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Evaluation occupationally radiation exposure during diagnostic imaging examinations

Johary YH, Albarakati S, AlSohaim A, Aamry A, Aamri H, Tamam N, et al.

Appl Radiat Isot, 2023 Mar;193:110648.
PMID: 36669265 DOI: 10.1016/j.apradiso.2023.110648

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

Matched MeSH terms: Radiation Exposure*
SCATTER RADIATION IN THE FLUOROSCOPY-GUIDED INTERVENTIONAL ROOM

Bohari A, Hashim S, Mohd Mustafa SN

Radiat Prot Dosimetry, 2020 Jun 24;188(3):397-402.
PMID: 31950168 DOI: 10.1093/rpd/ncz299

Radiation scattered throughout the room during fluoroscopy-guided interventional (FGI) procedures was quantified at different locations using nanoDot optically stimulated luminescence dosemeters. All the tube angulation imaging shows that the radiation spectrum resembled a single peak distribution. The left anterior oblique 90° shows the highest single peak distribution (28.65 mSv/h). The single peak distribution for standard anteroposterior, left anterior oblique 45° and right anterior oblique 45° imaging was 13.32, 22.99 and 17.40 mSv/h, respectively. All tube angulation shows that the position of the interventional radiologist experienced a higher radiation level compared to other staffs. The doses of radiation varied widely around the perimeter of the patient's table and changed in accordance to imaging angles during procedures. Knowledge pertaining to radiation exposure levels is integral in order to avoid adverse risks, particularly among staff.

Matched MeSH terms: Radiation Exposure*
Fulltext Structural and optical properties of lead-boro-tellurrite glasses induced by gamma-ray

Mustafa IS, Kamari HM, Yusoff WM, Aziz SA, Rahman AA

Int J Mol Sci, 2013;14(2):3201-14.
PMID: 23380963 DOI: 10.3390/ijms14023201

Spectrophotometric studies of lead borotellurite glasses were carried out before and after gamma irradiation exposure. The increasing peak on the TeO(4) bi-pyramidal arrangement and TeO(3+1) (or distorted TeO(4)) is due to augmentation of irradiation dose which is attributed to an increase in degree of disorder of the amorphous phase. The structures of lead tellurate contain Pb(3)TeO(6) consisting of TeO(3) trigonal pyramid connected by PbO(4) tetragonal forming a three-dimensional network. The decrease of glass rigidity is due to irradiation process which is supported by the XRD diffractograms results. The decreasing values of absorption edge indicate that red shift effect occur after irradiation processes. A shift in the optical absorption edge attributed to an increase of the conjugation length. The values of optical band gap, E(opt) were calculated and found to be dependent on the glass composition and radiation exposure. Generally, an increase and decrease in Urbach's energy can be considered as being due to an increase in defects within glass network.

Matched MeSH terms: Radiation Exposure
Fulltext Radiotracer injector: an industrial application (RIIA)

Noraishah, O., Mohd Arif, H., Fadil Ismail, Nurliyana Abdullah, Mior Ahmad Khusaini, Mohamad Rabaie, S., et al.

Journal of Nuclear and Related Technologies, 2011;2011(2):100-104.
MyJurnal

The radiotracer injector is meant for transferring liquid radiotracer in the system for industrial radiotracer application with minimal radiation exposure to the operator. The motivation of its invention is coming from the experience of the workers who are very concern about the radiation safety while handling with the radioactive source. The idea ensuring the operation while handling the radioactive source is fast and safe without interrupting the efficiency and efficacy of the process. Thus, semi automated device assisting with pneumatic technology is applied for its invention.

