Search Results (504)

The cornea is an avascular, immune-privileged tissue critical to maintaining transparency, optimal light refraction, and protection from microbial and immunogenic insults. Corneal neovascularization (CoNV) is a pathological sequela of multiple anterior segment diseases and presents a major cause for reduced visual acuity and overall quality of life. Various aetiologies, including infection (e.g., herpes simplex), inflammation (e.g., infective keratitis), hypoxia (e.g., contact lens overuse), degeneration (e.g., chemical burns), and trauma, disrupt the homeostatic avascular microenvironment, triggering an overactive compensatory response. This response is governed by a complex interplay of pro- and anti-angiogenic factors. This review investigates the potential for these mediators to serve as therapeutic targets. Current therapeutic strategies for CoNV encompass topical corticosteroids, anti-VEGF injections, fine-needle diathermy, and laser modalities including argon, photodynamic therapy and Nd:YAG. Emerging therapies involve steroid-sparing immunosuppressants (including cyclosporine and rapamycin), anti-fibrotic agents and advanced drug delivery systems, including ocular nanosystems and viral vectors, to enhance drug bioavailability. Adjunctive therapy to attenuate the protective corneal epithelium prior to target neovascular plexi are further explored. Gene-based approaches, such as Aganirsen (antisense oligonucleotides) and CRISPR/Cas9-mediated VEGF-A editing, have shown promise in preclinical studies for CoNV regression and remission. Given the multifactorial pathophysiology of CoNV, combination therapies targeting multiple molecular pathways may offer improved visual outcomes. Case studies of CoNV highlight the need for multifaceted approaches tailored to patient demographics and underlying ocular diseases. Future research and clinical trials are essential to elucidate optimal therapeutic strategies and explore combination therapies to ensure better management, improved treatment outcomes, and long-term remission of this visually disabling condition. Full article

Background and Clinical Significance: Tramadol-associated acute angle-closure crisis is rare and has been reported only once previously following subcutaneous administration. Acute angle closure may occur in anatomically predisposed individuals in the setting of perioperative physiological stress, with medications acting as contributory factors. Case Presentation: A 38-year-old woman developed a bilateral acute angle-closure crisis shortly after initiating oral tramadol for postoperative pain relief following an uncomplicated robotic-assisted laparoscopic hysterectomy. Within 24 h, she experienced headache, nausea, vomiting, periocular pain, and blurred vision. Ophthalmic examination revealed markedly elevated intraocular pressure (45 mmHg OD, 39 mmHg OS), corneal epithelial edema, mid-dilated pupils, and completely closed angles on gonioscopy. Prompt intraocular pressure–lowering therapy followed by bilateral Nd:YAG laser peripheral iridotomy resulted in full anatomical and functional recovery, with visual acuity returning to baseline within 48 h. Conclusions: In this case, extreme anatomical susceptibility due to significant hyperopia and very short axial lengths likely played a dominant role, with perioperative physiological factors contributing to pupillary dilation. Oral tramadol may have acted as a permissive factor lowering the threshold for angle closure rather than as a sole causative agent. Awareness of this potential association is important to facilitate early ophthalmic referral and prevent unnecessary diagnostic evaluations. Full article

This work presents results on laser-induced fabrication of metal and oxide structures on glass substrates. The Laser-Induced Reverse Transfer (LIRT) technique is applied using Zn and Sn, sintered ZnO and SnO₂, and oxide composite targets. The processing is performed by nanosecond pulses of a Nd:YAG laser system operated at wavelength of 1064 nm. Detailed analyses of the deposited material morphology, composition and structure are presented, as the role of the processing conditions is revealed. It is found that at the applied conditions of using up to five laser pulses, the deposited material is composed of a nanostructured film covered in microsized nanoparticle clusters or droplets. The use of metal targets leads to formation of structures composed of metal and oxide phases. The adhesion test shows that part of the deposited material is stably adhered to the substrate surface. It is demonstrated that the deposited materials can be used as resistive gas sensors with sensitivity to NH₃, CO, ethanol, acetone and N₂O, at concentrations of 30 ppm. The ability of the method to deposit composite structures that consist of a mixture of both investigated oxides is also demonstrated. Full article

