Excimer Laser Research Articles

Efficacy of fire needle combined with 308 nm excimer laser therapy for vitiligo: A systematic review and meta-analysis of randomized controlled trials.

Vitiligo is a common depigmenting skin disorder. This work is performed to systematically evaluate the efficacy and safety of fire needles combined with 308 nm excimer laser therapy in treating vitiligo. We searched the PubMed, EMBASE, Cochrane Library, Web of Science, CNKI, Wanfang, and VIP databases. Randomized controlled trials (RCTs) on fire needles combined with 308 nm excimer laser therapy with 308 nm excimer laser therapy alone for vitiligo were included. The Cochrane Collaborative Network Tool was used to assess the risk of bias. Statistical analysis was completed using RevMan5.3 software and Stata 15.0 software. The GRADE system was used to evaluate the quality of evidence for outcomes. In this study, 10 RCTs and 1333 patients were included. The results showed that compared with 308 nm excimer laser therapy alone, fire needle combined with 308 nm excimer laser therapy is more effective in improving clinical effective rate (RR = 1.36, 95% CI [1.24, 1.50], p < 0.00001), serum CD4+ level (MD = 3.12, 95% CI [2.50, 3.74], p < 0.00001), CD4+/CD8+ ratio (MD = 0.24, 95% CI [0.09, 0.39], p = 0.001), and quality of life measured by the Dermatology Life Quality Index (DLQI) (MD = 3.76, 95% CI [3.33, 4.19], p < 0.00001), and reducing the Vitiligo Area Score Index (VASI) (MD = -5.47, 95% CI [-6.56, -4.37], p < 0.00001). The reported adverse events, including redness, swelling, pain, blisters, and itching, were controllable, and all these events were well tolerated. The current evidence indicates that fire needle combined with 308 nm excimer laser therapy is effective and safe for vitiligo. However, owing to the suboptimal quality of the included studies, more high-quality and large-scale RCTs are needed for comprehensive analysis and further validation.

Generation and Quenching in the XeCl* Excimer Laser Pumped by Mixed Gamma-Neutron Radiation from a Nuclear Reactor

Generation and Quenching in the XeCl* Excimer Laser Pumped by Mixed Gamma-Neutron Radiation from a Nuclear Reactor

Outcomes of Excimer Laser Ablation Combined with Drug-coated Balloon in Atherosclerotic Lesions of the Popliteal Artery

BackgroundThe treatment of atherosclerotic lesions in the popliteal artery is challenging. This study aims to investigate the efficacy and safety of excimer laser ablation (ELA) combined with drug-coated balloon (DCB) for these lesions. MethodsFrom June 2019 to December 2021, data of patients who underwent ELA combined with DCB in the popliteal artery were retrospectively reviewed. Demographics, lesion characteristics, periprocedural complications and follow-up information were analyzed. The primary endpoint was primary patency. Secondary endpoints included major amputation-free survival (MAFS) rate, technical success, bailout stenting, clinically-driven target lesion reintervention (CD-TLR), improvement of ankle-brachial index (ABI) and Rutherford class. ResultsA total of 61 patients were enrolled. The mean age was 73.4 ± 11.7 years. 20 (32.8%) patients had stenotic lesions while 41 (67.2%) patients had chronic total occlusions (CTOs). The mean length of these lesion was 7.3 ± 2.8 cm. Procedure technical success rate was 95.1%. Bailout stent was performed in 3 (4.9%) patients. Intraprocedural distal embolization occurred in 3 (4.9%) patients, while flow limiting dissections occurred in 3 (4.9%) patients. The mean ABI was significantly improved from 0.45 ± 0.13 at baseline to 0.90 ± 0.12 after ELA, 0.88 ± 0.11 at 6 months and 0.85 ± 0.12 at 12 months. during the follow-up period. The median follow-up time was 28.2 ± 6.1 months. Reintervention was performed in 5 (8.2%) patients. The 2-year primary patency was 83.5%. ConclusionELA combined with DCB is a safe and effective strategy in the treatment of popliteal artery atherosclerotic lesions with low rates of bail-out stenting and high primary patency.

