Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A retrocardiac opacity is present , best seen on the frontal view , and unchanged since the prior study . There is no pleural effusion or pneumothorax . The cardiomediastinal silhouette is within normal limits . There is no evidence of pulmonary edema .
    OUTPUT:
    
1 . No evidence of pneumonia or CHF . 2 . Retrocardiac opacity for which further evaluation with routine oblique views is recommended . Findings were discussed with Dr . ___ at 3 : 15 pm on ___ , via telephone .