Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient 's condition required examination in sitting position using AP frontal and left lateral views . There is status post sternotomy and evidence of bypass surgery with multiple metallic surgical clips in the anterior left - sided mediastinum and ring - shaped graft markers at the anterior wall of the ascending aorta . Heart size can not be assessed because of right - sided basal pulmonary densities concealing the cardiac contours . Marked cardiomegaly is unlikely . The pulmonary vasculature is not congested . There is mild blunting of the left lateral and posterior pleural sinus , indicating small amount of pleural effusions on that side . Lungs are clear in the left hemithorax . On the right lung base , a diffuse density is observed obscuring completely the contour of the right - sided hemidiaphragm . This finding is identified as lobe collapse and appears to be unchanged . Comparison with a frontal chest examination of ___ , demonstrates the findings prior to the collapse and showed normal diaphragmatic contours and well ventilated right lower lobe and middle lobe structures with absence of any pleural effusion . Status post bypass surgery existed already at that time .
    OUTPUT:
    
Persistent right lung base findings consistent with right middle lobe and lower lobe collapse . Additional thickening of lateral pleural space on right side , indicative of additional pleural effusion . Cause of the collapse is not clear on the plain chest examinations . Unless airway exploration is performed to exclude central airway obstruction airway , a chest CT is recommended to diagnose the cause of the major lung collapse .