Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Ill - defined heterogeneous opacity in the right costophrenic angle may represent atelectasis or early pneumonia . Moderate cardiomegaly and aortic arch calcifications are unchanged . There is no pleural effusion , pulmonary edema , or pneumothorax .
    OUTPUT:
    
Heterogeneous opacity at right lung base may reflect aspiration or developing pneumonia . Short - term followup radiographs may be helpful .