Treatment of hypopigmented burn hypertrophic scars with short-term topical tacrolimus does not lead to repigmentation.

OBJECTIVES: Dyschromia is an understudied aspect of hypertrophic scar (HTS). The use of topical tacrolimus has successfully shown repigmentation in vitiligo patients through promotion of melanogenesis and melanocyte proliferation. It was hypothesized that HTSs treated with topical tacrolimus would have increased repigmentation compared to controls. METHODOLOGY: Full-thickness burns in red Duroc pigs were either treated with excision and meshed split-thickness skin grafting or excision and no grafting, and these wounds formed hypopigmented HTSs (n = 8). Half of the scars had 0.1% tacrolimus ointment applied to the scar twice a day for 21 days, while controls had no treatment. Further, each scar was bisected with half incurring fractional ablative CO2 laser treatment before topical tacrolimus application to induce laser-assisted drug delivery (LADD). Pigmentation was evaluated using a noninvasive probe to measure melanin index (MI) at Days 0 (pretreatment), 7, 14, and 21. At each timepoint, punch biopsies were obtained and fixed in formalin or were incubated in dispase. The formalin-fixed biopsies were used to evaluate melanin levels by H&E staining. The biopsies incubated in dispase were used to obtain epidermal sheets. The ESs were then flash frozen and RNA was isolated from them and used in quantitative reverse transcription polymerase chain reaction for melanogenesis-related genes: Tyrosinase (TYR), TYR-related protein-1 (TYRP1), and dopachrome tautomerase (DCT). Analysis of variance test with Sídák's multiple comparisons test was used to compare groups. RESULTS: Over time, within the grafted HTS and the NS group, there were no significant changes in MI, except for Week 3 in the -Tacro group. (+Tacro HTS= pre = 685.1 ± 42.0, w1 = 741.0 ± 54.16, w2 = 750.8 ± 59.0, w3 = 760.9 ± 49.8) (-Tacro HTS= pre = 700.4 ± 54.3, w1 = 722.3 ± 50.7, w2 = 739.6 ± 53.2, w3 = 722.7 ± 50.5). Over time, within the ungrafted HTS and the NS group, there were no significant changes in MI. (+Tacro HTS= pre = 644.9 ± 6.9, w1 = 661.6 ± 3.3, w2 = 650.3 ± 6.2, w3 = 636.3 ± 7.4) (-Tacro HTS= pre = 696.8 ± 8.0, w1 = 695.8 ± 12.3, w2 = 678.9 ± 14.0, w3 = 731.2 ± 50.3). LADD did not lead to any differential change in pigmentation compared to the non-LADD group. There was no evidence of increased melanogenesis within the tissue punch biopsies at any timepoint. There were no changes in TYR, TYRP1, or DCT gene expression after treatment. CONCLUSION: Hypopigmented HTSs treated with 0.1% tacrolimus ointment with or without LADD did not show significantly increased repigmentation. This study was limited by a shorter treatment interval than what is known to be required in vitiligo patients for repigmentation. The use of noninvasive, topical treatments to promote repigmentation are an appealing strategy to relieve morbidity associated with dyschromic burn scars and requires further investigation.

The 730 nm picosecond titanium sapphire laser for treatment of café-au-lait macules in all skin types.

