Kuragel: A biomimetic hydrogel scaffold designed to promote corneal regeneration.

Cornea-related injuries are the most common cause of blindness worldwide. Transplantation remains the primary approach for addressing corneal blindness, though the demand for donor corneas outmatches the supply by millions. Tissue adhesives employed to seal corneal wounds have shown inefficient healing and incomplete vision restoration. We have developed a biodegradable hydrogel - Kuragel, with the ability to promote corneal regeneration. Functionalized gelatin and hyaluronic acid form photo-crosslinkable hydrogel with transparency and compressive modulus similar to healthy human cornea. Kuragel composition was tuned to achieve sufficient adhesive strength for sutureless integration to host tissue, with minimal swelling post-administration. Studies in the New Zealand rabbit mechanical injury model affecting corneal epithelium and stroma demonstrate that Kuragel efficiently promotes re-epithelialization within 1 month of administration, while stroma and sub-basal nerve plexus regenerate within 3 months. We propose Kuragel as a regenerative treatment for patients suffering from corneal defects including thinning, by restoration of transparency and thickness.

Chemical (Alkali) Burn-Induced Neurotrophic Keratitis Model in New Zealand Rabbit Investigated Using Medical Clinical Readouts and In Vivo Confocal Microscopy (IVCM).

PURPOSE: Chemical eye injury is an acute emergency that can result in vision loss. Neurotrophic keratitis (NK) is the most common long-term manifestation of chemical injury. NK due to alkali burn affects ocular surface health and is one of its most common causes. Here, we established a rabbit model of corneal alkali burns to evaluate the severity of NK-associated changes. MATERIAL METHODS: Alkali burns were induced in NZ rabbits by treating the cornea with (i) a 5 mm circular filter paper soaked in 0.75 N NaOH for 10 s (Mild NK) and (ii) trephination using a guarded trephine (5 mm diameter and 150-micron depth), followed by alkali burn, with a 5 mm circular filter paper soaked in 0.75 N NaOH for 10 s (a severe form of NK). Immediately after, the cornea was rinsed with 10 mL of normal saline to remove traces of NaOH. Clinical features were evaluated on Day 0, Day 1, Day 7, Day 15, and Day 21 post-alkali burn using a slit lamp, Pentacam, and anterior segment optical coherence tomography (AS-OCT). NK-like changes in epithelium, sub-basal nerve plexus, and stroma were observed using in vivo confocal microscopy (IVCM), and corneal sensation were measured using an aesthesiometer post alkali injury. After 21 days, pro-inflammatory cytokines were evaluated for inflammation through ELISA. RESULTS: Trephination followed by alkali burn resulted in the loss of epithelial layers (manifested using fluorescein stain), extensive edema, and increased corneal thickness (550 µm compared to 380 µm thickness of control) evaluated through AS-OCT and increased opacity score in alkali-treated rabbit (80 compared to 16 controls). IVCM images showed complete loss of nerve fibers, which failed to regenerate over 30 days, and loss of corneal sensation-conditions associated with NK. Cytokines evaluation of IL6, VEGF, and MMP9 indicated an increased angiogenic and pro-inflammatory milieu compared to the milder form of NK and the control. DISCUSSION: Using clinical parameters, we demonstrated that the alkali-treated rabbit model depicts features of NK. Using IVCM in the NaOH burn animal model, we demonstrated a complete loss of nerve fibers with poor self-healing capability associated with sub-basal nerve degeneration and compromised corneal sensation. This pre-clinical rabbit model has implications for future pre-clinical research in neurotrophic keratitis.

Dealing With Pericylindrical Melts in Keratoprosthesis: Tenon Patch Graft to the Rescue.

PURPOSE: The aim of this study was to describe the outcomes of autologous Tenon patch graft in the management of Auro keratoprosthesis-related pericylindrical corneal melt. METHODS: We report 3 cases of sterile pericylindrical corneal melt in patients with Auro keratoprosthesis implantation after a mean duration of 5 years (1.5-8 years). Case 1 was a patient with severe graft-versus-host disease. Cases 2 and 3 were cases of chemical injury.All these cases of sterile pericylindrical corneal melt (4-6 mm) underwent autologous Tenon patch graft. The technique included freshening of the edges around the melt, followed by measuring the size of the defect. A Tenon graft harvested from the patient's own eye was used to seal the defect and act as a scaffold. The Tenon patch graft was spread over the melt and held in place by the application of fibrin glue and/or interrupted 10-0 nylon sutures. A bandage contact lens was then placed on the eye. RESULTS: Tenon patch graft was well taken in all patients. The mean duration of epithelial healing was 1 month. Globe integrity was well maintained with no postoperative complications at a mean follow-up duration of 12 months (6-18 months). CONCLUSIONS: Corneal melt is one of the most dreaded complications of KPro because its occurrence could threaten visual prognosis and globe integrity. Autologous Tenon patch is a simple yet innovative and effective option to steer such eyes away from potentially dreadful complications.

