Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lung volumes are low which causes crowding of the bronchovascular structures . Otherwise , the lungs are clear without focal opacity , pulmonary edema , pleural effusion or pneumothorax . The cardiac size is top normal . There is no free air beneath the right hemidiaphragm .
    OUTPUT:
    
No acute intrathoracic process .