Follicular Unit Excision with Black Patients and Kinky Hair

70 Follicular Unit Excision with Black Patients and Kinky Hair

Patrick Mwamba

Summary

Patients with curly or kinky hairs have the same curvature inside the scalp, from mild to extreme curl, known as a C-shaped hair follicle. This makes harvesting grafts, with minimal transection—with strip or follicular unit excision (FUE)—more difficult. To overcome this challenge during FUE harvesting, the physician needs to be especially careful. When performing FUE, the author uses a four-step FUE technique to successfully harvest grafts in patients with African hair characteristics. A semisharp punch or a motorized device with a flat FUE punch is the preferred tool.

Keywords: elliptical shape tight curls or coils moisturize C-shaped curl traction alopecia oxidative stress microinflammation four-step FUE technique flat FUE punch semisharp punch

Key Points

•Best results in African patients are with a semisharp or flat follicular unit excision (FUE) punch.

•Good visualization with high-power surgical loups is essential.

•Tumescence helps straighten the follicles and decrease transection.

70.1 Introduction

Performing follicular unit excision (FUE) hair transplantation on black patients can be difficult. There are a unique set of issues that increase the risk of poor results as well as complications. This chapter will discuss these issues as well as technical aspects of improving results when doing FUE in black patients.

70.2 Biology and Anatomy

The hair follicle has five key components. Starting from the bottom of the follicle, you find the dermal papillae, the matrix, outer root sheath, inner root sheath, and the hair shaft. The hair shaft is the only part of the hair follicle to exit the surface of the skin. The hair shaft is composed of three layers: the cuticle, cortex, and medulla. The cuticle, the outer layer that interlocks with the internal root sheath, forms the surface of the hair and shapes what is seen as hair emerges from the follicle. The middle layer, the cortex, comprises the bulk of the hair shaft and is what gives hair its strength and most of its pigment. It is composed of an organic protein called keratin. The center or core of the hair shaft is the medulla. It is often absent in fine and very fine hair.1

Racial variations are felt to be due to the asymmetric formation of the inner root sheath. If you look at the cross-section of the inner root sheath, the shape is elliptical in Africans, round in Asians, and oval in Caucasians. The shape of the follicle determines the shape of the hair shaft as it grows from the follicle. Since the hair shaft grows from the hair follicle, the diameter of the hair fiber will be the same as the diameter of the inside of the follicle.

In straight or wavy hair, hair follicles are more or less vertical to the surface of the scalp with a slight tilt. The angle of the hair follicle determines the natural flow or wave pattern of the hair. The follicle in straight or wavy hairs is typically round or oval.²

In hair that is tightly curled, the hair follicles grow from the scalp almost parallel to the surface of the scalp. The hair follicle that produces a tightly curled hair has a flattened, elliptical shape (Fig. 70.1).

Fig. 70.1 Diagram of ethnic differences in hair follicle shape. (a) East-Asian. (b) Caucasian. (c) African–American people.

The curve that we observe from the scalp is also often present inside or under the skin. The follicles are coiled and curved inside the skin. This occurs to variable degree from mild curl to extreme almost C-shaped curl. It sometimes is surprising to find that beneath the epidermis the hair straightens for 2 to 3 mm before curling again (Fig. 70.2).

Fig. 70.2 (a–c) Diagram of variations in follicle curl in Africans.

The follicles enable the hair strand to form tight curls or coils, which make it difficult for the oils, produced by the sebaceous gland, to travel down the hair shaft. The lack of oil causes the hair strands to become dry, which is the reason curly or kinky hair needs constant moisture.3

Whereas the shape of the follicle determines how curly or straight the hair is, the size of the follicle determines how thick the hair will be. Contrary to commonly held misperceptions, the caliber of the hair in blacks is lower than what is seen in other ethnicities. Hair shaft diameter in blacks averages 60 to 65 μm versus 70 to 75 μm in Caucasians and closer to 100 μm in Asians.

70.3 Causes of Hair Loss and Management

Androgenetic alopecia (male and female pattern baldness) is the major cause of hair loss in Africans as it is in the general population. Medical therapy followed by surgery is the classic way to treat this condition. There are other types of alopecias that are more common in blacks than in the general population including traction alopecia (TA), cicatricial alopecias, and iron and vitamin deficiencies.

70.3.1 Traction Alopecia

Hair styling (ponytails, braids, and other forms of mechanical traction) pulls the hairs, generating pain and inflammation around the follicle. Microinflammation and oxidative stress lead the passage of hair follicles from the anagen phase to the catagen phase. As this trauma is repeated over time, permanent hair loss and alopecia ensue.

Patients will notice at the beginning hair shedding in the frontal hairline, temple points, and temporal regions. These hairs will regrow. But over time, the patients will notice thinning and depigmentation of regrowing hairs and eventually they will be surprised by a permanent lack of hairs in that region (Fig. 70.3).