Search Results (108)

Background/Objectives: The technique used for flap creation in laser in situ keratomileusis (LASIK) may influence postoperative optical quality and visual outcomes. This prospective randomized paired-eye study compared higher-order aberrations (HOAs) and visual acuity outcomes following femtosecond laser-assisted versus mechanical microkeratome-assisted LASIK. Materials and Methods: Forty-four patients (88 eyes) underwent bilateral LASIK. In each patient, one eye was randomly assigned to high-frequency femtosecond laser flap creation (Femto LDV), and the fellow eye to mechanical microkeratome flap creation (Amadeus II). Inclusion criteria were stable refraction, central corneal thickness ≥ 520 µm, and normal corneal topography. HOAs were measured using Hartmann–Shack wavefront aberrometry over a 6 mm pupil diameter. Uncorrected and corrected distance visual acuity (UDVA and CDVA) were evaluated preoperatively and postoperatively at 1 day, 1 week, and 1, 3, and 6 months. Results: Both techniques induced significant postoperative changes in specific Zernike coefficients and an increase in total HOA root mean square (RMS) values (p < 0.05). A reduction in spherical aberration (Z4,0) was observed in both groups, while technique-specific changes were noted in individual aberration components including an increase in horizontal trefoil (Z3,3) in the femtosecond and a decrease in horizontal coma (Z5,1) in the microkeratome group. However, paired-eye comparisons revealed no statistically significant differences in total HOA six months postoperative. Despite comparable aberrometric outcomes, femtosecond-treated eyes demonstrated significantly better UDVA and CDVA at all postoperative time points (p < 0.05). Conclusions: Femtosecond laser-assisted and microkeratome-assisted LASIK resulted in comparable changes in higher-order aberrations, despite differing pattern in individual aberration components. The observed differences in visual acuity outcomes were not reflected in wavefront metrics, suggesting that postoperative visual performance may be influenced by factors. Full article

Members of Fusarium oxysporum species complex (FOSC) and Fusarium solani species complex (FSSC) are common etiologic agents of opportunistic mycoses. Their hyphae grow via apical extension followed by invasion of host epithelial surfaces, particularly corneal and epithelial tissues. Thigmotropism is the contact-sensing response of these growing hyphae to change the direction of their apical growth in response to changes in the topography of their contacted surfaces, such as clefts between adjacent host cells. Investigations of fungal thigmotropism among etiologic agents of opportunistic mycoses are sparse. In this study, we assessed thigmotropic capacities of 10 fusarial strains. Thigmotropic activity was quantified using a chemotaxicell system followed by scanning electron microscopy (SEM). Isolates belonging to the FSSC had significantly greater rates of thigmotropism than FOSC strains (p < 0.0001). In summary, this work offers a creative method to assess thigmotropism, a crucial aspect of fungal pathogenesis, and, secondly, demonstrates potent thigmotropic capacities of fusarial isolates belonging to the FSSC. Full article

Background/Objectives: To evaluate changes in corneal topography and densitometry (CD) 3 months after accelerated corneal collagen crosslinking (CXL) for keratoconus and to investigate influencing factors. Methods: Twenty-one (41 eyes) patients with KC who underwent accelerated epithelium-off CXL were included in this retrospective observational study; preoperative and 3-month postoperative CD and corneal topographic parameters measured by Pentacam HR were collected. The changes in corneal topographic parameters and CD before and after CXL were subsequently compared, and the correlation between age, corneal topographic parameters and CD changes was analysed. Results: Except for TCT (p = 0.026), no significant changes were observed in topographic parameters (p > 0.05). There was a significant increase in total CD (tCD), CD 0–2 mm and CD 2–6 mm from the whole, anterior and central corneal layers after CXL compared to pre-operation (p < 0.05). The results of the correlating factors showed that age was positively associated with changes in tCD, CD 0–2 mm, and CD 2–6 mm from the whole, anterior and central corneal layer (p < 0.05), which was fully consistent with the regions treated by CXL. Other factors showed only marginal associations and were not consistent with the regions treated by CXL. Conclusions: An increase in CD can be observed in patients with KC at 3 months after undergoing accelerated CXL, and this is particularly focused on the 0–2 mm and 2–6 mm regions of the anterior and central corneal layers. The degree of change in CD was influenced by age, which may suggest differences in corneal response to CXL in KC of different ages. Full article

