Radiography Unit Research Articles

Comparison of the Operator and Surrounding Dose When Using Portable Intraoral X-ray Devices

This study aimed to investigate the scattered radiation dose using three portable dental radiographic units: iRay D3, EZRay Air, and Epix. The absorbed dose was measured at 0.5 and 1 m distances, every 15° in the horizontal plane, using an ionization chamber. The maximum number of radiographs per day using the portable units was calculated considering a dose limit of 50 mSv/year and 20 mSv/year. The doses were higher in the Epix unit compared to the other two devices. Anterior exposure was generally higher than the sides or posterior exposure. With a dose limit of 50 mSv/year, considering a distance of 0.5 m between the operator and the X-ray unit, a maximum of 961, 565, and 38 radiographs are permitted daily using iRay D3, EZRay Air, and Epix, respectively. Considering a dose limit of 20 mSv/year, with a distance of 0.5 m between the operator and the radiographic device, a maximum of 384, 226, and 15 radiographs are permitted daily using iRay D3, EZRay Air, and Epix portable units, respectively. It is highly unlikely that an operator would reach occupational dose limits when using iRay D3 and EZRay Air. The Epix radiographic device allows for fewer daily radiographs and should be avoided for daily use.

Survey on the dental age estimation practice among Brazilian experts

Screening experts’ practice and knowledge is a quality-control procedure to draw strategical actions towards the improve of services within the forensic routine. This study aimed to assess the forensic odontological facilities and knowledge of Brazilian experts regarding dental age estimation practice. A self-applicable 14-question survey addressing the demographic aspects, facilities and knowledge of Brazilian forensic odontologists was designed and sent to experts allocated all the geographic regions of Brazil. The questionnaire was answered by 28 forensic odontologists. Fifteen (83.33%) respondents had more than five dental age assessments per year, while 13 (72.22%) had less than five cases. The main reason behind dental age estimation practices in Brazil was human identification (n = 14; 50%). Fifteen (83.33%) respondents indicated that they have radiographic units. More dental age estimation cases were reported among experts of the Northeastern region (p = 0.03). The same region also had a higher report of radiological units (p = 0.04). Nicodemo’s and Lamendin’s methods were the most reported for the age assessment of children/adolescents and adults, respectively. The outcomes of the present study suggest that the Brazilian forensic odontologists might have at least the minimum equipment for dental age estimation of children, adolescents and adults.

Evaluation of the Inspection Cycle of Dental Diagnostic X-ray Equipment

All diagnostic X-ray equipments in dental clinics must undergo a radiation safety inspection upon initial installation and every three years thereafter. The objective of this study was to propose an appropriate inspection cycle based on the results of safety management inspection for dental diagnostic X-ray equipment.The subject of this study was the radiation safety management inspection results of 774 X-ray equipments at 88 dental clinics. The period of use of the X-ray equipment was analyzed using the device type, inspection date, installation date, manufacturing date, approval date, date of discontinuation of use, transfer date, and disposal date. The X-ray equipment composition comprised 477 intraoral units, 143 panoramic units, 134 CBCT units,and 20 other radiographic units. In equipment suitability classification, out of 774 devices, 98.7% (764 devices) were deemed suitable, and 1.3% (10 devices) were deemed unsuitable. Among the 10 unfit devices, one (0.8%) had a lifespan of 9 years, two (1.8%) had 12 years, three (5.4%) had 15 years, one (4.3%) had 18 years, two (18.2%) had 21 years, and one (100%) had 27 years.

Automatic image quality evaluation in digital radiography using for-processing and for-presentation images.

