Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are clear . Cardiomediastinal silhouette is within normal limits . There is no pneumomediastinum . There is however an air - fluid level in the region of the distal esophagus likely related to patient 's known achalasia . No acute osseous abnormalities . There is no free intraperitoneal air .
    OUTPUT:
    
Air - fluid level in the region of the distal esophagus compatible with patient 's known achalasia . No pneumomediastinum or free intraperitoneal air .