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Chest computed tomography (CT) plays a vital role in the early diagnosis, treatment, and follow-up of COVID-19 pneumonia during the pandemic. However, this raises concerns about excessive exposure to ionizing radiation. This study aimed to survey radiation doses in low-dose chest CT (LDCT) and ultra-low-dose chest CT (ULD) protocols used for imaging COVID-19 pneumonia relative to standard CT (STD) protocols so that the best possible practice and dose reduction techniques could be recommended. A total of 564 articles were identified by searching major scientific databases, including ISI Web of Science, Scopus, and PubMed. After evaluating the content and applying the inclusion criteria to technical factors and radiation dose metrics relevant to the LDCT protocols used for imaging COVID-19 patients, data from ten articles were extracted and analyzed. Technique factors that affect the application of LDCT and ULD are discussed, including tube current (mA), peak tube voltage (kVp), pitch factor, and iterative reconstruction (IR) algorithms. The CTDIvol values for the STD, LDCT, and ULD chest CT protocols ranged from 2.79–13.2 mGy, 0.90–4.40 mGy, and 0.20–0.28 mGy, respectively. The effective dose (ED) values for STD, LDCT, and ULD chest CT protocols ranged from 1.66–6.60 mSv, 0.50–0.80 mGy, and 0.39–0.64 mSv, respectively. Compared with the standard (STD), LDCT reduced the dose reduction by a factor of 2–4, whereas ULD reduced the dose reduction by a factor of 8–13. These dose reductions were achieved by applying scan parameters and techniques such as iterative reconstructions, ultra-long pitches, and fast spectral shaping with a tin filter. Using LDCT, the cumulative radiation dose of serial CT examinations during the acute period of COVID-19 may have been inferior or equivalent to that of conventional CT. [ABSTRACT FROM AUTHOR]

About 70% of all collective doses from medical tests come from computed tomography (CT), the primary public radiation exposure source. Patients received higher doses during contrast-enhanced CT procedures (Angiography) than routine CT procedures. The current research aims to quantify the patients' radiation doses, estimate the cancer risk probability, and establish institutional diagnostic reference level (IDRL) during lower extremity angiography. One hundred eleven patients (61.3% male and 38.7% female) underwent contrast-enhanced CT procedures. A 160-Slice CT scanner was used for image acquisition for all patient populations. IDRL values were quantified based on the 3rd quartile value of the CT dose descriptors. All procedures were carried out at Al-Moaallim Medical City, Khartoum, Sudan. A computer software (CT-Expo, ImPACT) was used to extrapolate the effective dosage per extremity CTA examination was estimated. The mean patient age (years) was 56.1 ± 18 (18–82). The patient's radiation doses was quantified using volume CTDI and dose length product (DLP) to 7.3 ± 2 (2.9–16.8) (mGy) and 3712 ± 126 (279–8374) (mGy.cm), respectively. The average effective doses were 22 mSv (range: 1.7–50) per lower CT angiography for the lower extremity. The proposed IDRL for the VCTA procedure was 3562 mGy cm and 17 mGy for DLP and CTDIvol, respectively. The proposed IDRL is higher than the previously published studies; therefore, patient dose optimization is recommended. • Radiation doses were determined for patients undergoing VCTA procedure. • A 160-Slice CT scanner with iterative reconstruction techniques was used for examining the patients. • The average effective doses were 22 mSv (range: 1.7–50) per VCTA. • The proposed LDRL for the VCTA procedure was 3562 mGy cm and 17 mGy for DLP and CTDIvol, respectively. [ABSTRACT FROM AUTHOR]

The present study compares three different multidetector CT (MDCT) scanners for routine brain imaging in terms of image quality and radiation doses. The volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose (E) were calculated. Subjective image assessment was obtained based on a scale ranging from 1 (unacceptable) to 5 (optimum). All images scored 3.5 or over, with the 160-slice MDCT images being favoured. For the 4-, 16- and 160-slice MDCT scanners, the respective median values for CTDIvol were 57 mGy, 41 mGy, and 28 mGy; DLP values were 901 mGy.cm, 680 mGy.cm, and 551 mGy.cm; and effective doses were 2 mSv, 1.5 mSv, and 1 mSv, respectively. Compared to the 160-slice MDCT, the dose values for the 4- and 16-slice units were significantly greater. In practice, the CT modality used must be carefully selected to avoid elevated radiation doses and maintain image quality. [ABSTRACT FROM AUTHOR]

