International Journal of New Technology and Research (IJNTR) ISSN:2454-4116, Volume-2, Issue-3, March 2016 Pages 09-14 9 www.ijntr.org Abstract—Chest and abdomen radiographs are the most common examinations in paediatric radiology. It is important to ensure that patient radiation dose is kept to low level without image quality degradation. In this work, the effective dose, risk and image quality were assessed in chest and abdomen radiography. Eighty children (40 boys, 40 girls) participated in the study and they were categorized in four age groups, according to their anatomical characteristics. The dose and risk were estimated utilizing the PCXMC 2.0 code. The image quality was assessed by two radiologists based on image features provided by the CEC guidelines. The mean effective dose value was 13 μSv and 34.6 μSv for chest and abdomen, respectively. The risk was slightly higher in the case of 1 y age group. Image quality values were similar for all age groups, with a slight increase in chest radiographs compared to abdomen radiographs. Improved image quality values were obtained for the processed images, for both chest and abdomen radiographs. Index Terms— Abdomen Radiography, Chest Radiography, Radiation Dose, Image Quality I. INTRODUCTION Chest and abdomen radiographs are the most common examinations in paediatric radiology. The main advantages of chest and abdomen radiographs are the low cost and the high speed of acquisition and diagnosis. However, it is important to ensure that patient radiation dose is kept to low level, due to the increased children radiosensitivity and longer life expectancy [1] without degradation of the image quality (IQ). Many studies have been reported dealing with patient dose, image quality or both, in paediatric radiography [2-6]. These studies refer either to film based systems, or computed radiography (CR) systems and highlight the fact that the effective dose (ED) and consequently the associated risk depend on the patient size [7]. A. P. Ladia, Department of Medical Physics, School of Medicine, University of Patras, Patras, 26504, Greece, S. G. Skiadopoulos, Department of Medical Physics, School of Medicine, University of Patras, Patras, 26504, Greece, C. P. Kalogeropoulou, Department of Radiology, School of Medicine, University of Patras, Patras, 26504, Greece, P. E. Zampakis, Department of Radiology, School of Medicine, University of Patras, Patras, 26504, Greece, G. G. Dimitriou, Department of Paediatric, School of Medicine, University of Patras, Patras, 26504, Greece, G. S. Panayiotakis Department of Medical Physics, School of Medicine, University of Patras, Patras, 26504, Greece In this study, the ED, risk and IQ for four age groups of children undertaken chest or abdomen radiographic examination, using a CR system, were evaluated, utilizing a Monte Carlo based code, the PCXMC 2.0. II. PATIENTS AND METHODS A. Patient Data Eighty children (40 boys, 40 girls) who underwent chest or abdomen examinations participated in this study. The chest radiographs were posterior- anterior and the abdomen radiographs anterior- posterior projection. All examinations were performed using the GE Model MS 18S radiology unit with tube filtration 3.5 mm Al at 80 kVp, installed in the Karamandaneio Children Hospital of Patras. The children were categorized into four age groups (1, 5, 10, 15 y), according to their anatomical (weight and height) characteristics (see Table 1). Patient data (sex, age, weight, height, body mass index (BMI)) and exposure parameters (tube voltage, tube load, Focus Skin Distance (FSD)) were collected for both examinations (see Table 2 and 3). B. Entrance Surface Dose The most widespread indicator used in dose calculation is the Entrance Surface Dose (ESD). The x-ray tube output and the exposure parameters (tube voltage, tube load) were utilized to calculate the ESD values, using the equation [8]: (1) where T.O. is the output of the x- ray tube (in mGy/mAs) at 80 kVp at a distance of 1 m normalized, tube load is the product of the tube current (in mA) and exposure time (in seconds), FSD is the focus skin distance (in cm) and BSF is the back scatter factor. The value of BSF used was 1.3 [9]. The values resulted from equation 1 were compared with the corresponding ESD values, as estimated by the PCXMC 2.0 code, for each patient. Radiation Dose and Image Quality Evaluation in Paediatric Radiography A.P. Ladia, S.G. Skiadopoulos, C.P. Kalogeropoulou, P.E. Zampakis, G.G. Dimitriou ,G.S. Panayiotakis