To investigate the impact of digital image post-processing algorithms on various image quality (IQ) metrics of radiographic images under different exposure conditions. A custom-made phantom constructed according to the instructions given in the IAEA Human Health Series No.39 publication was used, along with the respective software that automatically calculates various IQ metrics. Images with various exposure parameters were acquired with a digital radiography unit, which for each acquisition produces two images: one for-processing (raw) and one for-presentation (clinical). Various examination protocols were used, which incorporate diverse post-processing algorithms. The IQ metrics' values (IQ-scores) obtained were analyzed to investigate the effects of increasing incident air kerma (IAK) on the image receptor, tube potential (kVp), additional filtration, and examination protocol on image quality, and the differences between image type (raw or clinical). The IQ-scores were consistent for repeated identical exposures for both raw and clinical images. The effect that changes in exposure parameters and examination protocol had on IQ-scores were different depending on the IQ metric and image type. The expected positive effect that increasing IAK and decreasing tube potential should have on IQ was clearly exhibited in two IQ metrics only, the signal difference-to-noise-ratio (SDNR) and the detectability index (d'), for both image types. No effect of additional filtration on any of the IQ metrics was detected on images of either type. An interesting finding of the study was that for all different image acquisition selections the d' scores were larger in raw images, whereas the other IQ metrics were larger in clinical images for most of the cases. Since IQ-scores of raw and their respective clinical images may be largely different, the same type of image should be consistently used for monitoring IQ constancy and when results from different X-ray systems are compared.

Image reject analysis and rejection causes in digital radiography at a university hospital through estimates of patient doses.

The introduction of digital radiography has improved image acquisition. However, rejection of images remains a matter of concern. Reject analysis is part of the quality assurance program in radiology and helps identify potential errors or lack of training. A retrospective study was conducted at the radiology department of a university hospital. The reject rate was calculated both using the number of examinations, $r_n$, and the dose-area product, $r_d$. A reject rate $r_n$ of 3.3% for paediatric units and 4.5% for adults was found. The corresponding values of rd were 4.4 and 8.4%, respectively. The main rejection cause was patient motion, being 50.2% of rejected examinations in adults and 63.7% in children. The contribution of exposure errors was minor, as expected in digital radiography units. A discrepancy between reject rates $r_n$ and $r_d$ was observed, suggesting dosimetric quantities could be considered in reject analysis for further assessment of patient radiation burden.

Performance and reliability assessment of a lower dose, task-based scoliosis radiography protocol in pediatric patients.

Follow-up scoliosis radiographs are performed to assess the degree of spinal curvature and skeletal maturity, which can be done at lower radiation exposures than those in standard-dose radiography. Describe and evaluate a protocol that reduced the radiation in follow-up frontal-view scoliosis radiographs. We implemented a postero-anterior lower dose modified-technique for scoliosis radiography with task-based definition of adequate image quality and use of technique charts based on target exposure index and patient's height and weight. We subsequently retrospectively evaluated 40 consecutive patients who underwent a follow-up radiograph using the modified-technique after an initial standard-technique radiograph. We evaluated comparisons of proportions for subjective assessment with chi-squared tests, and agreements of reader's scores with intraclass correlation coefficients and Bland-Altman plots. We determined incident air kerma, exposure index, deviation index/standard deviation, dose-area product (DAP), and effective dose for each radiograph. We set statistical significance at P<0.05. Forty patients (65% female), aged 4-17years. Median effective dose was reduced from 39 to 10 µSv (P<0.001), incident air kerma from 139 to 29 µSv (P<0.001), and DAP from 266 to 55mGy*cm2 (P<0.001). All modified-technique parameters were rated with a mean score of acceptable or above. All modified-technique measurements obtained inter- and intra-observer correlation coefficient agreements of 0.86 ("Good") or greater. Substantial dose reduction on follow-up scoliosis imaging with existing radiography units is achievable through task-based definition of adequate image quality and tailoring of radiation to each patient's height and weight, while still allowing for reliable assessment and reproducible measurements.

Hard tissue density of permanent teeth as a radiometric biomarker of their quality

