Standardization of SMP Procedure and Its Impact On Outcome

Cosmetic deformities can result from various types of alopecia or even post hair transplantation procedures. Patients with such deformities seek aesthetically appealing longer-lasting options. Scalp concealers are commonly used by men and women to camouflage these deformities. Scalp micropigmentation (SMP) is one of the concealers recently gaining popularity.

SMP is a novel technique wherein microdot tattoos are placed in a stippling pattern to mimic hair follicles that are cut close to the scalp and various variables affecting its outcome were evaluated.

Methods:

Forty-five subjects were recruited for the study. The various factors affecting outcome of SMP—angle of needle against the scalp, depth of needle into the scalp, time of the needle contact in scalp, speed of the rotor, resistance of scalp, color of pigment, viscosity of dye, needle number, needle thickness, and pattern of dot placement—were systematically studied in 15 patients through clinical photographs and trichoscopy.

Ideal depth of pigment deposition was assessed through histopathological examination. After using these optimum variables, standardized SMP was performed in 30 patients with hair loss (3 patients with cicatricial and 27 patients with diffuse non-cicatricial alopecia). SMP was also used to create an aesthetically denser hairline. The outcome of the procedure was evaluated using standardized global photographs.

Results:

The ideal parameters were established to achieve standard reproducible results. There was great patient satisfaction and acceptance of the procedure. All the patients showed moderate to great improvement after the procedure with satisfactory scalp coverage. Adverse events were transient which were seen in the form of edema and redness.

Conclusion:

SMP offers a non-medical, tattoo-based cosmetically appealing and effective “cover-up” that hides the unsightly conditions. The cosmetic tattoo placement creates an illusion of thicker hair.

Background

With increasing hair loss, there is a decrease in density of hair, and as a result, the scalp skin can be seen easily due to an increase in contrast between hair and skin. This contrast between the hair and skin can be minimized by providing an illusion using various camouflaging or concealing techniques. Camouflaging techniques such as bio fibers and wigs, or concealers such as hair powder are all temporary methods with their own shortcomings.

Compared to these modalities, tattooing is a permanent concealer and thus has a pivotal role to play in such patients. Scalp micropigmentation (SMP) is an art in the form of stippled painting. Tattooing involves implantation of exogenous metabolically inert colorfast pigments into the skin. SMP is a sophisticated method of placing microdots less than 1 mm in size using one- or three-pronged needles, creating an illusion of hair by decreasing contrast between hair and skin. The process is performed using manual or electrically driven needles, whereby only pigment particles introduced through the skin surface, below the dermal–epidermal junction, are retained by the dermal macrophages and fibroblasts where they reside permanently, producing an indelible change of the skin color in the form of a recognizable pattern or design.[1,2] The terms “micropigmentation” and “dermatography,” which are both coined recently, convey the aesthetic use of tattooing for medical purposes. SMP is not as simple as body tattooing due to the difference in the anatomy of the scalp skin compared to the rest of the body.

Historical Aspects

Skin marking with pigments has been used by people for at least 4,000 years.[3] Tattoos have been found on Egyptian mummies as an indication of worship to a god, and Roman gladiators are known to have used tattoos for identification.[1] In the first half of the 20th century, tattooing was considered fashionable among royalty.[4] The first papers to document unequivocally medical application of tattooing in dermatology and ophthalmology appeared by the mid-1800s.[5,6,7] The word “tattoo” itself was introduced by Captain Cook (1796), who wrote of the Polynesian practice of inlaying black pigments under the skin, known popularly as “tattow” in their native language.

[8] During the past several decades, however, the public perception of tattooing has greatly evolved. Popularity of tattoos and other types of body art, such as piercing, has dramatically increased, especially among adolescents and young adults.[1] The first reported use of micropigmentation on the scalp was in 2001 by Traquina who reported the results of micropigmentation performed in 62 patients with scalp scars.[9] However, this method was crude and the pigmentation was quite detectable. Since then, the procedure of micropigmentation has greatly refined over time.

SMP is a process of intricate maths and science, the outcome of which depends on several variables. The purpose of this article was to create awareness about SMP among plastic surgeons and dermatologists to more readily perform this procedure in patients with hair loss.

Aims and Objectives

1. To study variables and establish optimum parameters that influence the outcome of procedure when performing SMP.
2. To assess response to SMP in patients with hair loss.

Materials and Methods

SMP was performed with a specialized medical tattoo machine using alcohol-based tattoo ink. Fifteen volunteers with hair loss were initially recruited for standardization of SMP protocol after taking consent for the procedure. They were advised to avoid taking aspirin, nonsteroidal anti-inflammatory drugs, vitamin E, Ginkgo biloba, and ginseng 1 week prior to the procedure.

The procedure was performed without using local anesthesia. The area was cleaned and prepped. The pigment was taken in the plastic well and the conical tip of the activated handle was dipped into the ink whereby the ink was sucked into the chamber around the needle by capillary action.

The procedure was now performed with different parameters of each of the following variables and its impact on the outcome was assessed:

1. Angle of the needle to skin: needle insertion at different angles.
2. Depth of needle: insertion at varying depths ranging from 0.3 to 1.2 mm.
3. Pattern of pigmentation: placement of pigment in regular versus random manner.
4. Tattoo ink used: jet black versus black-brown in a ratio of 2:1.
5. Contact time of needle: different contact times with its correlation to pigment deposition.
6. Resistance of scalp: effect of skin suppleness/elasticity/turgidity on pigment deposition.
7. Speed of rotor: impact of varying rotor speed on pigment deposition.
8. Viscosity of dye: fluidity of dye impacting outcome.
9. Needle number: Single-pronged needle was used for hairline designing and triple-pronged needle for the rest of the scalp.

To ascertain the ideal depth of pigment deposition, 1-mm scalp skin biopsy specimen was obtained from the tattooed target site a month after the procedure.

After deriving the optimum parameters for the aforementioned variables, SMP was performed as a standardized procedure in 30 patients with hair loss with cicatricial as well as noncicatricial alopecia. The improvement was graded on global photography with a 7-point rating scale (−3 to +3). Subjective evaluation was conducted on a patient satisfaction scale of 0–3. Both these evaluations were conducted after completion of 6 months after the procedure.