Which point is 0.4 cun lateral to the corner of the mouth?

• A. St 4
• B. St 5
• C. St 7
• D. Li 20

Answer: (A)

The key idea here is precise facial point localization using a small, specific horizontal distance from the mouth corner. The point that lies about 0.4 cun to the side of the corner of the mouth, on the Stomach channel and at the same level as the mouth, is ST4 (Dicang). This location is a classic landmark for a point that sits right beside the mouth, not aligned with the nose or jawline.

Li20 sits in the nasolabial groove at the side of the nose, ST7 is down along the cheekbone near the jaw, and ST5 sits higher and more toward the cheek near the masseter. So the one located 0.4 cun lateral to the mouth corner is ST4.