Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral radiographs of the chest demonstrate well expanded and clear lungs . Incidental note is made of a pneumatocele at the left lung base . The cardiomediastinal and hilar contours are unremarkable . There is no pneumothorax , pleural effusion , or consolidation . There is pes excavatum .
    OUTPUT:
    
1 . No pneumonia . 2 . Pneumatocele present at the left lung base . Recommend shallow oblique radiographs for additional evaluation . 3 . This radiograph does not confirm nor exclude the presence of a pulmonary embolism , and CT of the chest would be appropriate if suspicion for pulmonary embolism is high .