Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral views of the chest . Heart size and cardiomediastinal contours are normal . Retrocardiac left base opacity could represent a small Bochdalek hernia , but focal consolidation is not entirely excluded , although not definitely seen on frontal view . Costophrenic angles are indistinct , which may represent small pleural effusions . No lobar consolidation or pneumothorax .
    OUTPUT:
    
1 . Retrocardiac left base opacitiy could represent a small Bochdalek hernia , suggest confirmation with comparison with prior studies or CT to exclude an underlying consolidation . 2 . Costophrenic angles are indistinct and could represent small pleural effusions .