Background. The use of radiographic methods for examining patients with the ability to determine the density of examined tissues opens up wide opportunities for individually predicting damage to hard tissues of teeth, as well as determining risk groups for the development of their pathology at early stages, which requires a detailed study of the mineral density indicators of hard tissues of teeth of different groups within the norm, taking into account their age, sex, ethnic, and other characteristics. The aim of the study was to determine the density indicators of hard tissues of permanent teeth of different groups in the cervical area and compare them. Material and Methods. The density of hard tissues was determined by analyzing radiographs of 320 intact permanent teeth of 10 patients. Radiographs were made using a Siemens Sirona (XIOS XG Supreme, Germany) dental radiography unit with Trophy Radiologie software (version 7.0, Slovakia). The images were processed using Gendex VixWin Pro software (version 3.5, USA). The density was measured in Conditional Unit of Grayness (CUG). The results were presented as Me (25%; 75%), where Me represents the median, 25% denotes the 25th percentile (first quartile), and 75% denotes the 75th percentile (third quartile). Results. Incisors, canines, and premolars exhibited the highest density in the dentin area; the lowest density was observed in incisors and premolars for cementum and in canines for enamel. In molars, enamel had the highest density, while cementum had the lowest. Significant differences in enamel density were observed among incisors and premolars, incisors and molars, canines and premolars, canines and molars, and premolars and molars. Significant differences in dentin density were found among incisors and canines, incisors and premolars, incisors and molars, canines and premolars, and canines and molars. Significant differences in cementum density were observed among incisors and canines, incisors and premolars, incisors and molars, canines and premolars, and premolars and molars. Conclusion. The density indicators of enamel, dentin, and cementum established for groups of permanent incisors, canines, premolars, and molars are different for different tooth groups with characteristic density patterns. Keywords: enamel, dentin, cementum, incisors, canines, premolars, molars.

The effect of added filtration on radiation dose and image quality in digital radiography of newborns.

Repeated chest and/or abdomen radiographs are needed on mobile digital radiography (DR) units to assess infants' health status. Optimization of DR tube peak kilovoltage (kVp) and tube current time product (mAs) to derive images of diagnostic quality at as low as reasonably achievable radiation dose has been a challenging task. To investigate the effect of exposure parameters and additional filtration on entrance skin dose and image quality in newborn DR imaging. A physical anthropomorphic phantom that simulates the average full-term neonate was used. Chest and chest/abdomen DR images were acquired at the manufacturer's recommended kVp/mAs exposure parameters followed by a series of image acquisitions at different kVp/mAs and beam filtration combinations. Entrance skin dose (ESD) and signal difference to noise ratio (SdNR) for soft tissue, bone and feeding gastric tube were estimated in raw unprocessed images. A figure of merit (FOM) analysis provided the kVp/mAs and filtration that generated images of adequate quality at the lowest ESD. Signal difference increased with kVp and progressively decreased with increasing filtration. Compared to the manufacturer's recommended 53 kVp/1.6 mAs exposure parameters, ESD was reduced by 76% (47.61μGy versus 11.3μGy) in the chest and 66% (47.61μGy versus 16.14μGy) in the chest/abdomen when the exposure parameters and additional beam filtration provided by the FOM analysis were used. The results derived from this phantom study suggest that additional beam filtration along with the appropriate leverage of exposure parameters can lower ESD while maintaining image quality in full-term newborns.

Assessment of the Occupational Radiation Dose from a Handheld Portable X-ray Unit During Full-mouth Intraoral Dental Radiographs in the Dog and the Cat - A Pilot Study.

Occupational radiation protection is an important consideration in small animal clinics world-wide. With the increased use of portable handheld X-ray devices in veterinary dentistry, concerns related to occupational radiation protection are being raised. Annual occupational dose limits for dental workers are expressed as Total Dose Equivalent (TDE) or Effective Dose. The permitted TDE can vary depending on the anatomical region, ranging from 50 millisieverts (mSv) for the external whole body exposure dose to 500 mSv for external exposure of the skin or an extremity. Although several studies have been performed in human dentistry to establish the amount of backscatter radiation produced using portable handheld X-ray devices, no similar research has been conducted in veterinary dentistry. This study aimed to determine the TDE while acquiring a full mouth intraoral radiograph set in dogs and cats and to estimate the TDE for a handheld X-ray device's operator. For this, the backscatter radiation dose recorded by three sets of monitoring dosimeters located in strategic anatomical areas of the operator was assessed after taking one hundred intraoral radiographs in each group. The study concluded that the backscatter radiation levels were far below the permitted annual occupational doses in the three patient groups of this study. Even though the portable handheld X-ray unit was demonstrated to be a safe dental radiographic unit regarding backscattering radiation, the operator's eye, ovary, and breast regions were exposed to unnecessary radiation.