Background/Objectives: To evaluate the associations between corneal topographic irregularity, higher-order aberrations (HOAs), and posterior segment structural and microvascular parameters in keratoconus using optical coherence tomography (OCT) and OCT angiography (OCTA). Methods: In this cross-sectional study, 81 eyes with keratoconus and 60 healthy control eyes underwent corneal topography and wavefront analysis, spectral-domain OCT with enhanced depth imaging, and OCTA. Retinal layer thicknesses, choroidal thickness and area metrics, choroidal vascularity index (CVI), and OCTA-derived vascular parameters were analyzed. Associations were assessed using Spearman correlation analysis with false discovery rate (FDR) correction. Results: Compared with controls, keratoconus eyes showed significantly increased corneal curvature, corneal irregularity indices, and HOAs (all p < 0.001). Structural OCT analysis demonstrated preserved inner retinal layers, whereas outer nuclear layer thickness was reduced (p < 0.001) and overall outer retinal layer thickness was increased (p = 0.005). Choroidal thickness and both total and luminal choroidal areas were significantly greater in keratoconus eyes (all p ≤ 0.011), while CVI did not differ between groups (p > 0.05). OCTA revealed reduced superficial capillary plexus vessel density at the whole image and perifoveal regions (all p < 0.001), whereas deep capillary plexus and foveal avascular zone metrics were largely preserved. Correlation analyses identified only weak and inconsistent associations between corneal parameters, HOAs, and posterior segment measurements, none of which remained statistically significant after FDR correction. Conclusions: Despite pronounced anterior segment deformation and optical degradation, posterior segment structural and microvascular alterations in keratoconus are limited and weakly related to corneal disease severity. These findings support a predominantly anterior segment centered pathophysiology of keratoconus and highlight the importance of stringent multiple-comparison control in multimodal imaging studies. Full article

Background: Mirvetuximab soravtansine (MIRV) improves outcomes in FRα-positive, platinum-resistant ovarian cancer; however ocular adverse events (OAEs), particularly corneal epithelial toxicity, are frequent and warrant structured ophthalmologic monitoring. Methods: In this retrospective observational study, 31 consecutive patients receiving MIRV for FRα-positive gynecologic malignancies underwent standardized ophthalmic assessments at baseline and prior to each treatment cycle (every 21 days). The protocol included best corrected visual acuity (BCVA), slit-lamp biomicroscopy, anterior-segment optical coherence tomography (AS-OCT), corneal topography, and tear film analysis. OAEs were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) v5.0, based on symptom severity and functional impairment. Results: OAEs occurred in all patients (31/31, 100%), predominantly grade 1–2. Corneal epithelial toxicity was documented in 28/31 patients (90.3%), while no grade ≥ 3 events were observed. Symptoms typically developed 7–14 days after the second infusion. AS-OCT and corneal topography consistently revealed epithelial microcysts and surface irregularities, which were usually detected during scheduled pre-cycle ophthalmologic evaluations. Tear-film instability (break-up time ≤ 5 s) developed in 19/31 patients (61.3%), generally within 10 days after the second infusion, and improved in all but 2 patients (6.5%) following prophylactic lubrication. Transient refractive changes occurred in 28/31 patients (90.3%) and were associated with a temporary BCVA reduction (mean nadir ~20/32 Snellen), followed by recovery during follow-up. Conclusions: MIRV-related ocular alterations are frequent but reversible and clinically manageable. Multimodal imaging combined with functional and refractive assessment provides sensitive markers of corneal epithelial toxicity and supports integrated ophthalmologic monitoring to preserve visual function and maintain oncologic treatment continuity. Full article