Matched MeSH terms: Radiation Exposure
Health and ecological hazards due to natural radioactivity in soil from mining areas of Nasarawa State, Nigeria

Aliyu AS, Ibrahim U, Akpa CT, Garba NN, Ramli AT

Isotopes Environ Health Stud, 2015;51(3):448-68.
PMID: 25848858 DOI: 10.1080/10256016.2015.1026339

Nasarawa State is located in north central Nigeria and it is known as Nigeria's home of solid minerals. It is endowed with barite, copper, zinc, tantalite and granite. Continuous releases of mining waste and tailings into the biosphere may result in a build-up of radionuclides in air, water and soil. This work therefore aims to measure the activity concentration levels of primordial radionuclides in the soil/sediment samples collected from selected mines of the mining areas of Nasarawa State. The paper also assesses the radiological and radio ecological impacts of mining activities on the residents of mining areas and their environment. The activity concentrations of primordial radionuclides ((226)Ra, (232)Th and (40)K) in the surface soils/sediment samples were determined using sodium iodide-thallium gamma spectroscopy. Seven major mines were considered with 21 samples taken from each of the mines for radiochemistry analysis. The human health hazard assessment was conducted using regulatory methodologies set by the United Nations Scientific Committee on the Effects of Atomic Radiation, while the radio ecological impact assessment was conducted using the ERICA tool v. 1.2. The result shows that the activity concentrations of (40)K in the water ways of the Akiri copper and the Azara barite mines are 60 and 67% higher than the world average value for (40)K, respectively. In all mines, the annual effective dose rates (mSv y(-1)) were less than unity, and a maximum annual gonadal dose of 0.58 mSv y(-1) is received at the Akiri copper mine, which is almost twice the world average value for gonadal dose. The external hazard indices for all the mines were less than unity. Our results also show that mollusc-gastropod, insect larvae, mollusc-bivalve and zooplankton are the freshwater biotas with the highest dose rates ranging from 5 to 7 µGy h(-1). These higher dose rates could be associated with zinc and copper mining at Abuni and Akiri, respectively. The most exposed terrestrial reference organisms are lichen and bryophytes. In all cases, the radio ecological risks are not likely to be discernible. This paper presents a pioneer data for ecological risk from ionizing contaminants due to mining activity in Nasarawa State, Nigeria. Its methodology could be adopted for future work on radioecology of mining.

Matched MeSH terms: Radiation Exposure*
ASSESSMENT OF PATIENT'S RADIATION EXPOSURES RESULTED FROM PET/CT 18F-FCH AND 68GA-PSMA PROCEDURES

Salah H, Al-Mohammed HI, Mayhoub FH, Sulieman A, Alkhorayef M, Abolaban FA, et al.

Radiat Prot Dosimetry, 2021 Oct 12;195(3-4):349-354.
PMID: 34144608 DOI: 10.1093/rpd/ncab077

This study has sought to evaluate patient exposures during the course of particular diagnostic positron emission tomography and computed tomography (PET/CT) techniques. A total of 73 patients were examined using two types of radiopharmaceutical: 18F-fluorocholine (FCH, 48 patients) and 68Ga-prostate-specific membrane antigen (PSMA, 25 patients). The mean and range of administered activity (AA) in MBq, and effective dose (mSv) for FCH were 314.4 ± 61.6 (462.5-216.8) and 5.9 ± 1.2 (8.8-4.11), respectively. Quoted in the same set of units, the mean and range of AA and effective dose for 68Ga-PSMA were 179.3 ± 92.3 (603.1-115.1) and 17.9 ± 9.2 (60.3-11.5). Patient effective doses from 18F-FCH being a factor of two greater than the dose resulting from 68Ga-PSMA PET/CT procedures. CT accounts for some 84 and 23% for 18F-FCH and 68Ga-PSMA procedures, accordingly CT acquisition parameter optimization is recommended. Patient doses have been found to be slightly greater than previous studies.

Matched MeSH terms: Radiation Exposure*
Ensuring radiation safety: Evaluating dose and compliance among medical staff at King Faisal Medical Complex, Saudi Arabia

Hassan WB, Osman H, Alosaimi M, AbuRkbah A, AlQurashi A, Elkhader BA, et al.

