This paper is to tell a number of tips used by the author that may be useful to improve the hair survival rate and the outcomes in operation using a Choi-hair transplanter.
What is most important but easily neglected in using a hair transplanter is the adjustment of the depth of transplanted hair. The author explains the characteristic of hair transplanter affecting the depth of transplanted hair, and operation know-how for producing the best effect in operation using such a hair transplanter.
Golden rules in using a hair transplanter
First, the depth of transplanted hair should be determined based on the length of each patient’s own hair follicle.
The length of needle is adjusted according to the depth of hair root to be transplanted in each patient. As in photograph M1a, M1b and M1c, the best length is that at which the hair follicle to be planted is visible slightly at the beginning part of the vevel from the frontal view.
Different from the length of the transplanter needle, the depth of the core should be the same regardless of patients. The optimal depth is that at which when the button of the hair transplanter is pressed its level is the same as or slightly lower than the end of the hair transplanter as in M2.
When a hair is loaded on the hair transplanter, the optimal depth is that at which the root of the hair is visible slightly in the vevel, and the hair follicle should not be visible from the side. See M1a and M1b.
With regard to the direction of transplantation, it seems helpful not only for cosmetic purpose but also for the survival rate to align the direction of transplanted hairs with the direction of existing hairs as in M4.
For the optimal position in which the transplanter needle enters the scalp, as in M5a, make the vevel point at the ceiling to make a small laceration on the scalp using the tip of the transplanter needle, and rotate the hair transplanter half way around while thrusting the needle in the desired direction and angle. At the final position, the transplanter needle vevel should point at the floor as in M5b.
It is also important when to press the button on the tip of the hair transplanter. It should be pressed at the point of time when the transplanter needle has been inserted completely into the scalp and then drawn out and the pressed scalp becomes even with the original surface of the scalp as in M6.
The following explains the reasons for observing each golden rule.
  • In case the needle of transplanter is too long, D1a
    The transplanted hair can be placed deeper than the reference depth, and the tip of the transplanter needle can damage the tissue underneath the hair papilla.
  • In case the needle of transplanter is too short, D1b
    The transplanted hair can be placed shallower than the reference depth and part of it may be exposed to the air or the hair follicle is crushed and makes the hair curly.
  • In case the core protrudes, D2a
    The root is pressed and crushed and a trauma can happen and the hair is highly likely to be curly.
  • In case the core is too deep, D2b
    The transplanted hair is placed shallower than the reference depth, and part of the root is exposed to the air.
  • In case the hair follicle is placed too deep, D3a
    The transplanted hair goes less deep than the reference depth.
  • In case the loaded follicle is exposed, D3b
    When the transplanter needle goes into the scalp, the root can be damaged.
If a hair is transplanted vertically, the depth of the transplanted hair becomes deeper than that of existing hair follicles as in D4a, and if it is transplanted at the acuter angle as in D4b its depth becomes shallower and may cause a low survival rate.
In order to minimize the contact area of the needle and the scalp and to make it easier to insert the needle, the vevel of the transplanter needle should point at the ceiling as in M5a. In addition, the vevel should point upward during insertion in order to minimize impact on the end of the hair follicle in the needle. Because force is applied downward during transplantation, the resisting force of the scalp goes upward. In this situation, if the vevel points downward, it can damage the end of the hair follicle. The reason that the direction of the vevel should turn downward at the last moment is to minimize damage on the tissue beneath the root of the transplanted hair by keeping the blade of the transplanter needle from entering deeper than the end of transplanted hair root as seen in D5a and D5b.
In case the scalp is soft or hair is transplanted on the face like eyebrow, if the button is pressed too early, the scalp extends after the transplanter needle is withdrawn and then the transplanted hair is buried completely in the scalp (D6a), and if the button is pressed too late the hair root is exposed (D6b).
Most of hospitals do not adjust depth, and only some hospitals adjust the depth of transplanted hairs using forceps after planting but this is only the second best. If incision is too deep it has already damaged the tissue beneath the root and if it is too shallow the adjustment of depth after the insertion of hair can crush the hair follicle. The consequence is a low survival rate and the curly growth of surviving hairs.
The author has used a hair transplanter for 7 years and improved the operation method by correcting its shortcomings, and based on these experiences, can say with confidence that operation using a hair transplanter, if done properly by the golden rules, can product a better result than any other operation method.