National Radiological Protection Board Research Articles

Evaluasi Kualitas Radiograf Periapikal Teknik Bisektris : Kesalahan Penempatan Sudut Penyinaran dan Film

Background: The bisecting angle technique of periapical radiography is more often used in dental practice because the technique is practically adjustable and the patient's ability to adapt is better. Radiograph results are influenced by operator and patient factors, so management that is not optimal can cause a decrease in the quality of the radiograph, which affects interpretation, diagnosis, and treatment planning. The study aimed to determine the quality and frequency of errors in periapical radiographs using the bisecting technique due to errors in X-ray angulation and film placement at the Soelastri Dental and Oral Hospital (RSGM), University of Muhammadiyah Surakarta (UMS).Methods: The type of research is descriptive observational quantitative research with a retrospective approach. A total of 300 bisecting technique periapical radiographs from patients at RSGM Soelastri UMS in January–December 2021 who met the inclusion and exclusion criteria were taken in random stratification and evaluated. Radiographs are compared to ideal quality and given a National Radiological Protection Board (NRPB) rating, as well as looking at the frequency of errors that occur.Results: The rating most often obtained on periapical radiographs using the bisecting technique in the study was 2 for 181 radiographs (60.33%). The frequency of X-ray angulation errors was 62.94%, while the frequency of film placement errors was 37.06%. The highest error in X-ray angulation was cone cutting at 49.13%, while the error in film placement was in the form of apical cuts at 25.65%.Conclusions: The quality of periapical radiographs using the bisecting technique at the Radiology Installation at RSGM Soelastri UMS in the period January to December 2021 generally has a rating of 2 (diagnostically acceptable) according to the NRPB, and errors are still found in the angulation of the X-ray tube and film placement.

Radiation exposure assessment in coronary angiography computed tomography scan: Establishing diagnostic reference level for northeast Assam population

Background/Aim: Coronary angiography computed tomography (CT) scans play a pivotal role in diagnosing cardiovascular diseases, providing crucial information for treatment planning. However, concerns regarding radiation exposure have prompted the need for establishing region-specific diagnostic reference levels (DRLs) to ensure patient safety. This study aimed to assess radiation exposure during coronary angiography CT scans in the northeast Assam population and establish DRLs tailored to this demographic. Methods: A total of 380 patients were referred to the Primus Diagnostic Centre and Heath City Hospital, Guwahati Assam with coronary artery disturbances. Data on the technical parameters used in CT procedures were taken in 2021-2022. Organ and surface dose to specific radiosensitive organs (chest) estimation was done using software imPACT 1.0.4 from the National Radiological Protection Board (NRPB) SR250 Monte Carlo dataset. Results: The study population (n = 380) comprised 190 men and 190 women with an age range from 29 to 75 years. The mean body mass index (BMI) and effective dose (ED) were 22.42 ± 1.06 kg/m 2 and 21.57 ± 4.27 mSv.cm, respectively. The mean the dose-length product (DLP) was 854.67 mSv.cm and the mean ED was 21.57 mSv.cm. The ED for males was 13-27 mSv and 13-29 mSv for females. The DRL for the male population was found to be 24.26 mSv.cm 2 whereas for the female population was 24.69 mSv.cm 2 . Conclusion: This study highlights the necessity of establishing tailored DRLs for coronary angiography CT scans in the northeast Assam population. By doing so, healthcare providers can ensure optimal image quality while minimising radiation exposure, ultimately enhancing patient safety and quality of care. These findings have implications for radiological practice in the region and contribute to the ongoing efforts to standardise radiation doses in medical imaging procedures.

Assessment of Panoramic Radiograph Errors: An Evaluation of Patient Preparation and Positioning Quality at Soelastri Dental and Oral Hospital

Background: Dental radiography is an important component of comprehensive patient care. One of the most frequently used extraoral radiographic techniques is panoramic radiography. Panoramic radiographs lose value when the quality of the diagnostic radiographs is poor. In their application, there are still many errors that occur in panoramic radiographs. Objective: This study aimed to determine the quality and frequency of panoramic radiograph errors due to patient preparation and positioning errors at the Soelastri Dental and Oral Hospital, Universitas Muhammadiyah Surakarta (RSGM Soelastri UMS), Indonesia. Methods: This type of research is descriptive, quantitative, observational, and takes a retrospective approach. A total of 312 panoramic radiographs of patients at RSGM Soelastri UMS from January to December 2021 who met the inclusion and exclusion criteria were taken at random stages and evaluated. Radiographs were compared with ideal quality, given a National Radiological Protection Board (NRPB) rating, and the frequency of errors that occurred was evaluated. Results: The most common rating obtained on panoramic radiographs in this study was 2 of 173 (55.45%). The frequency of preparation errors was 1.22%, while the frequency of patient position errors was 98.78%. The highest patient position error was not placing the tongue on the palate, which was 49.68%. Conclusion: The quality of panoramic radiographs at RSGM Soelastri UMS in the period from January–December 2021 generally has a rating of 2, according to the NRPB, and there are still errors in patient preparation and positioning.

