Avaliação de dose na região de interface entre tecido e meio de contraste em exames radiológicos contrastados

Abstract

Diagnostic radiology uses ionizing radiation as an essential tool for visualizing internal structures of the human body. In particular, contrast-enhanced examinations allow the evaluation of soft tissues, which, due to their low density, are poorly visible in conventional radiographs. Dosimetry, in this context, plays a fundamental role, as it allows for the measurement of the amount of radiation absorbed by tissues, contributing to the assessment of image quality and ensuring patient safety. In this context, the main objective of this study was to evaluate the radiation dose absorbed at the interface between tissue and contrast medium, comparing samples with iodinated contrast and barium sulfate to non-contrast-enhanced tissue. To guide the research, platforms such as Google Scholar and Scielo were used for the literature review, along with basic radiology references. The bibliographic research was based on fundamental concepts of radiology, contrast materials, contrast imaging exams, and dosimetry. The experimental methodology involved the creation of tissue-simulating phantoms using gelatin, glycerin, and the respective contrast agents, with measurements taken using a pencil-type ionization chamber. The tests were conducted at the Hospital de Clínicas of UFPR, under controlled exposure conditions, with variations in technical parameters and materials analyzed. The results showed that iodinated contrast exhibited greater radiation absorption, while barium sulfate showed a distinct attenuating behavior. The analyses indicated that dose distribution varies significantly according to the type of contrast and the presence of air layers, highlighting the importance of optimizing radiological protocols to ensure safety and diagnostic quality, in accordance with radiological protection principles.