Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographs demonstrate a normal cardiomediastinal silhouette and fairly well - aerated lungs . There is mild linear atelectasis at the left lung base . The lungs are otherwise clear , without pleural effusion or pneumothorax . The visualized upper abdomen is unremarkable .
    OUTPUT:
    
No acute cardiopulmonary process .