Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to ___ chest x-ray , there is new patchy opacity at the right lung base , slight blunting of the right costophrenic angle , AND minimal , if any , atelectasis at the left lung base . No gross left effusion . No CHF . Cardiomediastinal silhouette unchanged . Biventricular pacemaker again noted . No pneumothorax detected .
    OUTPUT:
    
New or worsened right base patchy opacity . Differential diagnosis includes aspiration or an early pneumonic infiltrate . Atelectasis is in the differential , but considered less likely , as there also appears to be a small right effusion .