Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Lung volumes are low . Heart size is normal . Mediastinal and hilar contours are unchanged with a moderate - sized hiatal hernia re - demonstrated . The pulmonary vasculature is not engorged . A trace left pleural effusion is noted with blunting of the posterior costophrenic sulcus on the lateral view . Lungs are otherwise clear . Mild degenerative changes are noted in the thoracic spine .
    OUTPUT:
    
Trace left pleural effusion . No radiographic evidence for pneumonia . Moderate size hiatal hernia .