increase in BMD than female patients due to ovarian failure and significant oestrogen loss, which speeds up bone resorption by 90% following menopause, according the research findings. • Bone mineral density (BMD) in the diagnosis and follow-up of patients with osteoporosis was investigated. • The DEXA scan was used to assess a group of 647 osteoporosis patients. • Afro-Caribbean patients have higher baseline BMD in the lumbar spine and hip than Caucasian. • Age, gender, ancestral origin, and smoking behaviours all affect osteoporosis treatment. [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 objectives of this study were to measure the entrance surface air kerma (ESAK) and the effective doses in pediatric patients undergoing micturating cystourethrography (MCU) procedures. The ESAK was determined using calibrated thermoluminescent dosimeters (TLD- GR 200 A) in 167 pediatric patients. The patient population was categorized into three groups according to age (0–5 years (group 1), 6–10 years (group 2) and 11–15 years (group 3)). The mean ESAK±SD and range (mGy) resulting from a MCU procedure was estimated to be 2.2±0.5 (0.8–9.2), 2.48±0.6 (0.9–8.1) and 3.90±0.6 (1.1–10.3) for group 1, 2 and 3, respectively. The mean effective dose was between 0.03 and 0.4 mSv per procedure for the pediatric population. Pediatric patients were exposed to avoidable radiation doses because no gonad shields were used. [ABSTRACT FROM AUTHOR]

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]

The purpose of this study was to investigate the two dimensional (2D) and three dimensional (3D) radiotherapy dosimetric properties of PRESAGE® dosimeter using an in-house optical computed tomography (OCT) imaging system known as 3DmicroHD-OCT. Dosimetric properties for verification of intensity-modulated radiation therapy (IMRT) treatment technique were studied including dose linearity, dose integration, dose rate dependence and the percentage depth dose analysis. Nine cylindrical PRESAGE® of 5 cm diameter × 5 cm height were irradiated at 6 MV photon beam with different field geometry for the dose range of 0.1–15 Gy. We also irradiated PRESAGE® in the cuvette for UV–Vis analysis for the same dose range to verify the optical density value measured by the 3DmicroHD-OCT imaging system. The irradiation was repeated with EBT film dosimetry for the 2D analysis validation. The study shows that the optical density change increases as dose deposition increases on PRESAGE®, with R2 value better than 0.988. The same response was also recorded when multiple beam was integrated for the dose range investigated. The dose linearity result is consistent with the results obtained from UV–Vis spectrometry. It was also found that the dose rate variation does not affect the optical density change over the dose range investigated. PDD analysis of the PRESAGE® dosimeter investigated shows a good agreement with the ion chamber measurement. In summary, the study shows accurate 3D and 2D measurements of PRESAGE® and EBT film dosimeter were obtained using the 3DmicroHD-OCT imaging system. It shows potential for intensity-modulated radiation therapy (IMRT) treatment verification. • The prototype 3DmicroHD-OCT system provides 3D optical imaging for PRESAGE® dosimeter. • Multidimensional (2D and 3D) dose analysis was validated against EBT film. • The 3D dose integrated is linear from 0.1 to 15 Gy and independent of dose rates. [ABSTRACT FROM AUTHOR]

The aims of this study were to measure the patients’ entrance surface air kerma doses (ESAK), effective doses and to compare practices between different hospitals in Sudan. ESAK were measured for patient using calibrated thermo luminance dosimeters (TLDs, GR200A). Effective doses were estimated using National radiological Protection Board (NRPB) software. This study was conducted in five radiological departments: Two Teaching Hospitals (A and D), two private hospitals (B and C) and one University Hospital (E). The mean ESAK was 20.1 mGy, 28.9 mGy, 13.6 mGy, 17.5 mGy, 35.7 mGy for hospitals A, B, C, D, and E, respectively. The mean effective dose was 2.4 mSv, 3.5 mSv, 1.6 mSv, 2.1 mSv and 4.3 mSv in the same order. The study showed wide variations in the ESDs with three of the hospitals having values above the internationally reported values. [ABSTRACT FROM AUTHOR]

