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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: cervical,Image Quality,Radiation Dose,Digital Radiography Diagnostic Techniques and Procedures
- چکیده:
- چکیده انگلیسی: Introduction: In the Swimmer’s view, the C6 and C7 can be visualized as superimposed on the shoulders. This study aimed to explore the technique to demonstrate C1 to C7 in the lateral spine and improve the diagnostic value in that region.
Material and Methods: An experimental study was carried out using a RANDO phantom to obtain images of the lateral cervical spine. Twelve radiographs were taken using different kVps at different centering points. The image quality of the radiographs was evaluated by two radiographers using the modified image quality criteria score sheet adapted from the Commission of European Communities on image quality. A dose area product meter was utilized to estimate the entrance surface dose (ESD); however, CALDose_X5 Monte Carlo software was used to estimate the effective dose.
Results: The findings indicated that a higher centering point at 2 inches above the pinna of the ear can clearly visualize the lower cervical spine (C6/C7) and cervicothoracic junction (C7/T1). The results of the Kruskal-Wallis test revealed significant differences (p <0.05) in the image quality at different centering points. However, no significant differences were observed (p >0.05) in the ESD between different utilized centering points. The effective dose of the modified technique was reported to be lower, compared to that for the Swimmer’s view.
Conclusion: The modified lateral technique can be used to replace the Swimmer’s view to adequately demonstrate the lower cervical spine and cervicothoracic junction with a lower radiation dose while not harming the patient due to movement during positioning.- انتشار مقاله: 12-06-1398
- نویسندگان: Soo-Foon Moey,Najwa Athirah Hazri,Norfariha Che Mohamed
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: lumbar spine,Radiation dosage,Image Quality,Digital Radiography
- چکیده:
- چکیده انگلیسی: Introduction: Digital radiography possesses a wide dynamic range and has a major advantage in producing an acceptable image of diagnostic value even though overexposure occurs. Lumbar spine (LS) radiography is the most common examinations that gives high radiation dose to patients and accounts for the highest collective population dose of any conventional radiographic examinations. As such, this study was carried out to ascertain the impact of image quality and entrance surface dose (ESD) with different exposure settings in the anteroposterior (AP) and lateral LS.
Material and Methods: The torso of the PBU-50 phantom was exposed to medium and high kilovoltage peak (kVp). A total of 14 images for LS were obtained. Relative image quality was assessed using Leeds Test Objects TOR CDR whilst the ESD was ascertained using an optically stimulated luminescence dosimeter.
Results: The results of Friedman test indicated a significant difference in image quality when using medium and high kVp. Wilcoxon signed-rank test also reflected a significant difference in ESD between the use of medium and high kVp for both AP and lateral LS.
Conclusion: Significant differences in image quality and ESD were obtained using medium and high kVp with medium kVp resulting in high contrast but low contrast sensitivity and vice versa. The findings of the present study indicated that the recommended kVp for AP LS was from 75kVp to 81kVp whilst for lateral LS the recommended kVp was from 85kVp to 90kVp for an average adult patient.- انتشار مقاله: 13-06-1397
- نویسندگان: Hanis Aisyah Ramli,Soo-Foon Moey
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Chest,Image Quality,Radiation Dose,Digital Radiography
- چکیده:
- چکیده انگلیسی: Introduction: The introduction of digital radiography has led to a significant problem in terms of dose creep. To address this problem, manufacturers have established a set of exposure indicators (EI) as a feedback mechanism to safeguard against overexposure. The EI is the measure of incident exposure to the detector that is directly proportional to the signal-to-noise ratio and can be related to image quality. The aim of this study was to evaluate the influence of EI on image quality and radiation dose for the posterior anterior (PA) chest radiography.
Material and Methods: This study was conducted in three phases, namely pre-optimization, experimental, and post-optimization. A total of 60 patients that could fulfill the inclusion and exclusion criteria for the PA chest radiography were recruited. The radiographic technical parameters, dose area product, and EI were recorded. Radiographs were printed and evaluated by two recruited radiologists using the modified evaluation criteria established by the Commission of European Communities in 1996.
Results: Statistical analysis using Spearman’s Rho Correlation showed an insignificant relationship between EI and image quality for the PA chest radiography (p >0.05). Conversely, there was a significant relationship between EI and radiation dose (p <0.05).
Conclusion: TheEI can be used as an indirect measure of image quality and radiation dose. The EI does not directly determine image quality since the radiographic technique and parameters used can affect image quality. Although EI can be used as a measure of radiation dose, it cannot provide an accurate measurement of the radiation received by the patient.- انتشار مقاله: 01-05-1397
- نویسندگان: Soo-Foon Moey,Mohamad Asri Fatin Naimah
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Radiation dosage,Image Quality,Digital Radiography,cervical vertebrae
- چکیده:
- چکیده انگلیسی: Introduction: The purpose of this study is to investigate the effects of grid and non-grid techniques in the lateral cervical spine radiography on image quality and entrance surface dose (ESD). Although image quality and radiation doses have been studied by researchers, there is still a dearth of information on image quality and patient dose with different techniques.
