Pulmonary Injury Resulting from Vaping or e-Cigarette Use: Imaging Appearances at Presentation and Follow-up.

Electronic cigarette or vaping product use-associated lung injury most frequently presents with an acute lung injury pattern at CT, manifesting as multifocal ground-glass opacity and/or consolidation, typically multifocal and multilobar, possibly with subpleural sparing. Areas of organization, manifesting as contracting consolidation, mild architectural distortion, intralobular lines, lobular distortion, and traction bronchiectasis may occur as the illness evolves. A CT appearance resembling hypersensitivity pneumonitis, reflecting the exquisitely bronchiolocentric micronodular lesions of organizing pneumonia and acute lung injury seen at histopathologic findings in these patients, may be encountered. Less common CT appearances include organizing pneumonia or acute eosinophilic pneumonia patterns, the latter consisting of multifocal opacity and smooth interlobular septal thickening, possibly with small effusions, but without clinical evidence of volume overload. Patients may present with pneumothorax or pneumomediastinum, or these conditions may develop during their illness course. Most patients improve clinically and at imaging on follow-up, particularly following exposure cessation and corticosteroid therapy, but the time course to improvement is variable and most likely related to the severity of the lung injury. Radiologists should be familiar with the imaging manifestations of vaping-associated pulmonary injury, and the possibility of this condition should be considered when the imaging findings reviewed in this article are encountered. © RSNA, 2020.