Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest were obtained . Streaky , linear left base opacity is most likely due to atelectasis . No pleural effusion or pneumothorax is seen . The cardiac and mediastinal silhouettes are stable . Slight prominence in the right paratracheal region is stable as compared to ___ and may represent vascular structures , prominent azygos , lower lung volumes .
    OUTPUT:
    
Relatively low lung volumes . Linear left base opacity is most consistent with atelectasis .