Predicting the Progression to Chronic Fibrosis of Lung Lesions Related to Covid-19 Infection From Chest CT Images

The main differences observed between SARSCoV-2 pneumonia and other epidemic viralpneumopathies (e.g., seasonal influenza) are the greater infectivity of SARSCoV-2, theclinical severity of the disease, particularly in young patients without co-morbidities,and the observation of radiological images related to significant parenchymal aggressionin a large number of patients.The lesions in the acute phase correspond essentially to bilateral ground glass opacitymore or less associated with condensations which would be markers of more severeinfections.The major scope of the lesions in the acute phase raises the question of whether or notthe scanning anomalies are completely resolved over time, and the possible impact on lungfunction. This risk of sequelae is very important to study given the large number ofpatients affected by SARSCoV-2, especially since these are often young patients whoappear to be "healthy".In the current context of the CoV-2 SARS pandemic, the improved quality and availabilityof diagnostic scanners provides a wealth of information on the semiology and progressionof lung disease with minimal exposure to ionizing radiation. A majority of hospitalizedpatients with SARSCoV-2 received a CT scan in the early phase of the disease. Indeed, theFrench Society of Radiology has recommended the performance of a CT scan withoutinjection in thin sections in case of suspicion or for confirmation of the diagnosis inpatients presenting initial or secondary clinical signs of severity and justifyinghospital management due to the initial lack of reagents for performing biological tests(RT-PCR) and the high sensitivity of the CT scan and its specificity in epidemic periods.The present study aims to study the kinetics of lung involvement in SARS CoV 2, to studythe predictive character of the chest CT scan performed at the patient's discharge on theexistence of radiological sequelae at 3 months but also at 1 year in order not tomisunderstand the constitution of late fibrosis after partial resolution of the CTimages. The investigatos will study the correlation between possible radiologicalabnormalities and the clinical presentation (patient symptoms and lung function). Therigorous follow-up of these patients will allow us to set up, if necessary, earlytreatment of the detected abnormalities (inhaled corticoids in case of bronchial orbronchiolar damage, study of the place of an anti-fibrosis treatment in case offibrosis,...).