Objectives: To investigate the effectiveness of scleral lenses following corneal cross-linking (CXL) in patients with progressive keratoconus. Methods: This retrospective study analyzed patients with keratoconus who underwent CXL and subsequently used scleral lenses for at least one year. A total of 21 patients (23 eyes) with progressive keratoconus were included. CXL was performed using the epithelium-off cross-linking technique following the Dresden protocol. Corneal astigmatism (CA), white-to-white distance, thinnest corneal thickness, and central corneal thickness (CCT) were assessed using corneal topography and tomography. Data were collected before CXL, at one month postoperatively, at the time of scleral lens prescription, and at 1, 3, 6, and 12 months after scleral lens use. Results: The mean age of the patients was 24.6 ± 4.6 years. The baseline uncorrected visual acuity (logMAR) before CXL was 1.05 ± 0.52. The baseline Kmax and CA were 53.01 ± 6.99 and −5.83 ± 3.23 D, respectively. The mean CCT was 444.09 ± 61.82 µm. The mean interval between CXL and scleral lens prescription was 6.75 ± 8.49 months. Following CXL, the Kmean decreased from 49.61 to 45.79 (p = 0.056), Kmax decreased from 53.01 to 51.32 (p = 0.053), and CA decreased from −5.83 to −4.91 D (p = 0.051), albeit statistically non-significant. At the 12-month follow-up after scleral lens prescription, Kmean and Kmax values remained stable, indicating no disease progression. Compared with baseline values before CXL, Kmean, Kmax, and CA were significantly reduced at the 12-month follow-up after scleral lens prescription (p = 0.047, p = 0.049, and p = 0.042, respectively). Scleral lens-corrected visual acuity was significantly better than habitual corrected visual acuity at all follow-up time points. Conclusions: Scleral lens application following CXL was associated with improved corrected visual acuity, and corneal keratometric values remained stable during lens wear. Full article

Background: This study examined spherical and aspherical orthokeratology (Ortho-K) lens designs for myopia control and corneal optical stability over the course of a year. Methods: This retrospective analysis used data from a previously conducted two-centre, single-blind, randomised contralateral-eye clinical study, in which 48 children aged 8 to 15 years wore a spherical Ortho-K lens in one eye and an aspherical lens in the other. Measurements included axial length (AL), best-corrected visual acuity (BCVA), lens decentration, corneal power, and higher-order aberrations over 12 months. Corneal topography was analysed using customised MATLAB code, Zernike fitting and paired inter-eye differences were evaluated with the Wilcoxon signed-rank test. Results: Both lenses exhibited typical Ortho-K reshaping patterns, with central flattening and mid-peripheral steepening. The aspherical lens resulted in slower AL elongation than the spherical lens (p < 0.01). It also produced smaller, more stable treatment zones and less variability in higher-order aberrations. Significant differences between the designs were found for vertical coma (p = 0.006), spherical aberration (p = 0.002), and vertical tilt (p = 0.02). Lens decentration also differed significantly (p < 0.01). Conclusions: Over 12 months, the aspherical Ortho-K lens demonstrated superior myopia control and more stable corneal optics than the spherical lens. Full article

