Optimization of dose and image quality in pediatrics chest digital radiography

Introduction: In this study, pediatric chest digital radiography (DR) is evaluated in response to the high volume of chest DR examinations and high radiosensitivity of children and young adults. The aim of the study is to optimize irradiation parameters in chest DR to have dose as low as reasonably achievable (ALARA) and simultaneously obtain improved or preserved image quality. Materials and methods: Homogeneous phantoms in terms of density, dimensions, and composition were constructed to produce equivalent chest phantoms with less than 5% error for the 5-10 and 1015-year-old age groups. The modulation transfer function (MTF), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured for both the reference and new conditions for the two age groups. Results: The results indicate that for the 5-10 year old age group, the optimized technique was 75 kVp and 6.3 mAs, in which the dose reduced 10% and the SNR and CNR increased by 0.4% and 6%, respectively, compared to the reference condition. For the 10-15-yearold age group, the 85 kVp and 5 mAs was close to the optimum condition, in which the dose reduced 37% and the SNR and CNR increased by 16% and 4%, respectively, compared to the reference condition. Conclusion: The introduced optimized conditions in this study are accompanied by lower dose and higher SNR and CNR; therefore, they Pour le groupe d'age 10-15 ans, 85 kVp et 5 mAs etait proche de la condition optimale, dans laquelle la dose a ete reduite de 37 % tandis que le SNR et CNR affichaient une augmentation respective de 16 % et 4 % par rapport a la condition de reference.