Featured Application: This study's results provide evidence for dose reductions of up to 60% in obese patients using a low-dose protocol with iterative reconstruction, whereby the benefits greatly outweigh the radiogenic risks from computed tomography (CT) procedures. The aim of this study was to evaluate the implications of low radiation dose in abdominal computed tomography (CT) when combined with noise reduction filters and to see if this approach can overcome the challenges that arise while scanning obese patients. Anthropomorphic phantoms layered with and without 3-cm-thick circumferential animal fat packs to simulate different sized patients were scanned using a 128-slice multidetector CT (MDCT) scanner. Abdominal protocols (n = 12) were applied using various tube currents (150, 200, 250, and 300 mA) and tube voltages (100, 120, and 140 kVp). MOSFET dosimeters measured the internal organ dose. All images were reconstructed with filtered back projection (FBP) and different iterative reconstruction (IR) strengths (SAFIRE 3, SAFIRE 4, and SAFIRE 5) techniques and objective noise was measured within three regions of interests (ROIs) at the level of L4–L5. Organ doses varied from 0.34–56.2 mGy; the colon received the highest doses for both phantom sizes. Compared to the normal-weighted phantom, the obese phantom was associated with an approximately 20% decrease in effective dose. The 100 kVp procedure resulted in a 40% lower effective dose (p < 0.05) compared to at 120 kVp and the associated noise increase was improved by increasing the IR (5) use, which resulted in a 60% noise reduction compared to when using FBP (p < 0.05). When combined with iterative reconstruction, the low-kVp approach is feasible for obese patients in order to optimize radiation dose and maintain objective image quality. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to first measure patient doses during computed tomography (CT) chest, abdomen, and extremities procedures for evaluation lymphedema, and second to estimate the radiation dose-related risks during the procedures. Material and Methods: Radiation effective doses from CT lymphography procedures quantified using CT machines from different vendors. After the calibration of CT systems, the data collected for a total of 28 CT lymphography procedures. Effective and organ doses extrapolated using national radiological protection software based on Monte Carlo simulation. Results: The mean patient doses for chest and abdomen procedures in term of CTDIvol (mGy) and DLP (mGy.cm) are 10.0 ± 3 and 425 ± 222 and 24 ± 12 and 1118 ± 812 for CT 128 and CT 16 slice, respectively. The mean DLP (mGy.cm) for extremities was 320 ± 140 and 424 ± 212 for CT 128 and CT 16 slice, in that order. Conclusion: Patients' dose showed significant differences due to variation in the scan length and clinical indication. Organs lay in the primary beam received high radiation doses especially in the chest region which increases the probability of radiation-induced cancer. The current patient's doses are higher compared to the previous studies. [ABSTRACT FROM AUTHOR]

Due to the extended localized fluoroscopy, many radiographic exposures, and multiple procedures that might result in tissue reaction, patients and personnel received a significant radiation dose during interventional cardiology (IR) procedures. This study aims to calculate the radiation risk and assess patient and staff effective doses during IC procedures. Thirty-two patients underwent a Cath lab treatment in total. Ten Cath lab personnel, including six nurses, two cardiologists, and two X-ray technologists. Optical stimulating-luminescent dosimeters (OSL) (Al2O3:C) calibrated for this purpose were used to monitor both occupational and ambient doses. Using an automated OSL reader, these badges were scanned. The Air Kerma (mGy) and Kerma Area Products (KAP, mGy.cm2) have a mean and standard deviation (SD) of 371 ± 132 and 26052, respectively. The average personal dose equivalent (mSv) and its range for cardiologists, nurses and X ray technologists were 1.11 ± 0.21 (0.96–1.26), 0.84 ± 0.11 (0.68–1.16), and 0.68 ± 0.014 (0.12–0.13), respectively. The current study findings showed that the annual effective dose for cardiologists, nurses, and X-ray technologists was lesser than the yearly occupational dose limit of 20 mSv recommended by national and international guidelines. The patients' doses are comparable with some previously published studies and below the tissue reaction limits. • Occupational and patient-effective doses were quantified during Cath lab procedures. • The staff dose was measured using calibrated optical stimulating-luminescent dosimeters (OSL) (Al2O3:C). • The annual effective dose for Cath lab personnel is within the defined dose limit. • The Cath lab personnel was well protected according to the current workload. [ABSTRACT FROM AUTHOR]

