Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP frontal image of the chest . The lungs are well expanded . Mild interstitial abnormality of unclear etiology is seen . The lungs are otherwise clear . There is no pleural effusion or pneumothorax . Cardiomediastinal silhouette is unremarkable .
    OUTPUT:
    
Mild interstitial abnormality of unclear etiology . Conventional radiographs could be obtained for better assessment .