Late Breaking Abstract - Chest magnetic resonance as an alternative imaging examination for follow-up of patients with cystic fibrosis

<bold>Study Objective:</bold> To assess magnetic resonance imaging as a substitute for chest tomography for assessing structural lung damage in follow-up of patients with cystic fibrosis at a reference center. <bold>Materials and Methods:</bold> The images were retrieved from the electronic medical records of patients treated at the multidisciplinary Cystic Fibrosis outpatient clinic at the Pequeno Príncipe Hospital in Curitiba between January 2019 and December 2021. The main structural changes in the lung parenchyma present in each exam were extracted and classified using standard scoring (Bhalla – specific for tomography and Einchinger for Magnetic Resonance Imaging). <bold>Results:</bold> The mean age of the patients included was 11.14 years. Bronchiectasis was present in 71.4% of CT scans, and also visualized by MRI. Mucoid impaction in CT scans and mucus plug in MRI (considered similar) were visualized by both exams (N=17 / 81%). Abscess/sacculations were observed in 3 patients (66.7% present only in MRI) not confirmed by chest CT scans. <bold>Conclusion:</bold> We conclude that chest MRI detected the most prevalent structural abnormalities in the current examination used in CF follow-up, i.e. tomography: bronchiectasis and mucus plug with overall prevalence of 95.2% and 81%, respectively. The results support the introduction of Magnetic Resonance Imaging as a test for monitoring and detecting the main changes present in CF without exposure to radiation; however, more intervention trials are needed in order to assess its diagnostic potential.