Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low which accentuates the size of the cardiac silhouette which is top normal . Mediastinal and hilar contours are unremarkable . Crowding of bronchovascular structures is demonstrated without overt pulmonary edema . Patchy opacities are noted in both lower lobes , likely atelectasis , and not substantially changed from the previous study . No focal consolidation , pleural effusion or pneumothorax is present .
    OUTPUT:
    
Low lung volumes with patchy opacities in the lung bases , likely atelectasis .