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Acceptance testing and commission are essential elements of the quality assurance program for imaging equipment. We present the results of a performance evaluation of Flat Panel-Based Cardiovascular Fluoroscopy X-ray Systems as a part of acceptance testing and commissioning. Measurements were obtained using a calibrated dose rate meter, patient equivalent phantoms, and Leeds image quality test tools. The results were compared with the manufacturer and European acceptability criteria. The entrance surface air kerma (ESAK) rate ranged from 8.0 to 12.0 mGy min−1 in the continuous mode and from 0.01 to 0.04 mGy fr−1 in the pulsed mode of operation. Detector-input air kerma rates ranged from 0.29 to 0.39 mGy min−1 in continuous mode and from 0.02 to 0.07 µGy fr−1 in pulsed mode. Fluoroscopy device half-value layer (HVL) ranged from 2.5 to 3.0 mm Al, and the low resolution ranged from 0.9 to 1.3%. The spatial resolution limit was double that of the image intensifier (2.4 to 3.6) lp/mm. Flat-panel fluoroscopy demonstrated superior image quality and dose performance as compared to conventional image intensifier-based fluoroscopy. The quality assurance measurements presented are essential in the rapid evaluation of the imaging system for acceptance testing and commissioning. [ABSTRACT FROM AUTHOR]

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

The present study aims to assess Abu Rusheid and Um Naggat albite granite's natural radioactivity in the Central Eastern Desert, Egypt, using an HPGe laboratory spectrometer. A total of 17 albite granite samples were detected for this study. The activity concentrations were estimated for 238U (range from 204 to 1127 Bq/kg), 226Ra (range from 215 to 1300 Bq/kg), 232Th (from 130 to 1424 Bq/kg) and 40K (from 1108 to 2167 Bq/kg) for Abu Rusheid area. Furthermore 238U (range from 80 to 800 Bq/kg), 226Ra (range from 118 to 1017 Bq/kg), 232Th (from 58 to 674 Bq/kg) and 40K (from 567 to 2329 Bq/kg) for the Um Naggat area. The absorbed dose rates in the outdoor air were measured with average values of 740 nGy/h for Abu Rusheid albite granite and 429 nGy/h for Um Naggat albite granite. The activity concentration and gamma-ray exposure dose rates of the radioactive elements 238U, 226Ra, 232Th and 40K at Abu Rusheid and Um Naggat exceeded the worldwide average values that recommend the necessity of radiation protection regulation. Moreover, the corresponding outdoor annual effective dose (AEDout) was calculated to be 0.9 and 0.5 mSv y−1 for Abu Rusheid and Um Naggat albite granite, respectively, which are lower than the permissible level (1 mSv y−1). By contrast, the indoor annual effective dose (AEDin) exceeded the recommended limit (3.6 and 2.1 for Abu Rusheid and Um Naggat, respectively). Therefore, the two areas are slightly saving for development projects concerning the use of the studied rocks. The statistical analysis displays that the effects of the radiological hazard are associated with the uranium and thorium activity concentrations in Abu Rusheid and Um Naggat albite granites. [ABSTRACT FROM AUTHOR]

One the most complicated gastrointestinal procedures, endoscopic retrograde cholangio-pancreatography (ERCP) uses fluoroscopy guidance of an endoscope to diagnose and treat hepatobiliary system pathologies. As is true of all approved interventional radiology, it is justified by the massive benefit that it is capable of delivering, one which for the patient far outweighs the risks from radiation exposure. Nevertheless, for both patients and staff there is a need to minimize the risk of carcinogenesis and the potential for tissue reactions. Recent concern has been shown in regard to radiation induced eye lens opacifications and cataract, most particularly for the members of staff who during their regular theatre practice are in closest contact with the patient. Therefore, optimum balance between benefit versus radiation risk is required. This study reviews patient and staff dose during ERCP procedures, also seeking to provide comprehensive data regarding radiation exposure management techniques. Patient and staff doses depend on the operators, equipment and patient related factors, benefitting from awareness and experience in respect of radiation protection techniques and the availability of modern fluoroscopic equipment. It is apparent that in high workload departments, staff doses to eye lens may exceed the limits on annual exposure. • Previous studies in patients and occupational dosimetry had been studies. • Patients and staff remain constant regardless of the X ray technology development. • ERCP is safe during pregnancy for patients and pregnant workers. • It is apparent that in high workload departments, staff doses to eye lens may exceed the limits on annual exposure. • Lack of training and monitoring services in gastroenterology department are frequently reported. [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]

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]

Exposure to ionizing radiation may induce cancer risk to the patients proportional to the radiation absorbed dose and the organ sensitivity. Therefore protection of radiation exposure is essential to minimize the radiation cancer risk and prevent the deterministic effects. The International Atomic Energy Agency (IAEA) encourages member countries to establish national diagnostic reference levels (DRLs) to reduce unjustified radiation exposure. This study establishes a local DRL for computed tomography (CT) abdomen and pelvis procedures. In total, 1444 CT abdomen procedures were carried out during nine months. CT abdomen procedures were carried out at King Faisal Specialist Hospital and research center using six CT machines from different vendors. The mean and range of patients' weight (kg) are 50 (42–120). The recommended DRLs values in DLP (mGy.cm) and CTDIvol (mGy) were 900 and 15 per CT abdomen and pelvis procedure, respectively. 3% (41 cases) were higher than the national DRL for CT abdomen and pelvis. The proposed DRL values are slightly higher than the European and the American College of Radiologists (ACR) DRL values in DLP. The purpose of DRL in terms of CTDIvol (mGy) is comparable with the international guidelines. Thus reducing the scan length, is recommended ensuring that patients receive a minimal possible radiation dose while maintaining the image quality. • Patient radiation was calculated for CT abdomen examinations. • Six multi-detector CT machines 64, 128, 384 and 256 (three machines) were used. • 3% (41 cases) were higher than the national DRL for CT abdomen and pelvis. • The proposed DRL is higher than previously reported values in Europe. [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]