Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP and lateral views of the chest demonstrate no acute intrathoracic process . The mediastinal , pleural and pulmonary structures are unremarkable . The cardiac silhouette is enlarged but unchanged . There is no pleural effusion or pneumothorax . Mild degenerative changes of the spine are again seen .
    OUTPUT:
    
No acute intrathoracic process .