Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Allowing for differences in positioning , no definite change in the position of the left - sided pacemaker . The single pacemaker lead is unchanged in position , overlying the right ventricle . No pneumothorax detected . Inspiratory volumes are relatively low , more so on the per than on the prior film . Allowing for this , there is increased perihilar opacity and atelectasis at both lung bases . Possible vascular plethora . Increased retrocardiac density is again noted . Otherwise , no frank consolidation is identified . Possible trace fluid at the right cardiophrenic angle . No gross left - sided effusion . The cardiac silhouette is difficult to compare due to lower lung volumes , but is grossly similar . Incidental note is made of a partially imaged left shoulder hemiarthroplasty .
    OUTPUT:
    
1 . Pacemaker lead overlies the right ventricle , unchanged in position . Slight difference in the position of the pacemaker itself is noted , but may be accounted for by differences in patient positioning . 2 . Interval increase in bilateral perihilar opacities . This may be accentuated by low lung volumes resulting in increased atelectasis , but the possibility of increased perihilar vascular plethora / early CHF can not be excluded . 3 . Increased retrocardiac density , consistent with left lower lobe collapse and / or consolidation , unchanged . 4 . Possible small right - sided pleural effusion , new or more pronounced .