Estimation of Effective Dose in Monte Carlo Simulation Method for CT Coronary Angiography Patients

Computed tomography (CT) scans of Coronary Angiography have significantly aided in the diagnosis of disorders of the coronary artery. In contrast to other radiological examinations, the patient's radiation exposure is notably higher. This study aimed to optimize the radiation dose and estimate the adequate amount in computed tomography (CT) for coronary angiography. A total of 380 patients were referred to the Primus Diagnostic Centre and Heath City Hospital, Guwahati Assam, during the study with coronary artery disturbances. Data on the technical parameters used in CT procedures were taken in 2022. The aim and study's objective was Organ and surface dose to specific radiosensitive organs (Chest) estimation using software imPACT 1.0.4 from National Radiological Protection Board (NRPB) SR250 Monte Carlo dataset. The study population (n = 380) comprised 190 men and 190 women with an average age of 29 to 75 years. The Mean ± SD of BMI and ED are 22.42±1.06 and 21.57±4.27 respectively. The mean DLP is 854.67, and the mean ED is 21.57. The effective doses for males (13- 27) mSv were in females (13-29) mSv. This study was a pioneer in presenting actual amounts of CT examinations in Assam because other countries have already started with more advanced CT procedures, such as dosages for paediatrics, coronary angiography and CT fluoroscopy. With this study, there may be more opportunities to create complex new studies or enhance the data from related studies that may be done in future work. The high precision with minimum risk, the current study can be considered as the need of the hour.

Analysis of endodontic dental records of patients who were treated in a public university in south of Brazil

Dental record has a fundamental role in dentist performance. This study evaluated the standard registration of dental records of patients submitted to endodontic treatment for undergraduate students (CG) and specialists endodontics students (CE) in a public university in the south of Brazil. The sample was obtained by convenience, consecutively and included dental records patients of a public university in the south of Brazil who were treated at CE and clinical records of patients who were treated at CG, during on the year 2014. Was analyzed the description of endodontic treatment, data retrieved was scored and rated using a modification of the scoring system proposed by Streiner & Norman (1996) and quality of radiographs was performed according to the guidelines of “National Radiological Protection Board”. At dental records were analyzed, 223 belong to CG and 219 belong CE. The records from CE and CG had similar information on the evaluated parameters, except for “presence of rubber dam” and “presence of abbreviature in the description” (Mann-Whitney Test, P = 0.386). The absence of periapical radiographs was higher in CE than CG records (CE = 36.77%; CG = 0.46%). (Mann-Whitney test, P<0.0001). There was a predominance of periapical radiographs with the grades “excellent” and “diagnostically acceptable” in both groups.The quality of records generally obtained good results. The incorporation of new science into the educational program like electronic records and digital imaging techniques, facilitating the constant updating of data related to health and treatment of patients improving the record of the evolution of procedures.

The Effect of Grain Size on Radon Exhalation Rate in Soil Samples of Dera Ismail Khan in Pakistan

Radon concentration and its exhalation rate has been measured from twenty five soil samples collected from seven different locations of Dera Ismail Khan, in the north west of Pakistan. These samples were crushed after drying and passed through sieves with different sizes of pores to get three grain sizes, £0.595 mm, 0.595-2.00 mm and 2.00-4.00 mm of soil. CR-39 based NRPB (National Radiological Protection Board) radon dosimeters have been used to measure the radon concentration and exhalation rates. The maximum average value of radon exhalation rate has found to be: (3.57±0.38) Bq m-2 hr-1 in the samples having grain size 2.00-4.00 mm and the minimum as: (2.21±0.26) Bq m-2hr-1, in the samples with grain size £ 0.0595 mm. This indicates that the radon exhalation rate increases with the grain size. The maximum average value of radon exhalation rate has been found in samples collected from river side where soil texture is silty clay loam. The obtained values of radon exhalation rate for all the samples are well below the world average value of 57.60 Bq m-2 hr-1.

