Skin pigmentation. Current concepts and relevance to plastic surgery

Electrophoto-Biomodulation in Aesthetic Treatment of Postburn Hypopigmentation: Clinical Response in Relation to Histopathological Changes

BACKGROUND

Hypopigmentation is a troublesome often-permanent sequelae after burn injury, particularly in dark races. A number of methods have been described to treat this phenomenon. In this work, we are going to study the effect of E light (intensive pulsed light+radiofrequency+cooling) in repigmentation of partial thickness and full thickness burn wounds in adult patients and light microscopic changes of biopsy material at various stages of repigmentation.

PATIENTS AND METHODS

In this study, 24 patients with postburn hypopigmentation were selected and E light was used, using different filters, according to the skin color. The intensive pulsed light fluence varied between 38 and 42 J. Radiofrequency fluencies varied between 6 and 10 J, and the spot diameter was 8 × 32 mm. Pulse durations of 2 to 7 milliseconds and pulse delays of 15 to 30 milliseconds were used on all patients.The patients were evaluated by comparing pretreatment and posttreatment photos. Skin biopsies were taken from depigmented area before and after interventions. Melanocytes were immunostained using Hwenty-four homatropine methylbromide 45 and were counted in ×200 magnification fields. Melanin can be demonstrated after staining with hematoxylin and eosin.

RESULTS

Seventeen cases were evaluated as excellent, 4 cases were evaluated as good, and 3 cases were evaluated as fair, but all patients stressed that their wounds have been improved.Light microscopy at 6 weeks posttreatment also confirmed the increased melanocyte number per field in all cases.

CONCLUSIONS

E light induced significant overall clinical improvement in postburn hypopigmentation, particularly when E light was applied early after burn.

The clinical experience for treating post-burn depigmentation with tiny epidermal particles graft

The critical problem of post-burn depigmentation is the lacking normal melanocytes. Auto-skin grafting and autologous non-cultured epidermal cell suspension have been used to improve the appearance. However, a large amount of skin graft is required of donor sites in the former method, while the latter method is thought to be complicated and costly. This study is designed to generalise the experience of tiny epidermal particles graft (TEPG) for treating post-burn depigmentation. From 2012 to 2013, 30 consecutive patients with depigmentation caused by burn injuries were divided into I and II group. I group: 15 cases (11 males and 4 females) were treated by the TEPG. II group: 15 patients (10 males and 5 females) were treated by suction blister epidermal skin graft (SBEG). Imagine-Pro Plus software was used to evaluate the size of repigmentation (RP) 12 months post-surgery. SPSS software 13.0 was used to evaluate the data. The optimum rate of RP was defined as more than 75% (RP > 75%) when excellent RP was defined as more than 90% (>90%). All patients were followed up for 12 months. The mean size of RP in two groups demonstrated that there were statistically significant differences in pigmentation between the two groups (P = 0·002), while there was no significant difference in the other factors (gender, site and age). No infection occurred in the recipient site. Pathological result showed that melanocytes existed at the basal layer of resurfacing skin. Optimum RP (RP > 75%) was seen in 12 patients in I group and 9 patients in II group. Excellent RP was achieved in 14 cases in I group and 10 patients in II group. Excellent RP can be obtained by the abovementioned two surgical techniques. In contrast to SBEG, TEPG is less traumatic, and definite effects can be guaranteed. It is a preferred treatment, especially for those patients who suffer from large depigmented lesions.

Scar treatment variations by skin type

Patients and clinicians use skin color attributes such as color uniformity, color distribution, and texture to infer physiologic health status. Normalization of skin color, surface texture, and height are important treatment goals in the treatment of scars. Skin color, structure, and response to trauma, vary with ethnicity. The incidence of hypertrophic and keloid scar formation is influenced by these inherent skin attributes. Skin type influences the response to various modalities including laser therapy and surgical intervention, and skin differences must be considered in treatment planning to achieve optimal results.

Comparison of intradermal injection of autologous epidermal cell suspension vs. spraying of these cells on dermabraded surface of skin of patients with post-burn hypopigmentation

Introduction:

One of the most important complications after burning is hypo/depigmentation. This study was designed to compare two methods of cell spray and intradermal injection of epidermal cell suspension for treatment of burn induced hypopigmentation.

