**4. Procedures of scalp acupuncture**

In practice of scalp acupuncture, sterile disposable acupuncture needles of the standard size of 0.20 × 25 mm or 0.22 × 25 mm are usually used. Acupuncture needles are obliquely inserted onto the selected acupoints with an angle of 15–30° after standard sterilization procedures. The needles should be inserted at a depth of 10 mm lying between aponeurosis layer and loose areolar connective tissue. Needles rest too deep or too shadow at the scalp structure will cause pain and diminished effect. After the insertion, mild stimulation to the needles is recommended. Needles can be swirled at time intervals. A standard session of scalp acupuncture treatment will last for at least an hour before the needles are carefully removed after the treatment.
