Nowadays, lasers are used in various medical fields. Ophthalmology was the first medical specialty to utilize lasers in patient treatment and still remains the leading medical field that uses laser energy for both therapeutic and diagnostic purposes. The neodymium: yttrium-aluminum-garnet (Nd: YAG) laser is one of the most common lasers used in ophthalmology. It is a solid-state laser with a wavelength of 1064 nm that works on the principle of photodisruption. Since its introduction in ophthalmology over 40 years ago, it has found various applications, mainly for procedures where cutting or disruption of ocular tissue is required. Compared to surgical alternatives, the use of Nd: YAG lasers on ocular tissue is minimally invasive. In this review, we focus on the two most common ophthalmic applications of Nd: YAG laser - laser peripheral iridotomy and posterior capsulotomy. The history of the techniques, current trends, potential complications, and the prognosis for future use is discussed.

OBJECTIVE: The study aims to determine the effects of Nd:YAG laser-assisted with subgingival scaling and root planing (SRP) treatment on glucose control and the dynamic changes of subgingival microbiome in periodontitis with type 2 diabetes mellitus (T2DM).
METHODS: Twenty-two patients were split into Nd:YAG group (n = 11) and SRP group (n = 11). Patients in the Nd:YAG group received SRP and auxiliary Nd:YAG laser treatment; patients in the SRP group received SRP treatment only. Periodontal tissue inflammation and glycemic control were assessed and analyzed during the treatment period and the changes of subgingival microbiome were analyzed by full-length 16S rRNA sequencing.
RESULTS: After 3 months of treatment, PD and CAL values improved significantly in the Nd:YAG group compared to the SRP group. BOP in both groups improved significantly after treatment. FPG levels in the Nd:YAG group were significantly reduced after treatment. Porphyromonas and Porphyromonadaceae were enriched in the Nd:YAG group at baseline, and Fusobacteriota, Fusobacteriia, Fusobacteriales, Leptotrichiaceae, and Leptotrichia were enriched after treatment.
CONCLUSIONS: Nd:YAG laser-assisted SRP therapy has additional benefits in improving periodontal tissue inflammation and blood glucose control in periodontitis patients with T2DM compared with SRP therapy alone and there was a trend towards a decrease in disease-associated taxa and an increase in health-associated taxa following auxiliary Nd:YAG laser treatment.
CONCLUSIONS: The effects of Nd:YAG laser-assisted SRP treatment on inflammation, glucose control, and subgingival microbiome in periodontitis patients with T2DM were elucidated, and new ideas for the treatment of T2DM periodontitis were provided.