Background and Objectives: Accurate anterior segment measurements are central to intraocular lens (IOL) power calculation and toric planning, yet different optical platforms may yield non-interchangeable values. This study compared keratometry, astigmatism metrics, and ocular biometry obtained with a swept-source OCT biometer (Argos), an optical low-coherence interferometry biometer (Aladdin), and a combined Scheimpflug–Placido topographer (Schwind Sirius). Methods: This is a retrospective observational study (January 2022–June 2024) including eyes undergoing uncomplicated cataract surgery. All eyes were measured in a single session by one examiner. Outcomes included K1, K2, cylinder, astigmatism axis (degrees; device-reported corneal cylinder axis, labeled “Powerful Angle” in the Sirius export), vector components (J0 and J45), and—where available—lens thickness (LT), axial length (AL), anterior chamber depth (ACD), white-to-white (WTW) distance, and central corneal thickness (CCT). Friedman tests assessed 3-device differences, and pairwise comparisons were evaluated using Wilcoxon signed-rank tests (paired data). Results: A total of 170 eyes (102 patients) were analyzed (mean age: 69.12 ± 10.26 years). Significant inter-device differences were detected for K1 (Argos: 43.45 ± 1.64 D; Aladdin: 43.41 ± 1.70 D; overall: p < 0.001; Argos vs. Aladdin: p = 0.019), K2 (Argos: 44.45 ± 1.67 D; Aladdin: 44.34 ± 1.71 D; overall and pairwise: p < 0.001), and cylinder (Argos: −0.83 ± 0.74 D, Aladdin: −0.77 ± 0.76 D; Sirius: −0.68 ± 0.75 D; overall: p < 0.001). “Powerful Angle” differed across devices (p = 0.003) but not between Argos and Aladdin (p = 0.512). J0 (p = 0.277) and J45 (p = 0.084) did not differ significantly. Argos reported higher ACD (3.19 ± 0.42 vs. 3.13 ± 0.41 mm, p < 0.001) and WTW (11.95 ± 0.42 vs. 11.65 ± 0.39 mm, p < 0.001) values than Aladdin. CCT was similar between Aladdin and Sirius (540.27 ± 33.44 vs. 540.47 ± 33.78 µm, p = 0.169). Conclusions: Several keratometric and biometric parameters differed significantly by device, indicating limited interchangeability—particularly relevant for toric and premium IOL planning—while vector astigmatism components and CCT showed better agreement. Full article

Objectives: To characterize the clinical features, corneal topography, and imaging findings of peripheral hypertrophic subepithelial corneal degeneration (PHSCD) in a single-center study and to evaluate potential associations with systemic conditions. Methods: All patients underwent comprehensive ophthalmic examination, anterior segment photography, high-resolution spectral-domain optical coherence tomography (OCT), and corneal topography/tomography. Patient demographics, ocular history, systemic conditions, and corneal parameters were analyzed. Results: Fourteen patients were included in the study (11 females and 3 males). The mean age was 52.6 ± 12.4 years, and the mean best-corrected visual acuity was 0.56 ± 0.23. Five females had Hashimoto’s disease and two had hyperthyroidism. The mean central corneal thickness was 549.4 μm (SD = 71.0 μm), with significant sectoral thickness variations, particularly in the superior-nasal quadrants (SN-IT sector mean difference: 56.4 μm). High-resolution OCT revealed sharply demarcated, hyperreflective fibrosis within the anterior stroma, predominantly in the superior-nasal quadrants, causing corneal flattening with compensatory steepening and astigmatism. Three patients underwent in vivo confocal microscopy, which showed fibrotic acellular tissue adjacent to normal corneal epithelium. Conclusions: PHSCD predominantly affects middle-aged females and presents with characteristic peripheral, subepithelial fibrosis, causing significant corneal thickness variations and astigmatism. The observed association with thyroid disorders, particularly Hashimoto’s disease, suggests a potential immunological component in PHSCD pathogenesis that warrants further investigation. Advanced imaging with OCT and confocal microscopy provides valuable diagnostic information to accurately characterize this rare corneal condition. Full article

Background/Objectives: To evaluate the predictive accuracy of intraocular lens (IOL) power calculation by ray tracing in eyes with previous radial keratotomy (RK). Methods: A consecutive series of eyes with previous RK was retrospectively analyzed. Preoperatively, all eyes underwent optical biometry to measure the axial length (AL) and anterior segment imaging by the MS-39 (CSO), which combines Placido disk corneal topography and anterior segment optical coherence tomography. The built-in ray tracing software was used to calculate the IOL power. For comparative purposes, the results of the Barrett True-K, EVO, Haigis total keratometry, and PEARL-DGS formulas were also investigated. The refractive outcomes were evaluated with Eyetemis. Results: Twenty-four eyes (24 patients) were investigated. The mean AL and keratometry were, respectively, 27.34 ± 2.88 mm and 35.53 ± 3.66 diopters (D). The mean prediction error (PE) was −0.03 ± 0.65 D (range: from −1.30 to +1.64 D). The mean and median absolute errors were 0.52 and 0.48 D, respectively. The percentages of eyes with a PE within ±0.25 D, ±0.50 D, and ±1.00 D were 29.17%, 62.50%, and 87.50%, respectively. A comparison with the other formulas was possible in 20 eyes and did not reveal any statistically significant differences; the percentage of eyes with a PE within ±0.50 D ranged from 50 to 65%. Conclusions: Ray tracing is a relatively accurate solution for calculating the IOL power in eyes with previous RK. Paraxial formulas provide similar outcomes and should be considered in these patients. The refractive outcomes of IOL power calculation in post-RK eyes are still below modern benchmarks for virgin eyes. Full article

