Comparasion of image quality and patient dose in chıldhood CT that is performed on different anatomıcal regıons wıth dıfferent tecnıcs at emergency service

Introduction and ObjectiveThe aim of this study is to determinate the image quality and image artifact degree and effective radiation doses of CT examinations in different age groups that performed at DEUTF ( Dokuz Eylul University Medical School Hospital ) emergency service unit. Also, to comparasion of these variants both in themselves and literature.Materials and MethodsThe pediatric age group patients whose CT examinations was performed at DEUTF ( Dokuz Eylul University Medical School Hospital ) emergency service unit between the dates of September 2008-September 2010 were included in the study. Pediatric brain, abdomen, thorax and cervical spine CT examinations were listed and four different list formed. A final single phase CT list of total 347 patients were retrospectively reviewed that was formed by randomly selection of every tenth patient from total of 3408 patients.Tube voltage peak (kVp), tube current product , mA, pitch, scan length (cm), CTDIw (mGy), DLP ( mGy x cm) parameters, patient age, patient gender, clinical indication information was obtained from the display screen.Patients were assigned arbitrarily to five age groups for the application of age-specific conversion coefficients. The patient ages was regrouped as three different group when at least, most, median and mean values of variable CT parameters were calculated to achieve a statistically significant findings.All the CT images were expected and were given scores between 1 and 4 according to the degree of image quality and artifacts by two radiogists , one of has 15 years of experience in the field of pediatric radiology and the other 4 years of experience. All CT parameter data entered into an Excel spreadsheet and effective doses were calculated according to the method of Huda by multiplying DLP data and age specified coefficents.All final data of CT examinations transferred to SPSS 16.0 software and lowest, highest, average values, value ranges and standard deviations were calculated. Their correlation was evaluated by "Kendall 's" method.The harmony between two radiologists was assessed by Kappa test.ResultsThe mean effective dose that exposed in brain CT examinations was found 3 mSv in zero age group, 2.8 mSv in one age group, 2.05 mSv in five age group, 2.4 mSv in 10 age group and 1.8 mSv in 15 age group.The mean effective dose that exposed in cervical spine CT examinations was found 1.5 mSv in zero age group, 3.3 mSv in one age group, 3.6 mSv in five age group, 6.6 mSv in 10 age group and 4.2 mSv in 15 age group.The mean effective dose that exposed in thorax CT examinations was found 5.02 mSv in one age group, 4.9 mSv in five age group, 5.16 mSv in 10 age group and 5.35 mSv in 15 age group. In thorax CT list there was no zero age group patient.The mean effective dose that exposed in abdominal/pelvic CT examinations was found 9.6 mSv in five age group, 13.3 mSv in 10 age group and 11 mSv in 15 age group. In abdominal/pelvic CT list there was no zero and one age group patient.ConclusionDLP method is commonly used for the calculation of effective dose, although its accuracy on pediatric patient group is uncertain. However, without the need to consultation on the medical physicist, it is so practical to implement easily. In pediatric age group patients, structures are often smaller as well. These factors can translate to a need for higher image quality, hence, higher radiation doses. CT examinations of pediatric age group forms an important part of radiological dose caused by exposure. So, some rules and recommendations should be considered by radiology workers. In the end, the radiologist must accept the responsibility for both study quality and patient safety. If the study is nondiagnostic, then one of the two cornerstones of imaging is absent: sufficient diagnostic quality has not been obtained. If too much dose is used, then the second cornerstone is not present and the welfare of the patient is not protected. It is when both of these cornerstones are present that we provide trueexpertise.