Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Left - sided pleural effusion has slightly increased when compared to the prior examination . There is adjacent basal atelectasis . The lungs are otherwise clear . No interstitial pulmonary edema . The heart is not enlarged . Small right apical pneumothorax is stable in size .
    OUTPUT:
    
Slight interval increase in left pleural effusion . Small apical right pneumothorax is stable .