Krupple-like factor 4 (KLF4) methylation signature in host cell in active viral keratitis with epithelial manifestation.

HSV1 presents as epithelial or stromal keratitis or keratouveitis and can lead to sight-threatening complications. KLF4, a critical transcription factor, and regulator of cell growth and differentiation, is essential in corneal epithelium stratification and homeostasis. Here, we want to understand the epigenetic modification specifically the methylation status of KLF4 in epithelium samples of HSV1 keratitis patients. After obtaining consent, epithelial scrapes were collected from 7 patients with clinically diagnosed HSV1 keratitis and 7 control samples (patients undergoing photorefractive keratectomy). Genomic DNA was isolated from the collected samples using the Qiagen DNeasy Kit. Subsequently, bisulfite modification was performed. The bisulphite-modified DNA was then subjected to PCR amplification using specific primers designed to target the KLF4, ACTB gene region, allowing for the amplification of methylated and unmethylated DNA sequences. The amplified DNA products were separated and visualized on a 3% agarose gel. KLF4 hypermethylation was found in 6 out of 7 (85.71%) eyes with viral keratitis, while 1 eye showed hypomethylation compared to PRK samples. Out of these 6, there were 2 each of epithelial dendritic keratitis, epithelial geographical keratitis, and neurotrophic keratitis. The patient with hypomethylated KLF4 had a recurrent case of HSV1 keratitis with multiple dendrites and associated vesicular lesions of the lip along with a history of fever. KLF4 hypermethylation in most viral keratitis cases indicated the under functioning of KLF4 and could indicate a potential association between KLF4 hypermethylation and the development or progression of HSV1 keratitis.

Visual outcome and postoperative complications of cataract surgery in patients with ocular surface disorders.

PURPOSE: To determine the visual outcome and postoperative complications of cataract surgery in patients with ocular surface disorders (OSDs). SETTING: Tertiary eyecare center in North India. DESIGN: Retrospective observational study. METHODS: Patients with various OSDs with stabilized ocular surfaces who underwent cataract surgery during this period and had a minimum postoperative follow-up of 6 weeks were included. The primary outcome measures were postoperative corrected distance visual acuity (CDVA) at 6 weeks, best CDVA achieved, and postoperative complications. RESULTS: The study included 20 men and 24 women. A total of 55 eyes were evaluated: Stevens-Johnson syndrome (SJS) 35 eyes, ocular cicatricial pemphigoid (OCP) 4 eyes, 8 eyes with dry eye disease (DED), 6 eyes with chemical injury and 2 eyes with vernal keratoconjunctivitis (VKC). The mean duration of OSD was 33.9 ± 52.17 months. The median preoperative CDVA was 2.0 (interquartile range [IQR], 1.45 to 2.0). The median CDVA ever achieved was 0.50 (IQR, 0.18 to 1.45) at 2 months and the median CDVA at 6 weeks was 0.6 (IQR, 0.3 to 1.5). Maximum improvement in CDVA was noted in patients with DED and SJS and the least in OCP. Phacoemulsification was performed in 47.27% eyes with intraoperative complications noted in 9% eyes. Postoperative surface complications occurred in 12 (21.82%) eyes. Other postoperative complications occurred in 9 (16%) eyes. CONCLUSIONS: Cataract surgery outcome can be visually rewarding in patients with OSDs provided ocular surface integrity is adequately maintained preoperatively and postoperatively.

In vitro Assay to Examine the Function of Tears on Corneal Epithelial Cells.