Background: Radiation exposure due to computed tomography (CT) has become an important issue, as the number of CT examinations has been increasing worldwide. Radiation doses associated with CT are higher in comparison to other imaging procedures. CT-related radiation doses should be monitored and controlled in order to ensure reduction of radiation exposure and optimization of image quality. The aim of this study was to evaluate radiation doses in adult patient who underwent routine CT brain examinations, and to assess how CT scanning protocols affect patient doses in practice. Material/Methods: A total of 118 patients underwent brain CT at two radiology departments equipped with 64-slice CT scanners, Khartoum, Sudan. Patient doses regarding weighted CT dose index (CTDIw) and dose length product (DLP) values were recorded. Quality control tests were performed for both scanners. Results: The mean CTDIw values ranged from 62.9 to 65.8 mGy, DLP values ranged from 1003.7 to 1192.5 mGy, and the effective dose varied from 2.4 to 3.7 mSv. Conclusions: Patient doses in this study was higher compared to previous research, suggesting that patients exposed to unnecessary radiation. Therefore, optimization of radiation doses with the use of specified imaging protocols, well-documented indications for CT, training of technicians, and quality control programs will reduce the necessary radiation doses. Establishment of the diagnostic reference level is recommended for further dose reduction. [ABSTRACT FROM AUTHOR]

Computed tomography (CT) procedures are the largest source of medical radiation exposure in children and adults. Numerous children undergo high-radiation-dose examinations due to the increasing utilization of CT in children and the wide range of radiation doses. It is therefore necessary to protect pediatric patients, because of their higher sensitivity to ionizing radiation. This study aimed to establish a multicenter cohort of pediatric patients who received CT scans and predict the radiation-related cancer risk. Ninety-five patients who underwent various CT scans [brain 64 (67.4%), chest 14 (14.7%), abdomen 17 (17.9%)] were referred to one of three hospitals. All patients were examined using one of three identical multi-detector CT machines (Toshiba Aquilion 64) according to standard departmental imaging protocols. The average effective doses per scan for brain, chest, and abdominal procedures were 49.7, 34, and 40 mSv, respectively. Dose-reduction measures might significantly decrease the number of radiation-induced malignancies in children. • Radiation dose was quantified for CT brain, chest, and abdomen procedures. • Three 64 multi-detector CT machines from a single vendor were used. • The radiogenic risks per procedure are 6.5, 4.4, and 5.2 per 10-3 CT brain, chest, and abdomen, respectively. • Children received high-dose per exam and higher than previously reported. [ABSTRACT FROM AUTHOR]

This study intended to optimize the radiation doses for gastroenterologists and patients during therapeutic endoscopic retrograde cholangiopancreatography (ERCP) and to compare the doses based on available data obtained by other researchers. A total of 153 patients were studied in two Gastroenterology Departments, (group A, 111; group B, 42). Thermoluminescent dosimeters (TLD) were used to measure the staff and patients entrance surface air kerma (ESAK) at different body sites. The mean ESAK and effective doses per procedure were estimated to be 68.75mGy and 2.74mSv, respectively. Staff was exposed to a heterogonous doses. The third examiner (trainee) was exposed to a high dose compared with other examiners because no shield was located to protect him from stray radiation. Patients and examiners doses were lower compared to the lowest values found in previous studies taking into consideration the heterogeneity of patients and equipment. Staff doses during ERCP are within the safety limit in the light of the current practice. [ABSTRACT FROM AUTHOR]

