Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A single portable AP radiograph was obtained . The right hemidiaphragm is elevated . Retrocardiac opacity obscures the medial left hemidiaphragm . In addition there is an ill defined opacity along the lateral left lung base . There is no pneumothorax . There may be a small right pleural effusion . Cardiomegaly is moderate .
    OUTPUT:
    
1 . left retrocardiac and lateral lung base opacities may represent atelectasis or infection . 2 . Right hemidiaphragm elevation unchanged since ___