Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is mildly enlarged with left ventricular configuration , and the thoracic aorta is tortuous , both without change since the prior study . . The pulmonary vasculature is normal . Lungs are clear except for a subtle patchy opacity in the right lung base posteriorly . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities .
    OUTPUT:
    
Subtle posterior right basilar opacity , potentially due to a small focus of pneumonia in the appropriate clinical setting . However , if the patient lacks infectious symptoms , other potential causes such as lung neoplasm should be considered .