The objective of this study is to assess the patients' effective and organ dose during theranostic applications in Kuwait. In total, eighteen adults' patients were conducted nuclear medicine procedures with 177Lu Dotatate for theranostic purpose in Kuwait Cancer control center (KCCC), Kuwait. Medium energy collimator (MEC) (208 keV Scatter 26% better than 113 keV Scatter 60%) was utilized to obtain scans in definite time intervals ranged from one to 2 h (before voiding), 6:00, 24:00, 48:00, 72:00 h. Patients, tissue and organ radiation doses were computed utilizing OLINDA/EXM Software. The average radiation effective dose (in mSv/MBq) for bladder, liver, and both kidneys (left & right), were 0.36, 0.08, 0.61 & 0.60. The range of the effective dose was from 0.55 mSv to 7.7 mSv. The acquired scans using 177Lu were delivered diagnostic findings. The patients' effective dose is lower compared to the previous studies. Variation is attributed to the departmental protocol and administered activity. The values of the mean organ dose were comparable and lower than previously published studies. Different organs have different level of doses, which may affected by the presence of the metastatic tumors in the entire organ. • Patients' organs dosimetry in targeted radionuclide therapy were carried out in Kuwait Cancer Control Centre. • A total of 18 patients were undergone theranostic procedures with 177Lu Dotatate. • Organ and total patients doses were calculated using Organ Level INternal Dose Assessment (OLINDA) Software. • Optimization of the PET/CT imaging protocol is recommended to assure that patients received a minimal effective dose. [ABSTRACT FROM AUTHOR]

The purposes of this study are to estimate patient's radiation doses and radiogenic risk in vascular lower limb computed tomography (CT). In total, 188 (109 (68%) males and 79 (42%) females) patients undergone vascular CT for the lower limbs at three radiology departments. Three CT scanners, 160, 128, and 64 slices CT, were used in this study. CT-Expo and ImPACT CT dose estimation software were used to extrapolate the effective dose. The overall average and range of volume CT dose index (CTDIvol (mGy) and dose length product (DLP) (mGy.cm) 7.3 (2.3–22.9), and 3000 (279.1–8374.4) the same order. The overall effective dose average value was 18 mSv per procedure. The proposed diagnostic reference level (DRL) values are 9 mGy (CTDIvol) and 2500 mGy cm (DLP) per vascular lower limb CT procedure. The risk of cancer from the peripheral CT angiography procedures ranges from 1 in 1000 to 1 in 3000 procedures. The cancer risk per procedure should be considered during the justification and image acquisition stages. • Peripheral CT angiography for lower extremities were performed using three CT machines. • CT dose per procedure (DLP (mGy.cm) is higher up to 10 times compared to previous. • Patients are being seen to be receiving unnecessary radiation doses during triphasic CT abdomen procedure. • A local diagnostic reference level was proposed was established for further dose reduction. [ABSTRACT FROM AUTHOR]

This study aimed to measure entrance surface air kerma (ESAK, in mGy) during routine skull X-ray examinations of adult patients and to establish a local diagnostic reference level (LDRL) in the diagnostic radiology department of King Khalid Hospital in Majmaah. The patient's ESAK, mGy and effective dose (ED, in mSv) at the 75th percentile were calculated based on the output of the X-ray tube and the exposure parameters, as well as the use of suitable conversion coefficients, respectively. To calculate the ED and patient's ESAK, the output and exposure characteristics of the X-ray tube and relevant conversion coefficients were considered (ESAK). Additionally, the 75th percentile distributions for the ESAK and KAP distributions were calculated. A wide range of ESAK was observed, which might be due to the difference in the exposure factors applied for each examination. The mean values of ESAK and KAP together with 75th percentiles for Anteroposterior (AP) and lateral skull projection were 0.22 (0.10–0.30) mGy, 0.24 (0.0.18–0.25) mGy and 0.21 (0.19–0.26) Gy.cm2, 0.29 (0.17–0.32) Gy.cm2, respectively. The findings were significantly lower than national reference levels, the most reported European DRL values, and other previously reported dose values. The measured ESAK and KAP were within the recommended and acceptable dose limits. The best radiation protection can be achieved by optimizing the radiation dose while preserving image quality. • The patient's ESAK effective dose were calculated based on the exposure parameters. • Radiation application has increased as a result of technological progress. • The best radiation protection can be achieved by optimizing the radiation dose. [ABSTRACT FROM AUTHOR]