We demonstrate that pulsed laser annealing induces plasmonic gold nanoparticles in ZnO thin films, monitored in real-time via pulse-by-pulse spectroscopy. Initially embedded gold nanoparticles (smaller than 5 nm) in sputtered ZnO films were annealed using 532 nm pulses from a Q-switched Nd:YAG laser while monitoring transmission spectra in situ. A plasmonic resonance dip emerged after ~100 pulses in the 530–550 nm region, progressively deepening with continued exposure. Remarkably, different incident energies converged to a thermodynamically stable optical state centered near 555 nm, indicating robust nanoparticle configurations. After several hundred laser shots, the process stabilized, producing larger nanoparticles (40–200 nm diameter) with significant surface protrusion. SEM analysis confirmed substantial gold nanoparticle growth. Theoretical modeling supports these observations, correlating spectral evolution with particle size and embedding depth. The protruding gold nanoparticles can be functionalized to detect specific biomolecules, offering significant advantages for biosensing applications. This approach offers superior spatial selectivity and real-time process monitoring compared to conventional thermal annealing, with potential for optimizing uniform nanoparticle distributions with pronounced plasmonic resonances for biosensing applications. Full article

Urban pollution—especially SO₂ and particulate matter—rapidly darkens and degrades outdoor-exposed wall paintings due to soiling. Laser cleaning has emerged as a cutting-edge solution, offering selective removal of contaminant layers while preserving the integrity of the underlying materials. This study explores the performance of a 355 nm Nd:YAG laser in cleaning artificially aged paint mock-ups coated with real diesel soot and exposed to an accelerated aging test with SO₂ exposure. Traditional mineral pigments—silicates (Egyptian blue, ultramarine blue, and green earth), oxides (chromium green, mars red), and a sulphide (cinnabar)—were applied following fresco and secco (egg yolk) techniques, allowing researchers to uncover how pigment chemistry and binders affect laser sensitivity. Damage thresholds were first determined for each pigment and painting technique via digital photography, stereomicroscopy, and colour spectrophotometry. Cleaning efficacy was then assessed by stereomicroscopy, colour spectrophotometry, Fourier-transform infrared spectroscopy, and scanning electron microscopy. The results revealed clear patterns: silicate pigments exhibit stability under laser irradiation, enabling safe cleaning, whereas mars red and cinnabar remain highly sensitive regardless of the technique. Generally, secco paintings were more susceptible to laser radiation than fresco. These finding provide practical guidance for optimising laser-cleaning protocols while safeguarding the delicate surfaces of historic wall paintings. Full article

Background: Onychomycosis is a common nail infection primarily caused by Trichophyton rubrum, posing therapeutic challenges due to poor antifungal penetration and high recurrence rates. Conventional treatments include topical and systemic antifungals, but novel approaches such as laser therapy and chemical agents like nitric acid have emerged as promising alternatives or adjuncts. However, comparative evidence regarding the clinical and mycological efficacy of these treatments remains limited. Objectives: We aimed to assess and compare the clinical and mycological efficacy of three therapeutic modalities—69% nitric acid, 1064 nm Nd:YAG laser, and their combination—in the treatment of Trichophyton rubrum onychomycosis over a 12-month follow-up period. Methods: A prospective, comparative, observational study was conducted, assigning patients with confirmed onychomycosis to one of three treatment groups: nitric acid, Nd:YAG 1064 nm laser, or combination therapy. Clinical and mycological cure rates, mean time to clinical resolution, changes in Onychomycosis Severity Index [OSI] scores, and mycological relapse rates were assessed over a 12-month follow-up. Results: All three groups demonstrated significant improvement in both clinical and mycological cure rates, with the combination therapy yielding the most favorable outcomes in terms of response speed and durability. Laser and nitric acid monotherapies were also effective, though associated with lower cure rates and longer times to resolution. The relapse rate was lowest in the combination group. Conclusions: The combination of nitric acid and Nd:YAG laser appears to be a more effective therapeutic option for Trichophyton rubrum onychomycosis, offering superior clinical and mycological outcomes compared to monotherapies, with faster resolution and lower relapse rates. These findings suggest that combination therapy may optimize the management of this challenging nail infection. Full article

