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Corneal Epithelial Alterations Associated With Cyclin-Dependent Kinase 4/6 Inhibitor Therapy in Hormone Receptor-Positive Breast Cancer.

IMPORTANCE: Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors are standard therapy for hormone receptor-positive (HR+), HER2-negative breast cancer. By blocking the G1/S cell-cycle transition, these agents may impair renewal of the corneal epithelium. No controlled study has systematically evaluated corneal epithelial changes in patients receiving CDK4/6 inhibitors. OBJECTIVE: To determine whether CDK4/6 inhibitor-based therapy is associated with cornealepithelial alterations independent of aromatase inhibitor exposure and tear film dysfunction. DESIGN, SETTING, AND PARTICIPANTS: Retrospective comparative cross-sectional study at a tertiary ophthalmology center. A total of 132 women were enrolled: 45 receiving a CDK4/6 inhibitor plus an aromatase inhibitor (CDKAI group), 44 receiving aromatase inhibitor monotherapy (AI group), and 43 age-matched postmenopausal controls without systemic oncologic therapy. EXPOSURES: CDK4/6 inhibitor (ribociclib, palbociclib, or abemaciclib) combined with an aromatase inhibitor; aromatase inhibitor alone; or no systemic oncologic therapy. MAIN OUTCOMES AND MEASURES: Prevalence and severity of punctate epitheliopathy and vortex keratopathy, assessed by a masked ophthalmologist. Secondary outcomes included Schirmer I test, tear film break-up time, and Ocular Surface Disease Index (OSDI). RESULTS: PE was present in 44.4% of eyes in the CDKAI group vs 4.7% in the AI group and 2.3% in controls (&#x3c7;&#xb2; = 34.31; P < .001). All moderate (13.3%) and severe/complicated (8.9%) PE cases occurred exclusively in the CDKAI group. Vortex keratopathy was observed in 13.3% of CDKAI patients and in none of the other groups (P = .025). Schirmer values, tear film break-up time, and OSDI scores did not differ among groups (all P > .05). Within the CDKAI group, PE was not associated with treatment duration (P = .963) or tear film parameters. CONCLUSIONS AND RELEVANCE: In this comparative study, CDK4/6 inhibitor-based therapy was associated with significantly higher prevalence and severity of PE and vortex keratopathy, independent of aromatase inhibitor exposure and in the absence of measurable tear film dysfunction. These findings suggest a direct cytostatic effect on the corneal epithelium. Symptom scores were low, although OSDI interpretation was limited by incomplete responses. Proactive corneal surface evaluation with fluorescein staining may be warranted during CDK4/6 inhibitor treatment.

Humans

Descemet Stripping Only in Fuchs Endothelial Corneal Dystrophy: Results of a Randomized Clinical Trial of Topical Ripasudil and Directions for Future Innovation.

PURPOSE: To review history of Descemet stripping only (DSO) in Fuchs endothelial corneal dystrophy, describe the results of a clinical trial of topical ripasudil after DSO (K-321-201 study), and discuss future directions. METHODS: A 1-year, phase 2, randomized, placebo-controlled multicenter clinical trial of two doses of K-321 (ripasudil) administered for 12 weeks after DSO surgery in Fuchs endothelial corneal dystrophy was performed. The primary endpoint, central corneal endothelial cell density (ECD) at 12 weeks after surgery, was determined by an independent reading center that was masked to study group assignment. Duration of corneal edema, need for medical or surgical rescue therapy, corneal thickness, and central ECD throughout the entire study period were also examined. Adverse events and exploratory endpoints were collected. RESULTS: Sixty-five subjects were enrolled (21 in the QID group, 22 in the BID, and in the placebo group). Over 95% of subjects completed the trial. The QID group had a higher central ECD 12 weeks after DSO than the placebo group (531 &#xb1; 312 cells/mm2 vs 228 &#xb1; 298 cells/mm2, P = .0065). Corneal edema cleared in 17/21 (81.0%) of the QID group at 12 weeks, compared with 2/22 (9.1%) of the placebo group (P < .0001). Rescue was required in 2/21 (9.5%) subjects in the QID group and 6/22 (27.3%) subjects in the placebo group (P = .0092). Adverse events were mild and did not lead to discontinuation of treatment. CONCLUSIONS: Topical K-321 given QID improves DSO outcomes, as demonstrated by a higher ECD, more rapid resolution of corneal edema, and reduced failure rate. The medication was well-tolerated.

Humans

Second-Generation ELZA-sub400 Protocol: Individualized High-Fluence Cross-Linking for Ultra-Thin Keratoconus Corneas.

