Search Results (36)

Background/Objectives: The goal of this study was to show the consistency between the inflammatory and anti-inflammatory response in the early postoperative period after corneal refractive surgery (LASIK and PRK), represented by the levels of specific cytokines in the tear film. Materials/Methods: A total of 68 myopic eyes (31 in the LASIK and 37 in the PRK group) had 3 samples of tear film taken, one before surgery (t₀), another 1 h after surgery (t₁) and the third 24 h after surgery (t₂). The tear samples were then analyzed by flow cytometry in order to determine the levels of pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IFN-γ, TNF-α) and the levels of anti-inflammatory cytokines (IL-4, IL-10). Results: A statistically significant positive correlation was found between the concentrations of all pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IFN-γ, TNF-α) and all anti-inflammatory cytokines (IL-4, IL-10), respectively, for both t₁ and t₂ in the group of eyes that underwent LASIK. In the PRK group, there was a statistically significant positive correlation for all cytokines (pro-inflammatory and anti-inflammatory) at t₁; however at t_2, there was no correlation between IL-1β and IL-10, IL-6 and IL-10, IL-8 and IL-10, and IFN-γ and IL-10. In contrast, for other correlations between pro-inflammatory and anti-inflammatory cytokines in the same observation time (t₂), a positive correlation was observed. Conclusions: There is a consistency between the inflammatory and anti-inflammatory responses in the early postoperative period after refractive surgery, which persists longer after LASIK compared to PRK. This difference may explain the different clinical courses in patients after undergoing these procedures. Full article

Background/Objectives: To evaluate the monocular and binocular visual outcomes for patients who underwent PRESBYOND Laser Blended Vision (LBV) surgery. Methods: A total of 46 patients participated in this study (mean age 47.5 yrs ± 4.7) with various refractive errors. Patients were treated using the MEL 90 excimer laser to correct their refractive errors. The patients were asked to attend follow-up sessions at intervals of 1, 3, and 6 months. A self-developed binary (Yes/No) satisfaction survey was then conducted at the end of the 6-month visit. Results: The mean preoperative spherical equivalent for the distance eyes was −0.42 ± 1.53, and for the near eyes was −0.4 ± 1.76. The mean logMAR for the uncorrected distance visual acuity after treatment and follow-up at one month, three months, and six months was 0.016, 0.037, and 0.028 (20/20 to 20/22 range), respectively. After treatment, 81% of patients achieved 20/22.5 vision or better, and 94% achieved 20/25 vision or better. For near vision, 100% of patients reached J2 print. After treatment, 97% of patients achieved 20/25 or better at distance and J2 or better at near. Patient satisfaction was 92%, with only 8% of patients reporting dissatisfaction. Conclusions: This protocol has demonstrated stable, well-tolerated, effective, and acceptable results in patients with presbyopia. The safety and efficacy of the procedure were demonstrated, with strong outcomes. Full article

In this work, we demonstrate a functional and previously insufficiently explored route for converting cyclic olefin copolymer (COC) TOPAS^® thin films into antibacterial hybrid materials through a combination of solvent casting, plasma activation, noble-metal sputtering, and subsequent thermal or laser treatment. While COC is already well-known as a transparent, chemically resistant material for pharmaceutical and optical applications, its coupling with post-treated noble-metal nanostructures for antibacterial functionality has not been systematically described. The main contribution of this study lies in showing that COC can serve not only as a passive packaging substrate, but also as an active platform for the formation of biologically relevant surface nanostructures. Compared with previously reported metal/polymer systems, the present work provides clear evidence that noble-metal layers on COC undergo substantial structural evolution after thermal and excimer-laser treatment, resulting in regular nanoclustered morphologies. A particularly important finding is the detection of Au particle implantation below the COC surface during sputtering, as revealed by Rutherford backscattering spectrometry, which distinguishes this system from conventional surface-only metal coatings. Furthermore, we show that laser and thermal processing do not merely reshape the deposited layer, but significantly influence the final biological response of the material. Ag-based structures showed strong bactericidal behavior against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. The prepared samples were comprehensively characterized by AFM, DSC, RBS, SEM, and TGA, and their roughness and wettability were also evaluated, enabling direct correlation between physicochemical changes and antibacterial performance. These results introduce a new strategy for upgrading conventionally used pharmaceutical COC materials into multifunctional surfaces with added antibacterial value. 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

