Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A rounded left lower lobe retrocardiac opacity is seen again , essentially unchanged in size and morphology as compared to the most recent examination ; it is predominantly cystic / solid with small crescents of gas . A small left pleural effusion is unchanged . The remainder of the lungs are essentially clear without focal consolidation , pneumothorax , or pulmonary edema . The heart size is normal . Mediastinal and hilar contours are stable .
    OUTPUT:
    
1 . No radiographic evidence for acute cardiopulmonary process . 2 . Unchanged left lower lobe pulmonary sequestration and small left pleural effusion or pleural thickening .