Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral chest radiograph demonstrate bilateral streaky opacities at the bases , thought to reflect atelectasis , though of uncertain significance . No focal opacity convincing for pneumonia is detected . Heart size is within normal limits . A dilated or tortuous aorta is similar appearance to prior examinations dated ___ . No hilar abnormality is detected . No evidence of pulmonary edema , pleural effusion , or pneumothorax . Osseous structures are without acute abnormality .
    OUTPUT:
    
Streaky opacity at the right lower lobe is of uncertain significance , possibly atelectasis or alternatively interstitial abnormality .