Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes remain low . In comparison to prior technically limited study , there is new density projecting over the left base though this appears to reflect crowding of the pulmonary vasculature in the setting of low lung volumes . There is no significant change from prior study including no convincing evidence of pneumonia . There is no effusion or pneumothorax . The lungs remain otherwise well aerated . Hilar and cardiomediastinal contours are unchanged , with mild cardiomegaly exaggerated by low lung volumes . There is no pulmonary vascular congestion or edema . Degenerative changes are seen in the thoracic spine . Surgical clips are seen in the right upper quadrant .
    OUTPUT:
    
No significant change from prior study including no convincing evidence of pneumonia . Retrocardiac opacity likely reflects crowding of the pulmonary vasculature , though if there is ongoing concern for infection , follow - up radigraphs could be obtained .