Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac borders , left hemidiaphragm , and mediastinal contours are normal . There is interval elevation of the right hemidiaphragm with slight costophrenic angle blunting . Posteriorly , overlying the spine , is a wedge - shaped increased opacification .
    OUTPUT:
    
1 . Posterior opacification which could represent atelectasis although pneumonia is difficult to exclude in this clinical setting . 2 . Slight right costophrenic angle blunting likely represents pleural thickening versus small effusion .