Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Opacity projecting over the right lung is worrisome for pneumonia , aspiration given clinical history of overdose , versus asymmetric pulmonary edema . Although could theoretically also be due to a layering pleural effusion if the patient is not fully upright . The left lung is clear . No pneumothorax is seen . Cardiac and mediastinal silhouettes are unremarkable .
    OUTPUT:
    
Right pulmonary opacity worrisome for aspiration given clinical history of overdose , versus asymmetric pulmonary edema . Given that the patient is upright , layering pleural effusion is less likely .