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.     

Immediate post‐irradiation dermoscopic vascular changes versus purpura as a therapeutic endpoint in pulsed‐dye laser treatment of port wine stains

Pulsed‐dye laser (PDL) is the treatment of choice for port wine stain (PWS), and the development of purpura is considered a therapeutic endpoint. Changes in PWS vasculature observed by dermoscopy immediately after laser irradiation have been suggested to predict the minimal effective fluence. The current study aimed at comparing these changes with purpura as a therapeutic endpoint. Fifty‐six PWS patients, randomized into two groups, received five monthly PDL sessions (595 nm and 10 mm spot size). At the first visit, patients received multiple gradually increasing test irradiations. Patients in the first group were treated with the lowest dose that resulted in 24‐hr‐lasting purpura, while patients in the second group were treated with the lowest dose that resulted in vessel disappearance observed by dermoscope. No statistically significant differences were observed between the two groups (the dermoscopic and the purpuric) regarding mean average improvement (42.4 and 37.32%, respectively, p = .32), grade of improvement (p = .44), and the rate of side effects (0 and 13.79%, respectively, p = .13). In conclusion, the immediate post‐irradiation vessel disappearance (detected by dermoscope) is comparable, in safety and efficacy, to purpura as a therapeutic endpoint and maybe more time‐saving and more accepted cosmetically.     

Histological evaluation of dermal tissue remodeling with the 1444‐nm neodymium:yttrium–aluminum–garnet laser in in vivo model

Laser lipolysis has a skin tightening effect by heating the deep dermis, in addition to the removal of fat tissues. The 1444‐nm neodymium:yttrium–aluminum–garnet (Nd:YAG) laser has been expected to be more effective and safe for laser lipolysis, due to higher affinity to fat and water, than 1064‐nm and 1320‐nm wavelengths. The purpose of this study was to evaluate the skin tightening effect of the 1444‐nm Nd:YAG laser through in vivo guinea pig models. The 1444‐nm Nd:YAG laser was used to irradiate shaved dorsal skin of the guinea pigs and compared with controls (no power, only tunneling). Immediately, 1 week, 1 month and 3 months after laser administration, full‐thickness skins were harvested and to evaluate dermal thickness, collagen organization, fibroblast proliferation, and intensity of elastic fibers and mucopolysaccharides, using hematoxylin–eosin, Masson‐trichrome, Verhoeff's stain and Alcian blue stain. Dermal thickness showed an increase with time in all groups. In collagen organization, fibroblast proliferation, and intensity of elastic fibers and mucopolysaccharides, the treatment groups were higher than those of the control group, overall. Our study showed that the 1444‐nm Nd:YAG laser appeared to be effective for the skin tightening effect in in vivo guinea pig models. The 1444‐nm Nd:YAG laser can be used for skin tightening, as well as reduction of fat tissues.     

Combined pulsed dye laser and fiberoptic Nd-YAG laser for the treatment of hypertrophic port wine stain

The hypertrophic Port Wine Stain (PWS) is only partially and superficially treated with the Pulsed dye laser (PDL) because of its limited depth of penetration. We used combined PDL and fiberoptic 1444-nm Nd-YAG laser to treat a case with hypertrophic PWS. Method: After tumescent anesthesia, few holes were made by a 16-gauge needle on different sides of the lesion. The fiberoptic tip of 1444-nm Nd-YAG laser was inserted within the holes and was pushed forward while triggering. In a fan pattern and by a back and forth movement, the subcutaneous and deep dermal areas were coagulated. The skin and outer mucosal surfaces were then treated by PDL. The fiberoptic system used was Accusculpt 1444-nm Nd-YAG laser (Lutronic lasers, South Korea), and the PDL used was 585 nm Nlite system (Chromogenex UK). The parameters used for PDL were fluence = 9 Joules/cm² and the spot size was 5 mm. The parameters used for fiberoptic 1444-nm Nd-YAG laser were: Pulse rate = 30 Hz, pulse energy = 300 mJ, power = 6 W, and the total energy = 4000 J for the whole face and mucosa. Result: Little sign of regression and moderate purpura were detected immediately after combined fiberoptic Nd-YAG and PDL therapy. The lesion gradually regressed within 4 months with satisfactory color and volume change. Conclusion: Combined fiberoptic Nd-YAG laser and PDL can be used for the treatment of deeper and superficial layers of hypertrophic PWS.     

