Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared with the prior radiograph , the left PICC has been retracted , now with tip in the upper SVC , possibly flipped into the azygos vein . The crescentic lucency overlying the right lung apex is probably the known small right apical pneumothorax last imaged on ___ . Postsurgical changes in the right lung including bronchial valves , pleural thickening , and pleural fluid , are unchanged . The previous large bulla in the superior segment of the left lower lobe was better characterized on this chest CT of ___ . The opacity at the level of the left hilum is unchanged . The heart is not enlarged .
    OUTPUT:
    
1 . The left PICC has been retracted , with tip in the region of the upper SVC , possibly flipped into the azygos vein . Lateral chest radiograph could be obtained for localization . 2 . Multiple postoperative right lung changes have not substantially changed since ___ . However , for more definitive characterization in this newly symptomatic patient , consider chest CT .