Fabrication of fluidic submicron-channels by pulsed laser-induced buckling of SiOx films on fused silica

Recently, considerable attention has been drawn to the field of micro/nanofluidic channels. However, current methods for fabricating micro/nanochannels are complex, costly, and time-intensive. In the present work, we successfully fabricated transparent submicron-channels on fused silica substrates (SiO2) using a straightforward laser process. To achieve this, a single-pulse excimer laser irradiation in a rear side configuration was employed to treat a thin film of UV-absorbing silicon suboxide (SiOx) through the transparent SiO2 substrate. A polydimethylsiloxane (PDMS) superstrate (coating layer) was applied over the SiOx film before laser exposure, serving as a confinement for controlled structure formation induced by the laser. Under optimal laser fluence, the thin SiOx film buckled, leading to the formation of channels with a width ranging from 10 to 20 µm and a height of 800 to 1200 nm, exhibiting a bell-like cross-sections following the so-called Euler buckling mode. Wider channels displayed morphologies resembling varicose or telephone cord modes. Subsequent high-temperature annealing led to the oxidation of SiOx, resulting transparent SiO2 channels on the fused silica substrate. The manufactured nanochannels exhibited promising potential for effectively transporting fluids of diverse viscosities. Various fluids were conveyed through these nanochannels via capillary action and in accordance with the Lucas-Washburn equation.

308nm excimer laser and tacrolimus ointment in the treatment of facial vitiligo: a systematic review and meta-analysis.

This study aimed to investigate the effects and safety of 308nm excimer laser (308nm EL) and tacrolimus ointment (TO) in the treatment of facial vitiligo (FV). We searched Cochrane Library, PUBMED, EMBASE, CNKI, and WANGFANG from inception to June 1, 2023. Outcomes included overall response rate (ORR), total adverse reaction rate (TARR), recurrence rate at 3-month (RR-3) and recurrence rate at 6-month (RR-6). The outcome data were presented as odds ratios (OR) with 95% confidence intervals (CI). The risk of bias was assessed by Cochrane risk-of-bias tool and data analysis was performed by RevMan 5.4 software. This study included a total of 19 trials involving 2085 patients. When comparing 308nm EL monotherapy with 308nm EL plus TO, significant differences in the ORR (OR = 4.29, 95% CI [2.97, 6.19], I2 = 0%, P < 0.001), RR-3 (OR = 0.18, 95% CI [0.05, 0.69], I2 = 0%, P = 0.01), and RR-6 (OR = 0.38, 95% CI [0.14, 1.03], I2 = 39%, P = 0.06) were found between the two managements. When comparing TO monotherapy with TO plus 308nm EL, its results showed significant differences in the ORR (OR = 4.21, 95% CI [2.90, 6.11], I2 = 0%, P < 0.001), TARR (OR = 0.42, 95% CI [0.22, 0.81], I2 = 4%, P = 0.009), and RR-3 (OR = 0.32, 95% CI [0.01, 8.03], P = 0.49) between the two modalities. The results of this study suggest that the combination of 308nm EL and TO is more effective than either treatment alone for the treatment of FV.

Topography-guided excimer laser ablation in refractive surgery.

Topography-guided excimer laser ablation in refractive surgery.

Cornea and Anterior Segment Parameters and Their Importance in Eye Disease

Corneal and anterior segment parameters (ASP) are valuable in diagnosis and risk assessment of diseases such as glaucoma and keratoconus and it is also an invaluable tool in patient selection and surgical planning of excimer laser refractive surgery. Devices where cornea and anterior segment parameters are measured include Sirius system, Pentacam, Orbscan, Galilei, Anterior Segment Optical Coherence Tomography (ASOCT).