How to set up a mobile X-ray unit in the community - Implementation initiatives for patient-centred care

BackgroundMobile X-ray unit have previously been widely used within hospitals in general, predominately for imaging patients admitted to intensive care units or for patients who cannot tolerate a visit to the radiology department. It is now possible to have an X-ray examination outside the hospital in nursing homes or to bring the service to frail, vulnerable or disabled patients. A visit to the hospital can be a frightening experience for vulnerable patients living with dementia or other neurological disorder. It can potentially have a long-term impact on the patient's recovery or behaviour. This technical note aimed to provide insight into the planning and running of a mobile X-ray unit in a Danish setting. MethodsThis technical note draws on the lived experiences of radiographers operating and managing a mobile X-ray service, sharing experiences with the implementation process and the challenges and successes of a mobile X-ray unit. Results and key findingsSuccesses include that frail patient, especially those with dementia, benefit from mobile X-ray examinations, as they can remain in familiar surroundings during an X-ray procedure. In general, patients experienced an increased quality of life and less need for sedation medication due to anxiety. Also, working within a mobile X-ray unit is meaningful work for radiographers. Challenges included increased physicality of work, the funding required for the mobile unit, planning a communication strategy to the referring general practitioners, and permission from authorities to perform mobile examinations. ConclusionWe have successfully implemented a mobile radiography unit that provides a better service for vulnerable patients through learning from successes and challenges. Implications for practiceThe mobile radiography setup can benefit vulnerable patients and provide meaningful work for the radiographers. However, transportation of mobile radiography equipment outside the hospital includes many considerations and challenges.

Phenotyping the sheep tail - Presentation of characterization methods in the context of breeding for short-tailedness

In order to establish targeted breeding for short-tailedness, a suitable method must initially be found that allows phenotyping of the sheep tail beyond tail length. In this study, in addition to assessing body measurements, more advanced studies such as ultrasonography and radiology were performed on the caudal spine of sheep for the first time. The objective of this work was to analyze the physiological variation of tail lengths and vertebrae within a merino sheep population. It also aimed to validate the use of sonographic gray scale analysis and perfusion measurement on the sheep tail. Tail length and circumference in centimeters were measured in 256 Merino lambs on the first or second day of life. At 14 weeks of age the caudal spine of these animals was examined radiographically. Sonographic gray scale analysis and measurement of the perfusion velocity of the caudal artery mediana were also performed in a portion of the animals. The tested method of measurement showed a standard error of 0,08 cm and a coefficient of variation of 0,23% for tail length and 0,78% for tail circumference. The animals had a mean tail length of 22,5±2,32 cm and a mean tail circumference of 6,53±0,49 cm. The mean caudal vertebrae count for this population was 20,4±1,6. The use of a mobile radiographic unit is well suited for imaging the caudal spine in sheep. It was demonstrated that the caudal median artery could be imaged for measurement of perfusion velocity (cm/s), and sonographic gray-scale analysis also showed good feasibility. The mean gray scale value is 19,74±4,5 and the modal value for the most commonly found gray scale pixels is 191,53±120,2. The mean perfusion velocity for the caudal artery mediana is 5,83±3,04 cm/s. The results show that the methods presented are well suited for further characterization of the ovine tail. For the first time, gray values for the tail tissue and the perfusion velocity of the caudal artery mediana were determined.

Repeat Analysis Program As A Quality Assurance System For Radiology Management: Causal Repeat and Challenges

Rejected or repeated images analysis remains a significant challenge, particularly in digital imaging. Despite the expectation that the transition from conventional to digital systems would reduce repetition rates, the reality is that repetition rates still exceed established standards. This literature review aims to shed light on the identification of causes and barriers in the reject/repeat program. We conducted a systematic review of this program in radiography units over several decades, examining the causes of repetition, types of examinations, and data sources used. We also described the methods employed to analyze reject/repeat instances in both conventional and digital systems. The study found that computed or digital radiography was the primary data source for image analysis. Despite the use of digital systems, repetition rates persisted, with chest radiography being the most significant contributor, accounting for over 30% of cases. Technical factors, particularly positioning errors, contributed to more than 30% of repetitions. Notably, determining the causes of rejection proved subjective. However, one study highlighted that artificial intelligence (AI) could accurately predict image rejection with a sensitivity of 93%. Thus, the incorporation of AI can greatly assist in classifying rejection causes, resulting in more efficient and streamlined radiology management

Digital radiography image quality evaluation using various phantoms and software.