Purpose: The aim of this paper is to study the visual outcomes, changes in higher order aberration (HOA) and corneal densitometry after debridement and excimer laser phototherapeutic keratectomy (PTK) for the treatment of Salzmann nodular degeneration (SND). Methods: This monocentric study includes 69 eyes from 54 patients who underwent debridement and PTK for SND (mean follow-up time of 447.1 ± 597.7 days post-operatively). The following parameters were measured before and after PTK: best corrected visual acuity (BCVA) in logMAR, sphere, cylinder, calculated spherical equivalent (SPHQ), mean and maximum refractive power, astigmatism, HOA, corneal density and thickness. Patients were divided into two cohorts depending on additional visual acuity limitations (VAL). Results: Mean visual acuity improvement was 0.16 ± 0.21 logMAR (p < 0.001), independent of additional VAL, and was associated with normalization of the cornea (hyperopic reduction by 2.13 ± 2.60 dpt, p < 0.001), reductions in cylinder (1.49 ± 2.44 dpt, p < 0.001) and corneal astigmatism (3.01 ± 3.39 dpt, p < 0.001). HOA was reduced by 0.77 ± 1.11 µm (p < 0.001) and corneal density by 6.08 ± 16.45 gray scale units (GSUs) in the center (p = 0.019) and by 9.32 ± 12.08 GSUs in the mid-periphery (p < 0.001). Haze occurred in 26.1% of patients (15.9% mild; 10.1% moderate). Re-PTK was necessary in 5.8%. Conclusions: PTK is a low-complication method for visual improvement in patients with SND, regardless of additional VAL, and is associated with a normalization of corneal parameters. HOA, corneal density and K_max were reduced significantly and showed a correlation with visual acuity, implying that these objective parameters may have a good predictive value for visual acuity. Full article

Background/Objectives: Although both the MEL90 (Carl Zeiss Meditec AG, Jena, Germany) and WaveLight EX500 (Alcon Laboratories, Inc., Fort Worth, TX, USA) are two widely used excimer lasers, comparisons between the two remain limited. This study evaluates visual and refractive outcomes from the U.S. Food and Drug Administration (FDA) premarket approval trials of these platforms in the treatment of myopia with and without astigmatism, hyperopia with and without astigmatism, and mixed astigmatism. Methods: Clinical outcomes from FDA premarket approval trials were compared between the recently approved MEL90 and the WaveLight (now termed EX500) excimer lasers. Results: A total of 714 eyes (358 patients) from MEL90 and 1353 eyes (706 patients) from EX500 were analyzed up to 6 months postoperatively. In the hyperopia/hyperopic astigmatism cohort, the EX500 demonstrated greater efficacy relative to MEL90, with more eyes achieving a postoperative uncorrected distance visual acuity (UDVA) of 20/20 or better (48.6% vs. 68.7%, respectively; p < 0.001). In both the MEL90 and EX500, at least 85% of eyes with myopia/myopic astigmatism and 68% with mixed astigmatism achieved a postoperative UDVA of 20/20 or better. For all refractive cohorts, more than 95% of eyes achieved a UDVA of 20/40 or better at 6 months (all p > 0.05). The EX500 was more likely to demonstrate an improvement of more than two lines of UDVA compared to baseline CDVA (all p < 0.05). In contrast, the MEL90 showed greater predictability of spherical equivalent within ±0.50 D and ±1.00 D for the hyperopia/hyperopic astigmatism cohort (both p = 0.007), as well as within ±0.50 D for the myopia/myopic astigmatism cohort (p < 0.001). Postoperatively, both platforms were associated with decreased glare and halos, although findings were variable in the EX500 mixed astigmatism cohort. Conclusions: Both excimer lasers demonstrated safe and effective outcomes that exceed the threshold set by the FDA. Full article