Due to variation among radiographers' practice, and the importance of unifying practice during radiography for optimizing radiation level and image quality, the current manuscript aims to assess the radiation dose level and propose local diagnostic reference levels (LDRL) for posterior-anterior (PA) chest, antero-posterior (AP) abdomen, and pelvis examinations in two hospitals in Khartoum ('K') and one hospital in Wad-Medani ('M') cities, Sudan. Along with patient demographics like height and weight, the radiation exposure parameters including tube potential, current, and radiation duration were documented. This included 732 patients whose tests were conducted at one of three departments located in two different cities. The entrane surface air kerma (ESAK) was calculated using DosCal software and an Unfors -Xi-meter. The average ESAK for an X-ray of the chest was 0.18 mGy in M, 0.19 mGy in K (averaged over two hospitals in the K), for the abdomen it was 1.1 and 1.23 mGy, and for the pelvis it was 1.8 and 01.9 mGy respectively. The proposed DRL was achieved from the third quartile of radiation dosage of data, and it was 0.21, 1.7 and 1.9 mGy for the chest, abdomen and pelvis respectively. There was a wide variation in dosage levels among the three hospitals. The current proposed DRL was lower than most literature for the chest, abdomen and pelvis. More studies are recommended for other examinations such as skull and contrast media studies. • Radiation dose level for chest, abdomen and pelvis was assessed in major hospitals in Sudan. • Average dose for conventional X-ray of chest, abdomen and pelvis was 0.19, 1.2 and 1.9 mGy respectively. • Local diagnostic reference level was suggested for the above examinations. • The Suggested LDRL was lower than available literature. [ABSTRACT FROM AUTHOR]

Cardiovascular nuclear medicine (NM) imaging examinations expose patients to extremely high absorbed doses of ionizing radiation, which necessitates extensive efforts to reduce the doses without compromising the quality of images. This study aims to assess patients' radiation doses to patients and public exposure in Cardiac rest and stress single photon emission computed tomography (SPECT) scans. The patients' exposure was calculated for 21 patients using the administered activity (AA, MBq). (GE SPECT) was the device used for all patients. AA (MBq) mean and range were 370 for Rest and 1110 for Stress. The average range of the dose rate was 1.59 (0.67–2.34) mR/h for rest and 7.29 (4.2–9.98) mR/h for stress when computed at 30 cm from the patient's chest level after injection. At 100 cm from the patient, the mean dose rate values were 0.37 (0.16–0.73) mR/h for rest and 1.39 (1.01–2.0) mR/h for stress. The overall effective dose is 12.1 mSv per rest and stress SPECT procedure. The mean effective dose for cardiac rest is comparable with previously published studies while the effective dose from cardiac stress is higher than previously published studies. The variation in the effective dose depends on several factors, including the department's clinical indication imaging protocols and radiation safety measures. • The patient's effective dose and dose were quantified during cardiac rest and stress SPECT procedures. • The mean effective dose for cardiac rest is comparable with previously published studies. • The effective dose from cardiac stress is higher than previously published studies. • The current AA activity for rest and stress is lower than the DRL and the previous studies. [ABSTRACT FROM AUTHOR]

Renal diseases and urinary tract disorders are causing a global burden, with an estimated prevalence of around 13%. Contrast-enhanced computed tomography urography (CE-CTU) is a well-known diagnostic technique for urinary system diseases for initial diagnosis and, very often, for follow-up. CE-CTU procedure exposes patients to high doses of ionizing radiation; hence, justification and optimization of doses are necessary to maximize the benefits and minimize the patients' risks. This study aims to evaluate radiation doses to patients during CE-CTU procedures and estimate the subsequent radiogenic risk. The study included twenty-seven patients who underwent CE-CTU examination in two different hospitals (National Ribat Hospital (NRH) and National Security Fource Hospital (NSFH)), where 16-slice CT machines from different vendors are used. The variables and significance were analyzed using SPSS and Scheffe's statistical tool. Data collected included the age of patients (19–70 years), the radiation dose received by patients: dose length product (DLP, mGy.cm) and volume CT dose index (CTDIvol (mGy)), and tube current-time product (mAs). Patients' dose measurements per CE-CTU procedure given as (mean and range) was: DLP 3098 (647–5301) (mGy.cm) and CTDIvol 44.11 (15–136) (mGy). The results revealed statistically significant differences in DLP (mGy.cm), CTDIvol (mGy), and mAs, and this could be attributed to discrepancies in protocols, machines, and operators among the hospitals and within each hospital. Considering gender, the variables (age, tube current-time product (mAs), and CTDIvol) showed no statistically significant differences. The radiogenic risks from the CE-CTU procedure were ≈1 per 400. Comparison between the two hospitals showed that the variables varied significantly between the hospitals studied, but no significant differences were found based on gender. CE-CTU with contrast medium exposes patients to high doses. Therefore, proper dose optimization is crucial. • The radiation doses during IVU and the subsequent risks from exposure are studied. • The entrance-surface air kerma (ESAK) and effective dose were quantified. • Calculation of the overall cancer risk yielded 5.85 per million procedures. • The effective and cancer risk are around ten times lower during IVU procedures compared to CTU. [ABSTRACT FROM AUTHOR]

