On the head, 0.5 cun within the anterior hairline, 1.5 cun lateral to the anterior midline (GV-24), approximately one third of the distance between the midline and ST-8.
🧭 How to find it (practical)
Seated with the head supported, locate the point at the junction of the medial third and the middle third of the arched line connecting Shen Ting (GV-24) and Tou Wei (ST-8).
🔬 Anatomy
Frontalis muscle. Innervated by the frontal nerve.
💉 Needling
Transverse (subcutaneous) insertion of 0.5–0.8 cun.
📜 Etymology
Qu (曲), curved, bent; Chai (差), deviation. This meridian changes direction at Mei Chong (BL-3), making a curve at Qu Chai (BL-4).
