Cornea最新文献

Purpose: This review provides an overview of acute corneal hydrops (ACHs), focusing on their risk factors, epidemiology, pathogenesis, imaging techniques, and treatment options.

Methods: This narrative review was based on a literature search conducted in PubMed and Google Scholar, covering publications from 1980 to 2025. No restrictions were applied regarding language or study type. The identified studies were assessed for their relevance and clinical applicability to the diagnosis, management, and outcomes of ACHs.

Results: ACHs are linked with corneal conditions like keratoconus (2.6%-7.5%), pellucid marginal degeneration (6%-11.5%), and keratoglobus (11%). It arises from structural changes in Bowman layer and the anterior stroma, triggered by factors such as trauma and increased intraocular pressure, leading to rupture of Descemet membrane. Risk factors include chronic allergic eye diseases (eg, vernal and atopic keratoconjunctivitis), eye rubbing, developmental conditions (eg, Down syndrome), early age, steeper keratometry, and reduced visual acuity at presentation. Imaging techniques such as ultrasound biomicroscopy, anterior segment optical coherence tomography, and in vivo confocal microscopy aid in characterizing CHs, monitoring recovery, and detecting complications. Treatments aim to reduce discomfort, promote healing, prevent complications, and support future visual rehabilitation.

Conclusions: ACH develops in several corneal disorders, with risk factors overlapping those of keratoconus. Advances in imaging have improved the understanding of corneal changes, aiding in treatment and follow-up strategies. Despite various treatment options, no consensus exists on the best approach, underscoring the need for further studies to refine management and improve patient outcomes.

Purpose: Xeroderma Pigmentosum (XP) is a rare autosomal recessive disorder caused by defective nucleotide excision repair. Although dermatological features are well characterized, data on ocular manifestations and associated genotypes in Indian populations remain limited. This study aimed to delineate the ocular phenotype and underlying genetic variants in Indian patients with XP and compare them with global data.

Methods: Retrospective review of 23 patients with genetically confirmed XP was conducted. Variant pathogenicity was assessed using in silico tools. Logistic regression analysis and Generalized Estimating Equations model with a logit link function was used to evaluate any potential associations between clinical genetic parameters with the occurrence of ocular surface neoplasia (OSN).

Results: The cohort (median age: 24 years; male: female = 15:8) had a high consanguinity rate (69.6%). All patients reported of photophobia and visual impairment. Ocular surface dryness was also a notable complaint in 17%. Frequent ocular findings included conjunctival abnormalities (97%), corneal involvement (80%), and eyelid changes (70%). OSN or lid/adnexal tumors together were observed in 37% of eyes. Whole exome sequencing identified 18 pathogenic/likely pathogenic variants-15 in XP-C and 3 in DDB2 (XP-E), including 12 novel variants. There was a statistically significant increased risk of OSN in XP-E subtype compared with XP-C subtype.

Conclusions: XP-C was the predominant subtype, followed by XP-E in patients with XP with ocular involvement. XP-E subtype has been reported for the first time in Indian data in this study. Most variants were frameshift or stop gain. The patients with XP-E subtype may be more at risk of OSN development. These findings underscore the importance of routine ocular surveillance and genetic testing in XP.

Purpose: To present the clinical, topographic, and densitometry outcomes of patients with corneal fibrosis treated with topical losartan.

Methods: In this case series, patients with corneal scars treated with topical losartan 0.8 mg/mL 4 times a day for 6 months were included. Age, sex, cause of corneal opacity, months with corneal opacity, and previous topical treatment were recorded. Patients were examined at baseline and 1, 3, and 6 months after starting treatment. At each visit, uncorrected and best-corrected visual acuity, subjective refraction, intraocular pressure, slit-lamp examination, corneal tomography, and densitometry were performed. Patients were asked about drop comfort and possible side effects on a 0 to 10 self-reported scale.