Mammary glands or breasts are radiosensitive organs that makeup 12% of the body's overall radiation sensitivity. According to estimates, Saudi Arabia has a 27.3% overall cancer incidence rate for breast cancer. Recent studies reported that breasts get significant organ equivalent doses during diagnostic procedures with ionizing radiation, even though the breast is not the target organ. The objective of this work is to assess the effective and breast equivalent doses during positron emission tomography (PET)/Computed tomography (CT) imaging examinations. The effective and breast equivalent doses per PET/CT (GE PET/CT 710) examination were quantified using the amount of the injected radiopharmaceutical (MBq) (18F- fluorodeoxyglucose (FDG)), and external doses from CT examinations. The average, standard deviation (SD) and range of examined patients' age (years) and body mass index ((BMI), kg/m2) were 58 ± 11 (39–76) and 30 ± 5 (20.7–43.1), respectively. Constant administered activity (AA, 185 MBq) and tube potential (120 kVp) were used for all patients. The average, SD, and range of the patients effective dose (mSv) from PET/CT (18F- FDG) examination was 8.0 ± 0.93 (7.0–10.0) and 2.075 ± 0.11 (1.91–2.29) in that order. Breast doses are comparable with previous studies during the PET/CT and mammographic examination. Proper justification criteria and dose optimization are essential to lowering excessive exposure while preserving image quality, especially for young females because they have a higher risk of radiation-induced cancer. • Breast doses during PET/CT imaging procedures were evaluated. • Breast absorbed dose depends on CT protocol and administered activity. • The organ equivalent dose ranged from 1.91 to 2.29 mGy per procedure. • Breast doses are comparable with previous studies PET/CT procedures. • Young females have a higher risk of breast cancer due to PET/CT procedure. [ABSTRACT FROM AUTHOR]

Medical personnel working with ionizing radiation are exposed to significant radiation doses. Previously published studies reported increased incidence of induced cancer and cataracts among radiation workers in medical and industrial premises due to exposure to ionizing radiation. Therefore, an assessment of occupational exposure is recommended. The purpose of this study is to estimate the radiation risk caused by staff exposure and ambient exposures during diagnostic radiography. The study involved 46 staff members: 38 technologists, 8 Radiologists and 22 patients: 11 undergoing conventional radiology and 11 undergoing fluoroscopic radiology. Occupational and ambient doses were measured using calibrated optical stimulating-luminescent dosimeters (OSL) (Al2O3:C). These badges were read using an automatic OSL reader. Patients' doses were calculated form the reading of the x-ray machines. Calculating the dose parameters for patients, the mean and standard deviation (SD) of the kVp, mAs, and patient doses in terms of Dose Area Product (DAP)were 113.1 ± 16.2, 7.5 ± 11.65, and 869.6, respectively. The mean and range of the annual effective dose (mSv) for technologists was (0.6 ± 0.36) (0–2.11). The mean and range of effective dose (mSv) for Radiologists were (0.48 ± 0.19) (0.17–0.74). The occupational exposure in this study showed that radiology technologists and radiologists are exposed to a low dose according to the current workload. The staff dose reported in this study is lower than those available in most previous studies. • Staff annual radiation dose were assessed for radiology technologists for two consecutive years. • Occupational doses were quantified with OSL dosimeters. • The occupational exposure is 90% below the annual dose limits. [ABSTRACT FROM AUTHOR]