PURPOSE: To evaluate the safety and efficacy of a second-generation individualized corneal cross-linking (CXL) protocol (ELZA-sub400) using high-fluence UV-A irradiation in ultrathin ectatic corneas. DESIGN: Retrospective, single-center, consecutive interventional case series. METHODS: Twenty-nine eyes of 24 patients with progressive keratoconus or post-LASIK ectasia and a post-soak intraoperative thinnest stromal thickness <400 &#xb5;m were included. After epithelial removal and riboflavin soaking, continuous UV-A irradiation (365 nm) at 3 or 9 mW/cm&#xb2; was delivered with total fluence titrated up to 10 J/cm&#xb2; based on intraoperative ultrasound pachymetry and a previously published nomogram targeting an uncross-linked stromal margin of approximately 70 &#xb5;m above the endothelium. Outcomes were assessed at baseline and up to 12 months using corrected distance visual acuity (CDVA) and corneal parameters measured using Scheimpflug tomography and anterior segment OCT (AS-OCT) with Placido-based topography. The main outcome measure was the proportion of eyes without progression at 12 months, defined as <1.0 D increase in maximum keratometry (Kmax). Secondary outcomes included changes in CDVA, refraction, Kmax, stromal thickness, demarcation line depth, densitometry, and safety parameters. RESULTS: At 12 months, 22/29 eyes (76%; 95% CI, 57.9%-87.8%) met the nonprogression criterion. Mean change in Kmax was -0.77 &#xb1; 5.10 D (95% CI, -2.71 to 1.17; P = .418). Mean demarcation line-to-anterior stroma distance was 205 &#xb1; 64 &#xb5;m (95% CI, 180.7-229.3), and demarcation line-to-endothelium distance was 64 &#xb5;m (IQR, 49-152). All demarcation lines remained within the stromal layer; 15/29 eyes (51.7%) had a demarcation line located &#x2264;70 &#xb5;m from the endothelium. Median CDVA changed from 0.10 to 0.32 logMAR (P = .142). Minimum stromal thickness showed a median change of -4.0 &#xb5;m (P = .309). No significant change was observed in densitometry, and no eye developed deep stromal haze or endothelial decompensation. CONCLUSIONS: Second-generation ELZA-sub400 CXL halted ectasia progression in 76% of ultrathin corneas at 12 months and was associated with an acceptable short-term safety profile, including stromal-confined demarcation line formation and no observed endothelial decompensation. The numerical decline in spectacle CDVA observed in this severely affected cohort did not reach statistical significance but is clinically important and warrants confirmation in larger prospective studies.

Humans

Posterior Segment Risk Factors for Penetrating Keratoplasty Failure.

PURPOSE: To analyze the relationship between intraoperative and postpenetrating keratoplasty (PK) posterior segment variables and PK graft survival. DESIGN: Retrospective clinical cohort study. SUBJECTS: Patients undergoing PK between May 1, 2007 and September 1, 2018 at a single tertiary center. METHODS: Chart review for PKs performed was conducted, and the first PK completed at the institution for each patient was included for analysis. Data collected included demographics, medical and ocular history, preoperative and intraoperative findings, and intraoperative and postoperative posterior segment factors (pars plana vitrectomy [PPV], endolaser, retinal detachment [RD], and vitreous hemorrhage [VH]). After univariable analysis, variables were selected for multivariable Cox regression analysis. MAIN OUTCOME MEASURE: Graft failure, defined as irreversible and visually significant corneal edema, haze, or scarring. RESULTS: Eight hundred and thirty-five eyes of 835 patients were included. Mean age was 57.1 &#xb1; 22.0 (range: 0-100) years, and mean time from PK to final follow-up or graft failure was 3.2 &#xb1; 2.9 (range: 0.01-16.1) years. Graft failure occurred in 35.0% of cases with a mean onset of 1.9 &#xb1; 2.0 (range: 0.04-11.4) years after PK. After multivariable analysis, 9 variables had significant associations with failure. Two posterior segment variables were significant: intraoperative VH at the time of PK (hazard ratio [HR] 6.6, 95% confidence interval [CI] 1.6-27.7, P = .010) and silicone oil (SO) tamponade after the PK (HR 3.2, 95% CI 1.4-7.4, P = .007). CONCLUSIONS: Graft failure is a serious complication of PK. VH at the time of the PK and SO tamponade after the PK were associated with graft failure. In complex eyes that are undergoing PK grafts and that may also require posterior segment interventions, these findings may guide patient counseling and discussion of graft prognosis.

Humans

Impact of Contact Lens Use on Clinical Profile and Outcomes of Fungal Keratitis: An 8-Year Retrospective Study.