The Role of a Kind of DID Defect-Open Tear Defect in the Recording of Gratings Using Excimer Lasers in Low-Loss Optical Fibers

The Role of a Kind of DID Defect-Open Tear Defect in the Recording of Gratings Using Excimer Lasers in Low-Loss Optical Fibers

Laser and Lights in Psoriasis.

Psoriasis is a chronic inflammatory skin condition affecting millions of individuals worldwide. Over the years, various treatment modalities have been explored to alleviate the symptoms and improve the quality of life for patients with psoriasis. Among these treatment options, lasers and lights have emerged as promising non-invasive approaches with significant efficacy. This review aims to provide an overview of the current understanding and clinical applications of lasers and lights in the management of psoriasis. We have discussed the mechanisms of action behind different laser and light therapies and their impact on psoriatic plaques. Additionally, we discuss the various types of lasers and lights utilized, including excimer lasers, pulsed dye lasers, and narrowband ultraviolet B (NB-UVB) phototherapy, highlighting their unique properties and clinical outcomes. Moreover, we have addressed important considerations related to patient selection, treatment protocols, and potential side effects associated with lasers and lights. We emphasize the need for proper evaluation, monitoring, and customization of treatment plans to ensure optimal outcomes and minimize adverse events.

Comparative efficacy of interventional therapies and devices for coronary in-stent restenosis: A systematic review and network meta-analysis of randomized controlled trials

BackgroundIn-stent restenosis (ISR) has become a significant obstacle to interventional therapy for atherosclerotic cardiovascular disease. The optimal percutaneous coronary intervention (PCI) strategy for patients with coronary ISR remains controversial. This network meta-analysis (NMA) was aimed to compare and estimate the effectiveness of different PCI strategies and commercial devices for the treatment of patients with coronary ISR. MethodsIn present study, we systematically searched PubMed, Embase, Web of Science, and Cochrane Library from database inception to October 20, 2022, to identify randomized controlled trials. We included studies comparing various PCI strategies for the treatment of any type of coronary ISR. The study was registered with PROSPERO, CRD 42022364308. ResultsWe included 44 eligible trials including 8479 patients, 39 trials comparing the treatment effects of 10 PCIs, and 5 trials comparing the efficacy between different types of drug-eluting stent (DES) or drug-coated balloon (DCB) devices. Among the PCIs, everolimus-eluting stent was the optimal strategy considering target lesion revascularization (TLR), percent diameter stenosis (%DS), and binary restenosis (BR), and sirolimus-coated balloon was the optimal strategy considering late lumen loss (LLL). In the comparison of commercial devices, the combination strategy excimer laser coronary angioplasty plus SeQuent Please paclitaxel-coated balloon showed promising therapeutic prospects. ConclusionsDCB and DES remain the preferred treatment strategies for coronary ISR, considering both the primary clinical outcome (TLR) and the angiographic outcomes (LLL, BR, %DS). Personalized combination interventions including DCB or DES hold promise as a novel potential treatment pattern for coronary ISR.

Refractive results of photorefractive keratectomy comparing trans-PRK and PTK−PRK for correction of myopia and myopic astigmatism

PurposeTo compare refractive outcomes after transepithelial photorefractive keratectomy (tPRK) and combined phototherapeutic keratectomy (PTK−PRK) procedure using two different excimer laser platforms for correction of myopia and myopic astigmatism.MethodsIn this retrospective multicenter study, we compared the results of two different PRK methods. The first group received a tPRK treatment with the Amaris750 excimer laser (Schwind eye-tech solutions). The second group received a combined PTK−PRK treatment with the MEL90 excimer laser (Carl Zeiss). Only healthy eyes with no previous surgery and a spherical equivalent (SE) of −1 to −8 diopters (D) were included. Preoperative spherical equivalent (SE), age, and sex were matched among the two groups. All treatments were performed by the same surgeon in different clinics. This study was approved by the local Ethics Committee (No. 2022–1980).ResultsWe included 154 eyes of 86 patients in our study. There was no difference in predictability of SE between the two groups. Efficacy and safety indices were equally high in both groups. Similarly, no significant differences were seen in change of higher order aberrations (HOA) between the two groups (p > 0.05). No complications occurred.ConclusionBoth investigated methods provide safe and effective refractive results. The combination of PTK with PRK may be a suitable option to the already used one-step tPRK for the correction of myopia.