Appl Radiat Isot, 2024 Sep;211:111386.
PMID: 38870555 DOI: 10.1016/j.apradiso.2024.111386

BACKGROUND: Radiation is an integral part of routine medical practice, but it carries a risk to the health of medical staff. Hence, it should be assessed periodically. The study's goal was to quantify the levels of radiation exposure for medical staff at King Faisal Medical Complex (KFMC), Taif City Saudi Arabia, and to assess their radiation protective procedures in practice.
METHODS: The study looked at the thermoluminescence dosimeters (TLDs) records of 50 medical professionals who were exposed to radiation while working at KFMC from 2019 to 2020 in Taif city, Saudi Arabia. In Riyadh, radiation exposure is read from skin TLDs using Harshaw model 6600 plus detectors. The Excel software was utilized to process the obtained data for calculating effective doses. A questionnaire was also distributed to the medical staff to assess their radiation protection procedures. The Statistical Package for Social Sciences (SPSS) program version 23 was used to analyze the obtained data.
RESULTS: The mean annual effective doses of the medical staff in 2019 and 2020 were determined to be 1.14 mSv and 1.4645 mSv, respectively, with no significant difference in effective doses between males and females in either year. The socio-demographic features of the medical personnel were examined, and the findings revealed that the majority of participants were male radiological technologists. The rate of adherence to radiation protection techniques was 68%, with a normally distributed dispersal. The amount of adherence varied significantly depending on nationality, occupation, and academic qualification.
CONCLUSION: According to the research, the mean annual effective dosage for medical professionals at KFMC was significantly below the recommended level, indicating satisfactory compliance with the ALARA radiation safety concept.

Matched MeSH terms: Radiation Exposure/analysis
Assessment of impact of urbanisation on background radiation exposure and human health risk estimation in Kuala Lumpur, Malaysia

Sanusi MSM, Ramli AT, Hassan WMSW, Lee MH, Izham A, Said MN, et al.

Environ Int, 2017 07;104:91-101.
PMID: 28412010 DOI: 10.1016/j.envint.2017.01.009

Kuala Lumpur has been undergoing rapid urbanisation process, mainly in infrastructure development. The opening of new township and residential in former tin mining areas, particularly in the heavy mineral- or tin-bearing alluvial soil in Kuala Lumpur, is a contentious subject in land-use regulation. Construction practices, i.e. reclamation and dredging in these areas are potential to enhance the radioactivity levels of soil and subsequently, increase the existing background gamma radiation levels. This situation is worsened with the utilisation of tin tailings as construction materials apart from unavoidable soil pollutions due to naturally occurring radioactive materials in construction materials, e.g. granitic aggregate, cement and red clay brick. This study was conducted to assess the urbanisation impacts on background gamma radiation in Kuala Lumpur. The study found that the mean value of measured dose rate was 251±6nGyh-1(156-392nGyh-1) and 4 times higher than the world average value. High radioactivity levels of238U (95±12Bqkg-1),232Th (191±23Bqkg-1,) and40K (727±130Bqkg-1) in soil were identified as the major source of high radiation exposure. Based on statistical ANOVA, t-test, and analyses of cumulative probability distribution, this study has statistically verified the dose enhancements in the background radiation. The effective dose was estimated to be 0.31±0.01mSvy-1per man. The recommended ICRP reference level (1-20mSvy-1) is applicable to the involved existing exposure situation in this study. The estimated effective dose in this study is lower than the ICRP reference level and too low to cause deterministic radiation effects. Nevertheless based on estimations of lifetime radiation exposure risks, this study found that there was small probability for individual in Kuala Lumpur being diagnosed with cancer and dying of cancer.

Matched MeSH terms: Radiation Exposure/analysis*
Fulltext Towards holistic radiation protection. lessons from the literatures

Zainul Ibrahim Bin Zainuddin

International Journal of Allied Health Sciences, 2018;2(3):517-527.
MyJurnal

The effects of radiation on man and his health had been noticed since the early years after the discovery of X-rays. These biological concerns were more commonly known as “radio-sensitiveness” in the early publications. Later, the term radiation protection was introduced to express the need for protective measures to be promoted, formulated, implemented, evaluated and sustained to reduce the biological effects associated with radiation exposure. The principles of radiation protection were then supported with the concepts of justification, ALARA and “Benefits against the risks”. But these could not ensure that the application of radiation protection has been optimized. Amidst the technological advancements associated with radiation based imaging modalities in healthcare for more than 120 years, those advancements have yet to be able reduce the impact of these modalities being a source of risks upon the more beneficial role as a
diagnostic tool. This paper reports a review on radiation protection from articles indexed in an online database. Considering that the titles of the articles contain the core subject matter that a publication carries, data were retrieved on those titles with the term “radiation protection”. Publications from 2008 to middle of November 2017 and aligned to Medicine and Health professions were included for further elaborations. The data were classified into four subject areas; education and training, administration and organization, practice and research. Discussions within each classification and their individual sub-classifications, supported by selected publications to the classification, highlight the importance of the particular subject area to the overall concept of radiation protection. Lessons learnt from the classifications could provide the necessary guidance on how one should adopt and adapt the concept of radiation protection holistically. The discussions that are presented are seen within the professional obligation in adhering to the principles of
radiation protection.