Skin scars represent a complex therapeutic challenge, with significant functional, aesthetic, and psychological implications. Despite advances in laser therapy, monotherapy has significant limitations, particularly for patients with complex scars with atrophic, hypertrophic, vascular, and pigmentary components. The combined use of multiple laser sources, in sequential or simultaneous mode, allows for the selective targeting of specific tissue components and improves clinical efficacy while maintaining a good safety profile. This narrative review critically analyses the available evidence on combination therapies for atrophic, hypertrophic, keloid, and post-surgical and burn scars. Protocols combining ablative lasers (CO₂, Er:YAG), non-ablative lasers (1540–1550 nm), vascular lasers (PDL, Nd:YAG) and intense pulsed light (IPL) are reported. Possible integrations with adjuvant techniques, such as radiofrequency, platelet-rich plasma (PRP), and laser-assisted drug delivery, are also mentioned as areas for future development. The available data suggest a promising role for multimodal strategies, but the literature remains limited by small cohorts, heterogeneous protocols, and short follow-up periods. Although adverse events are generally mild and transient, typically involving erythema, oedema, or temporary dyschromia, an awareness of safety considerations remains essential, particularly in higher phototypes and when using ablative modalities. Further prospective and multicentre studies are needed to define standardised protocols and consolidate the role of combination therapies in the management of scars. Full article

Background: To evaluate the short-term effects of a dietary supplement containing curcumin, bromelain, glucosamine, chondroitin sulphate, sodium hyaluronate, type II collagen, and vitamin C on symptomatic vitreous floaters (SVFs) following Nd:YAG laser capsulotomy. Methods: Forty eyes with SVFs on the first postoperative day were randomized into a control group (standard topical therapy, n = 20) and a treatment group (oral supplement plus standard therapy, n = 20). Outcomes included best-corrected visual acuity (BCVA), contrast sensitivity (CS), and subjective scores from a non-standardized questionnaire on floater perception (QS1), interference with daily activities (QS2), and foreign body sensation (QS3). Objective evaluation was performed using two novel ultrasound-based methods: mean number of vitreous peaks (MVP) from A-scans and mean grey intensity (MGI) from B-scan images processed with ImageJ. Results: At 2 months, the treatment group showed greater improvement in CS (Δ = 0.26 LogCS, CI, 0.14–0.38; p < 0.01), QS1 (Δ = 1.10; 95% CI, 0.60–1.60; p < 0.01), QS2 (Δ = 0.90; 95% CI, 0.40–1.40; p < 0.01), QS3 (Δ = 0.90; 95% CI, 0.44–1.36; p < 0.01), MVP (Δ = 1.10; 95% CI, 0.60–1.60; p < 0.01), and MGI (Δ = 12.89 units; 95% CI, 7.84–17.93; p < 0.01). BCVA was comparable between groups (p = 0.478). Conclusions: Short-term dietary supplementation with vitreous-specific nutrients is well tolerated and associated with improvements in reducing SVFs and foreign body sensations after Nd:YAG capsulotomy and may represent a promising non-invasive therapeutic option. Full article

