| Institution: | 1. Division of Radiology, Department of Medical Technology, Kyushu University Hospital, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan;2. Department of Radiological Technology, Faculty of Health Sciences, Kobe Tokiwa University, 2-6-2 Otanicho, Nagata-ku, Kobe 653-0838, Japan;1. Imperial College Healthcare NHS Trust, Hammersmith Hospital, Radiology Department, UK;2. King''s College London, Florence Nightingale Faculty of Nursing, Midwifery & Palliative Care, UK;3. Bedfordshire Hospitals NHS Foundation Trust, Luton & Dunstable University Hospital, Radiology Department, UK;4. Institute of Medical Imaging and Visualisation, Department of Medical Science & Public Health, Faculty of Health & Social Sciences, Bournemouth University, UK;1. Tameside & Glossop Integrated Care NHS Foundation Trust, United Kingdom;2. School of Health and Society Allerton Building, University of Salford, Manchester M5 4WT, United Kingdom;1. Sengkang General Hospital, 110 Sengkang East Way, Singapore 544886;2. Singapore General Hospital, Outram Road Singapore, Singapore 169608;3. National Cancer Centre Singapore, 11 Hospital Crescent, Singapore 169610;4. Kandang Kerbau Hospital, 100 Bukit Timah Road, Singapore 229899;5. Changi General Hospital, 2 Simei Street 3, Singapore 529889;6. National Heart Centre Singapore, 5 Hospital Drive, Singapore 169609;7. National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308433;1. Department of Radiography, School of Biomedical & Allied Health Sciences, University of Ghana, Ghana;2. School of Nursing, University of Ghana, Ghana;1. Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany;2. Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany |
| Abstract: | IntroductionDual-energy subtraction (DES) imaging can obtain chest radiographs with high contrast between nodules and healthy lung tissue, and evaluating of chest radiography and evaluating exposure conditions is crucial to obtain a high-quality diagnostic image. This study aimed to investigate the effect of the dose allocation ratio of entrance surface dose (ESD) between high- and low-energy projection in low-contrast resolution of soft-tissue images for two-shot DES imaging in digital radiography using a contrast-detail phantom (CD phantom).MethodsA custom-made phantom mimicking a human chest that combined a CD phantom, polymethylmethacrylate square plate, and an aluminum plate (1–3 mm) was used. The tube voltage was 120 kVp (high-energy) and 60 kVp (low-energy). The ESD was changed from 0.1 to 0.5 mGy in 0.1 mGy increments. Dose allocation ratio of ESD between 120 kVp and 60 kVp projection was set at 1:1, 1:2, 1:3, and 2:1. Inverse image quality figure (IQFinv) was calculated from the custom-made phantom images.ResultsWhen the total ESD and aluminum thickness were constant, no significant difference in IQFinv was observed under most conditions of varied dose allocation ratio. Similarly, when the total ESD and the dose allocation ratio were constant, there was no significant difference in IQFinv based on the aluminum plate thickness.ConclusionUsing IQFinv to evaluate the quality of the two-shot DES image suggested that dose allocation ratio did not have a significant effect on low-contrast resolution of soft-tissue images.Implications for practiceThe present results provide useful information for determining exposure conditions for two-shot DES imaging. |