OBJECTIVES: Café-au-lait macules (CALM) are benign birthmarks presenting as uniformly pigmented, well demarcated, brown patches that can be distressing to patients, especially when located in cosmetically sensitive areas. As with all pigmentary lesions in skin of color patients, CALMs have been particularly challenging to treat. Here we present the first case series characterizing treatment parameters and clinical outcomes utilizing the 730-nm picosecond titanium sapphire laser for the treatment of CALMs. This device provides an additional safe and effective treatment option for these challenging cases. METHODS: We performed a retrospective review of patients treated at a single institution between April 2021 and December 2023. Clinical photographs were graded by 3 outside board-certified dermatologists using a 5-point visual analog scale. RESULTS: Fourteen patients (age range: 10 months-66 years, mean age: 27.4 years, Fitzpatrick skin types II-VI) were treated for CALM on the face (11) or body (3). On average, patients received 4.3 treatments, with treatment intervals ranging from 4 to 40 weeks. Treatment remains ongoing with the 730-nm picosecond laser for eight patients. Overall, patients were rated to have a mean improvement of 26%-50%. Two patients (FST III and VI) achieved 100% clearance after 4-5 treatment sessions. Our study included four patients whose CALM were of the smooth bordered "coast of California" subtype, three of whom had a mean improvement rating of only 1%-25%. The fourth patient had near complete resolution. Follow up for these patients has ranged from 6 weeks to 1.5 years. Of the patients treated, one patient experienced transient post-inflammatory hyperpigmentation and another transient post-inflammatory hypopigmentation, while a third patient experienced mild persistent guttate hypopigmentation. Three patients experienced partial recurrence indicating that maintenance treatments may be needed in some patients. CONCLUSION: The 730-nm picosecond titanium sapphire laser is a safe and efficacious treatment option, in the right morphologic setting, to improve the cosmetic appearance of CALMs in a wide range of ages and skin types. To our knowledge, this is the first reported treatment of CALMs with picosecond lasers in FST V and VI patients. Our study also supports prior studies which have found that CALM with smooth-bordered "coast of California" morphology have a poor response to laser therapy as compared to those with jagged or ill-defined bordered "coast of Maine" morphology.

Efficacy and safety of picosecond laser for the treatment of melasma: a systematic review and meta-analysis.

Multiple laser modalities have been used for melasma treatment. However, the effectiveness of picosecond laser in treating melasma remains unclear. This meta-analysis investigated the effectiveness and safety of picosecond laser for melasma treatment. Randomized controlled trials (RCTs) comparing picosecond laser with conventional treatment for melasma were searched through five databases. The melasma area severity index (MASI)/modified MASI (mMASI) was used to quantify the degree of melasma improvement. Standardized mean differences and 95% confidence intervals were calculated using Review Manager for result standardization. Six RCTs, which used picosecond laser at 1064, 755, 595, and 532 nm wavelengths, were included herein. Picosecond laser significantly reduced the MASI/mMASI, but the results were highly heterogeneous (P = 0.008, I2 = 70%). In the subgroup analysis of 1064 and 755 nm picosecond lasers, 1064 nm picosecond laser significantly reduced the MASI/mMASI with no significant side effects (P = 0.04). Meanwhile, 755 nm picosecond laser did not significantly improve the MASI/mMASI compared with topical hypopigmentation agents (P = 0.08) and caused post-inflammatory hyperpigmentation. Other laser wavelengths could not be used in the subgroup analysis owing to an insufficient sample size. Picosecond laser at 1064 nm is safe and effective for melasma treatment. Picosecond laser at 755 nm is not superior to topical hypopigmentation agents in treating melasma. The exact efficacy of other wavelengths of picosecond laser for melasma treatment remains to be verified in large-scale RCTs.

Laser therapy for treating hypertrophic and keloid scars.