Background/Objectives: This systematic review aimed to evaluate and summarize the available evidence on the effects of light-based applications, including laser irradiation on fibroblast responses to zirconia surfaces. Methods: A comprehensive electronic search was performed in PubMed, Scopus, Web of Science, Embase, and WorldCat databases. After duplicate removal and eligibility screening, 17 studies met the inclusion criteria. Only in vitro and animal studies assessing fibroblast behavior on zirconia after light- or laser-based surface irradiation were included. Due to heterogeneity in study designs and parameters, data were qualitatively synthesized. Results: All included studies confirmed the biocompatibility of laser-modified zirconia surfaces. Various laser systems—including Er:YAG, Er,Cr:YSGG, Nd:YAG, diode, excimer, and femtosecond lasers—were investigated. Most studies reported enhanced fibroblast adhesion, proliferation, and cytoskeletal organization compared with untreated controls. Two of the included studies demonstrated an antibacterial effect of erbium lasers treatment on zirconia surfaces. However, outcomes varied depending on the laser parameters, irradiation energy, and zirconia type used. Conclusions: Laser-based surface modification of zirconia appears safe and biocompatible, with evidence indicating favorable effects on fibroblast adhesion, proliferation, and organization. While these findings are promising for optimizing soft-tissue integration around zirconia implant abutments, further standardized and long-term studies are necessary to determine optimal laser settings and confirm clinical applicability. Full article

Nanosecond-pulsed Nd:YAG laser ablation was investigated as a method for removing Al Ti-based hard coatings deposited on WC–Co hardmetal inserts. Systematic variation in laser parameters identified conditions for complete coating removal while preserving substrate integrity. The laser was operated at 532 nm, under a range of fluences (0.1–11.7 J/cm²), pulse delays (20–180 µs), and pulse numbers (1–300). LIBS qualitative monitoring enabled precise ablation progress by identifying Ti, Al, and O layers, and later the detection of Co and W signals. Scanning electron microscopy (SEM/EDS) and optical profilometry confirmed that 5–10 pulses at intermediate delays (60–80 µs, 4.8–7.1 J/cm²) provided complete removal of ~18 µm-thick coatings while maintaining substrate integrity. In contrast, higher energies and excessive pulses caused localized melting and surface irregularities. These results demonstrate that Nd:YAG laser ablation, especially when coupled with LIBS, offers a precise, fast, and environmentally alternative to conventional chemical stripping methods for the refurbishment and recycling of cutting tools. Full article

In this study, a kW-level high-power Nd:YAG nanosecond laser was adopted to eliminate a corrosion layer on a 304L stainless steel (SS304L) surface. Four different laser cleaning (LC) processes with various hatch distances and loop counts were adopted. The energy-dispersive X-ray spectroscopy (EDX) analysis revealed that the corrosion layer was successfully eliminated via the LC process. However, the electron probe X-ray microanalysis (EPMA) analysis confirmed that a Cr-based oxide layer with a thickness of a few micrometers had developed on the surface of SS304L by the LC process. Moreover, Cr-depleted regions were generated in the subsurface owing to the Cr consumption for oxide layer development. The surface temperature during the LC process strongly affected the thickness of oxide layers. The oxide layer and Cr-depletion formation can affect the subsequent manufacturing processes, including welding and molding. Moreover, those can influence the materials’ properties themselves, where the laser-cleaned workpieces may be used. Therefore, it is critical to characterize the relation between LC process parameters and microstructural alteration. Full article

The NELIPS acronym stands for Nano-Enhanced Laser-Induced Plasma Spectroscopy. Within this framework, the temporal variation in the enhanced plasma emissions from pure nanomaterials with respect to corresponding bulk materials was monitored as a function of delay time in the range from 1 to 5–11 μs. Six different pure nanomaterials were employed including silver, zinc, aluminum, titanium, iron, and silicon. Radiation from pulsed Nd: YAG laser at wavelength 1064 nm was used to induce both bulk and pure nanomaterial plasmas under similar experimental conditions. Plasma emissions from both targets were monitored via optical emission spectroscopy technique (OES). The spectral line intensities (Signal-To-Noise ratio S/N) from the pure nanomaterial plasma turns out to decline in a constant logarithmic manner but at a slower rate than that from the corresponding bulk material plasma. Consequently, the measured average enhanced emission from different nanomaterials features an increase in an exponential manner with delay time. This trend of increase was accounted for via mathematical elaboration of enhanced emission based on the measured Signal-To-Noise data. Plasma parameters (electron density and temperature) were precisely measured at each delay time as well. Full article