To investigate the effect of the exposure parameters on image quality (IQ) metrics of phantom images, obtained automatically using software or from visual evaluation. Three commercial phantoms and a homemade phantom constructed according to the instructions given in the IAEA Human Health Series No. 39 publication were used, along with the respective software that estimate automatically various IQ metrics. Images with various exposure parameters were acquired in a digital radiography (DR) unit. For the commercial phantoms, visual evaluations were also performed. The IQ scores obtained were analyzed to investigate the effects of increasing incident air kerma (IAK), tube potential (kVp), additional filtration, and acquisition protocol on IQ. The effects of the exposure parameters on the IQ metrics, determined with the commercial and the IAEA phantoms, were not the same. For example, clear trends of improvement of IQ scores with increased IAK and reduction of most IQ scores with increased kVp were observed mostly with the IAEA phantom, but not with the commercial phantoms (for both automatic and visual scoring methods). For all phantoms, the maximum variations in IQ scores observed for repeated identical exposures were almost always below 10% with automatic evaluation whereas, for visual evaluation, reached 17%. Failure to detect some expected trends with the complex commercial phantoms may be attributed to the fact that IQ in DR is more strongly affected by the post-processing procedures, which may mask the effect of other parameters on IQ, something that was not observed with the simple IAEA phantom.

Location Analysis for Additional Permanent Radiation Detector in X-Ray Radiography Unit

We have developed a Digital Fluorescence X-Ray Radiography prototype at the Department of Physics, Gadjah Mada University (UGM). The prototype should comply with radiation protection rules. Using an additional permanent dose detector to measure dose radiation indirectly is necessary. We indirectly controlled the dose analysis through a dose control chart from a permanent detector. We consider the Heel Effect in determining the position of the detector at the edge of the screen while reducing the scattered radiation and minimizing the difference to the reference point. The position of the detector follows a grid 5x5. The dose measurement will show the dose distribution pattern. It shows that the radiation dose at the edge point close to the cathode side has the closest dose value to the center point. The dose value variation at 70 kVp and 80 kVp is less than 5%. The dose value equation for the prototype is Gy = [(0.3579* kVp) -16.27] * mAs. A control chart will control that equation from the permanent detector to ensure that the dose value obtained is always valid. The Warning Limit (WL) dose from the control chart is 68.75 Gy, 63.99 Gy, and the Action Limit (AL) is 69.94 Gy and 62.80 Gy. The dose radiation monitoring may use the dose value equation controlled by a control chart from the permanent detector. Continuous reports on the dose value and the limit dose value are essential to ensure the health of the RSFD prototype.

Characterizing Scatter Correction Software of 5 Mobile Radiography Units

Bedside radiographs are usually obtained gridless, without a physical scatter correction grid because of several limitations. Therefore, multiple manufacturers of mobile radiography systems provide the possibility to apply scatter correction software (SC SW) on those images. The purpose of this study was to characterize different series of radiographs-gridless, SC SW, and physical grid-with an image quality assessment algorithm (IQAA). Furthermore, we investigated the potential dose reduction and the correlation between the output of the IQAA and the human observers. We obtained different series of radiographs with an anthropomorphic phantom (multipurpose chest phantom N1 "Lungman," Kyoto Kagaku, Kyoto, Japan). All radiographs were obtained with flat-panel detectors of 5 different manufacturers in a wall bucky system. An IQAA to analyze the radiographs was implemented in our department but was originally developed by the research group of the Duke University Medical Center. Seven physical quantities were calculated by the IQAA: rib-lung contrast (RLcontrast), subdiaphragm-lung contrast (SLcontrast), lung detail (Ldetail), mediastinum detail (Mdetail), lung noise (Lnoise), mediastinum noise (Mnoise), and rib-lung sharpness (RLsharpness). In a proof of concept, the results of the IQAA were validated by 3 experienced radiologists. Regression coefficients (b) of the linear regression model indicate that the human observer results correlate well with the IQAA (b ≥ 0.89, R2 ≥ 0.83). All manufacturers have SC SW that increases the 7 physical quantities of the gridless images. However, several manufacturers have SC SW that increases the physical metrics to the same level as the physical grid images. The SC SW radiographs obtained with a reduced tube load have an increased level of contrast, detail, sharpness, and noise compared with the gridless images obtained with the higher tube load. We have proven in a proof of concept that the originally developed IQAA can be used to characterize different series of images of different manufacturers. Based on the physical quantities, SC SW increases the contrast, detail, sharpness, and noise. The experimental results in this study assume a patient dose reduction could be possible when SC SW is applied.