This study evaluates pediatric patients' radiation doses during paranasal CT procedures. A total of 48 (28 (58.3%) male, 20 (41.7%) female pediatric patients have undergone CT paranasal sinuses (PNS) in three consecutive years. The pediatric patient's radiation exposure was estimated based on justified medical procedures. Calibrated multidetector CT (MDCT) machine (Siemens Somatom Sensation 64 (64 detectors)) was used for all the procedures. All the PNS procedures were conducted at Riyadh Care Hospital. The parameters included the volume CT dose index (CTDIvol (mGy) and dose length product (DLP) (mGy.cm). The mean, standard deviation and range of the volume CTDI (mGy) and DLP (mGy.cm) for the 3 particular years were (2018) 9.36 (3.49–34.88), 196.1 (56.27–812.1), (2019) 16.9 (3.74–45.8), 333.9 (55.8–832.9) and (2020) 22.8 (4.03–45.8), 474.9 (63.9–979.02), respectively. Patients' doses were lower compared to most previous studies. However, proper exposure parameters and precise justification will reduce pediatric radiation doses during CT-PNS significantly. • Pediatric patient's radiation doses were measured during PNS CT procedures for three consecutive years. • The differences between patients to others in radiation dose is high. • CT acquisition parameter optimization is vital to reduce the dose to its minimal value. • Patients' doses were lower compared to the most previous studies. • Establishing pediatric DRL and developing a standard pediatric protocol for CT PNS are recommended. [ABSTRACT FROM AUTHOR]

Radiopharmaceuticals are utilized in diagnostic nuclear medicine (NM) for a wide range of disorders. The purposes of the work are to assess patient organ doses in bone scan procedure with 99 m Tc-Methyl diphosphonate (MDP) and quantify the NM technologist exposure during bone scan procedure. Staff radiation exposure was determined using thermo-luminescent dosimeters (TLDs, Type LiF: Mg, Cu, P (GR200A)) were placed at the dominant hand. The TLD was calibrated to estimate the personal equivalent dose Hp (10) and Hp (0.07). The mean and range of the annual personal dose equivalent (Hp (10) and Hp (0.07) mSv) were 7.6 (3.2–9.1) and 30 (17.2–44), respectively. The patients' bladder retains an insignificant amount of the administered activity. Vast differences in patients' and occupational doses were detected. Increasing staff awareness about radiation safety is recommended to enhance radiation protection and education unnecessary radiation doses. The personal doses equivalent are within the acceptable annual determined limits. • NM Technologist personal equivalent dose Hp (10) and Hp (0.07) were quantified. • Vast differences in patients' and occupational doses were detected. • The patients' bladder retains an insignificant amount of the administered activity. • The personal doses equivalent are within the acceptable annual determined limits. [ABSTRACT FROM AUTHOR]

Computed tomography (CT) frequency is approximately 11% of medical radiological procedures. Nevertheless, CT examinations contribute up to 70% collective doses. CT procedures carried out in pediatric patients represent 33% of CT procedures. This study aimed to assess pediatric doses during chest and abdomen procedures and estimated the projected radiogenic risk. In total, 83 pediatric were divided into four groups, according to their age (years). The patients were ≤six months, six months - ≤3 years, 4 - ≤ 6 years and, 7 - ≤ 15 years. The mean and range of DLP (mGy.cm) and CTDIvol (mGy) for pediatric CT chest were 42 (33–52) and 2 (1.9–2.2), respectively. The mean and range of DLP (mGy.cm) and CTDIvol (mGy) for pediatric CT abdomen pelvic region were 116 (105–129) and 3.8 (3.7–3.9), in that order. Even though pediatric' radiation doses are below the published diagnostic reference levels (DRL), additional dose reduction is required and achievable if the imaging protocol is adjusted according to the child size. • Pediatric doses during CT chest and abdomen procedures were assessed. • The variation in patients' doses was due to the scan length and child weight. • The Patients' radiation doses were lower than available published values. • The study has revealed an indispensable need for justified referring criteria. • Establishing an imaging protocol based on a pediatric subgroup is recommended. [ABSTRACT FROM AUTHOR]

This study investigates patients' dose levels during digital mammography procedures and proposes a local diagnostic reference level (DRL). The patient sample is 1055 patients who have been examined at the Riyadh Care Hospital, Riyadh, Saudi Arabia. All procedures were carried out for medically justified clinical conditions. All procedures were carried out using a direct digital mammography (DDR) radiology system. The mean and range of ESAK (mGy) were 5.19 ± 3.18 (0.33–29.9), while the mean AGD (mGy) is 1.3±(1.0–7.2) per procedure. The third quartile value for ESAK (mGy) and AGD (mGy) is 6 and 1.5, respectively. Measured ESAK (mGy) per procedure and estimated AGD are comparable with previous studies. The interpatient and interdepartmental variation is attributed mainly to the number of projections per procedure. • The average glandular dose (AGD) during mammography procedures was evaluated. • The interpatient variation is due to the number of projections per procedure. • Estimated AGD is comparable with previous studies. • Diagnostic reference should base on the patient's age and breast density. [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]

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]