Comparison of effectiveness of 1,064-nm Nd:YAG laser and Nd:YAG laser-IPL combination treatments in hand skin rejuvenation.

OBJECTIVE: Evaluation of the efficacy and side effects of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser and Nd:YAG laser-intense pulsed light (IPL) combination treatments in photorejuvenations of skin of the hand, and determining their impacts on patient satisfaction. MATERIALS AND METHODS: Thirty-five female patients with signs of photoaging on the skin of their hands were included in the study. Three sessions of IPL and four sessions of Nd:YAG laser treatment were applied to the right hand in total with 2-week intervals between each session, whereas six sessions of Nd:YAG laser treatment were applied to the left hand of patients with 2-week intervals between each session. RESULTS: The patients' ages ranged between 31 and 78, and mean age was 60.77 ± 9.48. While there was no difference in pigment distribution, fine wrinkles, coarse wrinkles, and global scores between the right and left hand prior to treatment (p > 0.05), average pigment tone score was higher in the right hand with a statistically significant difference (p < 0.05). There was greater improvement in scores of pigment distribution, fine wrinkles, sallowness, pigment tone parameters, and global score on the right hand compared to left hand, which was statistically significant (p <0.001). CONCLUSION: In rejuvenation of photoaged dorsal skin of the hand, IPL-Nd:YAG laser combination treatment surpasses Nd:YAG laser treatment.

Influence of the frequency of laser toning for melasma on occurrence of leukoderma and its early detection by ultraviolet imaging.

BACKGROUND AND OBJECTIVE: Laser "toning" with a Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser has recently been described to be effective for the treatment of melasma. Leukoderma is a refractory complication of laser toning for melasma, but it can be detected early with ultraviolet (UV) imaging. We assessed the relationship between leukoderma and the frequency or total number of laser toning sessions, as well as the effectiveness of UV imaging for detecting leukoderma. MATERIALS AND METHODS: The subjects included 147 patients who received at least five laser toning sessions. Subjects were classified into three groups according to the frequency of treatment (weekly for Group A1, fortnightly for Group A2, and monthly for Group B), and the incidence of leukoderma was compared among the three groups. In patients who developed leukoderma, the interval between clinical diagnosis and leukoderma detection on UV images (obtained with a Visia Evolution during every laser toning session) was determined to evaluate the effectiveness of UV imaging for the early detection of leukoderma. RESULTS: The overall incidence of leukoderma was 2% (3/147 patients): 3.8% (1/26 patients) in Group A1, 4% (2/49 patients) in Group A2, and 0% (0/72 patients) in Group B. There were no significant differences in the incidence of leukoderma relative to the frequency of laser toning. In two of the three patients who developed leukoderma, it was diagnosed clinically at the 20th and 21st laser toning session, whereas it was diagnosed by UV imaging at the 12th and 13th session. In the remaining 1 patient, leukoderma was detected clinically and by UV imaging at the 7th session. CONCLUSIONS: There was no significant difference in the incidence of leukoderma related to the frequency of laser toning. This study showed that there are two types of leukoderma associated with laser toning. UV imaging was effective for the early detection of type 1 leukoderma, which seems to be related to the cumulative laser energy delivered, but not for detecting type 2 leukoderma, which may be due to direct phototoxicity.

Case Study of Onychomycosis Patients Treated with 1,064-nm Nd:YAG Laser.

Onychomycosis is the most frequent nail disease, with an estimated prevalence of 2-8%. Current treatment strategies include the use of oral and topical antifungals, despite low cure rates following these treatments. The objectives of this study were to assess the therapeutic response of patients with onychomycosis to 1,064-nm Nd:YAG laser treatment, the clinical evaluation method available for this therapy, and the possible side effects of this treatment. Twenty patients with onychomycosis underwent laser therapy. A total of 34 nails with onychomycosis were assessed according to the Onychomycosis Severity Index (OSI). This index generates scores that classify onychomycosis as mild, moderate, or severe. The OSI was determined before treatment and after a mean follow-up period of 8 months. The comparison between the initial and the final OSI for all 34 nails treated with laser therapy showed a significant difference; however, a low association was shown between these variables. A general reduction in the area of involvement and in the OSI numerical scores was observed. These data show a trend toward improvement in onychomycosis treated with 1,064-nm Nd:YAG laser. The OSI allowed an adequate clinical assessment of the response to laser therapy. Laser treatment did not cause marked discomfort in most patients, indicating that laser is a well-tolerated procedure.

Analysis of epidermal/dermal temperature changes according to the different cryogen spray cooling conditions.

This study measured epidermal and dermal temperatures under different cryogen spray cooling (CSC) conditions to determine the optimum cooling conditions for skin rejuvenation. For this purpose, CSC conditions were applied before a laser transmission for varying spurt times of 50, 150, and 200 ms with delay times of 150 and 200 ms. A long-pulsed 1,064 nm Nd:YAG laser irradiated the skin surface of a pig with a condition of fluence of 26 J/cm2 and a spot diameter of 8 mm. The pulse duration was set to 30 ms during all experiments. This study found that all employed CSC conditions significantly decreased internal-external skin temperatures. Moreover, skin temperatures were influenced more by variations in spurt time of CSC compared with the delay times. Based on these experimental results, two spurt times were selected as the optimum CSC conditions for skin rejuvenation: 50 ms with delay time of 150 and 200 ms and 150 ms with a delay time of 150 and 200 ms.

Analysis of epidermal/dermal temperature changes according to the different cryogen spray cooling conditions.

This study measured epidermal and dermal temperatures under different cryogen spray cooling (CSC) conditions to determine the optimum cooling conditions for skin rejuvenation. For this purpose, CSC conditions were applied before a laser transmission for varying spurt times of 50, 150, and 200 ms with delay times of 150 and 200 ms. A long-pulsed 1,064 nm Nd:YAG laser irradiated the skin surface of a pig with a condition of fluence of 26 J/cm2 and a spot diameter of 8 mm. The pulse duration was set to 30 ms during all experiments. This study found that all employed CSC conditions significantly decreased internal-external skin temperatures. Moreover, skin temperatures were influenced more by variations in spurt time of CSC compared with the delay times. Based on these experimental results, two spurt times were selected as the optimum CSC conditions for skin rejuvenation: 50 ms with delay time of 150 and 200 ms and 150 ms with a delay time of 150 and 200 ms.