Sustained Benefit After Treatment of Acne Vulgaris Using Only a Novel Combination of Long-Pulsed and Q-Switched 1064-nm Nd: YAG Lasers

The History and Advancement of Light, Lasers, and Energy-Based Devices in Dermatologic Surgery

BACKGROUND

From the theoretical foundations of laser and energy-based applications for the skin to the development of advanced medical devices, the field of dermatologic surgery has undergone transformative changes.

OBJECTIVE

To review the scientific and clinical advancement of laser and energy-based therapies within dermatologic surgery.

MATERIALS AND METHODS

A literature search was conducted to identify important scientific advancements and landmark studies on light, laser, and energy-based devices within the field of dermatologic surgery.

RESULTS

Since the introduction of selective photothermolysis principles in the 1980s, numerous laser and energy-based devices have been developed to effectively treat vascular lesions, target pigmentation, remove tattoos, rejuvenate the skin, and remove hair. Beyond aesthetic applications, photodynamic therapy was introduced to treat various neoplastic and inflammatory conditions. Lasers have also been employed to enhance transcutaneous drug delivery, and new lasers continue to emerge for treating common inflammatory conditions, such as acne. These innovations have contributed to a paradigm shift toward safe and effective, but less invasive, procedure-based treatment in addressing medical and aesthetic concerns in dermatology.

CONCLUSION

Dermatologists have consistently led the way in the continuous development and innovative application of laser and energy-based devices to effectively address a variety of skin conditions.

Treatment of Acne With a 1726 nm Laser, Air Cooling, and Real-Time Temperature Monitoring, Software-Assisted Power Adjustment to Achieve a Temperature Endpoint With Selective Sebaceous Gland Photothermolysis

OBJECTIVES

This work highlights the methods used to develop a multi-pulse 1726 nm laser system combined with bulk air-cooling for selective sebaceous gland (SG) photothermolysis using thermal imaging and software algorithms. This approach enables treating to a desired tissue temperature and depth to provide a safe, effective, reproducible, and durable treatment of acne.

METHODS

We designed and built a 1726 nm laser system with a 40 W maximum power output, a highly controlled air-cooling device, and a thermal camera in the handpiece, which permits real-time temperature monitoring of the epidermis. IRB-approved safety and efficacy trials demonstrated SG damage at depth, resulting in safe, efficacious, and durable clinical outcomes. Bioheat transfer and light transport modeling confirmed that the pulsing protocols could produce therapeutic temperatures at various SG depths, while protecting the epidermis and dermis with bulk air-cooling. Similarly, we employed clinical observations and photothermal modeling to identify pain mitigation opportunities while maintaining therapeutic efficacy. Biopsies were subsequently taken for histological evaluation.

RESULTS

Clinical and histological data, confirmed with modeling, demonstrated that multi-pulse laser delivery with bulk air-cooling selectively increased SG temperature compared to surrounding dermis and at depths unachievable by a single pulse. Subjects showed an average 71% ILC reduction at 3 months posttreatment. We identified two different pulsing protocols with similar selective photothermolysis (SP) of the SG with very different pain responses. Thus, changing the pulsing protocols allowed for pain mitigation and eliminated the need for injectable anesthetic. Histology confirmed the selective damaging of the SG at depth and the preservation of the surrounding dermis and the epidermis.

CONCLUSIONS

The multi-pulse 1726 nm laser with bulk air-cooling, thermal monitoring, treat-to-temperature (and depth) control, and a unique pulsing protocol, is capable of selectively damaging SGs at depth without damage to the surrounding dermis or the epidermis. The system offers two different protocols that were developed with different levels of discomfort allowing for two different methods for pain mitigation (injectable vs. topical anesthesia).

The PI3K-Akt-mTOR and Associated Signaling Pathways as Molecular Drivers of Immune-Mediated Inflammatory Skin Diseases: Update on Therapeutic Strategy Using Natural and Synthetic Compounds

The dysregulated phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway has been implicated in various immune-mediated inflammatory and hyperproliferative dermatoses such as acne, atopic dermatitis, alopecia, psoriasis, wounds, and vitiligo, and is associated with poor treatment outcomes. Improved comprehension of the consequences of the dysregulated PI3K/Akt/mTOR pathway in patients with inflammatory dermatoses has resulted in the development of novel therapeutic approaches. Nonetheless, more studies are necessary to validate the regulatory role of this pathway and to create more effective preventive and treatment methods for a wide range of inflammatory skin diseases. Several studies have revealed that certain natural products and synthetic compounds can obstruct the expression/activity of PI3K/Akt/mTOR, underscoring their potential in managing common and persistent skin inflammatory disorders. This review summarizes recent advances in understanding the role of the activated PI3K/Akt/mTOR pathway and associated components in immune-mediated inflammatory dermatoses and discusses the potential of bioactive natural products, synthetic scaffolds, and biologic agents in their prevention and treatment. However, further research is necessary to validate the regulatory role of this pathway and develop more effective therapies for inflammatory skin disorders.

