Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: As compared to the most recent prior study , the chronic pleural and parenchymal changes at the bilateral lower lung zones on the right greater than the left appear unchanged . There is increased opacification at the left lung base from ___ . The cardiomediastinal contours are stable . The pulmonary vasculature is not engorged and there is no overt pulmonary edema . Small pleural effusions are likely present .
    OUTPUT:
    
Increased left basilar opacification may represent atelectasis ; however , focal consolidation can not be excluded in the appropriate clinical context .