Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Stable thickening of the minor fissure . New retrocardiac opacity could simply be atelectasis , however in the appropriate clinical setting may represent pneumonia . No pneumothorax . Probable , minimal bilateral pleural effusions are mildly worsened . Hilar and cardiomediastinal contours are normal .
    OUTPUT:
    
New retrocardiac opacity could simply be atelectasis , however in the appropriate clinical setting may represent pneumonia .