Long‐pulsed Nd: YAG laser (1064 nm) versus intralesional botulinum toxin type (A) in acne vulgaris therapy: a split face study

BACKGROUND

Acne can be considered more than a cosmetic concern due to its large impact on patients' quality of life. There are various therapeutic options for inflammatory acne, but inconvenience and undesirable side effects prompted a search for more acceptable treatments. This study aimed to compare the clinical efficacy and safety of long-pulsed Nd: YAG laser 1064 nm versus intralesional botulinum toxin type-A (BTX-A) in inflammatory acne therapy.

METHODS

A prospective randomized split-face comparative study involved 30 patients with inflammatory acne. Each patient received long-pulsed Nd: YAG 1064 nm laser on one side, and intralesional BTX-A on the other side, monthly until improvement or maximum three sessions. Cases were assessed by acne lesions counting and grading of severity by Investigator's Global Assessment of acne (IGAs) at baseline, each session, and after 3 months follow-up.

RESULTS

A highly statistically significant improvement in lesions count and IGAs for both sides was observed, with statistically non-significant difference between both sides at end of treatment sessions. While, after 3 months follow-up, there was a more significant improvement at laser side.

CONCLUSION

Both long-pulsed Nd: YAG laser 1064 nm and intralesional BTX-A are safe and effective for acne therapy. Nd-YAG laser has a more prolonged efficacy and lower recurrence rate than intralesional BTX-A.

Intense Pulsed Light Therapy Improves Acne-Induced Post-inflammatory Erythema and Hyperpigmentation: A Retrospective Study in Chinese Patients

Introduction

Post-inflammatory erythema (PIE) and post-inflammatory hyperpigmentation (PIH) are the most common acne-related sequelae with no effective treatments. By combining different cut-off filters, intense pulsed light (IPL) therapy can effectively treat these conditions with few side effects. While the safety and effectiveness of IPL for treating post-burn hyperpigmentation is well known, there is little evidence for its benefits for acne-related PIH. In this article, we evaluate the efficacy and safety of IPL for the treatment of acne-related PIE and PIH.

Methods

This retrospective study evaluated 60 patients with more than 6 months of PIE and PIH treated by the same IPL device and similar protocols. The treatment included three to seven sessions at 4–6-week intervals, and three cut-off filters (640 nm, 590 nm and 560 nm) were used sequentially in each session. Using the Global Aesthetic Improvement Scale (GAIS), Cardiff Acne Disability Index (CADI), and Erythema Assessment Scale (EAS), patients were evaluated on the basis of their facial photographs. The facial brown spots and red areas were visualised and analysed using the VISIA-CR system. Six months after the last treatment, the patients were assessed for acne relapse or any side effects.Please check and confirm that the authors and their respective affiliations have been correctly processed and amend if necessary.Checked and confirmed. No further corrections.

Results

On the basis of the GAIS, 49 of 60 patients (81.7%) showed complete or partial clearance of erythema and hyperpigmentation. The CADI and EAS scores showed significant improvement (p < 0.01) after IPL treatment compared with pre-treatment. A significant reduction (p < 0.01) in the facial brown spots and red areas was seen after IPL treatment. While no long-term side effects were reported, seven patients (11.7%) experienced acne relapse at follow-up.

Conclusion

IPL is an effective and safe treatment for acne-related PIE and PIH.

The Use of Lasers and Light Devices in Acne Management: An Update

Acne vulgaris is a disease of the pilosebaceous unit and the most common inflammatory dermatosis worldwide. It is also associated with significant economic burden. Limitations of conventional topical and systemic treatments include long treatment course, intolerable adverse effects, antibiotic resistance, and patient compliance. Therefore, laser and light-based interventions present as alternative options over the past decade and have been used in combination with conventional pharmacological therapies and other physical modalities. An updated overview on the use of lasers and light-based devices in acne management is presented to help clinicians understand the safety and efficacy of these treatment options. The effectiveness of neodymium:yttrium aluminum garnet (Nd:YAG) for treating acne is supported by more high-level studies compared with other laser devices. There is limited evidence to support the use of CO₂ lasers, potassium titanyl phosphate lasers, and 1565-nm non-ablative fractional lasers for treating acne. Among light devices, photodynamic therapy is the most studied, showing higher efficacies than some of the conventional topical and oral acne therapies. Intense-pulsed light and blue light therapies also show favorable outcomes. A limitation is that most studies are non-randomized and lack a control group, and report on a variety of device settings, treatment regimens, and outcome measures, making it challenging to summarize and generalize findings. Although the use of laser and light devices to treat acne is promising, further work with randomized controlled study designs and larger sample sizes will provide improved guidance on the application of these modalities.

