E1097. Lung Injury Resulting from Vaping or e-Cigarette Use: Imaging Appearances at Presentation and Follow-Up
  1. Prasad Panse; Mayo Clinic
  2. Butt Yasmeen; Mayo Clinic
  3. Maxwell Smith; Mayo Clinic
  4. Brandon Larsen; Mayo Clinic
  5. Henry Tazelaar; Mayo Clinic
  6. Howard Harvin; Southwest Medical Imaging
  7. Michael Gotway; Mayo Clinic
Lung injury resulting from vaping or e-cigarette use (EVALI) has emerged as a cause of respiratory illness that may preferentially affect younger individuals and can cause significant respiratory compromise. After the disorder was first recognized, awareness and legislation resulted in a decrease in the incidence of EVALI, but the condition has threatened reemergence in the setting of the SARS-CoV-2 pandemic.

Educational Goals / Teaching Points
To illustrate the chest imaging spectrum of EVALI in patients with histopathological evidence of this disorder, emphasizing commonly encountered chest CT patterns To demonstrate the imaging evolution and potential complications of EVALI in patients undergoing serial imaging To illustrate several atypical imaging presentations of EVALI.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
The most common imaging pattern encountered in EVALI at CT is ALI- multifocal ground-glass opacity, often with organizing consolidation- contracting consolidation, mild architectural distortion, intralobular lines, lobular distortion, and traction bronchiectasis- which may occur as the illness evolves. The second most commonly seen CT pattern of EVALI is a centrilobular nodular pattern, reflecting the exquisitely bronchiolocentric micronodular lesions of organizing pneumonia, resembling HP. Less commonly encountered CT manifestations of EVALI include a “pure” organizing pneumonia (OP) / chronic eosinophilic pneumonia (CEP)- like appearance consisting of peripheral, and often frankly subpleural, and peribronchial areas of consolidation, and an acute eosinophilic pneumonia (AEP) pattern, in which multifocal ground-glass opacity associated with smooth interlobular septal thickening, often accompanied by pleural effusions, are present in the setting of normal heart size. Subpleural sparing is fairly commonly encountered in EVALI patients (45% in this cohort). Pleural effusions are uncommon and when present are typically small. Lymphadenopathy may occur, but lymph nodes are only mildly enlarged and generally visible only at CT, without necrosis or hyperenhancement. CT findings atypical for EVALI include segmental consolidation and nodules, resembling bronchopneumonia, and cavitary lesions. Most patients with EVALI recover following exposure cessation and corticosteroid treatment. However, some patients may become severely ill and develop respiratory failure requiring mechanical ventilation, and deaths may occur. Among patients with more severe illness, CT abnormalities representing diffuse alveolar damage are more prevalent and complications associated with respiratory failure, including pneumothorax and pneumomediastinum, may be encountered.

EVALI most frequently presents with an ALI pattern at CT, often with areas of organization. A CT appearance resembling hypersensitivity pneumonitis is the second most commonly encountered pattern at CT. Radiologists should suspect EVALI when these CT patterns are encountered, particularly in younger individuals.