Ruhollah Ghahramani-Asl - Department of Medical Physics and Radiological Sciences, Faculty of Paramedicine, Sabzevar University of Medical Sciences, Sabzevar, Iran, . Clinical Research Development Unit, Hospital Research Development Committee, Sabzevar University of Medical Scienc
Maryam Mousavi - Student Research Committee, Sabzevar University of Medical Sciences, Sabzevar, Iran
Zahra Javedanfard - Student Research Committee, Sabzevar University of Medical Sciences, Sabzevar, Iran

Background and purpose: To assess the feasibility of a treatment planning system in localizing, contouring, and targeting lung lesions along with an evaluation of volume indices of lung involvement in patients with COVID-۱۹ pneumonia.Methods: We evaluated ۱۰ patients with PCR-confirmed COVID-۱۹ pneumonia. The CT images were imported into the ISOgray® treatment planning system to anatomically define and contour the volumes of the pulmonary lesions, the lungs, and other nearby organs.Results: The ratio of lung lesion volume to lung volume in this study was ۰.۱۱ ± ۰.۱۳ (۱۱.۱۳%). The highest mean biosynthesis ratio of lung lesions was ۰.۳۶. The ratio of lesion volume in the left lung of patients with the highest volume of involvement, was ۰.۴۴, and the ratio of lesion volume in the right lung of these patients was ۰.۲۷ (approximately ۱.۵ times more in the left lung than the right lung). On average, CTDIvol and DLP for all patients studied in our study were ۱۱.۲۲ ± ۲.۴۷ mGy and ۳۵۴.۲۰ ± ۶۵.۱۱ mGy.cmConclusion: We reported the feasibility of using a treatment planning system in localizing COVID-۱۹ pulmonary lesions and its validity in the volumetric assessment of infected lung regions.

Low dose radiotherapy, treatment planning system, ۳ dimensional (۳D) conformal radiation therapy, COVID-۱۹, SARS-CoV-۲, acute respiratory distress syndrome (ARDS)