Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since ___ , new opacity obscuring the left diaphragmatic sulcus concerning for pneumonia . Small left pleural effusion . Top - normal cardiac size . The lung volumes are normal . Normal hilar and mediastinal structures . no pulmonary edema .
    OUTPUT:
    
Since ___ , new possible left lower lobe pneumonia . Top normal heart size . Stable small left pleural effusion .