Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral radiographs of the chest were acquired . A 4 - mm ovoid opacity projecting over the posterior aspect of the right fourth rib could be a small bone island , pulmonary nodule , or focus of pleural thickening . The lungs are otherwise clear . The heart size is normal . The mediastinal contours are normal . There is minimal pleural thickening at both apices . No pleural effusions are seen . There is no pneumothorax .
    OUTPUT:
    
1 . No acute cardiac or pulmonary process . 2 . 4 mm nodular opacity projecting over the anterior fourth right rib . Further evaluation with shallow oblique views could be performed .