BACKGROUND: Hypertrophic and keloid scars are common skin conditions resulting from abnormal wound healing. They can cause itching, pain and have a negative physical and psychological impact on patients' lives. Different approaches are used aiming to improve these scars, including intralesional corticosteroids, surgery and more recently, laser therapy. Since laser therapy is expensive and may have adverse effects, it is critical to evaluate the potential benefits and harms of this therapy for treating hypertrophic and keloid scars. OBJECTIVES: To assess the effects of laser therapy for treating hypertrophic and keloid scars. SEARCH METHODS: In March 2021 we searched the Cochrane Wounds Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL EBSCO Plus and LILACS. To identify additional studies, we also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses, and health technology reports. There were no restrictions with respect to language, date of publication, or study setting. SELECTION CRITERIA: We included randomised controlled trials (RCTs) for treating hypertrophic or keloid scars (or both), comparing laser therapy with placebo, no intervention or another intervention. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, extracted the data, assessed the risk of bias of included studies and carried out GRADE assessments to assess the certainty of evidence. A third review author arbitrated if there were disagreements. MAIN RESULTS: We included 15 RCTs, involving 604 participants (children and adults) with study sample sizes ranging from 10 to 120 participants (mean 40.27). Where studies randomised different parts of the same scar, each scar segment was the unit of analysis (906 scar segments). The length of participant follow-up varied from 12 weeks to 12 months. All included trials had a high risk of bias for at least one domain: all studies were deemed at high risk of bias due to lack of blinding of participants and personnel. The variability of intervention types, controls, follow-up periods and limitations with report data meant we pooled data for one comparison (and only two outcomes within this). Several review secondary outcomes - cosmesis, tolerance, preference for different modes of treatment, adherence, and change in quality of life - were not reported in any of the included studies. Laser versus no treatment: We found low-certainty evidence suggesting there may be more hypertrophic and keloid scar improvement (that is scars are less severe) in 585-nm pulsed-dye laser (PDL) -treated scars compared with no treatment (risk ratio (RR) 1.96; 95% confidence interval (CI): 1.11 to 3.45; two studies, 60 scar segments). It is unclear whether non-ablative fractional laser (NAFL) impacts on hypertrophic scar severity when compared with no treatment (very low-certainty evidence). It is unclear whether fractional carbon dioxide (CO2) laser impacts on hypertrophic and keloid scar severity compared with no treatment (very low-certainty evidence). Eight studies reported treatment-related adverse effects but did not provide enough data for further analyses. Laser versus other treatments: We are uncertain whether treatment with 585-nm PDL impacts on hypertrophic and keloid scar severity compared with intralesional corticosteroid triamcinolone acetonide (TAC), intralesional Fluorouracil (5-FU) or combined use of TAC plus 5-FU (very low-certainty evidence). It is also uncertain whether erbium laser impacts on hypertrophic scar severity when compared with TAC (very low-certainty evidence). Other comparisons included 585-nm PDL versus silicone gel sheeting, fractional CO2 laser versus TAC and fractional CO2 laser versus verapamil. However, the authors did not report enough data regarding the severity of scars to compare the interventions. As only very low-certainty evidence is available on treatment-related adverse effects, including pain, charring (skin burning so that the surface becomes blackened), telangiectasia (a condition in which tiny blood vessels cause thread-like red lines on the skin), skin atrophy (skin thinning), purpuric discolorations, hypopigmentation (skin colour becomes lighter), and erosion (loss of part of the top layer of skin, leaving a denuded surface) secondary to blistering, we are not able to draw conclusions as to how these treatments compare. Laser plus other treatment versus other treatment: It is unclear whether 585-nm PDL plus TAC plus 5-FU leads to a higher percentage of good to excellent improvement in hypertrophic and keloid scar severity compared with TAC plus 5-FU, as the certainty of evidence has been assessed as very low. Due to very low-certainty evidence, it is also uncertain whether CO2 laser plus TAC impacts on keloid scar severity compared with cryosurgery plus TAC. The evidence is also very uncertain about the effect of neodymium-doped yttrium aluminium garnet (Nd:YAG) laser plus intralesional corticosteroid diprospan plus 5-FU on scar severity compared with diprospan plus 5-FU and about the effect of helium-neon (He-Ne) laser plus decamethyltetrasiloxane, polydimethylsiloxane and cyclopentasiloxane cream on scar severity compared with decamethyltetrasiloxane, polydimethylsiloxane and cyclopentasiloxane cream. Only very low-certainty evidence is available on treatment-related adverse effects, including pain, atrophy, erythema, telangiectasia, hypopigmentation, regrowth, hyperpigmentation (skin colour becomes darker), and depigmentation (loss of colour from the skin). Therefore, we are not able to draw conclusions as to how these treatments compare.  AUTHORS' CONCLUSIONS: There is insufficient evidence to support or refute the effectiveness of laser therapy for treating hypertrophic and keloid scars. The available information is also insufficient to perform a more accurate analysis on treatment-related adverse effects related to laser therapy. Due to the heterogeneity of the studies, conflicting results, study design issues and small sample sizes, further high-quality trials, with validated scales and core outcome sets should be developed. These trials should take into consideration the consumers' opinion and values, the need for long-term follow-up and the necessity of reporting the rate of recurrence of scars to determine whether lasers may achieve superior results when compared with other therapies for treating hypertrophic and keloid scars.

Comparison of the safety and efficacy of low fluence Q-switched 1064-nm and conventional Q-Switched 755-nm lasers in the treatment of café-au-lait macules: A prospective self-controlled trial.