Matched MeSH terms: Radiation Exposure
Fulltext Contribution of Selangor and Johor clay bricks towards the natural radioactivity exposure to dweller

Na’im Syauqi Hamzah, Redzuwan Yahaya, Amran Ab. Majid, Muhammad Samudi Yasir, Ismail Bahari

Journal of Nuclear and Related Technologies, 2010;2010(1):40-48.
MyJurnal

At present, soil and mineral based building material such as bricks are one of the main components in building construction in Malaysia. This building material is a direct source of radiation exposure since it contains naturally occurring radioactive materials (NORM). In this study, clay brick samples used were obtained from 7 factories in Selangor and Johore, Malaysia. The activity concentrations of 226 Ra, 232 Th and 40 K in these samples of clay bricks were determined using a comparative method and was analysed using gamma spectrometry with HPGe detector. The mean values of activity concentrations for 226 Ra, 232 Th and 40 K were found to be in the range of 39.04 ± 0.88 Bqkg-1 - 73.61 ± 5.32 Bqkg-1, 43.38 ± 2.60 Bqkg-1 - 73.45 ± 1.51 Bqkg-1, and 381.54 ± 11.39 Bqkg-1 - 699.63 ± 15.82 Bqkg-1, respectively. The radiation hazard of NORM in the samples was estimated by calculating the radium equivalent activity (Raeq), external hazard index (Hex) and internal hazard index (Hin). Radium equivalent activity (Raeq) determined was in the range of 151.90 Bqkg-1 - 194.22 Bqkg-1 which is lower than the limit of 370 Bqkg-1 (equivalent to 1.5 mSvyr-1 ) recommended in the NEA-OECD report in 1979, whereas external hazard index (Hex) and internal hazard index (Hin) were between 0.20 – 0.26 and 0.52 - 0.71 respectively. The annual effective dose rate exposure to a dweller received from the clay bricks was calculated to be in the range of 0.35 ± 0.18 mSvy-1 - 0.43 ± 0.09 mSvy-1.

Matched MeSH terms: Radiation Exposure
Fulltext Measurement of extremely low frequency (ELF) magnetic flux in the vicinity of the overhead high voltage transmission line in Universiti Kebangsaan Malaysia

Faizal Mohamed, Irman Abdul Rahman, Ngu, Thieng Kui, Syazwani Mohd Fadzil, Firdaus Pozi, Amran Ab. Majid, et al.

Journal of Nuclear and Related Technologies, 2017;14(2):1-10.
MyJurnal

Electricity has become one of the necessities for human daily activities. The presence of electric
current produces electromagnetic fields (EMF) at extremely low frequency (ELF). The problem arises
when scientists suggests a possible connection between ELF exposure to human health and safety.
Concerned about the safety and health of students and staff, Universiti Kebangsaan Malaysia (UKM)
took the initiative to identify possible ELF sources and measure their exposure in various locations
around the UKM main campus in Bangi. This paper reports the results obtained from the monitoring
of the magnetic flux density at three identified locations in the vicinity of the overhead high-voltage
transmission line which transverses the university compound and compare the maximum value results
with the exposure limit suggested by the International Committee on Non Ionising Radiation
Protection (ICNIRP) for ELF. Measurements were done with an (Extech) Three Axis
Electromagnetic Field (EMF) Meter (Model 430826) to determine the magnetic flux density. The
lateral profile method was applied as the standard measurement methodology. Results showed that the
maximum value of the magnetic flux density was 12.5 mG, which is below the suggested ICNIRP
public exposure limit of 1000 mG, or in percentage ratio, 1.25% of ICNIRP public exposure limit.
Results from the statistical Kruskal-Wallis test showed that there is a significant difference in the
distributions of the magnetic flux densities at the different locations (P < 0.05). In conclusion, the
measured locations are still safe for people in short-term exposure. However, long-term exposure
measurements still need to be done to provide concrete data on the ELF-emission levels in UKM.

