Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal images of the chest . There is a retrocardiac opacity , which could represent atelectasis but can not exclude pneumonia or aspiration in the right clinical setting . The lungs are otherwise clear . There is a small left pleural effusion . There is no right pleural effusion . There is no pneumothorax . The cardiomediastinal silhouette is top - normal size was otherwise unremarkable . The trachea is noted to be slightly deviated to the left at the level of the thyroid , suggestive of a right sided thyroid goiter . Bony destruction is noted in the head of the right humerus .
    OUTPUT:
    
Retrocardiac opacity , which could represent atelectasis but can not exclude a pneumonia or aspiration right clinical setting .