BACKGROUND: Conventional high fluence Q-switched (HFQS) Alexandrite 755-nm are widely used in clinical café-au-lait macules (CALMs) treatment. There have been recent concerns regarding the efficacy and safety of low fluence Q-switched (LFQS) Nd: YAG 1064-nm lasers. OBJECTIVE: To evaluate the efficacy and safety of the conventional HFQS and LFQS laser in the treatment of CALMs. METHODS: Within 3 months, 20 patients underwent prospective self-controlled split-lesion treatments with HFQS once or twice depending on the recovery rate, and with LFQS six times biweekly. Then the more effective laser was selected for continued treatments. Efficacy outcomes were evaluated by a visual analog scale (VAS) biweekly during the comparative trail. Recovery process, side effects and recurrence were recorded during the trial and follow-up visit. Patient and physician preferences for laser selection were also recorded. RESULTS: The average VAS scores of areas treated with HFQS and LFQS were 2.92 ± 0.86 and 2.93 ± 1.13, respectively (p > 0.05). The most significant efficacy change of LFQS was after the fourth laser treatment (VAS score: 1.82-2.37, p < 0.001). 11 lesions treated with LFQS and 7 with HFQS achieved an optimal treatment response (3.67 ≤ VAS ≤ 4). Three patients relapsed on one side (one on LFQS, two on HFQS) and five on both sides. Adverse effects included temporary hypopigmentation, hyperpigmentation, uneven pigmentation, and mottled hypopigmentation. Doctors thought 80% of patients were suitable for LFQS. 70% of patients preferred LFQS posttreatment. CONCLUSIONS: The efficacy difference between the LFQS 1064-nm laser and HFQS 755-nm laser in treating CALMs in a 3-month comparative trial was statistically insignificant. LFQS is preferred by doctors and patients and is likely to help more patients achieve treatment efficacy than the HFQS within a short time, with fewer temporary adverse reactions, and a more even pigmentation. But it can cause mottled hypopigmentation. The LFQS had obvious lesion clearance after the fourth treatment.

Laser Treatment of Hypopigmentation in Scars: A Review.

BACKGROUND: Despite history of multiple treatment modalities, repigmentation of hypopigmented scars remains a difficult clinical problem. OBJECTIVE: The purpose of this review is to evaluate the literature on laser and combination laser plus adjunct topical therapy for hypopigmented burn and traumatic scars. MATERIALS AND METHODS: A search on PubMed and on Oxford Academic was conducted with additional relevant literature obtained from reference lists. RESULTS: Treatment regimens that address hypopigmentation within scars were reviewed. A combination of nonablative fractional or ablative fractional laser treatment with topical prostaglandin analogue with or without topical retinoid were found to result in superior repigmentation. CONCLUSION: Reliable improvement of hypopigmentation in scars after laser treatment is challenging. Laser can achieve success in some cases. Ultraviolet laser can achieve modest repigmentation; however, results are short-lived and require continued re-treatment. Modest improvement in pigmentation is seen with nonablative fractional laser or ablative fractional laser alone and enhanced repigmentation is demonstrated when combining fractional laser resurfacing with topical application of synthetic prostaglandin analogues and other known modulators of melanogenesis.

Hypopigmentation in Extramammary Paget Disease Is an Important Prognostic Factor for High Recurrence Rate and Poor Surgical Outcome.

BACKGROUND: Several studies have reported the presence of hypopigmentation in extramammary Paget disease (EMPD). However, an in-depth analysis regarding its clinical implication is lacking. OBJECTIVE: To evaluate the clinical characteristics of EMPD in the Korean population and to determine the implication of hypopigmentation on clinical outcomes. METHODS: We retrospectively reviewed 124 cases of EMPD who underwent surgical treatment from a single tertiary hospital from December 2005 to March 2019. Baseline characteristics of the patients and hypopigmentation patterns were analyzed. Moreover, the number of stages of Mohs micrographic surgery (MMS) and recurrence rate were evaluated in relation to the hypopigmentation. RESULTS: A total of 67.7% (n = 84) of the patients showed hypopigmentation. The adjusted odds ratio for recurrence in the hypopigmented group was 5.980, which was statistically significant (95% confidence interval = 1.347-26.553, p-value = 0.019). Furthermore, the average number of MMS stages was 2.92 in the hypopigmentation group, compared with 1.82 in the nonhypopigmentation group (p-value = .0016). CONCLUSION: Hypopigmented lesions may disguise the tumor margin, thus raising the recurrence rate after surgery and the number of stages of MMS. The hypopigmentation status must be considered when deciding the surgical margin.