Material and Methods:

In this study, 28 patients with post burn hypo/depigmentation were selected and divided in 2 groups. A small skin biopsy was taken from normal skin of patients in operation room and epidermal cell suspension was prepared using NaBr 4N and trypsin. In the first group, the epidermal cell suspension was sprayed on the wound surface and then the area was dressed with amniotic membrane and gauze. In the second group, the cell suspension was injected in intradermal manner in the hypopigmented area. The patients were followed up and to evaluate the effect of the cells, photos were taken from the area before operation and also at follow-up. Clinical evaluation was done by the surgeon and a clinical score between “0” to “4” was used to demonstrate the clinical status from poor to excellent pigmentation. Skin biopsies were taken from depigmented area before and after interventions. Melanocytes were stained using anti S100 antibody and were counted in ×400 magnification fields.

Results:

Eighteen patients were in cell spray and 10 were in cell injection groups. Mean change of pigmentation in two group showed that there was no statistical significant differences in pigmentation between two groups, (P value = 0.52) although a limited improvement in pigmentation status was observed in both groups. Regarding melanocyte numbers per field, there was not a significant difference between two groups and also before and after interventions, but melanocyte number increased after treatment in both groups.

Conclusion:

We did not find noticeable differences between cell spray and intradermal injection methods. Although both methods showed a limited effect on pigmentation of depigmented skin, the clinical results were not satisfactorily for both patients and clinicians.

Repigmentation of cutaneous scars depends on original wound type

Cutaneous scarring is currently an inevitable outcome following skin injury. Abnormal pigmentation within scars makes them more noticeable, causing distress for patients, particularly as there is no reliable and effective treatment available to date. The Duroc pig, known to scar badly, was used to investigate repigmentation of scars resulting from three different wound types: incisional, partial thickness excisional and full thickness excisional. Wounds were created on the backs of Duroc pigs and the resulting scars harvested at days 35, 56, 70 and 90 days post-injury. Scars were processed for histology and immunohistochemistry, quantitatively analysed using image analysis software and subjected to statistical analysis. Photographs of the macroscopic appearance of scars were scored for pigmentation using a visual analogue scale. Results demonstrated temporal and spatial differences in melanocyte repopulation and function within scars from different wound types. The microscopic pigment deposition did not correlate with macroscopic appearances in mature scars. Pigmentation of scars is dependent on the width and depth of wounds. This study has provided important information on which we can base future studies to investigate factors controlling the repigmentation of scars.

Update on techniques for the quantitation of facial skin characteristics

The purpose of this article is to review the strategies and methods for quantifying treatment outcomes, perhaps defined by the consumer/patient as a "decrease in perceived age." The demand for the rejuvenation of facial skin is expected to increase as the population ages and seeks optimal outcomes from the array of available treatment modalities. This information will be of value to the plastic surgeon in collaborating with patients on evaluation and treatment strategies.

Abnormal pigmentation within cutaneous scars: A complication of wound healing

Abnormally pigmented scars are an undesirable consequence of cutaneous wound healing and are a complication every single individual worldwide is at risk of. They present a challenge for clinicians, as there are currently no definitive treatment options available, and render scars much more noticeable making them highly distressing for patients. Despite extensive research into both wound healing and the pigment cell, there remains a scarcity of knowledge surrounding the repigmentation of cutaneous scars. Pigment production is complex and under the control of many extrinsic and intrinsic factors and patterns of scar repigmentation are unpredictable. This article gives an overview of human skin pigmentation, repigmentation following wounding and current treatment options.

The evaluation of relevant factors influencing skin graft changes in color over time

BACKGROUND

Objective studies evaluating the relevant factors that affect skin graft changes in color over time have yet to be published.

OBJECTIVE

Therefore, the patterns of the grafted skin's color changes and the presence of relevant factors were analyzed statistically.

MATERIALS AND METHODS

The study included 107 skin grafts in 107 subjects. Using a chromameter, the colors of skin graft, the area adjacent to the recipient site, and the donor site were measured. The grafted skin's color changes and the color difference were analyzed with respect to several factors.

RESULTS

Over time, the grafted skin became lighter, redness decreased, yellowness increased, and the color difference decreased. As the donor site was lighter, the grafted skin was lighter and less red. The grafted skin was lighter in females than in males. The skin graft type was not related to the lightness and the redness. The grafted skin was lightest in the upper arm and darkest in the lower leg. The grafted skin was lighter in Fitzpatrick Skin Type III, followed by Type IV and then Type V.

