Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Evaluation of the lung apices is limited by the head position . Within this limitation , lung volumes are low . There is basilar atelectasis . There is no large consolidation . Rounded opacity over the lower mediastinum suggests a hiatal hernia . There is no pneumothorax . Imaged portion of the cardiac silhouette is unremarkable . Mediastinal silhouette , hilar contours and pulmonary vasculature are normal . Osseous structures are normal .
    OUTPUT:
    
No acute intrathoracic abnormality . Probable hiatal hernia .