Methods and Protocols
Quantitative Analysis Using CALIPER Software of the Vascular Component on Chest CT Scans in COVID-19 Pneumonia
By Roberta Pancani, Letizia Marconi, Francesco Tannura and 14 others.
Abstract
Background
Coronavirus Disease 19 (COVID-19)-associated pneumonia is characterized by a broad spectrum of severity. Endothelial injury is a prominent component of the disease, but the relative contribution of vessels of different sizes to this condition has not been extensively investigated. Quantitative computed tomography (CT) represents a potential tool to evaluate pulmonary vascular involvement.
Objectives
To investigate the relative contribution of vessels of different sizes in COVID-19-associated pneumonia of different severity using the Computer-Aided Lung Informatics for Pathology Evaluation and Rating (CALIPER) software.
Methods
We conducted a single-center retrospective study, including patients admitted to the Pisa University Hospital between March and April 2020 with COVID-19-associated pneumonia. We excluded patients with severe motion artifacts, inadequate CALIPER segmentation, or inconclusive etiologic confirmation. All CT scans were analyzed using CALIPER, which automatically segmented lung parenchyma and vascular-related structures (VRSs). VRS volumes were stratified by vessel cross-sectional area (<5 mm2, 5–10 mm2, 11–15 mm2, 16–20 mm2, and >20 mm2).