Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size and cardiomediastinal contours are stable . Lung volumes are low and apparent interstitial opacities in the lung bases likely represents crowding of vascular structures . No focal consolidation , pleural effusion , or pneumothorax .
    OUTPUT:
    
Apparent interstitial opacities in the lung bases , possibly due to crowding of bronchovascular structures related to low lung volumes . However , if clinical concern for pneumonia persists , PA and lateral views with greater inspiration effort are recommended .