Advancing (U-Th)/He Zircon Dating: Novel Approaches in Sample Preparation and Uncertainty Reduction

Abstract The laser microprobe (U-Th)/He dating method is a new and efficient technique that utilizes an interoperable and integrated suite of instruments, including the excimer laser system, quadrupole helium mass spectrometer, and quadrupole inductively coupled plasma mass spectrometer. To demonstrate the applicability of this new method, we applied both the conventional and laser microprobe techniques to the Sri Lanka zircon (LGC-1). We obtained twenty-two (U-Th)/He ages on nine shards using the laser microprobe method, showing an average (U-Th)/He age of 471.1 ± 16.6 Ma (1σ). This result is generally consistent with the mean conventional age (484.1 ± 9.6 Ma) for twenty-two zircon fragments. Both are nearly equal to the age value (~476 Ma) predicted by the He diffusion model and the thermal history model of Sri Lanka highland. The variations in the laser microprobe-derived ages are most likely caused by the uncertainties in volume measurements, which is also common in other studies. We used the Mahalanobis distance technique to reduce the volume measurement bias by identifying and eliminating abnormal data.

Nanoscale Dots, Grids, Ripples, and Hierarchical Structures on PET by UV Laser Processing

Nanostructures can be produced on poly(ethylene terephthalate) (PET) foils by using a krypton fluoride (KrF) excimer laser with a wavelength of 248 nm and a pulse duration of about 20 ns. We show that surface nanoripples, nanodots, nanogrids, and hybrid patterns of ripples with dots or finer ripples on top can be fabricated. The effects of a water layer in front of the PET foil and of cooling during laser processing were investigated. For pattern formation, several irradiation parameters (pulse number, pulse energy, and polarization) were varied systematically. The spatial periods of the ripples were changed by adjusting the angle of incidence of the laser beam. All nanostructures were characterized by scanning electron microscopy, and relevant morphological parameters, such as peak-to-peak distances and spatial periods, were assessed. Shapes and heights of some structures were characterized by using focused ion beam cuts to avoid the tip-sample convolution effects typical of atomic force microscopy images. We further demonstrate nanoripple formation on PET foils as thin as 12 µm, 6 µm, and 1.4 µm. The remarkable variety of nanostructures on PET we present here enables customized fabrication for a wide range of applications.

Comparison of early changes in tear film protein profiles after small incision lenticule extraction (SMILE) and femtosecond LASIK (FS-LASIK) surgery

BackgroundSmall incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (LASIK) are widely used surgical methods to correct myopia with comparable efficacy, predictability, and safety. We examined and compared the early changes of tear protein profiles after SMILE and FS-LASIK surgery in order to find possible differences in the initial corneal healing process.MethodsSMILE operations for 26 eyes were made with Visumax femtosecond laser. In FS-LASIK surgery for 30 eyes, the flaps were made with Ziemer FEMTO LDV Z6 femtosecond laser and stromal ablation with Wavelight EX500 excimer laser. Tear samples were collected preoperatively, and 1.5 h and 1 month postoperatively using glass microcapillary tubes. Tear protein identification and quantification were performed with sequential window acquisition of all theoretical fragment ion spectra mass spectrometry (SWATH-MS).ResultsImmediately (1.5 h) after we found differences in 89 proteins after SMILE and in 123 after FS-LASIK operation compared to preoperative protein levels. Of these differentially expressed proteins, 48 proteins were common for both surgery types. There were, however, quantitative differences between SMILE and FS-LASIK. Upregulated proteins were mostly connected to inflammatory response and migration of the cells connected to immune system. One month after the operation protein expressions levels were returned to baseline levels with both surgical methods.ConclusionsOur study showed that immediate changes in protein profiles after SMILE and FS-LASIK surgeries and differences between the methods are connected to inflammatory process, and the protein levels quickly return to the baseline within 1 month. The differences in protein profiles between the methods are probably associated with the different size of the epithelial wound induced.

