Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are stable fibrotic changes involving both lungs with left apical scarring related to known prior tuberculosis exposure . There is a stable moderate layering right pleural effusion since ___ . There are no new focally occurring parenchymal opacities concerning for pneumonia . There is no evidence of pneumothorax . Cardiomediastinal and hilar contours are stable , with heart size within the upper limits of normal . Pulmonary vascularity is not increased .
    OUTPUT:
    
Stable layering moderate right pleural effusion since ___ .