Quasi long-pulsed 1064nm Nd:YAG (micro pulsed) technology for the treatment of active acne: A case series

BACKGROUND

Acne vulgaris is common dermatologic condition with an estimated prevalence of 80%. Acne has been shown to have a significant impact on patient quality of life and mental health, especially as inflammatory lesions typically occur on cosmetically sensitive areas with the potential for permanent scarring. There have been numerous advances in the treatment of inflammatory acne with light-based and laser devices. This technology permits effective treatment of active acne and scarring, with a short recovery and a decreased side effect profile as compared to medicinal standard-of-care and photodynamic therapies.

OBJECTIVE

The case series study was aimed at evaluating the safety and efficacy of a 1064 nm Nd: YAG Quasi-longed pulse laser treatment for acne vulgaris.

METHODS

This was a prospective study of 19 subjects with moderate to severe. All subjects received 1064 nm Nd: YAG Quasi-longed pulse laser treatments, at 8 J/cm² fluence and accumulated 1000-4000 kJ according to treatment area at two weeks intervals. Primary end point was reaching a minimal AGSS score of between 1 and 2. Acne severity was assessed by two independent dermatologists according to AGSS scale before each treatment session and at the follow-up visit (8 weeks following last treatment). Subjects' self-assessment of Patient Global Impression of Change (PGIC) and overall satisfaction were also recorded. Safety was assessed by recording pain, adverse events, and downtime throughout the trial.

RESULTS

Investigator's US FDA AGSS scoring of acne appearance improvement shows an average of 6.6 treatments were required to reach the minimal AGSS score endpoint. Significant reduction in AGSS scores was recorded after 2 treatments (4.21 ± 0.65 vs 3.05 ± 0.83 p = 1.63E^-05 ), and maintained a statistically significant reduction rate throughout the trial. Minimal AGSS scores were still detected after 8 weeks following final treatment. Subjects scored high satisfaction rates and PGIC scores (2.9 and 5.3, respectively). Some patients reported transient erythema as only adverse events recorded in the study.

CONCLUSION

The 1064 nm Nd: YAG Quasi-longed pulse laser was found to be safe and highly effective for the treatment of facial acne. The treatments were well tolerated, and the subjects experienced no pain and no downtime. Light-based treatments do and will probably continue to play an important and enlarging role in acne management.

Efficacy and safety of intense pulsed light using a dual-band filter for the treatment of facial acne vulgaris

Intense pulsed light (IPL) devices have been used in acne treatment in combination with conventional topical and oral medications. This study aimed to evaluate the efficacy and safety of IPL treatment using a dual-band filter (400-600 nm and 800-1200 nm) in facial acne vulgaris treatment. Twenty-three acne vulgaris patients were enrolled in this study. The patients were treated on both sides of the face. The treatments were performed in 2-week intervals for a total of five sessions. The final visit for the clinical evaluation was 2 weeks after the fifth treatment session. The mean number of papules, pustules, and comedones, and the melanin index, was significantly decreased at the final visit. However, sebum production and the erythema index showed no statistically significant differences after treatment. IPL treatment using a dual-band filter can be an alternative for patients who are unfit for systemic acne medication. It can also be used with conventional acne treatment for better treatment results.

650 usec 1064nm Nd:YAG laser treatment of acne: A double-blind randomized control study

BACKGROUND

A variety of energy-based devices have been used to treat acne. However, all studies have been subjective and have not involved double-blind and randomized controlled studies.

AIMS

We undertook a randomized controlled study evaluating the use of a 650 usec 1064 nm Nd:YAG laser compared with a sham in the treatment of acne.

PATIENTS/METHODS

A total of 20 subjects with moderate-to-severe acne were randomized to receive either 650 usec 1064nm Nd:YAG laser or sham treatment. All subjects received 3 treatments, two weeks apart, plus an additional session undertaken 4 weeks after the 3rd treatment. Subjects were evaluated for investigator global improvement, improvement in inflammatory lesions, improvement in comedonal lesions, total porphyrin score, and total sebum score.

RESULTS

The laser-treated group showed an Investigator's Global Assessment Scale (IGA) improvement of 26% compared with 7% for the sham group (a 271% improvement over sham treatment group). The treatment group also showed a decrease in the number of inflammatory lesions of 42% compared with 26% in the sham group (a 62% improvement over sham). The laser-treated cohort also experienced a reduction in total number of comedones similar to that seen with inflammatory lesions and a decrease in total porphyrin score. There was also an 18% reduction in sebum production in the treated group, compared with 9% in the sham group (a 100% improvement).

CONCLUSION

This is the first study that has compared laser treatment of acne compared with a sham treatment. A 650 usec 1064nm Nd:YAG laser can effectively treat acne.