Results: Eight eyes of 7 patients (4 males, 3 females, mean age 45.1 ± 12.0 years) were included. Best-corrected visual acuity logMAR was 0.28 ± 0.17 pretreatment and 0.17 ± 0.11 after 6 months of topical losartan ( P = 0.358). The visual acuity of 5 eyes improved, 1 eye remained unchanged, and the vision of 2 eyes declined. No changes in topographic and densitometry parameters were noted within the cohort analyzed as a group (all P > 0.05). No systemic side effects were reported, and tolerance was from very good to excellent (all 2/10 or better).

Conclusions: No significant improvements in visual acuity and densitometry values were noted with topical losartan in this series analyzed as a group. Further research to assess the full scope of clinical applications in corneal fibrosis is needed, particularly randomized clinical trials to address the effect of time and unequivocally prove its beneficial effects.

Purpose: A detailed study of the physicochemical properties of SMILE-derived lenticules and evaluation of their drug delivery after loading with silver nanoparticles (AgNPs).

Methods: The lenticules were decellularized and modified with crosslinking concentrations of 0.01 (0.01E/L), 0.05 (0.05E/L), and 0.25 (0.25E/L) mmol N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) per mg lenticule at 5:1 carbodiimide/N-hydroxysuccinimide (EDC/NHS) ratios. The degree of swelling, light transmittance, biomechanical properties, and stability of the non-crosslinked decellularized lenticules (DLs), 0.01E/L, 0.05E/L, and 0.25E/L were measured and characterized using Fourier transform infrared spectroscopy and transmission electron microscopy with non-crosslinked non-decellularized lenticules as controls. DLs, 0.01E/L, 0.05E/L, and 0.25E/L were soaked in AgNPs for 24 hours, and the concentration of the drug released was measured.

Results: There was no significant difference in the degree of swelling between the groups ( P > 0.05). The light transmittance of the lenticules did not change after decellularization and crosslinking and decreased after loading with AgNPs. Non-decellularized lenticules biodegraded within 108 to 120 hours, and the other groups biodegraded within 96 to 108 hours in vitro. The 0.01E/L had the highest tensile strength. The absorption peak intensity ratio of the amide I band and the amide II band decreased, and the arrangement of collagen fibers was more compact in crosslinked decellularized lenticules. The 0.01E/L had the highest cumulative drug release (3.4 ± 0.91 μg).

Conclusions: Crosslinking decellularization improved the biomechanical properties and resistance to water absorption of lenticules, increased covalent bonds between collagen fibers, and improved drug delivery. Crosslinked decellularized lenticules can be used as a new corneal patch material and drug delivery carrier for drug AgNPs.

Purpose: The corneal epithelium is endowed with a rare population of stem cells that reside within the limbus, a circumferential transition zone that partitions the cornea from the conjunctiva. These cells are thus referred to as limbal epithelial stem cells. Despite the surge in investigations using single-cell RNA sequencing (scRNA-seq) of the ocular surface, a unifying marker(s) that distinguishes these cells from their progeny is yet to be identified.

Methods: We used a keratin (K)-14-driven lineage-tracing system and SmartSeq-2 single-cell transcriptomics in 5- to 60-week-old mice to interrogate the identity of limbal epithelia. These results were then validated using flow cytometry, immunofluorescence, and a central corneal injury model.

Results: Four cell clusters were identified, derived from both Confetti + and Confetti - cells (clusters 0-3), with cluster 3 designated as harboring progenitor cells. We focused on one gene of interest in cluster 3, growth arrest-specific gene 1 ( Gas1 ), which codes for a cell-surface protein. PCR, flow cytometry, and immunofluorescence revealed that this gene is expressed in a rare population of limbal epithelial cells. Gas1 was also coexpressed with K14 in both young and old mice and upregulated after a mild mechanical debridement injury to the central cornea.

Conclusions: The cell-surface expression of this protein can be used to identify, extract, and enrich progenitor cells for downstream molecular investigations and for generating better-quality cell-based grafts to treat severe corneal disease.

Purpose: To describe the clinical features and management of ocular choristomas in mosaic RASopathy patients.

Methods: We performed a retrospective single-center case review of all mosaic RASopathy patients. We evaluated for the presence of corneal and epibulbar choristomas and conducted a comprehensive analysis of the imaging, including operative microscope images, slitlamp images, and optical coherence tomography images. In doing so, we provide a precise description for these types of choristomas.

