Latest laser and light-based advances for ethnic skin rejuvenation

Acute exposure of 532 nm laser differentially regulates skin tissue transcription factors

High energy laser, particularly 532 nm, is widely used in defense and medical applications and there is need to address its occupational safety. Thermal and non-thermal effects of 532 nm high energy laser on skin are cause of concern. This study indicates impact of 532 nm laser on rat skin and first of its kind of attempt to understand transcriptional activation of genes as an early response following laser exposure. Skin of experimental rats were exposed to 532 nm radiance at 0.1, 0.25 and 0.50 W/cm2 for 10 sec. Thermographic changes of skin exposed to 532 nm laser exhibited increased Tmax temperature in radiance dependent manner. After thermal imaging, skin of experimental rats was collected 1 h post laser exposure for studying differential gene expression. The skin exposed to lower power density (0.1 W/cm2) did not show significant changes in expression of gene pathways studied. At moderate radiance (0.25 W/cm2), predominantly canonical wnt/B-catenin pathway genes notch1, axin2, ccdn1, wnt5a and redox homeostasis genes; txn1, nqo1 and txnrd1 were expressed. At higher radiance (0.5 W/cm2), significant repression of genes related to wound healing process particularly notch/wnt pathway viz. hes5, wnt1, wn3b with higher expression of dab2 was recorded. The data obtained from these studies would help in drawing safety limits for skin exposure to 532 nm laser. Further, genes expressed at moderate and high level of radiance exposure to skin were distinct and differential and provide new avenue to configure pathway to counteract laser induced delay in tissue injury and hair follicular damage.

Laser Skin Rejuvenation With Fractional 1064 Q-switched Nd:YAG In 252 Patients: An Indian Experience

OBJECTIVE

The objective of our study was to present the results and safety profile of fractional 1064 Q-switched Nd: YAG laser treatment in skin rejuvenation in Indian patients with Fitzpatrick skin type III-VI.

MATERIALS AND METHODS

We studied our clinical data of 252 patients who underwent treatment for facial skin rejuvenation with the Q switched Nd:YAG laser 1064 wavelength, using the fractional mode of 5mm spot size with fluences from 1.2 J ~ 2 J/cm² and the energy ranging from 300-500 mJ, a repetition rate of 7Hz and pulse duration of 8 ns for 6 sessions at two weekly intervals. We evaluated results with the aid of clinical photography taken before start of treatment, on 3rd and 5th sessions along with patient satisfaction and dermatologist assessment scores. Any adverse events were also recorded.

RESULTS

At the end of 6 sessions, both patients and dermatologists reported visible improvement in skin texture and tone. The laser sessions resulted in an immediate improvement in skin texture and tone in the first session itself that increased over 3 sessions and then stabilized. Transient erythema was reported in a few cases. No hypo- or hyperpigmentation were noted.

CONCLUSIONS

The 1064 QSNYL is popularly used for skin rejuvenation especially in the Asian countries. But there is lack of substantial clinical data to validate the clinical results. We present the first study that shows the fractional 1064 Qswitched ND:YAG laser is a safe and effective option for skin rejuvenation in skin types III-VI.

Laser Resurfacing for Latin Skins: The Experience with 665 Cases

BACKGROUND

CO2 resurfacing and CO2 microfractionated laser systems are reliable tools to improve different facial pathologic skin conditions but are associated with a high rate of complications specially in Fitzpatrick III, IV, and V skin phototypes, predominant in the Latin population, which has pushed many surgeons to change technologies and abandon its use.

OBJECTIVE

To compare patient results with the CO2 resurfacing laser and microfractionated CO2 laser resurfacing in all skin types and show similar results to those obtained worldwide in patients with phototypes III, IV, and V.

METHODS

Standardized review of medical records from a database of private practice patients treated since January 1998 to July 2012 with SlimE30 MiXto SX(®) CO2 laser. Evaluation of outcomes, complications, and satisfaction of three different modalities of treatment (CO2 ablative laser, CO2 microfractionated and a combination of both) was made.

RESULTS

A total of 665 treated patients were included. Ablative CO2 was applied to 80.3 %, CO2 microfractionated to 15.1 %, and mixed treatment to 4.5 % of cases. Globally, hyperpigmentation rates were 30.4 % in the CO2 resurfacing group, 16.3 % when a combination of modalities was applied and 11 % in microfractionated CO2 cases. A steady increase of these rates is shown as the phototype becomes higher. Satisfaction rates were high for all groups: 86.7 % in the mixed group, 82.2 % in the microfractionated CO2, and 79.6 % in the CO2 ablative.

CONCLUSIONS

Good results and an acceptable rate of complications in latin skins are obtainable after treating patients with CO2 ablative and microfractionated CO2 systems alone or in combination. Staged treatments and adequate post-procedure care reduce these complications.