Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided . Mild subsegmental left basal atelectasis noted . Otherwise lungs appear clear . There is no convincing sign of pneumonia or edema . No large effusion or pneumothorax is seen . The cardiomediastinal silhouette is normal . Imaged osseous structures are intact . No free air below the right hemidiaphragm is seen .
    OUTPUT:
    
No acute intrathoracic process .