Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Small left pleural effusion with associated atelectasis , although underlying aspiration / pneumonia can not be entirely excluded . Lungs are otherwise clear . No pulmonary edema . Normal cardiomediastinal silhouette . No pneumothorax .
    OUTPUT:
    
Small left pleural effusion with associated atelectasis , alternatively aspiration or early pneumonia .