Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Low lung volumes are noted . There is persistent pulmonary edema which has slightly improved when compared to prior . There is no pleural effusion or focal consolidation . The cardiomediastinal silhouette is stable in configuration given lower lung volumes . No acute osseous abnormalities .
    OUTPUT:
    
Pulmonary edema which has slightly improved since ___ .