Use of In Vivo Corneal Confocal Microscopy to Guide Excimer Laser With Adjunctive Mitomycin C for Treatment of Recalcitrant Acanthamoeba Keratitis.

The aim of this study was to describe 3 cases of recalcitrant Acanthamoeba keratitis (AK) that were successfully treated using in vivo corneal confocal microscopy (IVCM) to guide excimer laser ablation depth with adjunctive mitomycin C 0.02%. Three patients diagnosed with AK did not respond to several weeks of intensive topical therapy with antiamoebic agents. The patient underwent phototherapeutic keratectomy with topical mitomycin C 0.02% application. The maximum stromal depth of cysts measured by IVCM was 80 μm, 100 μm, and 240 μm, and the stromal ablation depths were 80 μm, 100 μm, and 100 μm, respectively. In all 3 eyes, AK resolved after a single excimer laser application, and topical treatment was gradually discontinued within 6 weeks afterward. In 1 eye, penetrating corneal transplantation was performed 6 weeks after phototherapeutic keratectomy because of ongoing severe corneal pain. IVCM and histology of the corneal transplant did not reveal any Acanthamoeba cysts within the excised corneal button. No recurrence was observed during the follow-up period of 19 to 34 months. IVCM-guided phototherapeutic keratectomy with mitomycin C 0.02% seems to be a safe and successful approach for the treatment of AK, especially in cases of resistance to topical treatment. Corneal IVCM should be performed before laser application to measure cyst depth, determine ablation depth, and assess postoperative treatment success.

Excimer laser coronary atherectomy in severely calcified lesions: time to bust the myth

Excimer laser coronary atherectomy in severely calcified lesions: time to bust the myth

Safety and efficacy of implantable phakic contact lens versus implantable collamer lens in myopia correction.

Phakic intraocular lenses (pIOLs) have proven to be excellent substitutes for excimer laser keratorefractive surgery in certain situations. We aimed to assess the efficacy and safety of two pIOLs, the implantable collamer lens (ICL V4c) versus the implantable phakic contact lens (IPCL V2), for myopic correction. In this prospective randomized clinical trial, we allocated eligible eyes with myopia > - 6 diopters into IPCL or ICL implantation groups, each including 100 eyes of 100 individuals. Preoperative and postoperative assessments at 3, 6, and 12 months included measurements of the spherical equivalent (SE), uncorrected distance visual acuity (UCDVA), best-corrected distance visual acuity (BCDVA), intraocular pressure (IOP), maximum keratometry (K1), minimum keratometry (K2), mean keratometry (Kmean), anterior chamber depth (ACD), anterior chamber angle (ACA), and endothelial cell density (ECD). The groups had comparable demographic characteristics and baseline visual and anatomical values (all P > 0.05). The UCDVA, BCDVA, and SE of the two groups were comparable at baseline and at all postoperative follow-up examinations (all P > 0.05). Both groups experienced significant improvements in UCDVA, BCDVA, and SE at three months postoperatively (all P = 0.001), and measurements remained stable for up to 12 months. Keratometry readings were comparable between the groups over the follow-up period and remained unchanged at all visits (all P > 0.05). The ACA in the ICL group was significantly decreased at three months postoperatively (P = 0.001) and then widened significantly at 6 and 12 months (both P = 0.001). In the IPCL group, the postoperative ACA was significantly decreased at three months (P = 0.001) and was comparable to that in the ICL group (P > 0.01). However, at the 6- and 12-month postoperative visits, the ACA was significantly narrower in the IPCL group than in the ICL group (both P = 0.001). The ACD in both groups was decreased at three months postoperatively (both P = 0.001) and remained stable until the end of the study. The ECD remained comparable between the groups at all postoperative visits (all P > 0.05). We did not observe a significant ECD reduction in either group at any postoperative follow-up visit (all P > 0.05). We encountered no serious complications in either group. ICL and IPCL had comparable safety and efficacy outcomes in terms of anterior chamber morphometrics, visual and refractive results, and corneal parameters. Further multicenter randomized clinical trials with longer follow-up periods, larger sample sizes, and measurement of additional anterior chamber and corneal morphometrics, vault, and other vision parameters are needed to verify these findings.