Matched MeSH terms: Radiation Exposure
EVALUATION OF RADON CONCENTRATION IN IRRIGATION AND DRINKING WATERS FROM THE EASTERN PART OF OMAN AND ESTIMATION OF EFFECTIVE DOSES TO OMANIS

Nasser SM, Khandaker MU, Bradley DA, Isinkaye MO

Radiat Prot Dosimetry, 2019 Oct 01;184(3-4):422-425.
PMID: 31038706 DOI: 10.1093/rpd/ncz088

The present study concerns measurement of the radon concentration in drinking and irrigation waters obtained from the eastern part of Oman, in particular in regard to water quality assessment of the region. The samples were collected from different places covering most types of water sources in the region. A passive and time-integrated track etch detector (LR-115 type II) combined with a high-resolution optical microscope has been used to obtain the radon concentration in the studied samples. Values of dissolved radon in water varied among the water sources; the highest concentration of radon was found to be 363 Bq m-3 in a drinking water sample while well water used for irrigation showed the lowest value, at 140 Bq m-3. Measured data for all water sources are below the permissible limit of 11.1 kBq m-3 recommended by the US-EPA. Annual effective doses for the studied samples were in the range 0.38-0.99 μSv y-1 which is significantly less than the action level recommended by the WHO (0.1 mSv y-1), indicating that the water sources in the Jalan BBH region of Oman are safe to use. The obtained data may serve as a reference for any future radiological study of the waterbody of this region.

Matched MeSH terms: Radiation Exposure/analysis*
Patient Exposure during Fluoroscopy-guided Pacemaker Implantation Procedures

Alkhorayef M, Sulieman A, Babikir E, Daar E, Alnaaimi M, Alduaij M, et al.

Appl Radiat Isot, 2018 Aug;138:14-17.
PMID: 28830729 DOI: 10.1016/j.apradiso.2017.08.010

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 (Gycm2) 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 1.1mSv 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.

Matched MeSH terms: Radiation Exposure/analysis; Radiation Exposure/prevention & control
Fulltext A survey of radiation dose to patients and operators during radiofrequency ablation using computed tomography

Saidatul A, Azlan C, Megat Amin M, Abdullah B, Ng Kh

Biomed Imaging Interv J, 2010 Jan-Mar;6(1):e1.
PMID: 21611060 MyJurnal DOI: 10.2349/biij.6.1.e2

Computed tomography (CT) fluoroscopy is able to give real time images to a physician undertaking minimally invasive procedures such as biopsies, percutaneous drainage, and radio frequency ablation (RFA). Both operators executing the procedure and patients too, are thus at risk of radiation exposure during a CT fluoroscopy.This study focuses on the radiation exposure present during a series of radio frequency ablation (RFA) procedures, and used Gafchromic film (Type XR-QA; International Specialty Products, USA) and thermoluminescent dosimeters (TLD-100H; Bicron, USA) to measure the radiation received by patients undergoing treatment, and also operators subject to scatter radiation.The voltage was held constant at 120 kVp and the current 70mA, with 5mm thickness. The duration of irradiation was between 150-638 seconds.Ultimately, from a sample of 30 liver that have undergone RFA, the study revealed that the operator received the highest dose at the hands, which was followed by the eyes and thyroid, while secondary staff dosage was moderately uniform across all parts of the body that were measured.

