Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable frontal radiograph of the chest demonstrates a small left apical pneumothorax which is likely stable allowing for differences in technique . Opacification in the left upper lung likely relates to recent RFA . Stable appearance of the cardiomediastinal silhouette . No pleural effusion or right pneumothorax .
    OUTPUT:
    
Small left apical pneumothorax likely stable allowing for differences in technique with postprocedure changes in the left upper lung .