Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . No findings are seen to suggest pneumothorax . There is persistent left base retrocardiac opacity which could be due to combination of effusion and atelectasis , underlying consolidation or even contusion in the setting of trauma not excluded . Left costophrenic angle is blunted , which may be small amount of pleural fluid . No focal consolidation is seen on the right . The cardiac silhouette is enlarged . The aorta is calcified and tortuous . Bilateral humeral heads are high riding with degenerative changes seen , which may be due to rotator cuff disease . Multilevel degenerative changes are seen along the spine , although the spine itself is not well evaluated due to technique .
    OUTPUT:
    
No definite evidence of pneumothorax . Left base retrocardiac opacity with obscuration of the diaphragm may be due to atelectasis and / or effusion . Underlying consolidation due to infection , aspiration or even contusion is not excluded . Blunted left costophrenic angle may be due to a trace pleural effusion .