In barium sulfate-based examinations of the stomach, the introduction of carbon dioxide is required for visualization of the:

The introduction of carbon dioxide in barium sulfate-based examinations is specifically used to enhance the visibility of the stomach mucosa. This is because carbon dioxide acts as a negative contrast agent, creating a distinction between the barium-filled areas and the surrounding tissues. By providing a clear contrast against the barium, it helps in delineating the mucosal lining, which is crucial for identifying any abnormalities or lesions.

The mucosa is the innermost lining of the stomach, where many important functions and pathologies occur. The enhanced visualization offered by carbon dioxide allows radiologists to better assess the condition of the mucosa, which is essential for accurate diagnosis and treatment planning. Thus, the use of carbon dioxide significantly improves the imaging of the stomach's internal structure, particularly the mucosal layer.