Performance Improvement of In-Ga-Zn Oxide Thin-Film Transistors by Excimer Laser Annealing.

We applied excimer laser annealing (ELA) on indium-zinc oxide (IZO) and IZO/indium-gallium-zinc oxide (IGZO) heterojunction thin-film transistors (TFTs) to improve their electrical characteristics. The IZO and IZO/IGZO heterojunction thin films were prepared by the physical vapor deposition method without any other annealing process. The crystalline state and composition of the as-deposited film and the excimer-laser-annealed films were analyzed by X-ray diffraction and X-ray photoelectron spectroscopy. In order to further enhance the electrical performance of TFT, we constructed a dual-heterojunction TFT structure. The results showed that the field-effect mobility could be improved to 9.8 cm2/V·s. Surprisingly, the device also possessed good optical stability. The electron accumulation at the a-IZO/HfO, HfO/a-IGZO, and a-IGZO/gate insulator (GI) interfaces confirmed the a-IGZO-channel conduction. The dual-heterojunction TFT with IZO/HfO/a-IGZO-assisted ELA provides a guideline for overcoming the trade-off between high mobility (μ) and positive VTh control for stable enhancement mode operation with increased ID.

Progress and Outlook of 10% Efficient AlGaN‐Based (290–310 nm) Band UVB LEDs

Eco‐friendly and low‐cost aluminum gallium nitride (AlGaN) for the epitaxial growth of ultraviolet‐B (UVB) light‐emitting diodes (LEDs) on c‐Sapphire has the possibility of high external‐quantum efficiency (EQE). In this review paper a special growth techniques for 50% relaxed and 4 μm thick AlGaN buffer layer underneath the multi‐quantum wells (MQWs) are challenged to achieve a maximum internal‐quantum efficiency of 50–57% in 310–290 nm band UVB LEDs. The influence of a thin “Valley” layer in p‐type multi‐quantum barrier electron‐blocking layer on 2D hole generation and injection via intraband tunneling was attempted. Finally, the influence of soft polarized Mg‐doped p‐type Al‐graded AlGaN hole injection layer assisted by excimer laser annealing for better hole injection toward the MQWs was investigated and quite high hole concentration of 2 × 1016 cm−3 and resistivity of 24 Ω‐cm at room temperature was achieved. Consequently, the EQE of transparent 310 and 304 nm UVB LEDs, respectively, reached to a confirmed world record values of ≈5% and ≈10% with light powers of 29 and 40 mW on wafer. This EQE value can surpass 21% if flip‐chip, nanoPSS, photonic crystal, and lens with highly reflective p‐electrodes are incorporated in LED.

Principal Analysis and Application of Laser Technology in Integrated Circuits

Since the constant development of science and technology and the popularization of electronic devices, integrated circuits are also developing in the direction of large scale and high precision. This requires the processing of integrated circuits to be constantly refined. This also prompted the laser technology has become an important processing technology in the manufacturing process of large-scale integrated circuits. Laser processing technology is a non-contact processing, its beam diameter is small, high-energy density, high productivity, stable and reliable processing quality. This paper for the laser welding, laser direct writing, laser detection and laser cleaning overview of the four-laser technology in the application of large-scale integrated circuits. And the working principle, type and process characteristics of these laser technologies are discussed. The development of laser technology has also limited the production of large-scale integrated circuits in some aspects. With the semiconductor laser, excimer laser process continues to mature, laser technology in integrated circuits will continue to expand the scope of application and break through the obstacles.