Matched MeSH terms: Radiation Exposure
Fulltext Repeat rate analysis of lower limb radiograph for digital radiography in general radiography at Pantai Klang hospital Selangor

Nur Aishah Jusnaidi, Nurul Fadhlina Ismail

Malaysian Journal of Applied Sciences, 2020;5(2):112-116.
MyJurnal

Assessing the repeat rate is crucial to reduce unnecessary dose to the patient by identifying the major cause for repeating the x-rays exposure to the patient and apply corrective measures. To analyse the repeat rate of routine lower limb projections in direct digital radiography (DR) from general radiology department of Pantai Klang Hospital. 26 months retrospective repeated radiograph was acquired from Picture Archiving and Communication System (PACS) at Hospital Pantai Klang. The retrieved radiographs were grouped based on the reason for the i radiographs being rejected which are incorrect positioning, incorrect collimation, patient movement, incorrect exposure factors, artefact, and other reasons. Total repeated radiographs retrieved for basic lower limbs projections were 13616. Knee was the highest repeted examination and the lowest repeat rate was tibia fibula. (repeat rate: knee = 1.04%, tibia fibula = 0.57%). incorrect positioning is the major causes for repeat exposure for all examinations type, followed by incorrect collimation, other categories, centring ray error, incorrect exposure factors and artifact.

Matched MeSH terms: Radiation Exposure
Fulltext Transparent Blend of Poly(Methylmethacrylate)/Cellulose Acetate Butyrate for the Protection from Ultraviolet

Mahmood Raouf R, Abdul Wahab Z, Azowa Ibrahim N, Abidin Talib Z, Chieng BW

Polymers (Basel), 2016 Apr 14;8(4).
PMID: 30979233 DOI: 10.3390/polym8040128

The use of transparent polymers as an alternative to glass has become widespread. However, the direct exposure of these materials to climatic conditions of sunlight and heat decrease the lifetime cost of these products. The aim of this study was to minimize the harm caused by ultraviolet (UV) radiation exposure to transparent poly(methylmethacrylate) (PMMA), which usually leads to changes in the physical and chemical properties of these materials and reduced performance. This was achieved using environmentally friendly cellulose acetate butyrate (CAB). The optical, morphological, and thermal properties of CAB blended with transparent PMMA was studied using UV-VIS spectrophotometry, scanning electron microscopy, X-ray diffraction, dynamic mechanical analysis, and thermal gravimetric analysis. The results show that CAB was able to reduce the effects of UV radiation by making PMMA more transparent to UV light, thereby preventing the negative effects of trapped radiation within the compositional structure, while maintaining the amorphous structure of the blend. The results also show that CAB blended with PMMA led to some properties commensurate with the requirements of research in terms of a slight increase in the value of the modulus and the glass transition temperature for the PMMA/CAB blend.

Matched MeSH terms: Radiation Exposure
Personalized administration of contrast medium with high delivery rate in low tube voltage coronary computed tomography angiography

Tan SK, Ng KH, Yeong CH, Raja Aman RRA, Mohamed Sani F, Abdul Aziz YF, et al.

Quant Imaging Med Surg, 2019 Apr;9(4):552-564.
PMID: 31143647 DOI: 10.21037/qims.2019.03.13

Background: High delivery rate is an important factor in optimizing contrast medium administration in coronary computed tomography angiography (CCTA). A personalized contrast volume calculation algorithm incorporating high iodine delivery rate (IDR) can reduce total iodine dose (TID) and produce optimal vessel contrast enhancement (VCE) in low tube voltage CCTA. In this study, we developed and validated an algorithm for calculating the volume of contrast medium delivered at a high rate for patients undergoing retrospectively ECG-gated CCTA with low tube voltage protocol.
Methods: The algorithm for an IDR of 2.22 gI·s-1 was developed based on the relationship between VCE and contrast volume in 141 patients; test bolus parameters and characteristics in 75 patients; and, tube voltage in a phantom study. The algorithm was retrospectively tested in 45 patients who underwent retrospectively ECG-gated CCTA with a 100 kVp protocol. Image quality, TID and radiation dose exposure were compared with those produced using the 120 kVp and routine contrast protocols.
Results: Age, sex, body surface area (BSA) and peak contrast enhancement (PCE) were significant predictors for VCE (P<0.05). A strong linear correlation was observed between VCE and contrast volume (r=0.97, P<0.05). The 100-to-120 kVp contrast enhancement conversion factor (Ec) was calculated at 0.81. Optimal VCE (250 to 450 HU) and diagnostic image quality were obtained with significant reductions in TID (32.1%) and radiation dose (38.5%) when using 100 kVp and personalized contrast volume calculation algorithm compared with 120 kVp and routine contrast protocols (P<0.05).
Conclusions: The proposed algorithm could significantly reduce TID and radiation exposure while maintaining optimal VCE and image quality in CCTA with 100 kVp protocol.

