SP-18 (Tian Xi) Celestial Ravine

What does SP-18 Tian Xi do?

SP-18 regulates and descends qi, and benefits the breasts and promotes lactation — the breast point of the Spleen’s chest cluster, sitting at nipple level.

• Regulates and descends qi — the chest-and-qi action shared across the Spleen chest points
• Benefits the breasts and promotes lactation — the action that sets SP-18 apart, and the reason for its position at the breast

Position and function match. SP-18 sits in the 4th intercostal space, 6 cun lateral — which is nipple level, right beside the breast. Its lactation-and-breast action follows directly from that placement: it is the Spleen chest point that lies at the breast, and the one used for insufficient milk and for breast disorders. The other three chest points (SP-17 below, SP-19 and SP-20 above) carry chest-and-qi actions without this breast emphasis.

On the name. “Tian Xi” means Celestial Ravine or Heavenly Stream — tian heaven or the upper body, xi a ravine or mountain stream. The reading usually offered ties the “stream” to the flow of milk the point promotes, high on the “heavenly” upper trunk. (Note the same xi, ravine, in LI-05 Yang Xi, a different point entirely.)

Source: Sacred Lotus sources & references (channel, action, location and translation records; the SP-17, SP-19 and SP-20 records queried against our own data), cross-referenced against multiple online sources.

What is SP-18 Tian Xi used for?

SP-18 is used for fullness and pain in the chest and side, cough, hiccup, mastitis, and insufficient lactation. Our own indication record is reproduced here in full.

• Fullness and pain in the chest and hypochondrium
• Cough
• Hiccup
• Mastitis (inflammation of the breast)
• Insufficient lactation (too little breast milk)

Chest-and-qi, plus the breast. The chest fullness, cough and hiccup are the qi-regulating-and-descending action; mastitis and insufficient lactation are the breast action, and the entries that distinguish SP-18 from its chest neighbours. It is the breast-and-milk point of the group.

An honest note. Mastitis needs medical assessment — it often requires antibiotics, and a breast abscess needs drainage; a red, hot, painful breast with fever should be seen promptly. Any new breast lump, skin change, or nipple change requires medical assessment to exclude cancer. Insufficient lactation is well supported by lactation specialists and medical care, which should be the first resort. Chest pain requires assessment to exclude cardiac causes. This record documents classical use only.

How it is combined. With SI-01 Shao Ze, the classical point for promoting lactation, and REN-17 Shan Zhong at the centre of the chest for the breasts and qi; with ST-18 Ru Gen below the breast. All held here.

Source: Sacred Lotus sources & references (indication and action records; the REN-17, SI-01 and ST-18 records queried from our own data), cross-referenced against multiple online sources.

Where is SP-18 Tian Xi located?

SP-18 is on the side of the chest at nipple level, in the fourth rib space, six cun out from the midline.

• In the 4th intercostal space (between the 4th and 5th ribs) — nipple level in the typical adult male chest
• 6 cun lateral to the anterior midline, beside the breast
• Between SP-17 one space below and SP-19 one space above, on the same 6-cun line

The nipple space is the landmark. The 4th intercostal space is the nipple level, and SP-18 sits in it, 6 cun lateral — out beside the breast toward the side of the chest. The nipple line (ST-17 sits on the nipple itself) is the reference; SP-18 lies further lateral in the same space. In women, where the nipple is not a reliable landmark, the rib space is counted directly.

On the name. “Tian Xi” — Celestial Ravine, the heavenly stream of milk, as noted above.

Source: Sacred Lotus sources & references (location and translation records, retained unchanged; the SP-17, SP-19 and ST-17 records queried from our own data).

• A Manual of Acupuncture (p. 202): On the lateral side of the chest, in the fourth intercostal space, 6 cun lateral to the midline.
• Chinese Acupuncture and Moxibustion (p. 162): In the 4th intercostal space, 6 cun lateral to the anterior midline.

How is SP-18 Tian Xi needled, and why only shallowly and obliquely?

Our own record states OBLIQUE insertion of 0.3–0.5 inch — deliberately shallow and angled — with moxibustion applicable. What follows is a neutral record of what the reference literature documents. It is not instruction, and this page does not teach technique.

• Angle and depth as recorded: oblique, 0.3–0.5 inch, skimming along the chest wall.
• Moxibustion: recorded as applicable.
• Regional anatomy: the point lies in the 4th intercostal space beside the breast; the intercostal nerve and vessels run under the rib above; immediately deep to the chest wall lie the pleura and the lung; breast tissue lies over the region.

Hazard, stated plainly. The serious risk at any chest point is pneumothorax — puncturing the lung. A perpendicular or deep needle here can reach the pleura; the recorded oblique, shallow technique exists to prevent it. Our record carries no arterial caution at SP-18, and it is not among the nine points that do — the governing hazard is the lung. This is a practitioner’s point, not one for self-treatment.

What is not claimed. No study measuring a safe depth at SP-18 could be located, and none is borrowed; the oblique-and-shallow rule stands in its place. No case report naming SP-18 was located.

Source: Sacred Lotus sources & references (needling record, retained unchanged including the oblique angle; the nine arterial cautions queried from our own data), cross-referenced against multiple online sources; regional anatomy from standard anatomical description.

Is there research on SP-18, and what should a reader know?

No trial isolates SP-18. Where the point appears it is one component of a protocol — often a lactation protocol — and a study that includes a point in a protocol is not evidence about that point.

What this page can state with confidence. SP-18 Tian Xi (“Celestial Ravine”) is the breast point of the Spleen’s chest cluster: it sits in the 4th intercostal space at nipple level, 6 cun lateral, and it benefits the breasts and promotes lactation — the action its neighbours lack and its position explains. Like all chest points it is needled obliquely and shallowly to avoid the lung beneath.

A safety note. Mastitis, a breast lump, and low milk supply are all matters for medical and lactation care first; this page records classical use and says so.

A note on searching for it. “SP 18”, “SP-18” and “Tianxi” searches return protocol trials and a large volume of unrelated material — “Tianxi” is a very common Chinese given and place name. Any claim attached to this point should be checked against what a study actually used.

Source: Sacred Lotus sources & references (action, indication and location records; the four Spleen chest points queried, against our own data).