Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Since prior , there has been interval improvement of small irregular opacities at the lung bases , although they do persist . The cardiomediastinal silhouette is stable . There is no pleural effusion or pneumothorax . A posterior nodularity seen on lateral view , correlates to a Bochdalek hernia seen on chest CT .
    OUTPUT:
    
Improvement of irregular opacities at the lung bases , although they do persist . A chest CT can be obtained for further evaluation .