Induction of melasma by 1064‐nm Q‐switched neodymium:yttrium–aluminum–garnet laser therapy for acquired bilateral nevus of Ota‐like macules (Hori nevus): A study on related factors in the Chinese population

Laser treatment has emerged as a common treatment modality for acquired bilateral nevus of Ota‐like macules (ABNOM). To identify the ratio of melasma induction and exacerbation before and after laser therapy for ABNOM and to observe the risk factors related to the induction and exacerbation of melasma by laser therapy, we analyzed related factors of 1268 adult Chinese patients who underwent 1064‐nm Q‐switched neodymium:yttrium–aluminum–garnet (Nd:YAG) laser (QNYL) treatment using case series and case–control studies. Overall, 24.0% of the ABNOM patients had mixed melasma. Among the ABNOM patients without melasma, after laser therapy the development of melasma was more frequently noted in patients older than 35 years (P < 0.0001), as well in patients whose ABNOM was less than 10 cm² (P = 0.027), ABNOM were light (similar to yellow‐brown) in color (P = 0.021) and skin types were closer to type IV (P < 0.0001). New melasma lesions also appeared most frequently in the zygomatic region (P < 0.0001). Among the ABNOM patients with melasma, 89.5% experienced worsening of their melasma, irrespective of their related factors above. We concluded that the risk of inducing melasma is great after 1064‐nm QNYL treatment in ABNOM patients, and particularly in the patients with both ABNOM and melasma. ABNOM patients should be treated as early as possible and before the age of 35 years.     

Evaluation of effectiveness of erbium:yttrium–aluminum–garnet laser on atrophic facial acne scars with 22‐MHz digital ultrasonography in a Turkish population

Scar formation due to acne is a common problem among the young population and significantly affects their quality of life. The aim of this study was to evaluate the efficacy of erbium:yttrium–aluminum–garnet (Er:YAG) laser resurfacing for acne scars and to objectively demonstrate the altering of collagen density in the dermis by 22‐MHz digital ultrasonography. Twenty‐one patients, aged 19–55 years, with facial acne scars were treated with Er:YAG laser. The results of the laser resurfacing were evaluated for the degree of clinical improvement, alteration of the collagen density by 22‐MHz digital ultrasonography and any adverse effects at 3 months. At 3 months after the treatment, good (in 12 patients) and near total (in four patients) clinical improvement was noted in most of the patients compared to baseline. Overall treatment results were 76% (both near total and good) in 16 patients. By ultrasonographic evaluation, the average density of dermal collagen (total density/number of patients) of 21 patients was 32.714 (right cheek) and 32.142 (left cheek) before laser facial resurfacing. At the third month after treatment, the average density of dermal collagen of 21 patients was 36.380 (right cheek) and 38.809 (left cheek). In conclusion, Er:YAG laser skin resurfacing was found to be a safe and effective treatment modality for treatment of atrophic facial acne scars. As public demand grows for less invasive modalities to approach clinical diagnosis and evaluation, digital ultrasonography seems to provide an easy and confidential method for collagen density evaluation.     

Congenital plaque‐like glomangioma treated successfully with dual wavelength pulsed‐dye and neodymium:yttrium‐aluminum‐garnet laser

Glomovenous malformations are disseminated variants of cutaneous glomus tumors. These malformations are subdivided into regional or localized, disseminated, and congenital plaque‐like forms. The congenital plaque‐like form is the rarest variant. Most treatment modalities have been disappointing in the treatment of large glomangiomas, leading to high recurrence rates. We report a case of a 34‐year‐old man with a congenital plaque‐like glomangioma on his left arm and forearm treated successfully with sequential pulsed‐dye neodymium yttrium aluminum garnet laser.     

