Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest were obtained . There are subtle areas of slightly increased opacity scattered bilaterally , which may be due to overlapping structures . However , given patient 's history , underlying ground - glass opacities and pulmonary infection are difficult to exclude . No lobar consolidation . No pleural effusion or pneumothorax . The cardiac and mediastinal silhouettes are stable and unremarkable .
    OUTPUT:
    
Subtle areas of small patchy opacity bilaterally , most likely relate to overlapping structures as these seem to be located in the region of the ribs . However , underlying ground - glass opacity and infectious process are not excluded . Subtle patchy left base opacity is stable as compared to ___ .