Background: Post-traumatic corneal wounds that require suturing are quite common; they reduce corneal transparency and cause corneal distortion, leading to corneal astigmatism and higher-order aberrations. Excimer laser treatment can be a potentially beneficial intervention for such wounds. The observation aimed to evaluate the effectiveness of topography-guided custom ablation treatment (TCAT) in patients with corneal injuries. Methods: This observation included three patients with corneal penetrating trauma (full-thickness corneal scar) and one patient with corneal blunt trauma, i.e., a non-penetrating injury with corneal laceration (partial-thickness corneal scar). This cohort study was conducted from July 2021 to August 2023. After first-stage treatment (stabilization of the post-traumatic visual defect confirmed by refraction and topography examination, corneal healing, and improvement of the corneal scar), the patients underwent the second-stage treatment, i.e., TCAT with a 20 to 45 s application of mitomycin C solution to avoid haze induction. After TCAT, the uncorrected distance visual acuity (UDVA) and best-corrected distance visual acuity (BCVA) were measured. Refractive astigmatism was assessed using autorefractometry. Topographic astigmatism was analyzed using corneal topography and pachymetry. The root mean square (RMS) of the higher-order aberration was calculated using Zernike coefficients. The patients’ corneal healing and refractive changes were monitored. Results: All patients were monitored for corneal healing and refractive changes and underwent the same second-stage treatment, which utilized TCAT to regularize the corneal surface and reduce higher-order aberrations (HOAs). The UDVA of patients 1, 2, 3 and 4 improved by 3, 7.5, 4 and 6 rows (Snellen chart), respectively. The resultant UDVA was 1.0, 0.9, 0.7 and 1.2, while BCVA was 1.0, 1.2, 1.0, and 1.5, respectively. Conclusions: TCAT regularized the patients’ corneal surfaces and reduced HOAs. We, therefore, conclude that TCAT may be a beneficial second-stage treatment for corneal trauma-induced astigmatism. Full article

Objective: To conduct a systematic review of the literature evaluating the efficacy of the 308 nm excimer lamp in comparison to narrowband ultraviolet B (NB-UVB) and the 308 nm excimer laser for inducing repigmentation in vitiligo. Methods: A comprehensive search was performed in PubMed, Embase, Cochrane Library, Scopus, Web of Science, and LILACS databases, as well as in gray literature sources including Google Scholar, OpenGrey, Livivo, and ProQuest. Risk of bias was assessed independently by two blinded reviewers using the Cochrane RoB 2 tool, with disagreements resolved by a third reviewer. The primary outcome was the degree of repigmentation. Results: Of 3825 records identified, four randomized controlled trials met the inclusion criteria. The findings suggest that the 308 nm excimer lamp provides superior repigmentation outcomes compared to NB-UVB and demonstrates comparable efficacy to the 308 nm excimer laser. Conclusions: Phototherapy using the 308 nm excimer lamp appears effective in promoting repigmentation in vitiligo patients and is associated with minimal adverse effects. Nevertheless, variations in treatment protocols and potential bias across studies warrant cautious interpretation of the results. Full article

Objectives: To report a novel application within the USA of excimer ablation for the normalization of central corneal refractive irregularity, combined with higher fluence CXL in the effective management and visual rehabilitation of progressive keratoconus. Methods: 17 consecutive cases with progressive keratoconus were treated with corneal surface excimer laser ablation normalization using topography-guided (Contura) myopic ablation for customized corneal re-shaping with a 6 mm optical zone. The epithelial removal was accounted for by adding a −2.75 diopter correction to this topography-guided normalizing surface ablation followed by a second wavefront-optimized hyperopic excimer treatment of +2.75 diopters also with a 6 mm optical zone. The two sequential excimer ablations applied on the intact epithelium were followed by corneal crosslinking (CXL). Visual acuity, refraction, and keratoconus documentation via keratometry, topography, and pachymetry, as well as endothelial cell density were evaluated over 36 months. Results: Keratoconus stabilized in all cases. The severity and stage of keratoconus determined by the Amsler–Krumeich criteria improved for the OD from an average of 2.2 to 1. The median UDVA showed marked improvement at one-year follow-up (all values in LogMAR), from 0.8 preoperative to 0.3 at 12 months, and was stable through the 3 years at 0.3. The median CDVA increased from 0.5 to 0.1 at 1 year and was stable at 0.1 at 3 years. The average minimal corneal thickness decreased from 466 μm to 396 μm, as recorded the first year postoperatively, and then slightly increased to 405 μm at the 3-year follow-up. Conclusions: We introduce herein the initial clinical data for the use of a novel, off-label therapeutic excimer laser surface ablation application. It was designed to perform both epithelial removal and anterior corneal stroma reshaping and combined with CXL to apply the Athens Protocol CXL with US excimer laser-approved specifications. Full article

