The role of mast cells in non-ablative laser resurfacing with 1,320 nm neodymium:yttrium–aluminium–garnet laser

Multiple microneedling sessions for minimally invasive facial rejuvenation: an objective assessment

BACKGROUND

Microneedling or percutaneous collagen induction is a new modality used for skin rejuvenation, tightening, and scar remodeling. It offers a simple and effective treatment for photoaged skin with minimal disruption of the epidermis, thus limiting adverse effects and minimizing downtime.

OBJECTIVES

To evaluate the efficacy, coupled with quantitative assessment, of the histological changes in response to multiple sessions of skin microneedling in the treatment of aging skin.

PATIENTS AND METHODS

Ten patients with Fitzpatrick skin type III and IV and Glogau class II to III wrinkles were subjected to six skin microneedling sessions at 2-week intervals. Standard photographs and skin biopsy specimens were obtained at baseline and at one and three months after the start of treatment. Histometry for epidermal thickness and quantitative evaluation of collagen types I, III, and VII, newly synthesized collagen, total elastin, and tropoelastin were performed for all skin biopsies.

RESULTS

Skin microneedling produced noticeable clinical improvement of photoaged skin, with corresponding histological enhancement. Compared to the baseline, collagen types I, III, and VII, as well as newly synthesized collagen, together with tropoelastin showed a statistically significant increase (P < 0.05) in response to treatment, while the mean level of total elastin was significantly decreased (P < 0.05) after treatment.

CONCLUSIONS

Skin microneedling is a promising minimally invasive treatment option with the advantage of increased collagen production. However, multiple sessions are usually needed to maintain the improvement achieved.

Expression of transforming growth factor-β after different non-invasive facial rejuvenation modalities

BACKGROUND

Transforming growth factor-β (TGF-β) is a major regulator of the synthesis of extracellular matrix (ECM) proteins in human skin as it stimulates fibroblast proliferation and collagen production. Perturbed TGF-β expression may play a key role in the pathogenesis of skin aging.

OBJECTIVES

This study was conducted to objectively evaluate the effects of different modalities of non-invasive facial rejuvenation on TGF-β expression and to correlate its level with that of newly synthesized collagen.

METHODS

A total of 36 patients with Fitzpatrick skin types III and IV were divided into six groups. Each group of six patients was subjected to a different non-invasive modality for the treatment of skin aging, including radiofrequency (RF), Nd:YAG 1320-nm laser and Er:YAG 2940-nm laser mini-peels, intense pulsed light (IPL), mesotherapy injection, and electro-optical synergy (ELOS). Skin biopsies were obtained before treatment, at the end of treatment, and at three months post-treatment. In addition, biopsies were obtained from 30 control subjects. Levels of TGF-β were quantitatively evaluated using computerized image analysis of immunostained sections.

RESULTS

The expression of TGF-β was statistically significantly increased (P < 0.05) at the end of Nd:YAG 1320-nm and Er:YAG 2940-nm mini-peel treatments compared with baseline levels, and at three months post-treatment with RF and ELOS compared with pretreatment and end-of-treatment levels. However, no significant differences (P > 0.05) were observed in TGF-β level in response to IPL or mesotherapy treatments in comparison with baseline. The level of TGF-β was positively correlated (P < 0.05) to that of newly synthesized collagen at the end of Nd:YAG 1320-nm laser and Er:YAG 2940-nm laser mini-peels, as well as at three months after RF and ELOS treatments.

CONCLUSIONS

Radiofrequency, ELOS, and Nd:YAG 1320-nm laser and Er:YAG 2940-nm laser mini-peels resulted in an increase in TGF-β expression, which may mediate the effects of these modalities in enhancing dermal collagen expression through the activation of fibroblasts and thereby reverse the photoaging of skin.

Expression of p53 protein after nonablative rejuvenation: the other side of the coin

BACKGROUND

Disturbance of p53 expression may play an important role in the pathogenesis of ultraviolet (UV) light-induced skin cancer as well as photoaging.

OBJECTIVES

To objectively evaluate the potential effect of nonablative facial rejuvenation on p53 expression.

PARTICIPANTS AND METHODS

Thirty patients with Fitzpatrick skin type III to IV were divided into five groups. Each group underwent a different nonablative modality: radiofrequency (RF), intense pulsed light (IPL), electro-optical synergy (ELOS) (combined RF and IPL), 1,320-nm neodymium-doped yttrium aluminum garnet (Nd:YAG) laser, and 2,940-nm erbium-doped (Er):YAG laser minipeel. Skin biopsies were obtained before treatment, by the end of treatment, and 3 months after treatment. Biopsies were also taken from 30 controls. Quantitative evaluation of p53 was performed using computer image analysis for immunostained tissues.

RESULTS

P53 expression was statistically significantly greater at the end of IPL (p = .02) and ELOS (p = .02) treatments than before treatment but was statistically insignificantly lower (p > .05) 3 months after treatment than at the end of treatment. No significant differences (p > .05) were observed in p53 level after RF, 1,320-nm Nd:YAG, and 2,940-nm Er:YAG mini-peel treatments from baseline.