Common Dermatologic Procedures and the Associated Complications Unique to Skin of Color.

BACKGROUND: The skin of color (SOC) population in the United States continues to grow, and these patients are undergoing various cosmetic and surgical procedures at increasing rates. There is a paucity of data on the potential complications associated with surgical and cosmetic procedures in this patient population. OBJECTIVE: We aim to educate dermatologic surgeons and clinicians on surgical and cosmetic procedures in patients of color and increase awareness of the potential complications unique to this patient population. MATERIALS AND METHODS: A thorough PubMed literature search was performed to conduct this review. RESULTS: There are a number of complications in SOC that require special attention, including keloids, postoperative infections, postinflammatory hyperpigmentation, and hypopigmentation. There are also various precautions to consider when performing cosmetic procedures, such as neurotoxin and filler injections, laser therapy, microneedling, and chemical peels. CONCLUSION: Dermatologists should be aware of the potential cosmetic and surgical complications of this growing patient population to provide optimal evidence-based medical care.

Idiopathic guttate hypomelanosis: Presentation and Management.

Idiopathic guttate hypomelanosis (IGH) is a benign, typically asymptomatic, acquired leukoderma characteristically affecting mature individuals. Although the etiopathogenesis is unclear, chronic sun exposure and senile degeneration are important triggers. Researchers have been engaged in a continuous effort to unveil the gray areas encompassing different aspects of IGH pathogenesis. IGH is a clinical diagnosis; however, histopathology and dermoscopy may aid in quetionable cases. Patients often seek cosmetic treatment. There has been no standard therapy for this condition. Newer treatment modalities range from topical agents to procedure-based therapies and have enhanced the therapeutic armamentarium. Here we discuss the pathogenesis, presentation, and management of IGH.

Intense Pulsed Light: A Methodical Approach to Understanding Clinical Endpoints.

BACKGROUND: Intense Pulsed Light (IPL) is a non-coherent polychromatic broadband filtered flashlamp that emits light in the spectrum of approximately 400–1200 nm. Its effects on photorejuvenation are well documented. The goal of this study is to help practitioners better conceptualize and fine tune IPL device settings in order to produce the most effective and safest clinical outcome. MATERIALS/METHODS: This was a prospective study testing several filters (515 nm; 560 nm; 590 nm and 530–650; 900–1200 nm vascular filter), fluences, pulse durations, and pulse numbers (ie, multiple sequence pulsing or MSP) with a new IPL system. RESULTS: Post-procedure erythema response was more pronounced with increasing fluence, decreasing wavelength, fewer pulses and shorter pulse duration. The exception was the 515 nm filter with regard to pulse duration, which was observed to have a more pronounced response with longer pulse durations. The overall clinical outcome at the 4-week follow-up visit demonstrated greatest improvement in erythema and pigmentation using the 515 nm filter on a Fitzpatrick Skin Type III individual. CONCLUSION: Greatest clinical endpoint response at 4-week follow-up was observed with more robust initial responses. This was most apparent at higher fluence levels and fewer pulse counts. However, when the IPL is pushed to aggressive parameters, there is risk of hypopigmentation and hair loss as seen in this case study. Skin type is an important consideration when using IPL and MSP adds to its safety profile. J Drugs Dermatol. 2021;20(2):203-207. doi:10.36849/JDD.5638.

Comparison of a picosecond alexandrite laser versus a Q-switched alexandrite laser for the treatment of nevus of Ota: A randomized, split-lesion, controlled trial.

