Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A portable frontal chest radiograph redemonstrates irregular aeration of the left lung , particularly the lingula and lower lobe , which is no worse than on prior radiograph . The right lung and cardiomediastinal silhouette are unchanged . There is a residual small left pleural effusion . There is no pneumothorax .
    OUTPUT:
    
1 . No pneumothorax . 2 . Irregular aeration of the left lung ( particularly the lingula and left lower lobe ) is no worse than before . 3 . Residual small left pleural effusion .