Results: Nine patients with mosaic RASopathies, 7 men and 2 women (3 with clinical diagnoses of Linear Sebaceous Nevus Syndrome, 5 with Oculoectodermal Syndrome, and 1 with Encephalocraniocutaneous Lipomatosis), were evaluated. Fourteen eyes with ocular choristomas were identified among the 9 patients-bilaterally in 5 and unilaterally in 4. Molecular confirmation was available in 6 cases, and pathogenic variants in the KRAS gene were identified in all 6. None of the choristomas presented as discrete raised lesions at the limbus alone; they were all relatively flat, very vascularized, and in 4 of the 14 eyes, there was involvement of the visual axis, with 6 having extension with vascularization onto the cornea. All of them extended into the conjunctiva and into the sclera posteriorly.

Conclusions: Ocular choristomas with conjunctival and scleral extension, often with concomitant corneal vessels, should alert the clinician to the possibility of a mosaic RASopathy. Management can be complicated and includes measures such as optical iridectomy, anti-VEGF injections, and refractive correction with occlusion therapy, and corneal transplantation may also be considered.

Purpose: To report a case of Epstein-Barr virus (EBV) corneal endotheliitis and uveitis in a patient diagnosed with extranodal natural killer/T-cell lymphoma (ENKTL).

Methods: This is a case report performed at a tertiary care center in the Republic of Korea.

Results: A 64-year-old man presented with decreased vision in his right eye that had persisted for 4 days. Best-corrected visual acuity was finger counting at 50 cm in the right eye and 0.8 in the left eye. Intraocular pressure was within the normal range in both eyes. Slit-lamp examination revealed scattered keratic precipitations and diffuse corneal edema in the right eye. Because of the severe edema, anterior chamber (AC) details were obscured. In the left eye, +2 inflammatory cells were observed in the AC and +1 cells in the vitreous. A multiplex polymerase chain reaction test using aqueous humor samples from each eye yielded positive results for EBV but negative results for other herpes viruses. One week after initiating treatment with a topical acyclovir ointment, topical steroids, and oral acyclovir, corneal edema and AC inflammation improved. Subsequently, the patient was diagnosed with nasal ENKTL and underwent 3 chemotherapy cycles in the hematology-oncology department. Five months after commencing topical and oral antiviral therapies, best-corrected visual acuities improved to 0.5 in the right eye and 1.0 in the left eye.

Conclusions: EBV infection can cause severe corneal edema and uveitis. In patients with ENKTL, EBV should be considered a possible etiology of ocular involvement, and timely ophthalmic management may contribute to better visual outcomes.

Purpose: The objective of this study was to compare the clinical outcomes of intrastromal keratoplasty using biosynthetic corneas with human donor corneas in cases of advanced keratoconus.

Methods: A prospective nonblinded randomized controlled study was conducted at a tertiary eye center in India. Treatment-naïve patients with advanced keratoconus aged 18 years or older were included. Twenty eyes were randomized into 2 groups-group 1 (human donor corneal lenticule, n = 10) and group 2 (biosynthetic corneal lenticule, n = 10). Efficacy analyses included an increase in the thinnest pachymetry and a decrease in the maximum keratometry (Kmax). Safety analyses included any adverse events in the postoperative period.

Results: At 6 months postoperatively, the rise in the thinnest pachymetry in group 1 was 346.8 ± 40.82 to 486.7 ± 15.7 μm ( P < 0.001) and in group 2 was 366.2 ± 31.3 to 548.3 ± 59.1 μm ( P < 0.001). The biosynthetic group exhibited a significant increase in the thinnest pachymetry ( P = 0.005). However, both groups showed a similar decrease in Kmax (71.06 ± 7.95 to 63.3 ± 3.74 D in group 1 and 69.13 ± 8.54 to 61.5 ± 6.2 D in group 2; P = 0.44). No adverse events were seen at 6 months of follow-up.

Conclusion: Femtosecond-assisted intrastromal implantation of biosynthetic corneas is a safe and effective alternative to human donor corneas in cases of advanced keratoconus.