BACKGROUND: Novel picosecond lasers have been available for various pigmentary disorders. However, there are limited data directly comparing picosecond lasers and Q-switched lasers for treatment of nevus of Ota. OBJECTIVE: To compare the efficacy and safety of a picosecond alexandrite laser (PSAL) with a Q-switched alexandrite laser (QSAL) for the treatment of nevus of Ota. METHODS: Each lesion of 56 enrolled participants was split into 2 parts and randomly assigned to either the PSAL or QSAL treatment arm. Each lesion was treated in up to 6 sessions in 12-week intervals. Efficacy and safety were determined using blinded visual evaluation and self-report at each follow-up visit. RESULTS: The PSAL arm achieved a significantly better clearance (5-point scale, PSAL 4.53 vs QSAL 4.0) with fewer sessions (PSAL 5.26 vs QSAL 5.87) and less severe pain (Visual Analog Scale, PSAL 5.61 vs QSAL 6.40). Patients were more satisfied with PSAL than QSAL (Likert scale, 4.5 vs 4.0). Occurrences of postinflammatory hyperpigmentation (PSAL 26% vs QSAL 34%) and hypopigmentation (PSAL 21% vs QSAL 47%) were also lower in PSAL than QSAL arm. LIMITATIONS: Lack of objective assessments and outcome measures. CONCLUSION: PSAL demonstrated better clinical results and fewer adverse events than QSAL for the treatment of nevus of Ota.

Poikilodermatous plaque-like hemangioma: A benign vasoformative entity with reproducible histopathologic and clinical features.

Poikilodermatous plaque-like hemangioma (PPLH) is a recently described benign vasoformative entity with only 16 cases reported to date. We present an additional case of a 90-year-old male who presented with a 2-year history of a relatively large, asymptomatic, atrophic plaque on his left buttock. The lesion was initially smaller and grew before stabilizing in size. The patient denied preceding trauma or injury at this site as well as the presence or history of any similar lesions elsewhere. Physical examination revealed a reniform atrophic pink plaque with peripheral hyperpigmentation and overlying cigarette paper wrinkling. Given this appearance, scar or post-inflammatory changes were favored clinically, but lack of preceding trauma raised clinical concerns for poikilodermatous mycosis fungoides. Given the location and appearance, a broad shave biopsy was performed to rule out mycosis fungoides. Histopathologic examination revealed an increased density of superficial endothelial-cell-lined vessels, telangiectasias with sludging and congestion of superficial dermal vessels and loss of elastic tissue fibers in the lesional area. These findings, in the context of the clinical history, were consistent with this newly described hemangioma. We present this case to increase awareness amongst dermatopathologists of the reproducible clinical and histopathologic findings of this new benign vasoformative entity.

The Woronoff Ring in Psoriasis and the Mechanisms of Postinflammatory Hypopigmentation.

The Woronoff ring is a ring-like hypopigmentation zone around regressing psoriasis lesions. Although it was first described more than 100 years ago, its aetiology has remained a mystery. Recent insights into the pathogenesis of psoriasis can now explain the origin of the Woronoff ring. Psoriasis involves an HLA-class I-restricted autoimmune response of CD8+ T cells against melanocytes in the epidermis. The pathogenic CD8+ T cells are not cytotoxic, but are characterized by the production of interleukin-17, interleukin-22 and tumour necrosis factor-α. Interleukin-17 and tumour necrosis factor-α act synergistically on melanocytes by increasing proliferation while inhibiting melanogenesis. This reduces the cellular melanin content despite an increased number of melanocytes in psoriatic lesions. As a consequence, during healing the prior influence of interleukin-17 and tumour necrosis factor-α, despite the increased density of melanocytes, leaves a hypopigmented zone at the edge of regressing psoriasis lesions, which becomes visible as the Woronoff ring. This mechanism can explain a long-discussed puzzling phenomenon in dermatology.

Treatment of Laser-Responsive Dermal Pigmentary Conditions in Type III-IV Asian Skin With a 755-nm Picosecond Pulse Duration Laser: A Retrospective Review of Its Efficacy and Safety.

