Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since ___ , new retrocardiac opacity representing possible pneumonia versus atelectasis versus pleural effusion . Small left pleural effusion is worsening . Right moderate pleural effusion is unchanged . Mild pulmonary vascular congestion is unchanged . Cardiac borders are unable to be assessed . There is no pneumothorax .
    OUTPUT:
    
Since ___ , new possible left lower lobe pneumonia or atelectasis . Worsening small left pleural effusion and unchanged right moderate pleural effusion .