PURPOSE: To compare clinical characteristics, microbiological profiles, treatment strategies, and outcomes between contact lens-associated (CL) and noncontact lens-associated (non-CL) fungal keratitis. DESIGN: Retrospective, comparative clinical cohort study. METHODS: A review of culture-proven fungal keratitis treated at a tertiary referral center between 2018 and 2025 was conducted. Cases were categorized as CL or non-CL-associated. Demographic, clinical, microbiological, treatment, and outcome data were analyzed and compared between groups. RESULTS: Thirty-seven eyes were included, comprising 16 CL and 21 non-CL cases. CL users presented earlier than non-CL patients (median 7 vs 14 days, P = .007) and had fewer associated ocular risk factors (31% vs 81%, P = .001). Baseline visual acuity and infiltrate size did not differ significantly between groups. Candida species were isolated in 21% cases, Fusarium in 16% and Aspergillus in 8%. Fusarium (19% vs 13%) and Candida (24% vs 19%) infections were slightly more frequent in non-CL cases. Overall, filamentous fungi were the predominant organism group. Topical voriconazole was the most frequently used antifungal agent (78%). All CL-associated cases resolved with medical therapy alone, with a median time to resolution of 38 days (IQR 22-58). In contrast, 76% of non-CL cases resolved medically (median 42 days, IQR 32-76), while 23% required therapeutic keratoplasty (P = .04). Final visual acuity was comparable between groups (logMAR 0.2 vs 0.5, P = .56). CONCLUSION: Contact lens-associated fungal keratitis is characterized by earlier presentation and fewer underlying ocular comorbidities, with favorable outcomes achieved through medical therapy alone. Despite similar microbiological profiles and treatment approaches, noncontact lens-associated fungal keratitis more frequently follows a complicated course requiring surgical intervention.

Humans

Parallel evolutionary trajectories rewire enteropathogenic Escherichia coli adhesion to restore host attachment.

Enteropathogenic Escherichia coli (EPEC) causes disease in children, presenting as chronic diarrhea that can impair physical and cognitive development. The attachment of typical EPEC (tEPEC) to the gut epithelium via bundle-forming pili (BFP) is a key factor in its virulence. Yet, infections by atypical EPEC (aEPEC), which lack BFP, have become increasingly common. To investigate how aEPEC recover host-attachment in the absence of BFP, we performed experimental evolution using a non-adherent E. coli, constructed to mimic the ancestor of aEPEC, and selected adherent progeny. Highly adherent variants evolved through phase-variable activation of type I fimbriae (T1F), followed by two alternative trajectories: bacterial filamentation, which increases T1F avidity, or point mutations in the T1F adhesin FimH that enhance ligand affinity. Extending our analysis to the genomes of 327 aEPEC strains isolated from infected patients revealed that similar FimH mutations are common. We further demonstrated experimentally that these naturally occurring variants often increase epithelial-attachment. Our findings implicate T1F in aEPEC pathogenesis and suggest it may be clinically relevant for anti-adhesion therapy. More broadly, these results indicate that impaired host-attachment can be rapidly compensated by upregulating and optimizing an alternative adhesin, and that combining experimental evolution with comparative genomics can reveal evolutionary trajectories occurring in nature.

Bacterial Adhesion

Xerophthalmia and ocular manifestations of vitamin A deficiency in children in high-income countries: A systematic review.

Xerophthalmia is a vision-threatening eye condition caused by vitamin A deficiency (VAD). Cases of xerophthalmia in high-income countries (HICs) are vulnerable to misdiagnosis, causing delays in treatment and adverse visual outcomes. We define the features, causes and complications of VAD and xerophthalmia in children of HICs. Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines (CRD42024492023). We performed a search for eligible articles on Scopus, Web of Science, Cochrane, PubMed and Medline. Cases reporting on children under 18 years of age residing in HICs with ocular features of VAD were eligible for inclusion. The search yielded 2474 results; 43 case reports and case series met the inclusion criteria consisting of a total of 61 cases (mean age 9.9&#x202f;&#xb1;&#x202f;4.2 years, range 3-17 years). Xerophthalmia was graded according to the most advanced finding for each case: 21.3% had night blindness only; 29.5% had conjunctival xerosis or Bitot spots; 29.5% had corneal xerosis, ulceration or scarring; 1.6% had xerophthalmia fundus only; and 18.0% had ocular manifestations associated with VAD that are not encompassed under the WHO classification. These features included swollen optic discs, optic neuropathy, or ocular dryness. Restrictive dietary practises were the most common mechanism of deficiency (75%), and autism was the most common underlying condition (49%). This shows that VAD remains a cause of severe visual impairment in HICs, especially when associated with delays in diagnosis and treatment. Further research is required to establish the prevalence of xerophthalmia in HICs.

