Feasibility of Treatment Planning System in Localizing the COVID-19 Pneumonia Lesions and Evaluation of Volume Indices of Lung Involvement

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-19 pneumonia. Methods We evaluated 10 patients with PCR-confirmed COVID-19 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 0.11 ± 0.13 (11.13%). The highest mean biosynthesis ratio of lung lesions was 0.36. The ratio of lesion volume in the left lung of patients with the highest volume of involvement, was 0.44, and the ratio of lesion volume in the right lung of these patients was 0.27 (approximately 1.5 times more in the left lung than the right lung). On average, CTDIvol and DLP for all patients studied in our study were 11.22 ± 2.47 mGy and 354.20 ± 65.11 mGy.cm. Conclusion We reported the feasibility of using a treatment planning system in localizing COVID-19 pulmonary lesions and its validity in the volumetric assessment of infected lung regions.