Objective To assess the effects of different application sequences of neodymium-doped yttrium aluminum garnet(Nd∶YAG)laser and the desensitizing toothpaste containing stannous fluoride on dentinal tubule occlusion.Methods Twelve intact third molars freshly extracted from human were selected and prepared into dentin slices with a thickness of 0.8 mm.Each dentin slice was subdivided into four small slices,three of which were etched with 6% citric acid and randomly assigned to the following three groups(n=12):(1)control group:no treatment;(2)Nd∶YAG+toothbrushing(TB)group:first irradiated with Nd∶YAG laser and then brushed with desensitizing toothpaste;(3)TB+Nd∶YAG group:first brushed with desensitizing toothpaste and then irradiated with Nd∶YAG laser.The Nd∶YAG laser irradiation were carried out at 1 W,15 pulses/s,and the pulse width of 150 μs for 10 s(for a total of 6 cycles).After the above treatment,the 12 dentin slices from the Nd∶YAG+TB and TB+Nd∶YAG groups were randomly assigned to four subgroups(n=3)and subjected to acid etching in the Coca-Cola solution for 0,5,10,and 15 min.A scanning electron microscope was used to observe and photograph the dentin slices in each group,and eight single-blinded examiners scored the slices according to uniform criteria.The analysis of variance was carried out to compared the scores between groups.Results Before acid etching,the dentin tubule occlusion scores of the Nd∶YAG+TB and TB+Nd∶YAG groups were(4.83±0.09) scores and(3.85±0.66) scores,respectively,which had no significant difference between each other(P=0.0590)and were higher than that[(0.10±0.07)scores]of the control group(both P<0.0001).The dentin tubule occlusion scores of the Nd∶YAG+TB group after acid etching for 5,10,and 15 min were(4.33±0.60)scores,(4.27±0.24)scores,and(3.63±0.07)scores,respectively,which were not significantly different from those[(4.04±0.10)scores,(3.76±0.59)scores,and(3.17±0.29)scores,respectively]of the TB+Nd∶YAG group(all P>0.05).In the Nd∶YAG+TB subgroup,the dentin tubule occlusion score after acid etching for 15 min was significantly lower than that before acid etching(P=0.0011).In the TB+Nd∶YAG group,there was no statistically significant difference in the score between before and after acid etching(P>0.05).Conclusions Nd∶YAG laser irradiation with appropriate parameters combined with the use of desensitizing toothpaste could produce an excellent occluding effect on dentinal tubules regardless of the sequence.However,brushing with desensitizing toothpaste followed by Nd∶YAG laser irradiation produced more consistent dentin sealing after acid etching.
目的 评估掺钕钇铝石榴石(Nd∶YAG)激光和含有氟化亚锡系统的脱敏牙膏不同应用顺序对牙本质小管封闭效果的影响。方法 选择12颗完整的新鲜拔除的人第三磨牙制备成0.8 mm厚牙本质片,将每个牙本质片再分为4小片,取其中3小片,用6%的柠檬酸进行腐蚀,随机分配至以下3组(n=12):(1)对照组:无处理;(2)Nd∶YAG激光+牙膏(TB)组:先用Nd∶YAG激光照射,后用脱敏牙膏刷牙;(3)TB+Nd∶YAG组:先用脱敏牙膏刷牙,后用Nd∶YAG激光照射。Nd∶YAG激光照射参数均为:1 W,15脉冲/s,脉冲宽度150 μs,照射10 s,6个循环。经上述处理后,将Nd∶YAG+TB组和TB+Nd∶YAG组的12个牙本质片随机分配到4个亚组(n=3),分别在可口可乐液中接受酸蚀0、5、10、15 min。采用扫描电子显微镜观察各组牙本质片并拍片,由8名单盲检查员根据统一标准给出评分,采用方差分析对各组评分进行比较。结果 酸蚀前,Nd∶YAG+TB组和TB+Nd∶YAG组的牙本质小管封闭评分分别为(4.83±0.09)分和(3.85±0.66)分,均明显高于对照组的(0.10±0.07)分(P均<0.0001),Nd∶YAG+TB组与TB+Nd∶YAG组差异无统计学意义(P=0.0590)。Nd∶YAG+TB组酸蚀5、10、15 min牙本质小管封闭评分分别为(4.33±0.60)、(4.27±0.24)、(3.63±0.07)分,与TB+Nd∶YAG组的(4.04±0.10)、(3.76±0.59)、(3.17±0.29)分差异均无统计学意义(P均>0.05)。在Nd∶YAG+TB亚组中,酸蚀15 min牙本质小管封闭评分明显低于酸蚀前(P=0.0011)。在TB+Nd∶YAG组中,酸蚀前后牙本质小管封闭评分间差异无统计学意义(P>0.05)。结论 适当参数的Nd∶YAG激光照射结合使用脱敏牙膏,不论先后顺序,均可以产生良好的牙本质小管封闭效果,但是先用脱敏牙膏刷牙后用Nd∶YAG 激光照射组在酸蚀后的牙本质封闭效果更稳定。.

UNASSIGNED: The role of lasers in the treatment of standard therapy-resistant inflammatory dermatoses and connective tissue disorders has been controversial and evidence supporting the role of lasers in this setting is scarce.
UNASSIGNED: To assess the efficacy of lasers in the management of inflammatory dermatoses and connective tissue disorders (CTD).
UNASSIGNED: A retrospective case review of all inflammatory dermatoses/connective tissue diseases treated in a tertiary laser clinic between March 2010 and 2020 was undertaken.
UNASSIGNED: A total of 60 cases (48 = female) were included and the average age was 51 years (range 21 to 74). The following conditions were treated: scleroderma n = 22 (37%), granuloma faciale n = 10 (17%), sarcoidosis n = 8 (13%), discoid lupus erythematosus n = 7 (12%), and systemic lupus erythematosus n = 2 (3%). Other diagnoses included necrobiosis lipoidica, pyoderma vegetans, hypertrophic lichen planus, and dermatomyositis. The most common type of laser used was pulsed dye laser (PDL) in n = 41 (68%) cases. Eight (13%) patients received treatment with the carbon dioxide (CO2) laser. The most common site treated was the face. A good response with a marked reduction of signs was seen in 62% of patients while 10% of the patients did not respond to laser treatment. Self-limiting complications included purpura and hyperpigmentation.
UNASSIGNED: Lack of objective assessment and outcome measures.
UNASSIGNED: This is the largest cohort of patients to have undergone laser treatment for inflammatory dermatoses/connective tissue disease. Based on this retrospective review, we conclude that lasers can be a useful adjunct in the management of otherwise difficult-to-treat selected inflammatory and connective tissue diseases.