Background: This study focuses on the diagnosis and treatment of keratoconus in the early stage and aims to identify the environmental and risk factors that contribute to its progression. Methods: This retrospective investigation was carried out at the University Clinical Center of Kosovo (UCCK) and comprised 131 patients newly diagnosed with keratoconus (KC). All procedures adhered to the Declaration of Helsinki, and the University of Pristina ethics committee approved this study before its initiation (Ref.Nr.104/2023). The confidentiality and anonymity of the surveyed patients were respected. The patients’ data consisted of gender, age, and race. Results: There were significant differences in the K1 distribution between groups, as the normal group (41.4 ± 0.5) was significantly lower than the suspect group (45.0 ± 3.2) and the degree of keratoconus (p < 0.001). There were significant differences in K2 between the groups, as the normal group (44.7 ± 5.1) was significantly lower than the suspect group (47.1 ± 2.8) and the other grades of keratoconus (p < 0.001). There were significant differences between groups regarding Kmax, as the normal group (44.5 ± 3.1) was significantly lower than the suspect group (46.9 ± 1.6) and the other grades of keratoconus (where p < 0.001). Statistically meaningful differences were detected between the groups with respect to subtlety, as the normal group (504.0 ± 27.6) was significantly higher than the suspect group (499.0 ± 48.1) and the other degrees of keratoconus (p < 0.001). Conclusions: Disease progression can significantly affect vision; therefore, early screening enables timely treatment (CXL). The evolution of this technique has contributed to preventing and slowing disease progression. Full article

Purpose: The purpose of this study is to evaluate changes in corneal thickness and anterior and posterior corneal curvature after one year of scleral lens wear in keratoconus eyes and to determine their impact on visual performance. Methods: Sixty-five keratoconus subjects were divided into two groups: with intrastromal corneal ring segments (KC-ICRS) and without ICRS (KC). All participants wore 16.5 mm scleral lenses for 8 h daily over 1 year. Measurements included corneal thickness, anterior and posterior curvature, and high-contrast visual acuity assessed before and after lens wear. Results: Corneal thicknesses increased significantly in the superior region of the KC-ICRS group. In curvature analysis, the KC group showed inferior steepening and superior flattening, while the KC-ICRS group exhibited central and superior-nasal anterior flattening. Posterior curvature changes included central flattening and peripheral steepening. Visual acuity remained stable across all visits and groups. Conclusions: Long-term scleral lens wear induced measurable morphological changes, including increased superior corneal thickness and region-specific curvature alterations, which varied by ICRS presence. These changes did not compromise visual acuity, supporting scleral lenses as a safe and effective option for sustained vision correction in keratoconus. The findings highlight the importance of personalized fitting and monitoring strategies in clinical practice. Full article

