Re-pigmentation of Hypopigmentation: Fractional Lasers vs Laser-Assisted Delivery of Bimatoprost vs Epidermal Melanocyte Harvesting System

November 2019 | Volume 18 | Issue 11 | Original Article | 1090 | Copyright © November 2019

Jill S. Waibel MD,a Ashley Rudnick BS,a Kristopher L. Arheart EdD,b Nicole Nagrani MD,c Adrianna Gonzalez MD,c Chloe Gianatasio MSa

ªMiami Dermatology and Laser Institute, Miami, FL

BDepartment of Public Health Science, University of Miami Miller School of Medicine, Miami, FL

cDepartment of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, FL

Abstract
Background: Hypopigmentation is a common cutaneous manifestation that frequently poses a therapeutic challenge for dermatologists. Current treatments have varying efficacies and rarely provide patients with long-term results. However, new treatments are emerging, and head-to-head studies comparing these treatments are warranted.

Methods & Materials: In this prospective, Institutional Review Board (IRB)-approved, double-blinded study, 40 subjects with moderate to severe hypopigmentation were randomized into 1 of 4 treatment arms; non-ablative fractional laser, ablative fractional laser, ablative fractional laser with laser-assisted delivered bimatoprost, and an epidermal harvesting system.

Results: All patients in this study showed improvement regardless of the treatment modality. The average improvement score was calculated on a 0 to 4 scale, and Group 3 (fractional ablative laser and bimatoprost) was found to have a significantly higher average improvement than all other treatments, with 76% of the patients exhibiting at least a grade 3 (over 50%) improvement over the treatment course. Group 1 (non-ablative fractional) also had a significantly higher average score compared with group 2 (fractional ablative laser).

Conclusion: New and emerging therapies have shown promise in helping re-pigmentation of cutaneous hypopigmentation. In this head-to-head trial, it was shown that laser-assisted delivery of bimatoprost had a greater statistically significant improvement compared with 3 possible treatment modalities for stimulation of pigment in medical and cosmetic hypopigmentation.

J Drugs Dermatol. 2019;18(11):1090-1096.

INTRODUCTION

Hypopigmentation is a common cutaneous manifestation that frequently poses a therapeutic challenge for dermatologists. Hypopigmentation can generally be seen after surgery, laser procedures, trauma, or as a consequence of various inflammatory conditions. The pathogenesis of acquired hypopigmentation has been linked to inflammation, whereby various inflammatory factors cause suppression of pigmentation-related signaling, leading to decreased melanin production.1

Hypopigmentation can be a significant issue in patients with skin of color. In prior studies, it has been shown that many hypopigmented skin conditions may have inactive melanocytes that may be stimulated by various modalities to produce pigment.2 Presumably, the target is stimulation of the human epidermal melanocyte. Melanocytes are melanin-producing neural crest-derived cells located in the stratum basale. Once these cells are stimulated, they synthesize melanin in special organelles called melanosomes, which are transported to keratinocytes to induce pigmentation. The depth of the melanocyte depends on the patient skin site, but ranges from 20 micrometers to 141 micrometers (Table 1).3

Current treatment modalities for hypopigmentation include split thickness skin grafting, excisional surgery, exogenous pigment procedures (such as tattooing), dermabrasion, chemical peels, and laser therapy. However, current treatments have varying efficacies and rarely provide patients with long term results.

In the past decade, it has been shown that laser therapy may demonstrate improvement in hypopigmentation of acne and surgical scars. Fractional lasers were among the many devices studied to help improve hypopigmentation in acne and surgical scars. The mechanism of action is hypothesized to be the repopulation of melanocytes in the hypopigmented areas from surrounding hair follicle stem cells and basal melanocytes.4-7