The aim of this study is to histologically characterize the wound healing process of in vivo human skin treated with 1064- and 532-nm microlens array (MLA)-type picosecond lasers.
Three patients (Fitzpatrick skin types II-IV), who were undergoing future cosmetic abdominoplasties, were treated with 1064- and 532-nm MLA-type lasers under different fluence settings. Treatments were performed 2 weeks, 1 week, and immediately prior to surgery. Skin samples were harvested from the resected tissue with 8 mm punch biopsies immediately after the abdominoplasties were performed.
The study demonstrates that intraepidermal vacuoles, created from tissue damage induced by the laser, are histologically resolved within 1 week without persistent damage to the dermoepidermal junction or vasculature. After 2 weeks, all foci of microscopic epidermal necrotic debris had either resolved or migrated to more superficial levels in the stratum corneum. There was no evidence of persistent vascular damage, increased melanophages, or accumulation of melanin in the dermis at 2 weeks. Furthermore, the 1064-nm picosecond laser with the high fluence setting demonstrated the capacity to fractionally ablate the epidermis and induce multifocal fibrosis in the papillary dermis in lighter skin types.
This is the first study to demonstrate the wound healing profile of in vivo human skin after treatment with the picosecond 1064- and 532-nm MLA-type lasers. It shows that laser-induced tissue damage is histologically resolved within 2 weeks, clinically reflecting a favorable safety profile and short downtime. The study also shows that the picosecond laser can be used to induce either fractional ablative or non-ablative effects, depending on the fluence settings used. Lasers Surg. Med. © 2021 Wiley Periodicals LLC.

BACKGROUND: Picosecond-domain laser treatment using a microlens array (MLA) or a diffractive optical element (DOE) generates micro-injury zones in the epidermis and upper dermis.
OBJECTIVE: To investigate interactive tissue reactions between MLA-type picosecond laser pulses and cohesive polydensified matrix hyaluronic acid (CPMHA) filler in the dermis.
METHODS: In vivo rats with or without CPMHA pretreatment were treated with a 1064-nm picosecond-domain neodymium:yttrium-aluminum-garnet (Nd:YAG) laser using an MLA or DOE. Skin samples were obtained at post-treatment days 1, 10, and 21 and histologically and immunohistochemically analyzed.
RESULTS: Picosecond-domain Nd:YAG laser treatment with an MLA-type or a DOE-type handpiece generated fractionated zones of pseudo-cystic cavitation along the lower epidermis and/or upper papillary dermis at Day 1. At Day 21, epidermal thickness, dermal fibroblasts, and collagen fibers had increased. Compared to CPMHA-untreated rats, rats pretreated with CPMHA showed marked increases in fibroblasts and collagen fibers in the papillary dermis. Immunohistochemical staining for the hyaluronic acid receptor CD44 revealed that MLA-type picosecond laser treatment upregulated CD44 expression in the basilar epidermis and dermal fibroblasts.
CONCLUSIONS: We suggest that the hyaluronic acid-rich environment associated with CPMHA treatment may enhance MLA-type picosecond-domain laser-induced tissue reactions in the epidermis and upper dermis.

Nanosecond Q-switched lasers have been used for the removal of traditional and cosmetic tattoos. Picosecond lasers utilize pulse durations of 10-12 and provide more efficient clearance of tattoos. Safe and effective removal of tattoos is especially important in cosmetically sensitive areas such as the face. We report four patients with skin types (III-IV) who have had successful removal of eyebrow tattoos with the picosecond (1,064-, 532-nm) laser using a perfluorodecalin-infused patch (PFD).
Patients with eyebrow tattoos underwent treatment with dual-wavelength picosecond Nd:YAG laser at 1,064-nm with a 3 mm spot size and fluence of 4-4.6 J/cm2 . The 532-nm wavelength was also used during treatment #1 (patient 2 only) with a 4 mm spot size and fluence of 0.5 J/cm2 . Patient 1 had a total of three treatments (6-8 weeks apart). The remaining patients, each had only one treatment. Patients were photographed prior to treatment and subsequently at each follow-up.
Immediately following each laser treatment, only mild and transient localized erythema and edema was observed. Some epidermal crusting was noted for 3-5 days following each treatment. Eyebrow hair growth was not affected and no adverse events were reported. There was 75% clearance in patient 1 after three treatments over a period of 2.5 months, 75% clearance in patient 2 after one treatment, 90% clearance in patient 3 after one treatment, and 100% clearance in patient 4 after one treatment.
The 532- and 1,064-nm wavelength of the picosecond Nd:YAG laser was safely used to clear brown and black ink eyebrow tattoos in four patients, three of whom were skin type IV, and one of whom underwent eyebrow tattoo via microblading, a novel and popular technique for cosmetic tattoos. The use of picosecond laser provides several treatment advantages to Q-switched laser when treating eyebrow tattoos. In our experience, it required less number of treatments and lower fluences. This, along with use of the perfluorodecalin-infused patch resulted in excellent outcomes for our patients with no significant side effects. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