Matched MeSH terms: Radiation Exposure
Fulltext Determination of radon activity concentration in water using liquid scintillation counting technique

Zaini Hamzah, Ahmad Saat, Mohammed Kassim

Journal of Nuclear and Related Technologies, 2011;2011(1):33-38.
MyJurnal

Many studies were carried out throughout the world on radon measurement in water especially drinking water for it can cause problem to human health. This study is an attempt to measure the level of radon present in water collect from rivers and lakes. Data gathered from this study provides important information about radiation levels in water at selected sites, because radon gas is the largest contributor to natural radioactive radiation exposure to humans. Exposure to radon gas can cause lung cancer. Liquid scintillation counting (LSC) has been applied to determine the activity concentration of radon ( 222 Rn) in water. Water samples were collected from, ex-mining lake in Perak, Sok River in Kelantan, Tembeling River in Pahang. Water samples were prepared in polyethylene bottles mixed with liquid scintillator and stored for 3 weeks to allow 222 Rn and its progeny to reach the equilibrium, and the activity concentrations ranged from 0.24-1.27 Bq/L, and 0.029 – 0.155 Bq/L for radon and radium respectively.

Matched MeSH terms: Radiation Exposure
Radiation Exposure in Patients with Inflammatory Bowel Disease: a Fourteen-Year Review at a Tertiary Care Centre in Malaysia

Naidu J, Wong Zh, Palaniappan Sh, Ngiu ChS, Yaacob NY, Abdul Hamid H, et al.

Asian Pac J Cancer Prev, 2017 04 01;18(4):933-939.
PMID: 28545190

Background and Aims: Patients with inflammatory bowel disease (IBD) are subjected to a large amount of ionizing
radiation during the course of their illness. This may increase their risk of malignancy to a greater level than that due
to the disease itself. In Caucasian patients with Crohn’s disease, this has been well documented and recommendations
are in place to avoid high radiation imaging protocols. However, there are limited data available on radiation exposure
in Asian IBD patients.We therefore sought to identify total radiation exposure and any differences between ethnically
diverse ulcerative colitis (UC) and Crohn’s disease (CD) patients at our centre along with determining factors that may
contribute to any variation. Methods: The cumulative effective dose (CED) was calculated retrospectively from 2000
to 2014 using data from our online radiology database and patients’ medical records. Total CED in the IBD population
was measured. High exposure was defined as a radiation dose of greater than 0.2mSv (equivalent to slightly less than
½ a year of background radiation). Results: A total of 112 cases of IBD (36 CD and 76 UC) were reviewed. Our CD
patients were diagnosed at an earlier age than our UC cases (mean age 26.1 vs 45.7). The total CED in our IBD population
was 8.53 (95% CI: 4.53-12.52). Patients with CD were exposed to significantly higher radiation compared to those
with UC. The mean CED was 18.6 (7.30-29.87) and 3.65 (1.74-5.56, p=0.01) for CD and UC patients respectively. 2
patients were diagnosed as having a malignancy during follow up with respective CED values of 1.76mSv and 10mSv.
Conclusions: CD patients, particularly those with complicated disease, received a higher frequency of diagnostic
imaging over a shorter period when compared to UC patients. Usage of low radiation imaging protocols should be
encouraged in IBD patients to reduce their risk of consequent malignancy.

Matched MeSH terms: Radiation Exposure
Staff and ambient radiation dose resulting from therapeutic nuclear medicine procedures

Alkhorayef M, Sulieman A, Mohamed-Ahmed M, Al-Mohammed HI, Alkhomashi N, Sam AK, et al.

Appl Radiat Isot, 2018 Nov;141:270-274.
PMID: 30145016 DOI: 10.1016/j.apradiso.2018.07.014

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.

Matched MeSH terms: Radiation Exposure

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