Treatment of periorbital wrinkles with 1550‐ and 1565‐nm Er:glass fractional photothermolysis lasers: a simultaneous split‐face trial

Objective This study aimed to compare the clinical efficacies of 1550‐ and 1565‐nm Er:glass lasers in the treatment of periorbital wrinkles and to evaluate histological changes after treatment. Methods Twenty patients received five treatments each at 3‐week intervals. The right periorbital area was exposed to the 1550‐nm Er:glass laser and the left periorbital area was exposed to the 1565‐nm Er:glass laser. Clinical improvement was evaluated by two blinded physicians who assessed comparative photographs using a four‐point scale at baseline and 3 months after the final treatments. Skin biopsies were performed in five volunteers before treatment and at 3 months after the final treatment. Results The mean improvement scores 3 months after treatment with the 1550‐ and 1565‐nm Er:glass lasers were 2.25 ± 0.62 and 2.28 ± 0.59 respectively. Histological examination revealed increased epidermal thickening and decreased solar elastosis 3 months after the final laser treatments. Conclusions Both 1550‐ and 1565‐nm Er:glass lasers are safe and effective modalities in the treatment of periorbital wrinkles with no significant differences between the two lasers.     

Efficacy of 577‐nm Pro‐Yellow laser in port wine stain treatment

A port‐wine stain (PWS) is a congenital capillary malformation that is seen in 0.3–0.5% of newborns. Although many types of lasers have been used to treat PWSs, few studies have investigated the efficacy of 577‐nm Pro‐Yellow lasers. The aim of this study was to establish the efficacy of Pro‐Yellow lasers in PWS treatment. In total, 26 patients, comprising 15 females (57.7%) and 11 males (42.3%) with a mean age of 24.7 ± 11.8 (range 1–50) years were included in the study. All were treated with a 577‐nm Pro‐Yellow laser at 4‐week intervals, 3–10 times. The sessions initially used scan mode and a fluence dose of 24 J/cm² per session, on average. The mean dose was increased by 4 J/cm each session and the maximum dose administered was 44 J/cm². A mean regression of 68.8 ± 13.9% in the size of the lesions over 5.23 ± 2.7 sessions was observed. There was no statistically significant difference between the female and male patients when they were compared in terms of the number of treatment sessions (p = .789) and treatment success (p = .39). These case series demonstrate that the Pro‐Yellow laser is a safe and well‐tolerated treatment for PWSs. However, deep‐seated lesions required more treatment sessions and it was observed that clinically the lesions did not completely disappear.     

Histopathological study of the treatment of melasma lesions using a low‐fluence Q‐switched 1064‐nm neodymium:yttrium–aluminium–garnet laser

The low‐fluence 1064‐nm Q‐switched neodymium:yttrium–aluminium–garnet (QSNY) laser is a widely used treatment for melasma in East Asia, although its mechanism of action is unclear. The aim of this study was to elucidate the mechanism of action of the QSNY laser. We performed a histopathological study on eight Korean women who had considerable improvement in their melasma lesions after a series of low‐fluence QSNY laser treatments. Compared with nonlesional skin, samples from melasma lesions showed increased reactivity in melanin (Fontana–Masson staining) and in melanogenesis‐associated proteins, including α‐melanocyte‐stimulating hormone, tyrosinase, tyrosinase‐related protein (TRP)‐1, TRP–2, nerve growth factor and stem cell factor. After laser treatment, the melasma skin showed a decrease in the number of melanosomes and reduced expression of melanogenesis‐associated proteins. Expression levels of the melanogenic proteins were reduced after laser treatment, although the number of melanocytes was unchanged even in hypopigmented areas. Based on these results, we believe that repeated application of low thermal energy via QSNY laser may result in damage to melanocytes and long‐lasting hypopigmentation.     