UNASSIGNED: The aim of this study was to compare and evaluate the efficacy of neodymium-doped yttrium aluminum garnet laser with and without herbal and nanohydroxyapatite dentifrices in management of dentinal hypersensitivity (DH).
UNASSIGNED: A total of 180 patients who responded to air-blast test and cold-water test using verbal rating scale (VRS) were included in this study. The patients were randomly assigned to six groups (n = 30): control group (CG), scaling and root planning (SRP) + nanocrystalline hydroxyapatite dentifrices, SRP + nanocrystalline hydroxyapatite dentifrices + laser, SRP + herbal dentifrices, SRP + herbal dentifrices + laser, and SRP + laser. Each group was evaluated at baseline, 1 week, 1 month, and 6 months. In every visit of each patient, their clinical examination was done.
UNASSIGNED: Among all groups\', repeated ANOVA measures and Kruskal-Wallis test was performed in which laser groups showed maximum reduction in DH in all indices while the CG showed minimum reduction in DH. The VRS values showed maximum reduction in SRP + nanocrystalline hydroxyapatite dentifrices + laser group with mean of 0.3 ± 0.5 and minimum reduction in CG with mean of 3.0 ± 0.5 (P < 0.001).
UNASSIGNED: Among all the groups, SRP + Nanocrystalline hydroxyapatite + Laser can be an effective treatment modality for DH.

OBJECTIVE: To investigate the rate of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy in the hydroimplantation intraocular lens (IOL) technique.
METHODS: This retrospective study was comprised of 6,192 eyes in 3,790 patients who underwent surgery from January 2013 to September 2017 and then were followed up for at least 1 year. The eyes of these patients were divided into two groups: either viscoimplantation or hydroimplantation. The follow-up examinations were carried out on the 1st day, 4th day, 1st month, and 3 months to 1 year postoperatively. The Nd:YAG capsulotomy rates were evaluated by the different IOL implantation techniques and IOL materials.
RESULTS: The mean follow-up duration of the patients was in the viscoimplantation group 14.85 ± 2.43 and 15.05 ± 1.93 months in the hydroimplantation group. The Nd:YAG capsulotomy rate was significantly lower in the hydroimplantation group compared with the viscoimplantation group for the entire hydrophilic IOL model (p < 0.001). In addition, the Nd:YAG rate was lower in the hydroimplantation group that used a hydrophilic IOL than it was in the viscoimplantation group, which used a hydrophobic IOL.
CONCLUSIONS: The hydroimplantation technique reduced the Nd:YAG capsulotomy rate.

BACKGROUND: Laser ablation (LA) with a neodymium-doped yttrium aluminum garnet (Nd:YAG) laser is a minimally invasive approach able to achieve a high rate of complete tissue necrosis. In a previous study we described the feasibility of EUS-guided Nd:YAG pancreas LA performed in vivo in a porcine model.
OBJECTIVE: To establish the best laser setting of Nd:YAG lasers for pancreatic tissue ablation. A secondary aim was to investigate the prediction capability of a mathematical model on ablation volume.
METHODS: Ex vivo animal study.
METHODS: Hospital animal laboratory.
METHODS: Explanted pancreatic glands from 60 healthy farm pigs.
METHODS: Laser output powers (OP) of 1.5, 3, 6, 10, 15, and 20 W were supplied. Ten trials for each OP were performed under US guidance on ex vivo healthy porcine pancreatic tissue.
METHODS: Ablation volume (Va) and central carbonization volume (Vc) were measured on histologic specimens as the sum of the lesion areas multiplied by the thickness of each slide. The theoretical model of the laser-tissue interaction was based on the Pennes equation.
RESULTS: A circumscribed ablation zone was observed in all histologic specimens. Va values grow with the increase of the OP up to 10 W and reach a plateau between 10 and 20 W. The trend of Vc values rises constantly until 20 W. The theoretical model shows a good agreement with experimental Va and Vc for OP between 1.5 and 10 W.
CONCLUSIONS: Ex vivo study.
CONCLUSIONS: Volumes recorded suggest that the best laser OP could be the lowest one to obtain similar Va with smaller Vc in order to avoid the risk of thermal injury to the surrounding tissue. The good agreement between the two models demonstrates the prediction capability of the theoretical model on laser-induced ablation volume in an ex vivo animal model and supports its potential use for estimating the ablation size at different laser OPs.