Radiation exposure during therapeutic cardiac interventional procedures

The purpose the current work were to assess the radiation exposure given to patients during percutaneous coronary interventions (PCI), pacemaker (PM) and coronary angiography (CA), procedures. In total, 419 procedures were carried out in 4 specialized hospitals. Calibrated Kerma area product meters were used to quantify the patient doses. Effective dose was extrapolated using the national radiological protection board (NRPB) software program. The mean KAP (Gy.cm2) per procedure were 8.6, 6.2 and 5.6 for PCI, PM, and CA procedures, respectively. While in that order, e mean and Entrance Surface Air Kerma (ESAK, mGy) per procedure were 705.9,509, and 464.7 for PCI, PM, and CA. Patients’ doses is below the level of the deterministic effects and the effective dose per procedure is low. Patients radiation doses is lowest compared to the previous studies.

Biomarker of buccal mucosa cells damaged after exposure to panoramic radiography: a literature review

Objectives: This review aimed to understand the effect of exposure to panoramic radiographs on exfoliated buccal mucosal cells at the cellular level.
 Review: The dose of radiation exposure in dentistry, both intraoral and extraoral, has been regulated by The National Radiological Protection Board (NRPB). However, even though it is given in small doses, x-ray radiation due to intraoral and extraoral radiographs still has a radiobiological effect on the exposed tissue. The radiobiological effects of X-ray exposure can cause changes in biological molecules, either directly or indirectly, within hours or days. There are two classification of this radiobiological effect, called deterministic and stochastic effect. The deterministic effect occurs when the dose given exceeds the recommended dose by the NRPB, whereas the stochastic effect does not have any threshold that needs to be exceeded to give some adverse impact to the exposed tissue One method used as a predictor or biomarker of genetic damage due to exposure to physical or chemical mutagenic agents in humans is micronucleus (MN). The biomarker for the cell damaged is the change of nucleus shape and outline, called pycnosis, karyolysis, karyorrhexis.
 Conclusion: The exposed to x-ray from panoramic could induce cell and genetic damaged. Prescription for panoramic radiographic examination in patients should be as effectively as possible according to the principles of ALADA (as low as diagnostically acceptable) to avoid adverse effects on the exposed tissue.

Assessment of common errors and subjective quality of digital panoramic radiographs in a dental institution

Aim: The aim of the study was to determine the incidence of patient preparation and positioning errors during panoramic radiographic imaging and to assess the subjective quality of panoramic radiographs in a sample of records collected from a dental institution. Materials and Methods: The study material was 1000 randomly selected panoramic radiographs obtained from the database of the department of oral and maxillofacial radiology. Patient preparation and positioning errors of the radiographs were evaluated and categorized into nine groups. The sample radiographs were also evaluated for subjective quality according to a three-point quality scale by the National Radiological Protection Board (United Kingdom) as “excellent,” “diagnostically acceptable,” or “unacceptable.” Results: Out of 1000 radiographs evaluated, failure to position the tongue against palate was the most common error at 69.5% and patient movement during radiographic exposure was the least common error at 0.4%. As per the subjective quality ratings, 22.4% of the radiograph had excellent quality, 66.4% were diagnostically acceptable, and 13.2% were unacceptable. Conclusion: The incidence of patient positioning errors in the panoramic radiographs was relatively common. The quality of the diagnostic panoramic radiographs could be improved by better operator education and awareness in relation to patient preparation and positioning.

Radiation exposure during videofluoroscopic swallowing studies in young children

ObjectivesSwallowing difficulties are best assessed by videofluoroscopic swallowing studies (VFSS). However, limiting radiation exposure is important, especially in young children. The purpose was to evaluate radiation dose in young children during VFSS, and to investigate factors associated with it. MethodsChildren with swallowing difficulty who underwent VFSS from February 2012 to July 2014 were recruited. Dose area product (DAP) and screening time were offered by the fluoroscopy machine, and effective dose was calculated from the DAP using a conversion coefficient published by the National Radiological Protection Board (NRPB-R262). The age, gender, height, weight, body mass index (BMI), body surface area (BSA), underlying disease of the subject children, and results of VFSS were investigated. ResultsIn 89 children (mean age 1.57 ± 2.17, 55 boys and 34 girls), mean effective dose was 0.29 ± 0.20 mSv, mean DAP was 2.41 ± 1.65 Gy cm2, and mean screening time was 2.24 ± 0.99 min. The effective dose correlated with the screening time (r = 0.598, p < 0.001), age (r = 0.210, p = 0.049), height (r = 0.521, p < 0.001), weight (r = 0.461, p < 0.001), and BSA (r = 0.493, p < 0.001). There was no such correlation with gender, BMI, underlying disease, or the results of VFSS. ConclusionsThe effective dose during VFSS (0.29 mSv) in young children, which is affected by screening time, age, and body size, is considerably lower than the pediatric radiation exposure limit of 1 mSv per year. However more than 4 VFSS annually would exceed this limit. Our findings will help physicians to reduce the radiation exposure and provide a useful references for future pediatric VFSS guidelines.

