Wound Healing Treatments After Ablative Laser Skin Resurfacing: A Review.

Laser resurfacing has progressed since the 1980s to treat a variety of medical and aesthetic indications with ever-evolving safety parameters. While laser technology has evolved to provide a more favorable safety profile and decrease wound healing time, advances in post-procedure healing agents have also helped to mitigate adverse effects, such as persistent erythema, dyspigmentation, acneiform eruptions, dermatitis, infections, and scarring. We reviewed the evidence of growth factors, stem cells, silicone and silicone polymers, botanical based treatments, fatty acids, probiotics, and closed dressings on post-ablative laser skin resurfacing. All reviewed agents demonstrated some evidence in improving post-procedure outcomes, albeit mixed in many cases. Additionally, these studies contain small numbers of participants, vary in type, strength, and clinical indication for which the resurfacing laser was used, and have differing postprocedural evaluation protocols and assessments. This highlights a need for standardization of clinical studies and the importance of choosing an optimal postprocedural skincare plan depending on every unique clinical scenario. J Drugs Dermatol. 2020;19(11):1050-1055. doi:10.36849/JDD.2020.5386.

Pilot Study to Demonstrate Improvement in Skin Tone and Texture by Treatment with a 1064 nm Q-Switched Neodymium-Doped Yttrium Aluminum Garnet Laser.

BACKGROUND: The 1064 nm Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG) laser was developed to treat unwanted pigmentation in the skin such as lentigines caused by photoaging, and tattoos from dye/ink insertion. This laser has also been used for non-ablative epidermal rejuvenation (skin toning). OBJECTIVE: To evaluate changes in skin tone, skin texture and overall improvement after a series of treatments with the QS Nd:YAG laser. METHODS: Participants received seven full-face treatments with M22 or Stellar M22, a 1064 nm QS Nd:YAG laser, at 2-week intervals. The investigators and participants evaluated the improvement in skin tone and texture at 1, 3 and 6 months after the last treatment. Patient satisfaction, patient discomfort, downtime and adverse events were recorded. Histological changes in the treated area were also evaluated. RESULTS: Thirteen women with a median age of 45 years (range, 34-61 years) were included in the study. The majority of the participants (53.9%) had skin type VI. One month after the last treatment session, 38% of participants reported good to very good improvement. This value increased to 100% participant improvement at both the 3-month and 6-month follow-up visits. The reduction in melanin index and the histological analysis demonstrated that the laser procedure contributed to a reduction in epidermal melanin content. Treatments were not associated with high levels of pain or discomfort. The most common immediate post-treatment response was erythema and edema. Most participants were satisfied with the resulting treatment outcome. CONCLUSION: Skin treatment with the 1064 nm QS Nd:YAG laser module on the M22 and Stellar M22 devices, using a large spot size, low fluence, moderately high repetition rate, improves skin tone and texture in patients with skin types II-VI.

The effect of a dual-wavelength 532 nm and 1064 nm picosecond-domain laser with a fractionated holographic optic on photoaging and patient age perception: A pilot study.

INTRODUCTION: This study evaluated the efficacy of a dual-wavelength 532 nm/1064 nm Nd:YAG picosecond-domain laser with a holographic lens array in treating facial photoaging. METHODS: Thirteen subjects were enrolled with 10 completing the study. Receiving three-month treatments, subjects underwent full-face spot treatment of facial lentigines with the 532-nm non-fractionated handpiece, followed by two sequential facial passes of the 1064-nm and the 532-nm fractionated handpieces. Improvement was measured by treating physician evaluation of pigmentation and rhytids as well as blinded reviewer evaluation of pre- and post-treatment image sets taken 12 weeks after the final treatment. Participants completed treatment surveys to assess satisfaction. RESULTS: Physician grading on a 5-point scale revealed an average improvement of 1.6 in pigmentation (p = 0.0042) and 0.9 in rhytids (p = 0.0196). Blinded physicians appropriately selected baseline images in 44 of 50 (88%) image sets (10 subjects; five reviewers). On an 11-point scale for overall facial photoaging (0 = no change, 1 = 10% improvement, 2 = 20% improvement, etc.) treating physicians scored mean improvement as 3.3 ± 1.83 (95% CI 1.99 to 4.61; range 1-6), while blinded reviewers scored mean improvement as 2.32 ± 2.62 (range % -4 to 8, 95% CI 1.57 to 3.07). The greatest majority (80%) of participants reported satisfaction with the treatment. Adverse events were mild; however, one patient developed hyperpigmentation, consistent with melasma that was successfully treated with topical agents. CONCLUSION: This is the first study to show that picosecond-domain 532 nm/1064 nm laser treatments with combination non-fractionated and fractionated handpieces are well-tolerated, safe, and effective for the treatment of photodamage.

Subdividing Y-chromosome haplogroup R1a1 reveals Norse Viking dispersal lineages in Britain.

The influence of Viking-Age migrants to the British Isles is obvious in archaeological and place-names evidence, but their demographic impact has been unclear. Autosomal genetic analyses support Norse Viking contributions to parts of Britain, but show no signal corresponding to the Danelaw, the region under Scandinavian administrative control from the ninth to eleventh centuries. Y-chromosome haplogroup R1a1 has been considered as a possible marker for Viking migrations because of its high frequency in peninsular Scandinavia (Norway and Sweden). Here we select ten Y-SNPs to discriminate informatively among hg R1a1 sub-haplogroups in Europe, analyse these in 619 hg R1a1 Y chromosomes including 163 from the British Isles, and also type 23 short-tandem repeats (Y-STRs) to assess internal diversity. We find three specifically Western-European sub-haplogroups, two of which predominate in Norway and Sweden, and are also found in Britain; star-like features in the STR networks of these lineages indicate histories of expansion. We ask whether geographical distributions of hg R1a1 overall, and of the two sub-lineages in particular, correlate with regions of Scandinavian influence within Britain. Neither shows any frequency difference between regions that have higher (≥10%) or lower autosomal contributions from Norway and Sweden, but both are significantly overrepresented in the region corresponding to the Danelaw. These differences between autosomal and Y-chromosomal histories suggest either male-specific contribution, or the influence of patrilocality. Comparison of modern DNA with recently available ancient DNA data supports the interpretation that two sub-lineages of hg R1a1 spread with the Vikings from peninsular Scandinavia.