Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographs demonstrate clear lungs , without pleural effusion , or pneumothorax . The cardiac silhouette and mediastinal contours are normal though the aorta is tortuous . The pulmonary vasculature is normal . Thoracic kyphosis is unchanged , moderate in degree .
    OUTPUT:
    
No acute chest abnormality .