Quality Analysis of Periapical Radiographs Taken by Dental Assistants

OBJECTIVE: To analyze the quality of intraoral periapical radiographs (IOPA) taken by dental assistants in the department of operative dentistry.METHODOLOGY: The study design was cross-sectional descriptive type, non-probability convenient sampling technique was used to achieve the calculated sample size. A total of 100 periapical radiographs were collected for evaluation from department of operative dentistry at Hamdard University Dental Hospital, Karachi. Pre, intra and post-operative radiographs were evaluated taken during endodontic therapy. National Radiological Protection Board recommended three point quality scale was used to analyze the IOPA radiographs into excellent, acceptable or unacceptable. The targets were set according to the “Guidance Notes for Dental Practitioners on the Safe Use of X-ray Equipment” recommendations.RESULTS: A total 100 radiographs were evaluated, 32% were classified as excellent, 45% diagnostically acceptable and 23% of the radiographs diagnostically unacceptable. Rejection rate analysis showed that incorrect film positioning was the most frequent fault resulting in missing or obscured coronal/apical area being the cause in 50% cases. CONCLUSION: It has been concluded that frequent quality assessment and monitoring of dental team and their training in dental radiography would help in achieving gold standards. Furthermore, following standard guidelines increase the quality of the radiographs and enhance safety practices.

Estimation of radiation-induced cataract and cancer risks during routine CT head procedures

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

Selection of bone dosimetry models for application in Monte Carlo simulations to provide CT scanner-specific organ dose coefficients

This is the second paper arising from a project concerning the application of Monte Carlo simulations to provide scanner-specific organ dose coefficients for modern CT scanners. The present focus is centred on the bone dosimetry models that have been developed. Simulations have been performed in photon only transport mode, with the assumption of electron equilibrium. This approximation breaks down for doses to active marrow and endosteum since the target cells are localised within tens of micrometre from bone tissue and dose enhancement functions are necessary to correct for the additional dose from photoelectric electrons created in adjacent material. The dose enhancement models used previously in publications NRPB-SR250 (Jones and Shrimpton 1993 Software Report NRPB-SR250, National Radiological Protection Board, Chilton, UK) and ORNL-TM8381 (Cristy and Eckerman 1987 Technical Report Oak Ridge National Laboratory, Oak Ridge, TN) have been implemented and compared with the contemporary approaches of Johnson et al (2011 Phys. Med. Biol. 56 2347–65) and ICRP Publication 116 (ICRP 2010 Ann. ICRP 40 1–257) that are being adopted in the present project. In addition, the calculation of dose to endosteum in the medullary cavity is reviewed and updated using electron mode simulations. For the purposes of quality assurance and comparison, the various dose enhancement functions have been applied in relation to the NRPB18+DJ and HPA18+ stylised hermaphrodite phantoms and also the adult male and female voxel phantoms recommended in ICRP Publication 110 (ICRP 2009 Ann. ICRP 39 1–165), for exposure from three CT scanners modelled previously. Contemporary results for standard examinations on the head and trunk calculated for these latter phantoms demonstrate moderate increases (modal value +18%) in active marrow dose coefficients relative to values derived from data published in NRPB-SR250. A similar analysis in relation to endosteum dose coefficients shows larger reductions (modal value −46%), owing at least in part to changes in assumed location of the target cells. Even larger changes are apparent for both of these dose coefficients in relation to examination of the upper legs (−39% and −94%, respectively). However, resultant changes in any values of effective dose will be less owing to the low weighting factors applied for these tissues.

ESTIMATION OF ADULT PATIENT DOSES FOR CHEST X-RAY EXAMINATIONS AND COMPARISON WITH DIAGNOSTIC REFERENCE LEVELS (DRLs).