Hospitals, field hospitals, community isolation centers, and finally home isolation

Unlike the first and second waves of COVID-19 pandemic in Thailand which were limited among certain populations in certain areas, the third wave starting in April 2021 spread nationwide. It was from less than 10 new cases a day in 2020, to be around 2,000 a day in June and then more than 20,000 new cases a day in August 2021. Among four doctors who were killed by COVID-19 during this third wave in Thailand, the Royal College of Radiologists of Thailand lost a very active and warm member, Associated Professor Wilaiwan Bhothisuwan. When hospitals and field hospitals were full, now COVID-19 infected patients were cared in community isolation centers. Home isolation, the last and probably the final form of health care, was set in this August. The Royal College of Radiologists of Thailand had launched a project “RadioVolunteer” to interpret and report chest radiographs of COVID-19 patients in prisons, field hospitals where there were shortage of radiologists, some community isolation centers, and radiographic units for patients with home isolation.

Local diagnostic reference levels for routine chest X-ray examinations at a public sector hospital in central South Africa.

BackgroundDose optimisation is a radiation protection guideline recommended by the International Commission on Radiological Protection (ICRP) for adherence to the ‘as low as reasonably achievable’ (ALARA) principle. Diagnostic reference levels (DRLs) are used to optimise patients’ radiation protection for diagnostic and interventional procedures and are particularly useful for frequently performed examinations such as chest X-rays.AimTo establish the local diagnostic reference levels (LDRLs) for routine chest X-rays.SettingPublic sector hospital, Northern Cape province, South Africa.MethodsSixty patients referred for chest X-rays fulfilling the inclusion criteria participated in this study. Patients were ≥ 18 years of age and weighed between 60 kg and 80 kg. Consent for participation was obtained. The entrance skin air kerma (ESAK) was measured by using the indirect method recommended by the International Atomic Energy Agency (IAEA). Statistical software (SAS version 9.2) was used to determine the LDRLs for chest X-rays in three different rooms. In two rooms, computed radiography (CR) was used and the other one was a digital radiography (DR) unit. The LDRL values at the research site were compared with various published international values.ResultsLDRLs for chest X-rays were established. The CR LDRL value for the posteroanterior (PA) chest projection was higher than the DR (flat panel detector [FPD]) LDRL value. The LDRLs of the PA chest projections were 0.3 mGy for CR and 0.2 mGy for DR. The lateral (LAT) chest projection LDRL value was 0.8 mGy for both CR and DR (FPD) projections. The resultant LDRL between rooms at the research site was 0.3 mGy for PA 0.3 mGy and 0.8 mGy for LAT chest projections.ConclusionThe LDRLs for chest X-rays established at this research site were lower than internationally reported DRLs. We recommend that LDRLs for routine chest X-rays should be repeated every 3 years, according to the ICRP.ContributionCurrently, no established or published DRL values prescribed by the Directorate of Radiation Control (DRC) are available in South Africa. The LDRLs established for routine chest X-ray examinations at this research site can serve as a guideline for the establishment of DRL values for other anatomical regions at the research site and other radiology departments in the country.

English

BACKGROUND Radiography is one of the important tools that dentists use to diagnose dental diseases in the oral cavity. Exposure of radiation is associated with hazardous effects on oral tissues. Doctors must have enough knowledge regarding the consequences of radiation exposure. The purpose of this study was to assess knowledge and perspective of dental practitioners towards dental radiography. METHODS This descriptive cross-sectional study was conducted in the month of November and December 2020, among dental practitioners who worked in the state of Sindh. All the participants were given the questionnaire survey link through social media including Facebook, WhatsApp, and Email and 24 closed ended questions were asked regarding dental radiography. A total of 247 dental practitioners responded and participated in the study. RESULTS Our study showed that only 3.60 % of general practitioners (GP) reported that they did not have radiographic unit. The participant’s knowledge regarding the technical details of equipment was limited. Majority of dental practitioners preferred long cone, more than 50 % specialist recommended F-speed of film. 34.53 % of general dentists and 37.73 % of specialists responded that they have digital radiography. More than 50 % of dental practitioners didn’t have license for x-ray equipment. Majority of them utilized paralleling technique for periapical x-ray. 63.40 % of GP and only 11.32 % of specialist held x-ray film with the fingers when taking x-ray. 30.41 % of GP and 24.52 % of specialist took the radiographs themselves, whereas 35.05 % had x-ray done by technician. Only 1.54 % of GP and 3.775 % of specialists gave the radiographic packing materials to specialized company in order to discard the waste materials. Only 6.70 % of GP and 11.32 % of specialists had the walls of the x-ray room covered with lead. CONCLUSIONS This study concluded that dental practitioners have little knowledge regarding dental radiography. KEY WORDS Knowledge, Perspective, Dental Practitioners, Dental Radiology

