A Single-Center, Split-Face, Double-Blind, Randomized Clinical Trial of the Efficacy of a Trolamine-Containing Topical Emulsion
and a Topical Petrolatum-Based Product In Reducing Redness and Peeling After Treatment With a Microlaser Peel

ABSTRACT

A trolamine-containing topical emulsion (TCTE) has been studied extensively in Europe as a wound-healing agent. A petrolatum-based ointment (PBO) is often used to provide moisture for laser-induced redness and peeling. In a split-face study, 10 subjects applied TCTE to one side of the face and PBO to the other side after treatment with a microlaser peel. TCTE and PBO were applied daily for seven days after the first treatment, then daily for seven days after the second laser treatment one month later. The primary endpoint was to evaluate redness and peeling reduction with both products after microlaser peel treatment. Secondary endpoints were to measure changes in pigmentation, wrinkles, fine lines, texture, and ove rall appearance of the skin. TCTE appears to be at least equivalent to PBO in reducing redness and peeling produced by treatment with a microlaser peel. Differences in skin characteristics after treatment with the microlaser peel did not reach statistical significance, but a definite trend toward greater improvement after the second treatment is suggested for all skin characteristics except hyperpigmentation.

Introduction

Photoaging of the skin most often manifests as dryness, increased laxity, wrinkling, and changes in pigmentation. While effective procedures for treatment are available, many are associated with significant downtime and recovery periods. A trolamine-containing topical emulsion (TCTE) is designed to optimize wound healing by isolating the wound from contaminants and reducing the potential for secondary infection (package insert). TCTE has been studied extensively and been shown to have few adverse effects.¹ TCTE is chemotactic for macrophages and increases the interleukin 1_/Interleukin-6 ratio by suppressing the production of interleukin-6.² Current indications for TCTE include radiation dermatitis,^3-5 full and partial thickness as well as superficial wounds, first and second degree burns (including sunburns), dermal donor and graft-site management, pressure sores, dermal ulcers (including lower leg ulcers), and minor abrasions (package insert). A well-known petrolatum-based ointment (PBO) is often used to protect laser-induced cutaneous redness and provide moisture for resolution. TCTE may also provide similar benefit. The purpose of this investigation was to compare the efficacy of TCTE and PBO in resolving redness and peeling after treatment with a microlaser peel.

MATERIALS & METHODS

Subjects

Subjects included healthy volunteers (skin types I-IV) between 30 and 75 years of age with moderate to severe photodamage. Three of the 13 participants withdrew for personal reasons. The remaining were women aged 37 to 61 years. The study was approved by an independent institutional review board and each subject provided signed informed consent. Inclusion and exclusion criteria are available from the author.

Patients were sequentially assigned to a treatment regimen in a double-blind fashion. During the study, each subject applied TCTE to one randomly determined facial half and PBO to the other side daily for two seven-day periods after microlaser peel treatment. Randomization was performed by non-study personnel. A gentle cleanser was dispensed to subjects on day 0 for use throughout the study. After the seven-day split-face use of TCTE and PBO, subjects were given and instructed to apply a moisturizer with 30 SPF each morning (days 7-29 and 37-59).

Treatment

Subjects received two treatments with a microlaser peel (2940-nm Er:YAG laser) at baseline (day 0) and on visit 5 (day 30). The primary endpoint was resolution of redness and peeling after microlaser peel treatment. Secondary endpoints were changes in pigmentation, wrinkles, fine lines, texture, and overall appearance of the skin.

Assessments

Investigator Resolution Assessment: On day 1, 3, 7, 31, 33, and 37 the investigator graded redness, peeling, blistering, and crusting on the following scale: 0 = none; 1 = minimal; 2 = moderate; 3 = severe. The Kruskal-Wallis test for differences among three or more medians (the non-parametric equivalent to a 1-way ANOVA) was used to test for significant differences among assessment scores on days 1-7 and on days 31-37 for both products.

Investigator Endpoint Analysis: On day 30 (visit 5) and day 60 (visit 60), the investigator graded changes in small wrinkles and fine lines, hyperpigmentation, erythema, skin texture, skin roughness, pore size, and overall skin appearance. Each graded on the following scale: 0 = none; 1 = minimal; 2 = moderate; 3 = significant. The Mann-Whitney test was used to test for significance.

Subject Global Facial Skin Quality Assessment: On day 0 (baseline, visit 1), day 30 (visit 5), and day 60 (visit 9), subjects were asked to grade facial skin quality characteristics. The scale was 1 to 4 for dryness, oiliness, skin texture, skin thickness, and facial skin properties. The scale was 1 to 5 for skin pores, capillaries, lines in the eye and lip areas, and cheek skin. The Kruskal-Wallis test was used to test for significant differences.

Subject Skin Quality Improvement Assessment: On days 30 (visit 5) and 60 (visit 9), subjects were asked if they did or did not detect an improvement or change in fine lines or wrinkles, skin elasticity or tightness, skin texture, skin hydration, global skin appearance, the way the products feel, and the scent of the products. The number of subjects reporting improvement and differences between TCTE and PBO use at 30 days and 60 days were tested for significance by the Mann-Whitney test.

Results

Investigator Resolution Assessment: Comparative median reductions in redness and in peeling scores with daily application of TCTE on one side of the face and PBO on the other side of the face for days 1-7 and days 31-37 are apparent for both products as shown in Figure 1. Scores on days 1, 7, 31, and 33 were zero for both blistering and crusting, so these were not graphed.

Significant reductions were apparent for both TCTE and PBO in redness during both periods. Changes in redness of two patients are shown in Figures 2 and 3. Reduction in peeling with daily application of TCTE on one side of the face and PBO on the other side on days 1-7 and days 31-37. During the first treatment TCTE