Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Single portable AP chest radiograph demonstrates clear lungs . Heart size is top normal . No overt pulmonary edema . Mediastinal and hilar contours appear stable when compared to prior radiograph dated ___ . No large pleural effusion . Osseous structures are unremarkable .
    OUTPUT:
    
No acute intrathoracic abnormality .