A high-power, long-pulse-width acousto-optical Q-switched 1064 nm laser based on a multi-pass cavity (MPC) is reported in this paper. First, a plano-concave MPC structure satisfying the Q-preserving configuration was designed and introduced into an acousto-optical Q-switched plano-plano cavity Nd:YAG laser, extending the original laser cavity length by 1200 mm. The laser achieved a maximum average output power of 123.6 W with a repetition rate of 10 kHz. At this power level, the laser pulse width was broadened to 157.5 ns, which can be compared to 82.5 ns without the MPC structure, achieving a broadening ratio of 90.9%. The beam quality factors were $M_x^2$ = 10.75 in the horizontal direction and $M_y^2$ = 11.37 in the vertical direction. The experimental results demonstrate that inserting an MPC into the cavity is an effective method for broadening the pulse width of nanosecond lasers. Full article

Introduction: Penile cancer is rare but rising in incidence. Any optimal treatment must balance oncologic control with preservation of sexual and urinary function. Objectives: To evaluate sexual function, patient satisfaction, and oncologic outcomes after carbon dioxide (CO₂), neodymium-doped yttrium aluminum garnet (Nd:YAG), and thulium-doped yttrium aluminum garnet (Tm:YAG) laser therapies for penile cancer. Methods: A systematic review was conducted in accordance with PRISMA 2020. We searched PubMed, Embase, Scopus, Google Scholar, ScienceDirect, ClinicalTrials.gov, and conference proceedings from January 2000 to 5 February 2025 for observational studies reporting sexual function after laser therapy. Risk of bias was assessed with the Newcastle–Ottawa Scale (NOS) and certainty of evidence with Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Results: Eleven studies comprising 593 patients were included, mostly carcinoma in situ or T1. Local recurrence occurred in 6–19% of patients with Tis/T1 and 17–42% in ≥T2. Across laser types, 59–72% of patients retained erectile function, 50–100% reported sexual satisfaction, and 80–100% reported satisfaction with the cosmetic outcomes, with some degree of variation. Reports on libido and orgasm were heterogeneous and generally unvalidated. General patient satisfaction was high but often assessed using non-validated instruments. Conclusions: Laser therapy is a reasonable penile-sparing option for Tis/T1 disease, but mandates strict surveillance. Data are insufficient to support its use for ≥T2 tumors. Laser therapy generally preserves sexual function, but heterogeneous and non-standardized reporting limits firm conclusions. Prospective studies with standardized patient-reported outcome measures are needed. Full article

Background: Kaposi sarcoma (KS) is a human herpesvirus-8-associated vascular malignancy with four subtypes. Although several local therapies are available for cutaneous lesions, no standard treatment exists. Laser therapy is a minimally invasive treatment option; however, its efficacy and safety remain unclear. Objectives: To systematically review and analyze the available literature on the efficacy and safety of laser-based treatment protocols for cutaneous KS lesions. Methods: A comprehensive literature search was conducted up to August 2025 to identify randomized controlled trials, observational studies, and case series with ≥3 patients who received laser therapy for cutaneous KS. Data on patient and disease characteristics, laser protocols, outcomes and adverse events were extracted from the included studies. Results: Eight studies involving 79 patients with 371 treated lesions were included in this systematic review. The reported outcome rates varied greatly between different modalities, with inconsistent outcome definitions. No recurrence was reported in seven studies, whereas the condition in all cases in the eighth study recurred. Overall, laser therapy was well tolerated with minimal adverse effects, including mild atrophic scarring, transient post-inflammatory changes, and hyperpigmentation. Six studies were eligible for meta-analysis, yielding a pooled significant response rate of 88% (95% CI: 44.1–98.6%, I² = 86.3%). Conclusions: Available data indicate that laser therapy may represent a safe and effective option for cutaneous KS, particularly Nd:YAG, which demonstrated good efficacy with low recurrence rates; however, further research is required to define its efficacy more precisely and to standardize treatment protocols. Full article