Combined treatment with 578‐/511‐nm copper bromide laser and light‐emitting diodes for post‐laser pigmentation: a report of two cases

Postinflammatory hyperpigmentation (PIH) developing after cosmetic procedures such as lasers and chemical peels is always a concern, especially in darker skin types. We report two cases of laser‐related PIH of the face successfully treated by combined therapy with 578‐/511‐nm copper bromide laser and light‐emitting diodes (LED). Good cosmetic results were achieved in both patients. The side effects during and after treatment included a mild stinging and redness, but these were resolved within several days without any treatment. Combined 578‐/511‐nm copper bromide laser with LED provided safe and effective treatment for post‐laser pigmentation in Korean patients.     

The effectiveness of topical therapy combined with 308‐nm excimer laser on vitiligo compared to excimer laser monotherapy in pediatric patients

We evaluated the efficiency of using a 308‐nm excimer laser with either tacrolimus, pimecrolimus, or halometasone for the treatment of childhood vitiligo. Patients who received combined treatments had significantly higher rates of repigmentation in comparison with individuals who underwent excimer laser alone therapy. Moreover, patients who received treatment with excimer laser and halometasone had significantly higher rates of repigmentation, even higher than individuals who were treated with tacrolimus combined or pimecrolimus combined. This regimen was more effective on the face, neck, and limbs. We conclude that the use of a combined excimer laser and halometasone cream has a greater therapeutic effect than laser alone.     

Efficacy and safety of 1064‐nm Q‐switched Nd:YAG laser with low fluence for keloids and hypertrophic scars

Background Several treatment modalities using laser devices have been used for the treatment of keloids and hypertrophic scars with various therapeutic outcomes. Objective The purpose of this study was to describe the efficacy and safety of 1064‐nm Q‐switched (QS) Nd:YAG laser with low fluence on keloids and hypertrophic scars. Methods Keloids and hypertrophic scars located at 21 anatomic sites in 12 Korean patients (10 men and 2 women; mean age 23.8 years, range 21–33) were treated using 1064‐nm QS Nd:YAG laser with low fluence at 1–2 week intervals. Treatment settings were 1.8–2.2 J/cm², 7‐mm spot size and 5–6 passes with appropriate overlapping. Results Follow‐up data collected 3 months after the final treatment revealed decreases in the mean score for the following lesion characteristics: pigmentation from 1.8 to 1.2; vascularity from 1.4 to 1.0; pliability from 3.0 to 2.0 and height from 2.3 to 1.8. The modified Vancouver General Hospital Burn Scar Assessment score decreased from 8.6 to 5.9 (P < 0.0001). Observed side‐effects were a mild prickling sensation during treatment, and mild post‐treatment erythema, both of which resolved within few hours. Conclusion Our results demonstrate that QS Nd:YAG laser with low fluence may be used for the treatment of keloids and hypertrophic scars.     

An evaluation of the efficacy of a single‐session 577 nm pro‐yellow laser treatment in patients with postacne erythema and scarring

Erythema and scarring are among the most common complications of severe inflammatory acne. In this study, we aimed to share our experience with pro‐yellow laser and document the efficacy and safety of this treatment in postacne erythema and scarring. The study included 40 patients, 24 (60%) females, and 16 (40%) males with a mean age of 29.5 ± 8.16 (min. 18 years, max. 57 years). The pro‐yellow laser was applied to all patients as a single session with irradiation of 22 J/cm². Improvement in postacne erythema and scars were evaluated after the treatment. The study included 40 patients, 24 patients (60%) were females and 16 patients (40%) were males with the mean age of 29.5 ± 8.16 (ranged between 18 and 57 years old). A total of 21 patients (52.5%) had good improvement (51%‐75% regression), 10 patients (25%) had excellent improvement (76%‐100% regression), and a moderate improvement (26%‐50%) was detected in 9 patients (22.5%). Also, there were mild improvement (1%‐25%) in 20 patients (76.9%) and a moderate improvement (26%‐50%) in 6 patients (23.1%). We found that pro‐yellow laser is highly effective in the treatment of postacne erythema, while its effectiveness was mild to moderate in atrophic acne scars. Also, it has been observed that the pro‐yellow laser system can be used safely immediately after cessation of systemic isotretinoin treatment.