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BACKGROUND: Optimisation of average glandular dose (AGD) for two-dimensional (2D) mammography is important, as imaging using ionizing radiation has the probability to induce cancer resulting from stochastic effects. This study aims to observe the effects of kVp, anode/filter material, and exposure mode on the dose and image quality of 2D mammography. METHODS: This experimental study was conducted using full-field digital mammography. The entrance surface air kerma was determined using thermoluminescent dosimeter (TLD) 100H and ionization chamber (IC) on three types of Computerized Imaging Reference System (CIRS) phantom with 50/50, 30/70, and 20/80 breast glandularity, respectively, in the auto-time mode and auto-filter mode. The Euref protocol was used to calculate the AGD while the image quality was evaluated using contrast-to-noise ratio (CNR), figure of merit (FOM), and image quality figure (IQF). RESULTS: It is shown that AGD values in the auto-time mode did not decrease significantly with the increasing tube voltage of the silver filter (r = -0.187, P > 0.05) and rhodium filter (r = -0.131, P > 0.05) for all the phantoms. The general linear model showed that AGD for all phantoms had a significant effect between different exposure factors [F (6,12.3) = 4.48 and mode of exposure F (1,86) = 4.17, P < 0.05, respectively] but there is no significant difference between the different anode/filter combination [F (1,4) = 0.571]. CONCLUSION: In summary, the 28, 29, and 31 kVp are the optimum kVp for 50%, 30%, and 20% breast glandularity, respectively. Besides the auto-filter mode is suitable for 50%, 30%, and 20% breast glandularity because it is automatic, faster, and may avoid error done by the operator.
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Background: Most women are reluctant to undergo breast cancer screenings due to the pain and anxiety they experience. Sectional three-dimensional (3-D) breasttomosynthesis was introduced to improve cancer detection, but breast compression is still used for the acquisition of images. This study was conducted to investigate the effects of reduced compression force on pain, anxiety and image quality in digital breast tomosynthesis (DBT). Methods: A total of 130 women underwent screening mammography using convenience sampling with standard and reduced compression force at the breast clinic. A validated questionnaire of 20 items on the state anxiety level and a 4-point verbal rating scale on the pain level were conducted after the mammography. Craniocaudal (CC) and mediolateral oblique (MLO) projections were performed with standard compression, but only the CC view was performed with reduced compression. Two independent radiologists evaluated the images using image criteria scores (ICS) and the Breast Imaging-Reporting and Data System (BI-RADS). Results: Standard compression exhibited significantly increased scores for pain and anxiety levels compared with reduced compression (P < 0.001). Both radiologists scored the standard and reduced compression images as equal, with scores of 87.5% and 92.5% for ICS and BI-RADS scoring, respectively. Conclusions: Reduced compression force in DBT reduces anxiety and pain levels without compromising image quality.
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Intravenous urography (IVU) and unenhanced helical computed tomography (UHCT) urography are the two main procedures performed in the radiological investigation for urolithiasis (urinary stone). However, exposure to ionizing radiation is the main concern in both procedures. Therefore, a dose comparison study was conducted between IVU and UHCT urography procedures to determine the optimum exposure parameters in this study. An anthropomorphic whole body phantom was used following the exact procedure of UHCT urography and series of imaging for IVU with an administration of contrast media. Three different exposure parameters were used for IVU with 75 kVp, 80 kVp and 85 kVp while 100 kVp, 120 kVp and 140 kVp for UHCT urography respectively. As a result, the radiation doses for IVU were 1.40 mSv, 2.10 mSv and 2.79 mSv corresponding to 75 kVp, 80 kVp and 85 kVp. On the other hand, the radiation doses for UHCT urography were 0.76 mSv, 1.32 mSv and 1.82 mSv for 100 kVp, 120 kVp and 140 kVp, respectively. However the optimum image was obtained at 85 kVp for IVU and 120 kVp for UHCT urography. In conclusion, the doses obtained from IVU were consistently higher than UHCT urography but not signifi cantly different
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Interprofesion learning (IPL) occurs when students from two or more different professionals study with and learn about different professions. IPL is believed to enhance the collaboration level within the different profession after graduated. The objective of this research is to compare perception levels among the respondents coming from eleven different professions including Medical, Nursing, Dentistry, Pharmacy, Occupational Therapy, Dietetics, Audiology, Speech Science, Physiotherapy, Optometry and Diagnostic Imaging & Radiotherapy. Each respondent were selected randomly representing each year of study for each profession. They were required to fi ll up the survey form provided. 330 survey forms were returned instead of 367 distributed copies or 90% from overall surveys. Using one-way ANOVA analysis, all professions indicate same level of perception in knowledge subscale (p = 0.11), the practice of teamwork and cooperation (p = 0.23) and various methods to start the IPL (p = 0.61). However, for professional identity subscales and interprofession educational preparation the value was (p < 0.05). Post-hoc Turkey test, indicated Physiotherapy students had a higher average score (M = 4.35 ± 0.54) compared to Speech Science (M = 3.75 ± 0.59) in professional identity subscale whereas in students preparation subscale for interprofession education, only Physiotherapy students had higher score (M = 4.15 ± 0.82) in comparison to Diagnostic Imaging & Radiotherapy (M = 3.25 ± 0.83). Besides, independent T test showed the students were in favour of having IPL in early year of education with the average score (M = 3.53 ± 1.029) for year one and year two compared to year three to fi ve (M = 3.34 ± 1.089). The result form this research shows that the students have a positive perception towards IPL based on the average values not more than 3.0.
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Mammography is the most effective way to detect breast abnormality among women. However, mammography is believed to be able to cause radiation induced carcinogenesis. Therefore dose measurement is important to estimate the risk and to control the quality of the image. This study was conducted to compare the average glandular dose (AGD) acquired by the breast phantom with two different anode/filter combination which are tungsten/rhodium (W/Rh) and tungsten/argentum (W/Ag). CIRS 012A breast phantom was exposed in craniocaudal (CC) projection using Hologic Selenia digital mammography system. Entrance surface air kerma (ESAK) was measured using thermoluminescent dosimeter (TLD). AGD was obtained from basic calculation of ESAK with conversion factors according to Euref protocol. Independent t-test showed significant difference in the mean AGD. The AGD for W/Rh is higher as compared to the AGD for W/Ag (p = 0.002, 95% CI: 0.22, 0.53). In conclusion, the use of W/Ag contributes to dose reduction during mammography examination.