The aim of this study was to evaluate the radiation doses to patient during chest (posterior anterior/and lateral) examinations. The study was performed in three public hospitals of İstanbul province with a total of 300 adult patients. Entrance surface dose (ESD) measurements were conducted on computed radiography, digital radiography and screen film system. ESD was estimated by using International Atomic Energy Agency (IAEA) model and Davies model which are the common indirect models. Results were compared with diagnostic reference levels from the European Commission, IAEA and National Radiological Protection Board. Although the results are compatible with the international diagnostic reference levels, they present variations between the hospitals. Dose variations for the same type of X-ray examination support the idea that further optimization is possible.

The rate of repeating X-rays in the medical centers of Jenin District/Palestine and how to reduce patient exposure to radiation

Abstract Reduction of the patient’s received radiation dose to as low as reasonably achievable (ALARA) is based on recommendations of radiation protection organizations such as the International Commission on Radiological Protection (ICRP) and the National Radiological Protection Board (NRPB). The aim of this study was to explore the frequency and characteristics of rejected / repeated radiographic films in governmental and private centers in Jenin city. The radiological centers were chosen based on their high volume of radiographic studies. The evaluation was carried out over a period of four months. The collected data were compiled at the end of each week and entered into a computer for analysis at the end of study. Overall 5000 films (images) were performed in four months, The average repeat rate of radiographic images was 10% (500 films). Repetition rate was the same for both thoracic and abdominal images (42%). The main reason for repeating imaging was inadequate imaging quality (58.2%) and poor film processing (38%). Human error was the most likely reason necessitating the repetition of the radiographs (48 %). Infant and children groups comprised 85% of the patient population that required repetition of the radiographic studies. In conclusion, we have a higher repetition rate of imaging studies compared to the international standards (10% vs. 4-6%, respectively). This is especially noticeable in infants and children, and mainly attributed to human error in obtaining and processing images. This is an important issue that needs to be addressed on a national level due to the ill effects associated with excessive exposure to radiation especially in children, and to reduce cost of the care delivered.

Local Diagnostic Reference Levels for Some Common Diagnostic X-Ray Examinations In Sabzevar County of Iran

Introduction: Diagnostic reference level (DRL) is a useful tool for the promotion of optimization. The national DRLs (NDRLs) are useful, brief, and robust guidelines for optimizing radiation protection in a country. The aim of this study was to extract the local DRLs (LDRLs) for some common radiologic examination in Sabzevar county. Materials and Methods: There are eight radiology departments in Sabzevar County, Iran. The entrance skin dose (ESD) distributions were determined by use of thermoluminescence dosimeter (TLD) chips for 10 standard projections (i.e., anterioposterior [AP] abdomen, AP and posteroanterior [PA] chest, AP and lateral [LAT] lumbar spine, AP pelvis, cervical AP, cervical LAT, as well as AP and LAT skull). The third quartiles of the measured ESDs were compared with the previously published data. Results: In the present study, the third quartile of the measured ESDs for the patients undergoing specific examination were selected as LDRLs. The calculated LDRLs for the chest PA, chest AP, lumbar spine PA, lumbar spine LAT, pelvis AP, abdomen AP, cervical AP, cervical LAT, skull PA, and skull LAT were 0.54, 0.64, 1.99, 3.83, 1.47, 2.15, 0.54, 0.78, 1.22, and 1.01 mGy, respectively. Conclusion: Our results were compared with the DRLs reported in Iran, UK, and Japan as well as those reported by the National Radiological Protection Board (NPRB) for the UK. The ESDs obtained in this study for the chest PA, cervical AP, cervical LAT, AP and LAT skull, abdomen AP, pelvis AP, lumbar PA, and lumbar LAT examinations did not exceed the DRL values reported by NPRB.

