BL-06 (Cheng Guang) Light Guard

What does BL-06 Cheng Guang do?

BL-06 eliminates wind and clears heat, and it clears the head and benefits the eyes and nose. Its name, Light Guard, points at the eye function, and it is the most eye-oriented name in the scalp run.

• Eliminates wind and clears heat
• Clears the head and benefits the eyes and nose

The scalp run, stated once and referred to on each of its records. BL-03 through BL-09 are seven points in a line, and their recorded actions and indications overlap heavily — headache, blurred vision and nasal complaints recur across nearly all of them, and every one carries the same subcutaneous 0.3–0.5 inch insertion. That is a genuine feature of the source material. What separates these points is position along the line, and this library discloses the overlap rather than inventing distinctions.

BL-06 is the plainest member of the run. Comparing all seven records, it has the shortest indication list — three entries, against four to five for the others — and every one of those three appears on at least two of its neighbours. There is nothing recorded here that is unique to this point. Saying so is more useful than dressing the page up: BL-06 is a position on a line whose function is the line’s function.

On the name. “Cheng Guang” means Light Guard or Receiving Light — guang being light or brightness, the same character as in GB-37 Guang Ming (Bright Light), the Luo-Connecting point of the Gallbladder channel and a classical eye point. Both names use brightness as a figure for vision.

Source: Sacred Lotus sources & references (channel, action and translation records; the full BL-03 to BL-09 run and the GB-37 record queried and compared against our own data), cross-referenced against multiple online sources.

What is BL-06 Cheng Guang used for?

BL-06 is used for headache, blurred vision and nasal obstruction. Our own indication record is reproduced here in full — three entries, the shortest list in the scalp run.

• Headache
• Blurring of vision
• Nasal obstruction

All three are the run’s common stock, and this record says so. Counted across the seven records: headache appears at six of them, nasal obstruction at five, blurred vision at four. BL-06 records no indication that its neighbours do not also record. Where a point’s distinguishing feature is its position rather than its indication list, this library states that plainly instead of implying a specialism the source material does not support.

An honest note. Persistent or worsening blurred vision requires an eye examination, and sudden visual change is an emergency. Sudden severe headache warrants urgent medical assessment. This record documents classical use and should not delay either.

How it is combined. With BL-05 Wu Chu in front and BL-07 Tong Tian behind on the same line — the run is commonly used as a stretch rather than as single points, which is consistent with how little separates them. With DU-20 Bai Hui at the vertex. With BL-01, BL-02 and GB-37 for the eyes; with LI-20 Ying Xiang for the nose. All held here.

Source: Sacred Lotus sources & references (indication record; the indication lists of all seven scalp points counted and compared, and the BL-01, BL-02, BL-05, BL-07, DU-20, GB-37 and LI-20 records queried from our own data), cross-referenced against multiple online sources.

Where is BL-06 Cheng Guang located?

BL-06 is on the scalp 2.5 cun inside the hairline, on the 1.5-cun lateral line, one and a half cun behind BL-05.

• 2.5 cun inside the anterior hairline, 1.5 cun lateral to the midline
• 1.5 cun behind BL-05 Wu Chu; BL-07 Tong Tian lies 1.5 cun further back

The regular spacing starts here. BL-03 to BL-05 are close together near the hairline — BL-05 is only half a cun behind BL-04 — but from BL-05 onward the run settles into an even 1.5 cun between points: BL-05 to BL-06, BL-06 to BL-07, BL-07 to BL-08. Three equal steps across the top of the head. Knowing the spacing is uniform makes the chain easier to hold and easier to check.

The 1.5-cun lateral line is established at BL-04, whose record defines it proportionally as one third of the distance from DU-24 to ST-08 Tou Wei. Every point from BL-05 to BL-08 sits on that line.

The hairline problem. These points are measured from the anterior hairline, and a receded or asymmetrical hairline removes the reference; the classical solution takes anterior to posterior hairline as 12 cun and measures fractions of it. Our BL-03 record sets that out in full. At 2.5 cun in, BL-06 is far enough back that hairline error matters proportionally less than it does at BL-03.

Source: Sacred Lotus sources & references (location and translation records, retained unchanged; the BL-04, BL-05, BL-07 and BL-08 positions queried and their spacing compared against our own data).

• A Manual of Acupuncture (p. 260): 1.5 cun posterior to Wuchu BL-5, 2.5 cun within the anterior hairline and 1.5 cun lateral to the midline.
• Chinese Acupuncture and Moxibustion (p. 175): 2.5 cun directly above the midpoint of the anterior hairline and 1.5 cun lateral to the midline.

How is BL-06 Cheng Guang needled?

The standard texts record SUBCUTANEOUS insertion — the needle laid along under the skin — to roughly 0.3–0.5 inch. What follows is a neutral record of what the reference literature documents, not instruction for a reader.

• Angle and depth as recorded: subcutaneous (transverse), 0.3–0.5 inch — the same insertion recorded at every point in the BL-03 to BL-09 run.
• Moxibustion: our record does not state it as applicable at BL-06. Comparing the run, moxibustion is stated at BL-04, BL-05, BL-07 and BL-09 but not at BL-03, BL-06 or BL-08. Whether that reflects a genuine classical distinction or an omission in the source material cannot be determined from our data, and nothing is asserted either way.
• Regional anatomy: the epicranial aponeurosis lies beneath thin skin; branches of the supraorbital and superficial temporal vessels and nerves run in the region; the parietal bone lies directly beneath.

Why subcutaneous, and why that is the whole safety story. There is bone immediately under the scalp, so the transverse angle is the only insertion the anatomy permits rather than a stylistic choice. This is a low-hazard point in that specific sense: no cavity, no organ, no major vessel. The scalp is richly vascular and bleeds readily — a nuisance rather than a danger.

What is not claimed. No study measuring a safe depth at BL-06 could be located, and none is borrowed. The paediatric chest-CT study this library uses covers 23 points on the trunk and shoulder and does not include the scalp. No case report naming BL-06 was located.

Source: Sacred Lotus sources & references (needling record, retained unchanged, and the recorded insertions and moxibustion statements across all seven scalp points compared), cross-referenced against multiple online sources; regional anatomy from standard anatomical description.

Is there research on BL-06, and what should a reader know?

No trial isolates BL-06. Where the point appears it is one component of a headache or eye protocol, and a study that includes a point in a protocol is not evidence about that point.

A caution specific to the scalp. “Scalp acupuncture” is a distinct modern system with its own named zones and its own trial literature, and it is not the same thing as the classical Bladder-channel scalp points. Searches for evidence about points on the head return those trials, and they are not evidence about BL-06.

What this page can state with confidence, including what it cannot. BL-06 sits 2.5 cun inside the hairline on the 1.5-cun line, in the middle of an evenly spaced run. It has the shortest indication list of the seven scalp points, and records nothing its neighbours do not. It is one of the two points in the run whose record omits moxibustion. Those are the honest facts about it, and a page that claimed more would be padding.

A note on searching for it. “BL 6”, “UB 6” and “Chengguang” searches return protocol trials and unrelated material — Chengguang is a common personal name and appears in company names. Our library codes this channel BL- while some sources use UB-. 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 indication lists and moxibustion statements of all seven scalp points counted and compared against our own data).