Material and Methods: The radiographs of the lateral cervical spine were acquired by positioning the RANDO phantom abutting the erect bucky while using the grid and non-grid techniques. This study benefited from using a 24 cm x 30 cm Fuji standard cassette type imaging plate. A Leeds TOR test tool was utilized for relative comparison of image quality. The ESD of each examination was determined by using the optically stimulated luminescence dosimeter.
Results: The increased kilovoltage (kVp) resulted in the reduction of ESD whether moving grid, stationary grid, or non-grid techniques were utilized. Significant differences in terms of contrast sensitivity and spatial resolution were indicated when comparing the grid technique to that of the non-grid technique (i.e., χ2=8 and 5, 16 respectively, p<0.05"> ). The results also indicated significant differences in ESD when using the moving grid, stationary grid, and non-grid techniques (i.e., χ2=7.2, 16p<0.05"> ).
Conclusion: Significant differences in image quality and ESD were indicated when grid and non-grid techniques were used in the lateral cervical spine radiography. A non-grid with the highest appropriate kVp is recommended as the air gap acts as a grid, resulting in acceptable image quality with reduction in ESD.- انتشار مقاله: 04-05-1397
- نویسندگان: Soo-Foon Moey,Nurfatin Nabilah Mohd Ramlee
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Radiation dosage,Image Quality,Digital Radiography,Thoracic Radiography
- چکیده:
- چکیده انگلیسی: Introduction: The study was undertaken to evaluate the practice of chest radiography using different digital imaging systems and its influence on dose and image quality. Materials and Methods: The study was carried out in two hospitals from March 2016 to June 2016. Sixty ambulatory patients aged 21 to 60 years who were able to cooperate without difficulty and weighed between 60 to 80 kg were selected randomly. The active matrix flat panel imagers technology was employed in the direct radiography (DR) system for Hospital A, whilst Hospital B used the single read out computed radiography (CR) system. The dose area product (DAP) meter was utilized in measuring the entrance surface air kerma. The chest radiographs were evaluated by two radiologists. Results: The mean entrance surface doses (ESDs) for posteroanterior chest in Hospital A (0.098 mGy) was lower than that obtained in Hospital B (0.161 mGy). However, the ESDs at both centres were lower than the recommended value by the International Atomic Energy Agency (IAEA; 0.3 mGy). The quality of the images for chest radiography in both hospitals was adequate to make a diagnosis with ESDs and effective doses lower than those recommended by IAEA and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Conclusion: The study serves to highlight the practice of chest radiography with two different systems and its influence on image quality and dose. It can be concluded that there were significant differences in image quality and radiation dose for chest radiography practice using CR and DR.
- انتشار مقاله: 31-05-1396
- نویسندگان: Soo-Foon Moey,Zubir Ahmad Shazli,Inayatullah Shah Sayed
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Radiation Protection,X-ray,Digital Radiography,Radiation Monitoring
- چکیده:
- چکیده انگلیسی: Introduction
A fine balance of image quality and radiation dose can be achieved by optimization to minimize stochastic and deterministic effects. This study aimed in ensuring that images of acceptable quality for common radiographic examinations in digital imaging were produced without causing harmful effects.
Materials and Methods
The study was conducted in three phases. The pre-optimization involved ninety physically abled patients aged between 20 to 60 years and weighed between 60 and 80 kilograms for four common digital radiographic examinations. Kerma X_plus, DAP meter was utilized to measure the entrance surface dose (ESD) while effective dose (ED) was estimated using CALDose_X 5.0 Monte Carlo software. The second phase, an experimental study utilized an anthropomorphic phantom (PBU-50) and Leeds test object TOR CDR for relative comparison of image quality. For the optimization phase, the imaging parameters with acceptable image quality and lowest ESD from the experimental study was related to patient’s body thickness. Image quality were evaluated by two radiologists using the modified evaluation criteria score lists.
Results
Significant differences were found for image quality for all examinations. However significant difference for ESD were found for PA chest and AP abdomen only. The ESD for three of the examinations were lower than all published data. Additionally, the ESD and ED obtained for all examinations were lower than that recommended by radiation regulatory bodies.