Patient Exposure during Fluoroscopy-guided Pacemaker Implantation Procedures

A pacemaker, which is used for heart resynchronization with electrical impulses, is used to manage many clinical conditions. Recently, the frequency of pacemaker implantation procedures has increased to more than 50% worldwide. During this procedure, patients can be exposed to excessive radiation exposure. Wide range of doses has been reported in previous studies, suggesting that optimization of this procedure has not been fulfilled yet. The current study evaluated patient radiation exposure during cardiac pacemaker procedures and quantified the patient effective dose. A total of 145 procedures were performed for five pacemaker procedures (VVI, VVIR, VVD, VVDR, and DDDR) at two hospitals. Patient doses were measured using the kerma-area product meter. Effective doses were estimated using software based on Monte Carlo simulation from the National Radiological Protection Board (NRPB, now The Health Protection Agency). The effective dose values were used to estimate cancer risk from the pacemaker procedure. Patient demographic data and exposure parameters for fluoroscopy and radiography were quantified. The mean patient doses ± SD per procedure (Gy cm2) for VVI, VVIR, VVD, VVDR, and DDDR were 1.52 ± 0.13 (1.43–1.61), 3.28 ± 2.34 (0.29–8.73), 3.04 ± 1.67 (1.57–4.86), 6.04 ± 2.326 3.29–8.58), and 8.8 ± 3.6 (4.5–26.20), respectively. The overall patient effective dose was 1.1 mSv per procedure.It is obvious that the DDDR procedure exposed patients to the highest radiation dose. Patient dose variation can be attributed to procedure type, exposure parameter settings, and fluoroscopy time. The results of this study showed that patient doses during different pacemaker procedures are lower compared to previous reported values. Patient risk from pacemaker procedure is low, compared to other cardiac interventional procedures. Patients' exposures were mainly influenced by the type of procedures and the clinical indication.

Estimation of effective dose and radiation risk in pediatric barium studies procedures

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

Doses Evaluation of Some Body Organs of Pediatric Patients Undergoing Chest X-ray Examination Using Thermoluminescent dosimeter

Pediatric patients are among the most sensitive on ionizing radiation when they should be undergoing an X-Ray screening. The delivered dose to the pediatric patients should be well optimized to minimize the harmful effect of the X-Ray examinations. The objectives of this work are to measure at chest level and corresponding organ doses for each pediatric patient undergoing X-Ray radiation examination. The study was carried out in three hospitals in Madagascar. During these measurements, the patient doses were determined using thermo luminescent dosimeters (TLDs) placed upon to the patient’s body. The examination parameters (high voltage, filtration, field size and focus to skin distance examinations) for 114 patients undergoing chest examination with an Antero- Posterior (AP) projection have been collected. Entrance Surface Air Kerma (ESAK) was determined by using calibrated thermoluminescent dosimeters (TLD- 100) through the Secondary Standard Dosimetry Laboratory of Institut National des Sciences et Technique nucleaire- Madagascar. Patients population were categorized into four groups in accordance with their ages ([<1) year] (group 1), for group 2([1-5] years), for group 3([5-10] years) and for group 4([10-15] years).Values of organs doses vary following the age: the received dose increase inversely with the age of the patient. The breast received doses represents the maximum values compared with the other organs. Results of the ESAK have been used to evaluate the radiation dose levels for pediatric patients in Madagascar, to establish local diagnostic reference level and to optimize pediatric patient delivered doses. The patient organ received doses versus the dose at chest level have been determined by using National Radiological Protection Board (NRPB) coefficients through Visual Basic Application (VBA) tool.

Measurements of pediatric radiation exposure during barium imaging procedures

Radiological imaging has been considered a vital tool in the diagnosis of gastrointestinal tract (GIT) disorders. Gastrointestinal radiography (GIR) has been a major and first-choice method for diagnosing GIT diseases with barium as contrast media since its emergence in 1910. Radiographic examination of children, especially neonates, attracts particular interest because of the increased opportunity for expression of delayed radiogenic cancers as a consequence of relative longer life expectancy. Barium studies are of particular interest because it constitutes 5% of the total number of radiological examinations and 17% of the collective doses. Although, the task is important, there are few data on radiation doses to infants and children undergoing barium procedures. The current study intends to evaluate the radiation dose to pediatric patients during barium studies and to estimate the effective doses and radiation risk of the aforementioned procedures. A total of 43 pediatric barium procedures were performed in this study. 21.7% of the sample was barium meal, 8.6% were undergone barium swallow while 69.5% of the sample were barium enemas. Entrance surface air kerma (ESAKs) were calculated from patient exposure parameters using DosCal software. Effective doses (E) were calculated using published conversion factors and methods recommended by the national Radiological Protection Board (NRPB). The mean film numbers was 12.4, 8.9 and 8 for barium meal, barium enema and barium swallow, respectively. The maximum number of X rays was obtained in barium meal (21 film per a single procedure). The mean patient doses per procedure were 2.1 ± 0.8 mGy, 3.0 ± 23 mGy and 1.2 ± 0.2 mGy for barium meal, swallow and enema, respectively. The mean effective doses were 0.3 mSv, 1.0 mSv and 0.2 mSv at the same order. The dose values in this study were higher than previous studies. The unnecessary radiation exposure can be reduced significantly by reducing the number of films and screening time. Diagnostic reference level is recommended to improve the practice. Disclosure Authors have nothing to disclose.