Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable view of the chest was compared to previous exam from ___ . There is increased opacity at the left lung base which obscures the lateral costophrenic angle and lateral hemidiaphragm . This could be due to overlying soft tissues or potentially due to projection given significant rotation to the left ; however , underlying effusion is not completely excluded . Elsewhere , the lungs are clear of confluent consolidation or evidence of pulmonary vascular congestion . Cardiomediastinal silhouette is stable . Increased density projects in the lumbar vertebra suggestive of prior vertebroplasty . Osseous and soft tissue structures are otherwise unremarkable .
    OUTPUT:
    
No definite acute cardiopulmonary process .