Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest provided . There is no focal consolidation , effusion , or pneumothorax . Cardiomegaly is moderate , as on prior . Imaged osseous structures are intact . No free air below the right hemidiaphragm is seen . Patchy density at the right base may represent scarring or atelectasis . Left perihilar density likely is a vascular structure .
    OUTPUT:
    
No acute intrathoracic process . Left perihilar density likely is a vascular structure , but appears more prominent compared to prior . Follow up is recommended after resolution of this acute episode .