The pathology of the urinary system is usually investigated using Intravenous Urography (IVU). The study objectives are to quantify patients' radiation dose and radiation induced malignant tumors risk during IVU examination. The radiation doses during IVU and the subsequent risks from exposure are studied, using data from 50 patients imaged in one hospital. The demographic data given as (mean ± std) was as follows:The age of patients was 39 ± 14 years; height of patients was 1.7 ± 0.1 m, the mass was 69 ± 10 kg and the body-mass-index was 24.3 ± 4.1 kg m−2. The physical exposure parameters recorded were: kVp: 74.04 ± 3.1, mAs: 33.64 ± 4. Moreover, the average number of films per procedure was 5.72 ± 1.49. The entrance-surface air kerma (ESAK) was 2.1 ± 0.64 mGy, and the mean effective dose was 0.131 ± 0.04 mSv. Calculation of the overall cancer risk yielded 5.9 × 10−6 procedures. ESAK (mGy) and effective dose values obtained in this study were comparable with reported studies as shown in the text. The effective and cancer risk are around ten times lower during IVU procedures than for example, contrast enhanced computed tomography urography (CTU) examination. Reduction of doses received by patients to meet the values of the diagnostic reference levels without compromising the quality and clarity of the images is highly recommended. Radiation dosimetry; IVU; Radiology; Cancer risk; medical imaging. • The radiation doses during IVU and the subsequent risks from exposure are studied. • The entrance-surface air kerma (ESAK) and effective dose were quantified. • Calculation of the overall cancer risk yielded 5.85 per million procedures. • Patients received higher doses due to unoptimized imaging protocol. [ABSTRACT FROM AUTHOR]

A significant source of ionizing radiation for medical use is computed tomography (CT). According to estimates, more than 84 million CT scans are carried out yearly in the US. Because the neck area contains several organs and tissues that are very sensitive to ionizing radiation, such as the thyroid gland, CT for the neck region is commonly done for a variety of clinical causes. This study's goal is to assess the patient doses to radiosensitive organs and effective doses received during the CT neck surgery in the pastAt Riyadh Care Hospital, a multislice CT (MSCT) system (Siemens Somatom Sensation, 64 slices/detector) was used to perform improved CT treatments on a total of 54 patients. Patient ages were 41.5–15.5 years old on average, with a wide variation (21–73). Using computer software based on Monte Carlo simulation, organ and effective dosages were assessed. The International Commission of Radiological Protection (ICRP) risk variables were used to calculate the patient's radiogenic risk for a particular organ. The patients' dose length product (DLP, mGy.cm) for CT neck examination were 993.3 ± 539.5 (267.3–2441.7). The mean and range of volume CT dose per slice (CTDIvol (mGy)) were 1.5 ± 3.9 (3.91–22.55). The overall effective dose (mSv) per procedure is ranged from 1.3 to 11.7 with a mean value 2.8 mSv. Patients' CT neck procedures have been repeated the procedure up to 7 times during the treatment course. The risk of malignancy is 1x10-6 CT procedure. The study showed that patients received wide discrepancies in patients' doses up to 9 times. Optimization of image acquisition protocol and scan length is necessary to reduce the unnecessary risk. • The effective and organ equivalent doses during neck CT procedure were studied. • Lens of the eye, salivary gland and thyroid gland received a high radiation dose. • The overall effective dose (mSv) per procedure is ranged from 1.3 to 11.7 • Patients' CT neck procedures have been repeated the procedure up to 7 times during the treatment course. [ABSTRACT FROM AUTHOR]

Image-guided radiation therapy (IGRT) adds an additional imaging radiation dose to existing levels of therapeutic radiation. The extra radiation dose received by organs from multiple conae beam computed tomography (CBCT) scans can increase the probability of the secondary cancer risk. In this study, an effort has been made to assess CBCT dose and image quality for standard pre-sets defined for different organs namely, the chest, pelvis, brain, head and neck, and abdomen. The second goal was to investigate whether the radiation dose could be reduced while still achieving high image quality. Image quality was evaluated on the CatPhan Model 503 (Phantom Lab, NY), while organ kV- CBCT doses were evaluated using an Unfors device (Fluke Biomedical) to provide representative measurements for clinical settings. Nominal CBCT projections with reduced exposure times were reconstructed in 3D using the Unfiltered and Filtered-back Projection algorithms. Patient organ dose (mGy) per procedure for brain, chest, pelvis, abdomen, and head and neck were 7.9, 35.3, 28.1, 58.3, and 0.77, respectively. The experimental analysis suggests that adequate image quality could be obtained while decreasing the number of radiographic projections. Reducing the number of the radiographic projections will reduce the scan time and therefore the imaging dose. The proposed method provides an opportunity to reduce the organ doses comparatively lower than the standard CT doses for head and body protocols. The study provides a framework for delivering low radiation doses to critical organs with no risk of long-term exposure. • This study has successfully quantified CBCT doses for some critical organs. • Image quality and radiation dose were evaluated during CBCT. • Adequate image quality could be obtained while decreasing the number of radiographic projections. • The study provides a framework for delivering low radiation doses to critical organs with no risk of long-term exposure. [ABSTRACT FROM AUTHOR]