Assessment of radiation dose to pediatric patients during routine digital chest X-ray procedure in a government medical centre in Asaba, Nigeria

Objective: Radiation dose to pediatric patients have been widely reported, it is however necessary that imaging expert keep doses as low as possible to forestall stall long term cancer risk. This study is aimed at determining pediatric entrance surface dose (ESD), 75th percentile ESD, absorbed dose (D) and effective dose (E) for 0-15 years.&#x0D; Material and Methods: The study used a digital radiography (DR) unit with a grid system for each chest X-ray. The thermoluminescent dosimeter (TLD) used was encapsulated in transparent nylon, it was then attached to the patient skin (chest wall) and the second was placed directly at the posterior end of it.&#x0D; Results: The mean ESDs for the 4 age groups were as follows: 0- &lt; 1 (1.54±0.74mGy), 1- &lt; 5 (1.53±0.83mGy), 5- &lt; 10 (0.55±0.39mGy) and 10- ≤15 (1.30±0.57mGy), with an overall mean of 1.23mGy. The 75th percentile ESD for each age group above 10 patients (excluding 5- &lt; 10yrs) was 2.18, 2.19 and 1.75mGy respectively. The absorbed dose (D) ranged from 0.03-2.39mGy. The mean effective dose (E) for the 4 age groups was 0.18±0.03mSv. There was a good correlation between ESD and D (P = 0.001). A One-Way ANOVA shows that the field size and focus to film distance (FFD) affected the ESD and D (P &lt; 0.001) respectively. The risk of childhood cancer from a single radiograph was of the order of (1.54-23.4) ×10-6.&#x0D; Conclusion: The 75th percentile ESD, E and childhood risk of cancer was higher than most studies it was compared with. The study reveals that machine parameters such as the field size and FFD played a major role in dose increase. Protocol optimization is currently needed for pediatric patients in the studied facility.

Dosimetry of pediatric chest X-Ray examinations in Togo

ObjectiveTo assess the entrance surface dose (ESD) of pediatric chest X-ray examinations in order to establish a diagnostic reference levels (DRLs) in Togo. Materials and methodsThe study was carried out in 13 radiology departments within the 6 health regions of the country. This is a descriptive cross-sectional study relating to the dosimetric assessment of the skin of children aged from 0 to 15 years during chest X-ray examinations. The assessment was made by the empirical formula calculation of the entrance surface dose (ESD = 0.15 × (U/100)2 × Q × (1/FSD)2) and with the Internet Dose Calculation Module (MICADO) software online. Statistical assessment was performed using IBM SPSS 21 software. ResultsOur sample numbered 390 with a sex ratio of 1.3 and predominantly male. Examinations performed with the analog radiography units were more irradiating (0.14 mGy) than ones performed with digital detectors (0.12 mGy). The mean dose calculated with MICADO was low (Avg. = 0.12 mGy) compared to that calculated with the theoretical method (Avg. = 0.16 mGy). No significant relationship was found between the professional experience of operators and the entrance surface dose (r > −1 with p = 0.146 not significant). MICADO doses increased with age. The values of the diagnostic reference levels used for the antero-posterior or postero-anterior chest X-ray examinations for children aged 0–1 year; 1–5 years; 5–10 years and 10–15 years were respectively, 0.15 mGy; 0.14 mGy; 0.15 mGy and 0.17 mGy. ConclusionThe entrance surface dose varied greatly from one health facility to another for this same examination. In most of the different age groups of children, the diagnostic reference level was higher than that found in literature. Thus, effective measures must be put in place to optimize the doses delivered to children during chest X-ray examinations.