Conclusion
Optimization of image quality and dose was achieved by utilizing an appropriate tube potential, calibrated automatic exposure control and additional filtration of 0.2mm copper.- انتشار مقاله: 30-04-1396
- نویسندگان: Soo-Foon Moey,Zubir Shazli
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Radiation Protection,Radiation dosage,Digital Radiography,Radiography Thoracic,Radiography Abdominal
- چکیده:
- چکیده انگلیسی: Introduction: In digital radiography, radiographers tend to increase exposure factors to acquire an acceptable image quality thereby increasing radiation dose to patients. Regarding this, the present study aimed to re-evaluate the exposure parameters and to ascertain the entrance surface dose (ESD) and effective dose (ED) of posterior-anterior (PA) chest, abdomen, and anterior-posterior (AP) lumbosacral spine radiography. Materials and Methods: This study was conducted on 180 physically able patients with age of 20-60 years and weight of 60-80 kg referred to Hospital Sultan Haji Ahmad Shah (HOSHAS) and Hospital Tengku Ampuan Afzan (HTAA).Image acquisition was performed using digital radiography. The ESD and ED were determined using CALDose_X 5.0 software. Results: The ESD and ED for PA chest were 0.098 mGy and 0.012 mSv in HOSHAS, while in HTAA were 0.161 mGy and 0.021 mSv respectively. Regarding the abdomen, the ESD and ED were 2.57 mGy and 0.311 mSv in HOSHAS and 2.16 mGy and 0.262 mSv in HTAA respectively. For AP lumbosacral spine, the ESD and ED for HOSHAS were 2.65 mGy and 0.222 mSv, while in HTAA were 2.357 mGy and 0.201 mSv respectively. Conclusion: The findings revealed the use of high kVp, automatic exposure control, correct focus image receptor distance, tight collimation and additional filter resulted in a lower ESD. The ESD and ED obtained in this study were comparable with those reported by other studies and lower than the values recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation in 2008.
- انتشار مقاله: 01-02-1396
- نویسندگان: Soo-Foon Moey,Zubir Shazli,Inayatullah Shah Sayed
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Medical Physics
- نوع مقاله: Journal Article
- کلمات کلیدی: Radiation Protection,Radiation dosage,Radiologic Phantom,Digital Radiography
- چکیده:
- چکیده انگلیسی: Introduction: Phantom studies facilitate the implementation of radiation dose surveillance as a function of radiographic technical parameters for minimizing patient radiation dose. The evidence of such investigations can then be used to evaluate technical parameters used in the radiographic procedures to reduce radiation dose without compromising the image quality.
Material and Methods: This experimental study was carried out using an anthropomorphic phantom and the Leeds test object. Computed radiographic system was utilized and the images were printed for objective evaluation. Dose-area-product (DAP) readings were obtained using a DAP meter for the technical parameters employed for the radiographic procedures.
Results: The use of 0.2 mm additional copper filtration resulted in the lowest radiation doses for all four radiographic procedures (i.e. posteroanterior chest, anteroposterior abdomen and lumbar sacral spine projections). The highest tube potential appropriate to the body part being imaged, patient size, image receptor response and required information resulted in the minimum radiation dose to the patient without compromising the image quality. The focus to film distance utilized for the radiographic procedure must be in accordance with the focus to grid distance specified by the manufacturer when using the bucky to eliminate grid “cut-off.”
Conclusion: The optimization of image quality and radiation dose can be accomplished by using a phantom and selecting the imaging parameters that yield an acceptable image quality with the lowest entrance surface dose while considering the adjustment for patient size.- انتشار مقاله: 03-12-1396
- نویسندگان: Soo-Foon Moey,Zubir Ahmad Shazli
- مشاهده
- جایگاه : پژوهشی
- مجله: Asian Pacific Journal of Cancer Prevention
- نوع مقاله: Journal Article
- کلمات کلیدی: Breast cancer,mammography,Health behavior
- چکیده:
- چکیده انگلیسی: Background: Breast cancer (BC) awareness is relatively poor among Malaysian women indicated by the presence
of BC at a late stage and the low rate of mammography screening. Only a few theoretically based studies have been
conducted on Malaysian women’s participation in mammography. Therefore, the objective of this study is to use health
belief model (HBM) and stage of change model (SCM) to determine the relationship between health beliefs on the
behavioral adoption of mammography amongst women in Kuantan, Pahang. Methods: Five hundred and twenty women
were randomly selected to complete the survey. Data were analyzed using multinomial logistic regression (MLR) to
ascertain the multivariate relationships between health beliefs and stage of mammography behavioral adoption. Results:
The MLR test indicates that there is no significant difference in perceived severity, benefits, motivator factors and cues
to action between participants in the action stage and the maintenance stage. However, significant differences existed
in perceived severity, susceptibility, motivator factors and self-efficacy between the pre-contemplation, relapse and
contemplation stage to that of the referenced (maintenance) stage of mammography adoption. Conclusion: Women in
the action stage are more likely to progress towards maintenance stage as they perceived breast cancer as a disease that
leads to death and that mammogram screening is beneficial in detecting the disease at an early stage. However, women
in the pre-contemplation, relapse and contemplation stage are found unlikely to move towards the maintenance stage
as they perceived their risk of getting breast cancer is low.- انتشار مقاله: 21-12-1397
- نویسندگان: Hanis Aisyah Ramli,Soo-Foon Moey,Aaina Mardhiah Abdul Mutalib
- مشاهده