Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral chest radiograph demonstrates clear lungs bilaterally . Cardiomediastinal silhouette is within normal limits . Hilar contour is normal . There is no pleural effusion , pneumothorax , or evidence of pulmonary edema . There are degenerative changes of the thoracic spine .
    OUTPUT:
    
No acute intrathoracic abnormality .