CONCLUSION

The factors that affected the skin graft's lightness were time, the lightness of the donor, sex, the hand, the foot, and Fitzpatrick skin type.

Epidemiology, aetiology and management of abnormal scarring: a review of the literature

Keloid and hypertrophic scars are the result of abnormal processes in scar formation. This paper reviews the literature and the many debates concerning the processes that cause abnormal scarring.

A clinical, prospective, randomized, double-blind trial comparing skin whitening complex with hydroquinone vs. placebo in the treatment of melasma

OBJECTIVES

To compare, in a double-blind, randomized, prospective study, the clinical improvement of hyperpigmentation in 30 patients with melasma using hydroquinone or skin whitening complex topically on one side of the face vs. a placebo cream on the other. The study was performed during the period November 2000 to March 2001 at the Federal University of São Paulo, Escola Paulista de Medicina.

METHODS

Thirty patients received three tubes of cream and were divided into two groups: group 1, one tube containing hydroquinone 4% cream and one tube containing placebo to be applied to opposite sides of the face at night, and standardized sunscreen [sun protection factor (SPF) 25] for daily use; group 2, one tube containing skin whitening complex 5% cream and one tube containing placebo to be applied to opposite sides of the face at night, and standardized sunscreen (SPF 25). All of the tubes had the same appearance and the creams had the same characteristics. The only person who knew what was being used by each patient on each side of the face was the pharmacist. A professional photographer took photographs before and after treatment, which lasted for 3 months. Clinical evaluation was performed by two independent observers and by the patients themselves. Statistical evaluation was by the chi-squared and kappa methods.

RESULTS

Twenty-five patients completed the study, with an overall improvement of 72% in comparison with placebo. Group 1 (hydroquinone and placebo) presented an improvement of 76.9% with 25% side-effects, and group 2 (skin whitening complex and placebo) presented an improvement of 66.7% with 0% side-effects.

CONCLUSIONS

Both depigmentation agents were useful in the treatment of melasma. The hydroquinone group presented more collateral effects than the skin whitening complex group. Considering that the patients showed Fitzpatrick skin types IV to VI and the study was conducted in the summer, skin whitening complex seems to be an excellent choice for the treatment of melasma.

A role for lasers in the treatment of pigmented skin grafts

The development of aberrant pigmentation represents an unwelcome complication to an otherwise successful split skin graft resulting in a loss of colour match and, so it follows, of cosmesis. We present two cases where lasers have been successful in the treatment of this problem.

Management of hypopigmentation following burn injury

Hypopigmentation is a troublesome often permanent sequelae following burn injury, particularly in dark races. A number of methods have been described to treat this phenomenon ranging from primary closure, split skin and particulate grafting as well as semipermanent and permanent camouflage. This article reviews the pathophysiology of this condition and discusses the indications for using each technique as well as the potential for future developments in melanocyte culture.

Repigmentation after burn injury in the guinea-pig

The normal process of repigmentation of small partial- and full-thickness burn wounds in the guinea-pig has been studied visually, and by light microscopy and transmission electron microscopy of biopsy material, at various stages of healing. Repigmentation proceeded apace with re-epithelialization and occurred progressively from the periphery to the centre of the wound or scar. There was an initial lag period of 1 to 2 weeks post burn during which the melanocytes and melanin content of the regenerated epithelium were below or around normal control levels. Thereafter, the melanocytes and melanin were above normal levels and correlated with hyperpigmentation of the scar epithelium. Electron microscopy at 6 and 7 weeks post burn also confirmed the increased melanogenic and cytochrine activity of the melanocytes during this phase of burn healing.

Dermabrasion of the skin: Prevention and/or treatment of hyperpigmentation

Dermabrasion of the face for multiple conditions requiring reconstructive surgery is still a valuable tool for the plastic and reconstructive surgeon. This article deals specifically with one of the most important complications, namely, hyperpigmentation.The specific effect of estrogens on hyperpigmentation and the manner of dealing with it by the use of hydroquinone ointment are discussed. Illustrative case histories and photographs are shown. The reversal of the hyperpigmentation caused by estrogens and treated by hydroquinone ointment are explained, and the conclusion is reached that this management leads to permanent satisfactory results.