Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Study is limited by patient positioning and patient 's left arm obscuring assessment of the left costophrenic angle . The heart size is normal . The aorta is tortuous and calcified . Mediastinal and hilar contours are unchanged . Minimal patchy opacities are seen within the left lung base , which could reflect atelectasis . Assessment for a left - sided pleural effusion is limited as the patient 's arm obscures this area . No right - sided focal consolidation is seen . There is no pneumothorax . Multilevel degenerative changes are noted throughout the thoracic spine .
    OUTPUT:
    
Limited exam . Left basilar patchy opacity likely reflecting atelectasis .