Ionizing radiation exposure from medical applications is increasing annually worldwide. It was estimated that 325 million dental procedures were performed in the United States. Radiation exposure from dental radiography consists of intraoral, panoramic, and 3D imaging cone-beam computed tomography (CBCT) imaging. Recent studies reported an association between dental imaging procedures and increased cancer probability of brain and thyroid. Previous studies showed that some dental imaging practices exposed patients and staff to unnecessary radiation doses due to incorrect image acquisition and insufficient radiation protection measures. This study aims to (i) measure the occupational and patients doses during dental procedures and (ii) assess the current imaging techniques and radiation protection practices. Two hundred fourteen patients were evaluated for periapical, bitewing, cephalometric, occlusal, and panoramic procedures. Organ equivalent doses were quantified for the breast, eye lens, and thyroid gland during CBCT procedure. Occupational and ambient dose assessment were assessed using calibrated thermoluminescent dosimeters (TLD-100(LiF: Mg. Ti). Ambient doses were measure at different locations at the department using TLDs. Patients' radiation doses were quantified using kerma area product (PKA (mGy.cm) and the entrance surface air kerma (ESAK (mGy). Fixed tube voltage (65 kVp) and tube current-time product (7 mAs) were used. The overall mean, sd, and range of patients dose values during intraoral (mGy), panoramic and CBCT examinations were 4.6 ± 0.7 (1.4–7.1), 135 ± 45 (75.2–168.5), and 215 ± 165 (186–2115), respectively. The mean and range of the annual occupational doses (mSv) were 1.4 (0.6–3.7), which below the annual dose limits for radiation workers (20 mSv/y). The study showed that inadequate radiation protection for patients existed in terms of the use of the thyroid shield, the technologist's presence inside the room during radiation exposure. Patients' radiation doses were comparable with the international diagnostic reference level (DRL). Staff education and training in radiation protection aspects are highly recommended. • Radiation doses from intraoral, panoramic, and 3D imaging cone-beam computed tomography imaging were quantified. • Ambient and occupational doses were measure at different locations at the department using TLD. • The study showed that inadequate radiation protection for patients existed in terms of the use of the thyroid shield. • CBCT dose values, the patient radiation dose is around two times higher than for a panoramic imaging procedure. • The mean and range of the annual occupational doses (mSv) were below the annual dose limits for radiation workers. [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]

This study aimed to assess the main factors affecting radiographic image quality in selected routine radiography procedures, to establish guidelines for maintaining the expected quality, while keeping the patient radiation doses as low as possible. Entrance surface air kerma (ESAK) for 811 patients undergoing chest, abdomen and pelvis x-ray procedures in ten X-ray departments were assessed using the European Image Criteria method. Basic quality control (QC) tests were performed to check the compliance of x-ray machines with the international standards. The mean percentage and range of good quality images were 71.3 (56–86.1) for chest posterior anterior (PA), 76.1 (65–91) for abdomen anterior posterior (AP) and 70.7 (35.7–92.6) for pelvis anteroposterior (AP). The corresponding ESAK (mGy) were 0.5 ± 0.3, 3.7 ± 1.7 and 3.6 ± 1.6 per procedure, respectively. These image quality findings reveal wide inter and intra-hospital variations. The ESAK values for patients undergoing abdominal and pelvic X-ray procedures showed comparable values in relation to the international diagnostic reference levels (DRLs), while they were twice as high for chest X-ray procedures. Improper image processing, exposure factor errors, and suboptimal patient communication and instructions prior to examination were the main factors commonly responsible for inadequate quality radiographs. The radiation dose variations are according to variable patient demographic data across the hospitals and type of examination, besides the variations of the applied technical parameters for each given examination. The film reject rates are higher in most hospital compared to the World Health Organization (WHO) recommended value. Establishment of image quality criteria will improve the department productivity and will reduce the reject rate. • Factors affecting radiographic image quality and radiation dose were analyzed. • Entrance surface air kerma were assessed for chest, abdomen and pelvis procedures. • Image quality were assessed according to the European Commission Criteria. • Entrance surface air kerma were higher compared to previous studies. [ABSTRACT FROM AUTHOR]