Efficacy and Safety of Long Pulsed Nd:YAG Laser in the Management of Hypertrophic Scars and Keloids

@#Keloid scars have always been a therapeutic challenge. Lasers due to their versatile action are being tried in the management of hypertrophic scars and keloid. Use of Nd:YAG laser especially in dark skin types is justifiable but sufficient data is not available.

Long-pulsed 1064 nm Nd: YAG laser combined with terbinafine against chromoblastomycosis caused by and the effect of laser therapy in a Wistar rat model / 南方医科大学学报

We report a case of chromoblastomycosis caused by , which was successfully treated by long-pulsed 1064 nm Nd: YAG laser combined with terbinafine. A 60-year-old man was admitted for the presence of a 30 mm×40 mm erythematous plaque on the dorsum of his right hand for about 10 months without any subjective symptoms. Both microscopic examination and tissue biopsy of the lesion showed characteristic sclerotic bodies of chromoblastomycosis. Lesion tissue culture on SDA at 26 ℃ for 2 weeks resulted in a black colony, and slide culture identified the isolate as Fonsecaea species. ITS sequence analysis of the isolate showed a 99% homology with strain KX078407. The susceptibility of the isolate to 9 antifungal agents was determined using the microdilution method according to the guidelines of CLSI M38-A2 protocol, and terbinafine showed the lowest MIC (0.125 μg/ml). We subsequently established a Wistar rat model of chromoblastomycosis using the clinical isolate and treated the rats with long-pulsed 1064 nm Nd: YAG laser (pulse width of 3.0 ms, fluence of 24 J/cm, spot size of 3 mm, frequency of 4 Hz, repeated 3 times at an interval of 30 s) twice a week for a total of 8 sessions. Although the laser treatment alone was not able to eliminate the fungi, histopathological examination showed the aggregation of numerous lymphocytes in the local affected tissue, indicating an immune response that consequently facilitate the regression of the lesion. The patient was successfully treated by long-pulsed 1064 nm Nd: YAG laser once a week combined with terbinafine (0.25 /bid) for 8 weeks, and follow-up for 20 months did not reveal any signs of recurrence.

Treatment of naevus of Ota with Q-switched 1064nm Nd:YAG laser

Background Naevus of Ota was first described in 1939 by Ota M. It is characterized by a bluish-gray mottled hyperpigmentation in the distribution of the trigeminal nerve. It affects between 0.014 - 0.6% of the Asian population. It is not only physically disfiguring but may be associated with tremendous psychosocial impact on the patient. The aim of the study is to determine the demographic data of local patients with naevus of Ota, their response to treatment with Q-switched 1064nm Nd:YAG laser, complications and recurrence. Materials and Methods A retrospective analysis of all patients with naevus of Ota treated with Q-switched 1064nm Nd:YAG laser between January 1998 to December 2007 was conducted at the dermatology clinic, Kuala Lumpur Hospital. Patients’ demographic data, clinical characteristics, response to Q-switched 1064nm Nd:YAG laser and the complications were reviewed. Results A total of 50 patients with naevus of Ota were treated with Q-switched 1064nm Nd:YAG laser. There were 42 female and 8 male patients with a F : M ratio of about 5:1. The mean age of presentation was 31 years old (11-60 years). More than half were Chinese patients (56%) followed by Malays (38%), Indian (2%) and others (4%). Seventy four percent of the patients had Fiztpatrick skin-type IV and the rest skin type V. Ninety two percent of the patients had unilateral trigeminal dermatomal involvement while 8% had bilateral trigeminal dermatomal involvement. Of the 15 patients who were referred to the ophthalmologist, 10 were found to have scleral involvement and none had glaucoma. Patients who had 2 treatments (13 patients) did not have any significant lightening of their lesions. In the remaining 37 patients who had 3 sessions (mean = 5.7, range 3 -15 sessions), 9 patients (24.3%) reported the response as good (51-75% lightening); 17 patients (45.3%) as excellent (>75% lightening) and 8 patients (22%) had near complete lightening (>90%). None reported any complications or recurrence. Conclusion Q-switched 1064nm Nd:YAG laser is an effective and safe treatment modality for patients with naevus of Ota.

The Effect of 1320 nm Nd: YAG Laser and Long-pulsed 1064 nm Nd: YAG Laser Irradiation on Hairless Mouse Skin / 대한피부과학회지

BACKGROUND: The treatment of facial rhytides has traditionally centered around methods that involve removal of the epidermis and superficial dermis, encouraging the production of a new epidermis with collagenesis and remodelling. But all of the resurfacing techniques lead to postoperative complications such as oozing, bleeding, infections, "downtime" as the skin begins to reepithelialize, and the occasional incidence of posttreatment, postinflammatory pigmentary changes. 1320nm and 1064nm wavelengths are nonspecifically absorbed in the human dermis and are unique for its significant horizontal scattering. These wavelengths, when used for localized facial areas, have been shown to produce new collagen formation and improvement in the quality of treated skin. OBJECTIVE: The purpose of this study was to examine the effect of 1320nm Nd: YAG laser and long-pulsed 1064nm Nd: YAG laser irradiation on hairless mouse skin and rat skin. METHODS: In this study, the effect of 1320nm Nd: YAG laser and long-pulsed 1064nm Nd: YAG laser irradiation were examined by Hematoxylin and eosin (H&E) stain, Masson's trichrome stain, immunohistochemical stain for type I collagen and dot-blot hybridization for alpha1(I) procollagen mRNA. RESULTS: In the H&E stain, Masson's trichrome stain, and immunohistochemical stain of the hairless mouse skin, the number of collagen fibers with a greater density of fibers increased, compared to the non-irradiated controls on both the 1320nm Nd: YAG laser and the long-pulsed 1064nm Nd: YAG laser. In the dot-blot hybridization in the hairless mouse, levels of alpha1(I) procollagen mRNA were increased 3.0-fold, 4.8-fold and 5.2-fold at each 1 week, 4 weeks and 12 weeks after irradiation in 1320nm Nd: YAG laser and 1.8-fold and 2.1-fold at each 4 weeks and 12 weeks after irradiation in long-pulsed 1064nm Nd: YAG laser, compared to the non-irradiated controls. But in the 1320nm Nd: YAG laser irradiation on the rat, there is no significant change in the number and density of collagen fibers, compared to the non- irradiated controls. CONCLUSION: These results indicate that the 1320nm Nd: YAG laser and the long-pulsed 1064nm Nd: YAG laser may be a powerful up-regulator of collagen synthesis through significant dermal damage and the 1320nm Nd: YAG laser is better than the long-pulsed 1064nm Nd: YAG laser for collagen synthesis. Therefore, the 1320nm Nd: YAG laser can be more effective clinically than the long-pulsed 1064nm Nd: YAG laser for the treatment of photodamaged skin.