Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is mildly enlarged with a left ventricular configuration . The patient is status post sternotomy . Fissures are mildly thickened , but without evidence for parenchymal edema . A focal opacity projects along the left lung base , new since the prior study , raising concern for pneumonia . The left hemidiaphragm remains mildly elevated . The bones are probably demineralized .
    OUTPUT:
    
Focal opacity along the medial left lung base , raising concern for pneumonia . If clinical findings suggesting an infectious process are not present , however , CT is suggested to exclude a mass ; otherwise chest radiographs are suggested within eight weeks in order to show resolution .