Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Moderate to large right - sided pleural effusion is again seen , not definitely changed given differences in technique compared to prior . The left lung is clear without effusion or consolidation . Cardiomediastinal silhouette can not be assessed . No acute osseous abnormalities identified .
    OUTPUT:
    
Moderate to large right pleural effusion not definitely changed since ___ .