BACKGROUND: Picosecond lasers have become very popular in the treatment of hyperpigmentation. OBJECTIVE: Evaluating the efficacy and safety of picosecond 755-nm laser in treatment of nevi of Ota (NO) and Hori's nevi (HN) in Asians with Fitzpatrick skin Types III/IV. METHODS: A retrospective review of patient records at the National Skin Center, Singapore, from 2015 to 2017. Three independent blinded dermatologists assessed pre-and-post treatment photographs using the physician's global assessment (PGA) score (0-clear, 1-almost clear, 2-mild, 3-moderate, and 4-severe). RESULTS: There were 18 cases of NO and 11 cases of HN. Mean treatment sessions were 2.22 (NO; range 1-6) and 3.82 (HN; range 1-6). In the NO group, mean pre-and-post treatment PGA scores were 3.1 and 1.3, respectively (1.8 point change, p-value 0.0002), and average fluence used was 2.02 J/cm (range: 1.02-2.38). In the HN group, mean pre-and-post treatment PGA scores were 2.6 and 1.1, respectively (1.5 point change, p-value 0.004), and average fluence was 2.08 J/cm (range: 1.98-3.40). Eleven patients (37.9%) experienced postlaser erythema, and 1 (3.4%) patient developed transient postlaser hypopigmentation. No permanent hyper/hypopigmentation was seen. CONCLUSION: The picosecond 755-nm laser is effective in the treatment of dermal pigmentary conditions in Asians with Fitzpatrick skin Types III/IV, with minimal risk of postlaser complications, and compared with the center's past experience with the Q-switched nanosecond 1064-nm laser, results in faster and more effective pigment clearance.

Branching hypopigmentation following intralesional corticosteroid injection: Case report and review of the literature.

Intralesional corticosteroid injections are frequently used to treat various musculoskeletal and dermatologic conditions, including keloid scarring. While a number of adverse events may be associated with these injections, hypopigmentation without atrophy is rare. We report a case of a pediatric patient with temporary cutaneous hypopigmentation without atrophy following intralesional corticosteroid injection in a keloid scar.

Regulation of melanocyte stem cells in the pigmentation of skin and its appendages: Biological patterning and therapeutic potentials.

Skin evolves essential appendages and indispensable types of cells that synergistically insulate the body from environmental insults. Residing in the specific regions in the skin such as epidermis, dermis and hair follicle, melanocytes perform an array of vital functions including defending the ultraviolet radiation and diversifying animal appearance. As one of the adult stem cells, melanocyte stem cells in the hair follicle bulge niche can proliferate, differentiate and keep quiescence to control and coordinate tissue homeostasis, repair and regeneration. In synchrony with hair follicle stem cells, melanocyte stem cells in the hair follicles undergo cyclic activation, degeneration and resting phases, to pigment the hairs and to preserve the stem cells. Disorder of melanocytes results in severe skin problems such as canities, vitiligo and even melanoma. Here, we compare and summarize recent discoveries about melanocyte in the skin, particularly in the hair follicle. A better understanding of the physiological and pathological regulation of melanocyte and melanocyte stem cell behaviours will help to guide the clinical applications in regenerative medicine.

Acquired disorders with hypopigmentation: A clinical approach to diagnosis and treatment.

Acquired hypopigmented skin changes are commonly encountered by dermatologists. Although hypopigmentation is often asymptomatic and benign, occasional serious and disabling conditions present with cutaneous hypopigmentation. A thorough history and physical examination, centered on disease distribution and morphologic findings, can aid in delineating the causes of acquired hypopigmented disorders. The second article in this 2-part continuing medical education series focuses on conditions with a hypopigmented phenotype. Early diagnosis and appropriate management of these disorders can improve a patient's quality of life, halt disease progression, and prevent irreversible disability.

Hypopigmented Macules as Manifestation of Lichen Planus and Lichen Planopilaris.

Lichen planus (LP) is an idiopathic inflammatory disease of the skin, hair, nails, and mucous membranes. Classic cutaneous LP is characterized by violaceous flat-topped papules that typically favor the extremities. LP on the scalp, otherwise known as lichen planopilaris, classically presents with scarring alopecia, perifollicular erythema and follicular prominence. Although LP pigmentosus presents primarily as hyperpigmentation, there is only one previous report of hypopigmented LP. In this report, the authors report 2 cases of LP that presented primarily as hypopigmented macules in 2 African American men. The first patient presented with hypopigmented macules on face and scalp as well as trunk and extremities. The second patient presented with hypopigmented macules on scalp with associated alopecia. Histopathological examination from both patients showed features of LP. The authors propose a new variant of LP that presents acutely as hypopigmented lesions.