Evaluation of fluence and pulse-duration on purpuric threshold using an extended pulse pulsed-dye laser in the treatment of port wine stains

Laser therapy of port-wine stains (PWS) using the extended pulse pulsed-dye laser (EPPDL) is accepted as the optimal approach because the thermal relaxation time for the vessels in PWS is actually 1-10 msec. The purpose of this study is to elucidate the purpuric threshold using the EPPDL for treatment of PWS. One hundred and seventy-seven Japanese patients with PWS were recruited for this study. All the patients were dark-skinned with skin phototype III (n = 103) and IV (n = 74). PWS were treated with the EPPDL with a pulse duration ranging 1.5-10 msec, fluence ranging 9-15 J/cm(2), and a spot size of 7 mm. Cryogen spray cooling (CSC) was fixed to 30 msec of delay and 30 msec of spray duration. Patients returned to our clinic within 1 week after their initial laser therapy and the treatment sites were examined for the evidence of purpura formation. Of the 177 patients, 108 developed purpura. The lowest fluences that caused purpura and were seen in more than 50% of patients were 10 J/cm(2) with a pulse duration of 1.5 msec, 12 J/cm(2) with a pulse duration of 3 msec, 13 J/cm(2) with a pulse duration of 6 msec, and 13 J/cm(2) with a pulse duration of 10 msec. The fluence and pulse duration thresholds were 12.5 J/cm(2) and 1.65 msec, respectively. Because purpura is one of the treatment endpoints when using a pulsed-dye laser for PWS, higher fluences are necessary when using a long pulse duration.     

Acquired port-wine stains: A report of two cases and review of the literature

Background

Acquired port-wine stains (APWS) are rare vascular malformations that share the same clinical and histological features as their congenital counterparts. Rare cases of AWPS secondary to trauma or in association with medications have been reported in the literature.

Patients and Methods

We report two cases of APWS. One case appeared at the age of 2 months, the earliest reported in the literature and continued to evolve till the age of 3 years presenting with multifocal distribution mainly affecting the lower face. The second case developed during oral isotretinoin intake and persisted after discontinuation of the treatment.

Results and Conclusions

The second patient declined treatment, but the first patient had a remarkable improvement following treatment with the pulsed dye laser, which remains the standard of care for capillary malformations on the face.     

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.     

Efficacy of pulsed dye laser treatment of port wine stain malformations of the lower limb

BACKGROUND: There is relatively little information about treatment of port wine stains (PWS) of the lower limb. Few studies have specifically addressed the efficacy of pulsed dye laser (PDL) treatment of a PWS on the lower limb and there is no information on the relative efficacy at different sites on the lower limb. It has been suggested that treatment is not as successful when compared with the face and postinflammatory hyperpigmentation has been reported to be a significant problem. OBJECTIVES: To review retrospectively patients who attended for PDL treatment of PWS affecting the lower limb and assess the efficacy and adverse effects with particular reference to skin site. METHODS: A retrospective review was carried out of patients attending the Leeds Dermatology Laser Centre for treatment of a PWS on the lower limb with a 585-nm PDL. RESULTS: A total of 52 sites in 39 patients were treated: 17 on the thigh, 31 on the lower leg and four on the foot. The mean number of sessions per patient was 14, with an excellent outcome in seven treatment sites (13.5%), good in 13 (25%), moderate in 21 (40.4%) and poor outcome in 11 (21.1%). Patients were generally pleased with their results with a mean improvement of 7 on a scale of 0-10. Perifollicular persistence of the PWS was observed in six sites (11.5%). Adverse effects occurred in 36 patients (92.3%), most commonly hyperpigmentation (87%). Six patients (15.4%) developed atrophic scarring and four (10.3%) hypopigmentation. Atrophie blanche-like changes were seen in four patients on the lower leg. Hypertrophic scarring was not seen. CONCLUSIONS: Although physician-assessed good or excellent responses of 38.5% are lower than frequently reported for other skin sites and adverse effects may be more frequent, patient satisfaction with treatment was generally high. Patients with PWS on the lower limb merit a trial of PDL treatment.     

Photorejuvenation using long-pulsed alexandrite and long-pulsed neodymium:yttrium-aluminum-garnet lasers: a pilot study of clinical outcome and patients' satisfaction in Koreans

Long-pulsed 755-nm alexandrite and long-pulsed 1064-nm neodymium:yttrium-aluminum-garnet (Nd:YAG) lasers have been used for photorejuvenation of the face. The aim of this study was to investigate the safety and efficacy of long-pulsed alexandrite and long-pulsed Nd:YAG lasers for photorejuvenation in Korea. One hundred and sixteen Korean patients with photo-aged facial skin were enrolled. Sixty-two patients with facial pigmentation underwent long-pulsed alexandrite laser treatment. Eleven patients that wanted to improve facial pigmentation with minimal pain had quasi-long-pulsed alexandrite laser treatment. Forty three patients had long-pulsed Nd:YAG laser therapy. Outcome assessments included standard photographs and global evaluation by blinded investigators. The self-assessment grade was provided in questionnaires. Forty-four percent of patients reported excellent or good improvement of their pigmentary lesions (>50% improvement) using a long-pulsed alexandrite laser. Of patients who underwent long-pulsed Nd:YAG laser treatment, 36% reported excellent or good improvement in skin tightening, 50% in facial flushing and 45% in pigmentary lesions. We conclude that long-pulsed alexandrite and long-pulsed Nd:YAG lasers are safe and effective for facial photorejuvenation in Koreans.     

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.