Objectives: The aim of this study was to evaluate changes in corneal topography, wavefront aberrations, and densitometry after superficial keratectomy (SK) for Salzmann nodular degeneration (SND). Methods: This was an observational retrospective study. Pre- and post-operative data, including best spectacle-corrected visual acuity (BCVA), refraction, and Pentacam^® topography scans, were analysed. Changes in keratometry (K), wavefront aberrations, and corneal optical densitometry (COD) were evaluated. Results: A total of 21 eyes of 17 patients who underwent SK for SND were included. At an average follow-up of 6.3 ± 4.4 months, there was a significant reduction in RMS (root mean square) values for total wavefront aberrations after surgery (mean reduction: −3.89 ± 4.08 μm, p = 0.001), lower-order aberrations (mean reduction: −3.47 ± 3.52 μm, p = 0.001), and higher-order aberrations (mean: −0.42 ± 0.58 μm, p < 0.001). There was a significant improvement in BCVA (mean change: 0.27 ± 0.31 logMAR, p < 0.001) and spherical equivalent (mean change: −2.09 ± 2.73 D, p = 0.002), and a reduction in refractive cylinder (mean reduction: −0.85 ± 1.14 D, p = 0.008). There was a significant reduction in corneal astigmatism (mean reduction 1.04 ± 2.88 D; p = 0.041), and an increase in flat keratometry (mean change 1.46 ± 3.10 D; p = 0.029). Lastly, there was a significant decrease in total COD values in all zones except for the central 2 mm (p < 0.05) and in the overall total 12 mm cornea (p = 0.035). Conclusions: SK for SND resulted in better visual acuity and potentially improved quality as suggested by the reduction in corneal aberrations and improvement in corneal regularity and transparency. Full article

Background and Objectives: Keratoconus is a progressive corneal ectatic disorder and a leading cause of corneal transplantation in developed countries. Early detection is critical for initiating timely interventions such as corneal cross-linking, which can halt disease progression and preserve long-term visual function. This review aims to synthesize current diagnostic approaches for early keratoconus detection and assess their clinical impact on visual outcomes. Materials and Methods: A comprehensive literature search was conducted across PubMed/MEDLINE, Web of Science, Google Scholar, Scopus and the Cochrane Library through September 2025. Search terms included “early keratoconus,” “subclinical keratoconus,” “forme fruste keratoconus,” “keratoconus detection,” “corneal topography,” “corneal tomography,” “anterior segment optical coherence tomography (AS-OCT),” “corneal biomechanics,” “artificial intelligence,” “genetic risk, “environmental factors”, and “machine learning.” Two independent reviewers analyzed the data. Studies were included if they investigated diagnostic modalities for early-stage keratoconus and discussed their relevance to visual outcomes. Results: One hundred and seven studies were included in the final review. Four diagnostic modalities demonstrated consistent clinical value: 1. corneal topography for assessing anterior surface irregularities; 2. corneal tomography, currently regarded as the gold standard due to its ability to detect early posterior elevation and pachymetric changes; 3. AS-OCT for epithelial and stromal profiling; and 4. biomechanical assessments, which evaluate corneal tissue stability prior to structural alterations. Artificial intelligence, when integrated with imaging data, enhances diagnostic sensitivity and standardizes interpretation across clinical settings. Conclusions: Early keratoconus detection is crucial for preserving vision; and integrating multimodal, AI-supported diagnostics into routine care—especially for high-risk groups—enhances accuracy, improves outcomes, and reduces progression rates of disease. Full article

Corneal fibroblasts adhere to the extracellular matrix via integrin-containing focal adhesions (FAs). Although topographical cues are known to influence FA patterning in corneal fibroblasts, it is unclear how ECM composition, biophysical cues, and specific integrins modulate FA patterning in corneal fibroblasts. In this study, we cultured a human corneal fibroblast cell line (HTKs) on different ECM proteins and micropatterns of aligned collagen fibrils to determine the effects of ECM topography and composition on focal adhesion subcellular patterning. Using confocal imaging, we observed and quantified changes in FA and integrin patterning based on the underlying ECM type. More specifically, the presence of fibrillar topography as compared to monomeric collagen resulted in diminished FA number, area, and length. Using specific integrin blocking antibodies, we also demonstrate that HTKs use different integrin subunits to adhere to specific ECM coatings. For example, β₁ integrins are important in adhesion formation when corneal fibroblasts adhere to collagen, while α₅ integrin is important for the HTKs to adhere to fibronectin. Blocking of α₅ integrin did not completely inhibit cell spreading and FA patterning when cells adhered to fibronectin. These results suggest that there might be other fibronectin receptors that HTKs use in the absence of α₅ integrin. These results lay the foundation to understand the role of different integrin subunits in FA patterning. Through further experimentation using our developed platform, we envision that a better understanding of the integrins and their associated signaling could have implications for advanced in vitro and in vivo applications in cornea biology. Full article