Background: The rate of in-stent restenosis (ISR) is decreasing; however, it is still a challenge for contemporary invasive cardiologists. Therapeutic methods, including drug-eluting balloons (DEBs), intravascular lithotripsy, excimer laser coronary atherectomy, and imaging-guided percutaneous coronary intervention (PCI) with drug-eluting stents (DES), have been implemented. Patients with diabetes mellitus (DM) are burdened with a higher risk of ISR than the general population. Aims: DM-Dragon is aimed at evaluating the clinical outcomes of ISR treatment with DEBs vs. DES, focusing on patients with co-existing diabetes mellitus. Methods: The DM-Dragon registry is a retrospective study comprising data from nine high-volume PCI centers in Poland. A total of 1117 patients, of whom 473 individuals had DM and were treated with PCI due to ISR, were included. After propensity-score matching (PSM), 198 pairs were created for further analysis. The primary outcome of the study was target lesion revascularization (TLR). Results: In DM patients after PSM, TLR occurred in 21 (10.61%) vs. 20 (10.1%) in non-diabetic patients, p = 0.8690. Rates of target vessel revascularization (TVR), target vessel myocardial infarction, device-oriented composite endpoint (DOCE), and cardiac death did not differ significantly. Among diabetic patients, the risk of all-cause mortality was significantly lower in the DEB group (2.78% vs. 11.11%, HR 3.67 (95% confidence interval, CI) [1.01–13.3), p = 0.0483). Conclusions: PCI with DEBs is almost as effective as DES implantation in DM patients treated for ISR. In DM-Dragon, the rate of all-cause death was significantly lower in patients treated with DEBs. Further large-scale, randomized clinical trials would be needed to support these findings. Full article

Background: Acute keratoconus (acute KC), which affects approximately 1.6–2.8% of keratoconus (KC) patients, is a pathological condition of the cornea characterized by stromal edema due to entry of aqueous humor through a tear in Descemet’s membrane. Methods: We present a novel combination of surgical procedures that allows swifter visual recovery in a consecutive, retrospective case series. The new surgical procedure for acute KC consists of a combination of Muraine corneal sutures to smooth the corneal curvature and Excimer laser-assisted penetrating keratoplasty and was performed in six acute KC patients from 2019 to 2022 at the Department of Ophthalmology, University Hospital of Martin-Luther-University Halle-Wittenberg (UMH), Germany. We monitored data on preoperative status, operative details, intraoperative and postoperative complications and visual outcomes were analyzed. Results: The mean age was 41.5 ± 13.5 years (3 OD, 3 OS). Neurodermatitis was present in 3 patients (50%). All patients received significant visual benefits from the procedure. Preoperative BCVA was hand motion (logMAR 3.0) in all patients; postoperatively, BCVA improved significantly logMAR 0.03 ± 0.09 [range: 0.2–0.4; p < 0.001, FUP 20+/−10 months). Visual acuity remained stable throughout the roughly biannual follow-ups. One patient developed endothelial graft rejection after 2 years. During the last examination, all eyes had clear grafts and stable curvatures, K1 and K2 being 42.43 ± 4.17 D and 44.95 ± 4.07 D, respectively, and mean corneal astigmatism was 2.61 ± 1.74 D. The thinnest corneal thickness was 519 ± 31 µm. A graft size of 8.0 × 8.1 mm was the most beneficial. Conclusions: in patients with acute KC and hydrops, a penetrating keratoplasty with Muraine corneal sutures is successful in terms of graft clarity and visual outcome. Combining the procedures allows quicker visual recovery. Patients with a history of neurodermatitis should have preoperative and postoperative dermatologic treatment and close follow-up for possible complications. Full article

In this study, a KrF excimer laser with a high-absorption coefficient in metal oxide films and a wavelength of 248 nm was selected for the post-processing of a film and metal oxide thin film transistor (MOTFT). Due to the poor negative bias illumination stress (NBIS) stability of indium gallium zinc oxide thin film transistor (IGZO-TFT) devices, terbium-doped Tb:In₂O₃ material was selected as the target of this study. The XPS test revealed the presence of both Tb³⁺ and Tb⁴⁺ ions in the Tb:In₂O₃ film. It was hypothesized that the peak of the laser thermal effect was reduced and the action time was prolonged by the f-f jump of Tb³⁺ ions and the C-T jump of Tb⁴⁺ ions during the laser treatment. Studies related to the treatment of Tb:In₂O₃ films with different laser energy densities have been carried out. It is shown that as the laser energy density increases, the film density increases, the thickness decreases, the carrier concentration increases, and the optical band gap widens. Terbium has a low electronegativity (1.1 eV) and a high Tb-O dissociation energy (707 kJ/mol), which brings about a large lattice distortion. The Tb:In₂O₃ films did not show significant crystallization even under laser energy density treatment of up to 250 mJ/cm². Compared with pure In₂O₃-TFT, the doping of Tb ions effectively reduces the off-state current (1.16 × 10⁻¹¹ A vs. 1.66 × 10⁻¹² A), improves the switching current ratio (1.63 × 10⁶ vs. 1.34 × 10⁷) and improves the NBIS stability (ΔV_ON = −10.4 V vs. 6.4 V) and positive bias illumination stress (PBIS) stability (ΔV_ON = 8 V vs. 1.6 V). Full article