Humans

Axial Length Adjustment and AL/R Ratio Optimization of IOL Power Calculation in Extremely Long Eyes.

PURPOSE: To evaluate the accuracy of modern intraocular lens (IOL) power calculation formulas and axial length (AL) adjustment methods in eyes with AL &#x2265; 30.0 mm. DESIGN: Retrospective consecutive cross-sectional study. PARTICIPANTS AND CONTROLS: A total of 308 eyes (308 patients) with AL &#x2265; 30.00 mm were included. METHODS: Accuracy of modern online formulas, alone or with established AL adjustments methods, was analyzed. Subgroup analyses were performed based on AL, keratometry (K), anterior chamber depth (ACD), lens thickness (LT), and AL-to-corneal radius (AL/R) ratio. MAIN OUTCOME MEASURES: Predictive accuracy was evaluated using the formula performance index (FPI), root mean square absolute prediction error (RMSAE), standard deviation (SD) of prediction error (PE), and percentage of eyes within &#xb1;0.25 and &#xb1;0.50 diopters (D). RESULTS: Overall, Holladay 1 combined with the nonlinear polynomial Wang-Koch axial length adjustment (H1-PWK) demonstrated the best overall performance, achieving the lowest SD (0.40), RMSAE (0.40), and highest FPI (0.494). A tendency toward hyperopic error was observed in eyes with AL &#x2265; 32.0 mm, K &#x2265; 46.0 D. The AL/R ratio showed a significant positive correlation with PE in the Ladas Super formula, Barrett Universal II, EVO, PEARL-DGS, and Hoffer QST formulas. Spline-based regression analysis indicated that the transition point of AL/R from myopic to hyperopic PE varied across different formulas. CONCLUSIONS: H1-PWK provides robust refractive accuracy in extremely long eyes. The AL/R ratio may provide a useful composite biometric stratification parameter compared to AL alone.

Humans

Association Between 24-Hour Blood Pressure and Rates of Retinal Nerve Fiber Layer Progression in Glaucoma: The Vascular Imaging in Glaucoma Study.

PURPOSE: Low systemic blood pressure (BP) has been implicated as a risk factor for glaucoma progression. The purpose of this study was to investigate the association between 24-hour BP and rates of retinal nerve fiber layer (RNFL) loss in eyes with primary open-angle glaucoma. DESIGN: Prospective cohort study. PARTICIPANTS: Seventy-nine eyes from 42 subjects with glaucoma (mean age, 68.5 &#xb1; 7.6 years) enrolled in the Vascular Imaging in Glaucoma Study at the Bascom Palmer Eye Institute. METHODS: Participants underwent 24-hour ambulatory BP monitoring at baseline. Follow-up evaluations were conducted at 4-month intervals and included ophthalmic examination, BP measurement, and peripapillary RNFL thickness measurement with spectral-domain optical coherence tomography. The association between BP and RNFL loss over time was assessed using linear mixed-effects models adjusted for age, sex, race, baseline RNFL thickness, central corneal thickness, and intraocular pressure. MAIN OUTCOME MEASURES: The effect of baseline 24-hour mean arterial pressure (MAP), systolic BP (SBP), and diastolic BP (DBP) on the rate of average RNFL loss over time. RESULTS: Eyes underwent an average of 13 &#xb1; 3 optical coherence tomography exams over 43 &#xb1; 10 months of follow-up. The mean rate of RNFL loss was -0.34 &#xb1; 0.64 &#xb5;m/y (median: -0.32; interquartile range: -0.66 to -0.04 &#xb5;m/y). After adjusting for confounding factors, every 10 mm Hg lower in 24-hour minimum MAP, SBP, and DBP was associated with -0.542 &#xb5;m/y (P < .001), -0.360 &#xb5;m/y (P = .003), and -0.458 &#xb5;m/y (P = .008) faster RNFL loss, respectively. Eyes in the lowest quartile of average 24-hour MAP (81-90 mm Hg) and minimum 24-hour DBP (35-47 mm Hg) experienced significantly faster progression compared to those in the highest quartile, with differences of -0.68 &#xb5;m/y (P = .017) and -0.63 &#xb5;m/y (P = .030), respectively. CONCLUSIONS: Lower systemic BP, especially minimum MAP, SBP, and DBP measured by 24-hour ambulatory BP monitoring, is associated with faster rates of RNFL loss in primary open-angle glaucoma eyes. 24-hour BP monitoring may help predict glaucoma patients at greater risk of progression.

Humans