Relative Sparing of the Left Upper Zone on Chest Radiography in Severe COVID-19 Pneumonia

Abstract

The radiological findings of COVID-19 are well-described, including its evolution. In an earlier report of admission chest radiographs of patients with COVID-19, we anecdotally noted relative sparing of the left upper zone (LUZ). We subsequently aimed to describe the main chest radiograph findings in another cohort, focusing on zonal predominance. The admission chest radiographs of 111 patients with CO-VID-19 pneumonia requiring intensive care admission were reviewed by 2 thoracic radiologists and categorized according to the predominant pattern into either ground-glass opacities (GGOs), alveolar infiltrates and/or consolidation, or reticular and/or nodular infiltrates or an equal combination of both, and the extent of disease involvement of each of the zones using a modified Radiologic Assessment of Lung Edema (RALE) score. Parenchymal changes were detected in all. In total, 106 radiographs showed GGOs, alveolar infiltrates, and/or consolidation, and 5 had a combination of reticular/nodular infiltrates as well as GGOs, alveolar infiltrates, and/or consolidation. The LUZ had a significant lower grading score than the right upper zone: 1 versus 2 (p < 0.001). Likewise, the upper zones had a significant lower score than the mid and lower zones (p < 0.001). Our findings confirmed the relative sparing of the LUZ in severe COVID-19 pneumonia.