Reconstructive Surgery & Anaplastology

Dynamics of hair transplant on afro ethnic hair. Navigating the follicle curve and optimising hair follicle survival, growth and outcome on curved hair follicles

Celestine Gitau¹ and Shirley McDonald^{2* *}Correspondence: Shirley McDonald, Consultant Trichologist, The Hair and Scalp Clinic, UK, Email:

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INTRODUCTION

The enormous diversity of hair fibers found in all human populations is striking. The basic structure of human hair fibers is often the same. However, depending on ethnicity, the three-dimensional form of the complete fiber varies greatly. Tight curls, waves, and kinks are typical features of afro ethnic hair, which also grows nearly parallel to the scalp. Curly hairs also have curved follicles, which could make harvesting and transplanting these kinds of hair follicles incredibly challenging. Curved hair follicles require specialized maneuvering during the transplant procedure in order to extract complete and viable follicles, unlike straight hair follicles.

Graft survival after a hair transplant is essential for getting the bestlooking outcome. The growth and survival of follicular grafts following hair transplantation are influenced by a variety of factors. When performing hair transplant surgery, the shape of the hair follicle should be one of the most important considerations. The shape of the hair and the angulation of the hair follicle in the scalp both have an impact on how the hair grows [1,2].

Case Report

Critical hair follicle structures to preserve during hair transplant harvesting

Sebaceous glands (Figure 1)

Figure 1: Position of sebaceous glands within the hair follicle.

Outer root sheath (Figure 2)

Figure 2:Position of outer root sheath(ORS) within the hair follicle

Hair bulb (Figure 3)

Figure 3: Hair bulb an mid-segments of the hair follicle.

Dermal papilla (Figure 4)

Figure 4:Position of dermal papilla within the hair.

Factors in Hair Follicle Harvesting Technique

Afro ethnic hair growth

Direction of the hair fall guides on the direction of the hair follicle. The hair grows adjacent to the hair follicle, how acute the angle of the hair follicle to the hair is depends on how curly the hair is (Figure 5a-5d).

Figure 5: . a,b) Afro hair follicle curve, c,d) Illustration of adjacent growth of hair follicles and the hair shaft.

Punching technique

Consider the angulation of the punching machine. Too acute could transect the follicle. Too obtuse could traumatise follicle structures or even transect the follicle [3]. Stop the punch tip just before hitting the follicle curve or use a short punch (Figure 6).

Figure 6: Illustration on curved follicle punching.

Follicle extraction

Cosiderations while collecting a curved hair follicle after punching: amount of tissue still holding onto the hair follicle (Figure 7).

Figure 7: Illustration on extracting curved hair follicle after punching

Support the hair follicle gently with tissue forceps while pulling it from the skin. Rationale: Pulling without support could lead to leaving the lower part of the follicle under the skin(transection) [4,5]. The gentle pull ensures no trauma is caused by the tissue forceps holding the hair follicle (Figure 8 and 9)

Figure 8: Illustration on supporting curved hair follicle while extracting

Figure 9: a) Not Supporting, b) Supporting follicles while extracting, c) punch angulation.

Factors in hair follicle harvesting technique: Types of trauma

Transection

Follicle remains in the donor scalp tissue (Figure 10)

Figure 10: Transected hair follicle.

Pairing

Laceration or the ORS(outer root sheath by the punch tip) (Figure 11).

Figure 11: Follicle showing paring type of trauma.

The division of the hair follicle into fragments at either end. Resulting from an increase in axial force that causes the punch tip to rotate as a result of: supple skin, thick, long follicles elasticity of skin and punching with a blunt punch (Figure 12).

Figure 12: Follicle showing fracture trauma.

Dermal papila injury

The tissues of the outer root sheath, which contain the bulb and dermal papila, might be separated while pulling in cases of superficial punching depth. These tissues enable the perifollicular tissue and hair follicle to adhere to one another (Figure 13) [5].

Figure 13: Follicle showing dermal papilla injury

Considerations in follicle placement for wavy and curly hair follicles

1. Direction of hair growth-which direction is the hair growing towards?

2. Angle of the slit – slits are made in a diagonal direction.

3. Direction of the follicle curve inside the slit.

Placement of the hair follicle determines direction of hair growth (Figure 14)

Figure 14: Correct placement of curved follicles

Outcome of placing curved follicles in vertical slits

Placing curved hair follicles in verticle slits leads to hair growing in undefined direction. The hair lacks a definitife natural fall. It also could cause follicle trauma during planting (Figure 15).

Figure 15: Incorrect placement of curved follicles resulting in hair growing in undefined direction.

Discussion

Patients who have undergone follicular hair transplant using these techniques demonstrate higher graft survival rate which culminates to optimal results. For those whose hair transplant is done along the hairline these techniques gives the hairline a cosmetically acceptable hair fall and a natural appearance. This approach also show significant reduction in transection in afro ethnic hair.

Conclusion

The most ideal result from every procedure is a fantastic hair restoration surgery that aids in restoring the desirable cosmetic features . The direction that hair grows depends on where on the scalp it is. For a natural result, especially along the hairline and frontal area, proper angulation and direction of the transplanted hair are essential. Any graft even in the less conspiquous areas will not look natural if placed incorrectly. The first step to obtaining results you'll appreciate is having in-depth knowledge of the manoeuvres required to carry out a successful afro hair transplant. A well-done afro hair transplant requires meticulous preparation, in-depth expertise, and not to mention utmost artistry. It's crucial to keep in mind that patients who undergo surgery are worse off as a result. Hair t ransplant on afro ethnic hair is not only achievable but is a tremendously satisfying treatment when carried out skillfully, both for the physician and the patient.

References

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