Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac , mediastinal , and hilar contours appear unchanged . There is new opacification in the right costophrenic sulcus which suggests atelectasis or perhaps loculated effusion which is new since ___ . Slight scarring in the right upper lung appears unchanged . Slight thickening along the right major fissure . Opacity obscuring the right posterior hemidiaphragm is probably due to atelectasis and perhaps a very small residual pleural effusion . Osteophytes are similar along the lower thoracic spine .
    OUTPUT:
    
New opacity obscuring the right costophrenic sulcus , suggesting atelectasis or perhaps loculated pleural fluid , but otherwise clear lungs ; an infectious process is difficult to exclude at the medial right lung base .