São Paulo State University Julio de Mesquita Filho, Medical School, Av. Prof. Mário Rubens Guimarães Montenegro - UNESP, Botucatu, Brazil , diana.pina@unesp.br
Abstract: (25 Views)
Background:Computed tomography (CT) is a crucial technique in clinical practice for diagnosing thoracic pathologies. However, the risk associated with ionizing radiation requires measures to reduce patient exposure. Materials and Methods: This study aims to optimize thoracic CT protocols on a multislice CT scanner, using both objective and subjective analyses of image quality to decrease radiation dose without compromising diagnostic accuracy. A 16-channel CT scanner with automatic tube current modulation (ATCM) was utilized, along with an analytical phantom for objective evaluation. Six protocols with different standard deviation values were selected, including three used in clinical routines and three additional ones for testing. Parameters such as spatial resolution, low contrast resolution, noise, and dosimetry were assessed. Subjective Image Quality evaluation was conducted through visual grading analysis (VGA). Results: Optimized protocols were selected based on acceptable image quality and dose results. Data were statistically analyzed, demonstrating that optimized protocols showed a significant reduction in radiation dose while maintaining adequate diagnostic quality. Conclusion: This study contributes to clinical practice by adhering to the ALARA (As Low As Reasonably Achievable) principles of dose reduction, ensuring accurate and safe diagnoses in thoracic CT examinations.