Background and objectives: The aim of the research was to investigate the differences in the concentrations of IL-12, IL-4, IL-10, and IFN-γ in tears after LASIK and PRK procedures. Materials and methods: The study included 68 myopic eyes up to −3.0 D refractive spherical equivalent, divided into two groups: Group 1 LASIK (n = 31) and Group 2 PRK (n = 37). Three tear samples were taken from each eye: immediately before the procedure (t₀), 1 h after the procedure (t₁), and 24 h after the procedure (t₂). The concentrations of IL-12p70, IL-4, IL-10, and IFN-γ in the tear samples were determined by flow cytometry. Participants were not taking anti-inflammatory therapy 24 h after the procedure. Results: IL-4 levels 1 h after treatment did not differ between LASIK and PRK (p = 0.990), while 24 h after PRK there was a significant decrease in IL-4 levels (p < 0.05), but not after LASIK (p = 0.476). In both the LASIK (p < 0.05) and PRK (p < 0.05) groups, there is an increase in IL-10 concentrations 1 h after treatment, which persists 24 h after LASIK (p < 0.05) but not after PRK (p = 0.081). There is an increase in IL-12p70 concentration 1 h after treatment in both the LASIK (p < 0.001) and PRK groups (p < 0.001). There is also an increase in IL-12p70 concentration 24 h after PRK (p < 0.005), but not after LASIK (p = 0.775). Conclusions: IL-4 concentration shows a significantly higher value in the LASIK group than in the PRK group after 24 h. IL-10 and IL-12p70 levels increase one hour after surgery in both groups. After 24 h, the IL-10 levels remain elevated in the LASIK group, and the IL-12p70 levels remain elevated in the PRK group. Thus, LASIK and PRK procedures show different inflammatory dynamics. Full article

Here, we aimed to achieve exposure of a nanodiamond layer to a high-energy excimer laser. The treatment was realized in high-vacuum conditions. The carbon, in the form of nanodiamonds (NDs), underwent high-temperature changes. The induced changes in carbon form were studied with Raman spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction (XRD) and we searched for the Q-carbon phase in the prepared structure. Surface morphology changes were detected by atomic force microscopy (AFM) and scanning electron microscopy (SEM). NDs were exposed to different laser energy values, from 1600 to 3000 mJ cm⁻². Using the AFM and SEM methods, we found that the NDs layer was disrupted with increasing beam energy, to create a fibrous structure resembling Q-carbon fibers. Layered micro-/nano-spheres, representing the role of diamonds, were created at the junction of the fibers. A Q-carbon structure (fibers) consisting of 80% sp³ hybridization was prepared by melting and quenching the nanodiamond film. Higher energy values of the laser beam (2000 and 3000 mJ cm⁻²), in addition to oxygen bonds, also induced carbide bonds characteristic of Q-carbon. Raman spectroscopy confirmed the presence of a diamond (sp³) phase and a low-intensity graphitic (G) peak occurring in the Q-carbon form samples. Full article

In the early 2000s, solid-state lasers emerged as an alternative technology to excimer systems in refractive surgery. Despite some technological limits at the time, good clinical results could be achieved with solid-state laser systems. This prospective case series reports clinical outcomes of five eyes treated with a newly developed solid-state laser system (AquariuZ) in three patients. Patients underwent preoperative examination, including corneal topo-and tomography, aberrometry, and confocal microscopy. All patients received a femtosecond LASIK with the Ziemer LDV Z8, a refractive treatment with the AquariuZ solid-state ablation laser, and were then followed up for a period of up to 12 months. The applied aspheric optimized profiles did not induce higher-order aberrations nor spherical aberration in any of these operated subjects. No eye lost BCVA lines throughout the duration of the follow-up. Six months after surgery, the safety index of patient 1 was 5, and for patients 2 and 3, it equaled 1. Confocal laser microscopy imaging findings were comparable to those seen typically for excimer lasers. The obtained results are encouraging and confirm that the new solid-state laser system is safe. Full article