Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Comparison is made to prior study from ___ . Lung fields are grossly clear without pulmonary edema , focal consolidation , or pleural effusions . Heart size is within normal limits and improved when compared to the prior study where there was low lung volume . There are also degenerative changes of the lumbar spine .
    OUTPUT:
    
Improved aeration without signs for acute cardiopulmonary process .