New focal irregular opacity at the left lung base, measuring 1.4 cm, which may represent pleural thickening or parenchymal scarring. Less likely to be an overlying rib or callus formation. Atelectasis, scarring, or aspiration cannot be excluded. Further evaluation with a repeat PA and lateral chest radiograph in full inspiration is recommended.
Pleural scarring (Uncertain) Atelectasis (Uncertain) Aspiration (Uncertain)