CONCLUSIONS

The increase in epidermal p53 expression after IPL treatment could increase the risk of skin neoplasia by intense pulsed light-induced DNA damage which may lead to dysregulation of apoptosis and initiation of skin cancer.

Multiple minimally invasive Erbium: Yttrium Aluminum Garnet laser mini-peels for skin rejuvenation: an objective assessment

BACKGROUND

As the demand for minimally invasive rejuvenation is increasing, micropeel resurfacing using Erbium:Yttrium Aluminum Garnet (Er:YAG) laser 2940 nm has been reported for the treatment of photoaged skin without ablation of the epidermis. However, little is known about the efficacy and underlying histologic changes associated with this type of treatment.

AIMS

The aims of this study are to evaluate the clinical effect and objectively quantify the histological changes in response to multiple sessions of Er:YAG laser 2940 nm mini-peels.

PATIENTS AND METHODS

Six female volunteers of Fitzpatrick skin type III-IV and Glogau's class I-III wrinkles were subjected to six microresurfacing peels at 2-week intervals using Er:YAG 2940 nm laser at subablative fluences of 2-3 J/cm(2) to treat periorbital rhytides. Quantitative evaluation of collagen types I, III, and VII, newly synthesized collagen, total elastin, and tropoelastin was performed by histochemistry and immunohistochemistry coupled with computerized morphometric analysis at base line, end of treatment, and 3 months post-treatment.

RESULTS

Compared to the base line, evaluation of volunteers revealed obvious clinical improvement in response to Er:YAG mini-peels. Collagen types I, III, and VII, as well as newly synthesized collagen, together with tropoelastin showed a statistically significant increase in response to treatment, while the mean level of total elastin was significantly decreased in response to treatment. However, this was followed by regression of improvement at 3 months post-treatment but was still better than baseline.

CONCLUSIONS

This study revealed that multiple Er:YAG mini-peels is a promising treatment option for photoaging as it reverses the signs of photoaged skin with little downtime and side effects. However, to maintain the short-term improvement achieved after treatment, continued Er:YAG 2940 nm laser mini-peels is required.

Effects of the Nd:YAG 1320-nm laser on skin rejuvenation: clinical and histological correlations

The neodymium:yttrium-aluminum-garnet (Nd:YAG) laser is a popular non-ablative treatment used for skin rejuvenation. The purpose of this prospective study was to evaluate the clinical effects, coupled with a quantitative assessment, of the histological changes in response to Nd:YAG 1320-nm laser treatment of periocular wrinkles. Six volunteers with Fitzpatrick skin types III and IV and Glogau class I-II wrinkles were subjected to 3 months of Nd:YAG 1320-nm treatment in the periocular area (six sessions at 2-week intervals). Volunteers were photographed, and skin biopsies were obtained at baseline as well as 3 and 6 months after the start of treatments. Quantitative evaluation of total elastin, newly synthesized tropoelastin, collagen types I, III and VII, and newly synthesized collagen was performed using a computerized morphometric analysis. A noticeable clinical and histological improvement was observed after Nd:YAG 1320-nm treatment. Collagen types I, III and VII, as well as newly synthesized collagen, together with tropoelastin showed a statistically significant increase in response to treatment, while the mean level of total elastin was significantly decreased after treatment. Our data suggest that Nd:YAG 1320 nm is an effective treatment for skin rejuvenation as it stimulates the repair processes, and reverses the clinical, as well as the histopathological, signs of skin aging.

Neck skin rejuvenation: histological and clinical changes after combined therapy with a fractional non-ablative laser and stabilized hyaluronic acid-based gel of non-animal origin

BACKGROUND

The laser Affirm™ (LA) is a microthermal, non-ablative fractional laser used for skin rejuvenation. Restylane Vital™ Light (RVL) in the Restylane® Injector, a formulation of stabilized hyaluronic acid-based gel of non-animal origin, is indicated for rejuvenation of delicate skin.

OBJECTIVES

To assess the interaction between the LA and RVL in aging skin of the neck using clinical and histological parameters, and to determine whether combined therapy is effective.

METHODS

Nine female patients aged 42-62 years received four treatments, each comprising RVL followed immediately by LA treatment. Photographs and skin biopsies were taken before treatment, after the fourth session and 1 month later.

RESULTS

Improvements in fine wrinkles, tightness and skin texture were observed. Histologic evaluations showed favourable changes in cellularity, collagen and elastic fibres. Laser-induced effects (400 μm) and an inflammatory reaction (1000 μm) were seen. RVL was present at the mid-deep dermis (1000-1500 μm).

CONCLUSIONS

Combined treatment with the LA and RVL improved skin appearance and structure as assessed, for the first time, with histology. The LA produced epidermal and superficial dermal changes whereas RVL acted deeper, together treating the full skin thickness.