Tears contain numerous secreted factors, enzymes, and proteins that help in maintaining the homeostatic condition of the eye and also protect it from the external environment. However, alterations to these enzymes and/or proteins during pathologies such as mechanical injury and viral or fungal infections can disrupt the normal ocular homeostasis, further contributing to disease development. Several tear film components have a significant role in curbing disease progression and promoting corneal regeneration. Additionally, several factors related to disease progression are secreted into the tear film, thereby serving as a valuable reservoir of biomarkers. Tears are readily available and can be collected via non-invasive techniques or simply from contact lenses. Tears can thus serve as a valuable and easy source for studying disease-specific biomarkers. Significant advancements have been made in recent years in the field of tear film proteomics, lipidomics, and transcriptomics to allow a better understanding of how tears can be utilized to gain insight into the etiology of diseases. These advancements have enabled us to study the pathophysiology of various disease states using tear samples. However, the mechanisms by which tears help to maintain corneal homeostasis and how they are able to form the first line of defense against pathogens remain poorly understood and warrant detailed in vitro studies. Herein, we have developed an in vitro assay to characterize the functional importance of patient isolated tears and their components on corneal epithelial cells. This novel approach closely mimics real physiological conditions and could help the researchers gain insight into the underlying mechanisms of ocular pathologies and develop new treatments. Key features • This method provides a new technique for analyzing the effect of tear components on human corneal epithelial cells. • The components of the tears that are altered in response to diseases can be used as a biomarker for detecting ocular complications. • This procedure can be further employed as an in vitro model for assessing the efficacy of drugs and discover potential therapeutic interventions.

Bridging the gap: The promise of corneal bioengineering and regeneration.

In recent years, significant advances in tissue engineering and regenerative medicine have led to innovative approaches in addressing the various challenges associated with corneal transplants using bioengineered corneas. This mini-review aims to introduce the general ophthalmologist to the concept and technique of bioengineered cornea and provide an overview of the developments so far and an insight into the future direction. By summarizing the latest research and current limitations, we aim to highlight their potential for the future in ultimately contributing to vision restoration.

P25-A123†Indo - German GIZ collaboration - impact and way forward in global eye banking.

PURPOSE: Geographical imbalance in cornea supply is a key feature of global eye banking. Most countries of South Asia particularly India suffer from donor cornea shortage which limits the number of keratoplasties, thereby aggravating the already high burden of removable blindness. The purpose of the project is to identify and cross-pollinate best practices from two leading eye banking institutions in India and Germany, and thereby improve service delivery of both systems. The project is supported by the GIZ Hospital Partnerships funding program on behalf of the Federal Ministry for Economic Cooperation and Development (BMZ) with a co-financing by the Else Kröner-Fresenius Foundation (EKFS). It started in 2021 and will last upto 2023. METHODS: A joint expert group from both organisations conducted a series of workshops to identify the areas of intervention and specific practices to be introduced at the Indian partner's region. The overall increase in cornea collections and transplants, documented systemic improvement measures and research output were defined as the key outcomes. RESULTS: Interim results are presented here. Two interventions identified were expansion of catchment area of cornea collection in India, and improved information management system to monitor the progress and efficiency of the collection centres. Under the former intervention, the hub-and-spoke model from the German partner was introduced to the most populous state of India through establishment of two new cornea collection centres (spokes) for Hospital based Cornea collections. In six months these centres have supplied 79 donor corneas leading to 63 transplants at the hub. Under the latter intervention, the specifications of a baseline data capture and operations management system which can be used in low resource settings are being developed. CONCLUSION: The initiative has shown how best practice from one geography can be adapted and successfully implemented in another geography , Furthermore, the public knowledge resources created in the project can be used by other eye banks to advance eye banking in their respective countries.

Management of cataract in dry eye disease: Preferred practice pattern guidelines.

Cataract surgery is one of the most commonly performed ophthalmic surgeries in the world. Dry eye disease (DED) is found to coexist in most patients with cataracts due to the overlapping age groups of both these conditions. Preoperative evaluation for DED is important to improve outcomes. A pre-existing DED affecting the tear film is likely to affect biometry. Moreover, special intraoperative considerations are needed in eyes with DED to reduce complications and improve postoperative outcomes. Dry eye disease (DED) is known to occur following an uneventful cataract surgery or a pre-existing DED is likely to worsen following cataract surgery as well. In these situations, despite a good visual outcome, patient dissatisfaction is common owing to the distressing DED symptoms. This review aims to summarize the preoperative, intraoperative, and postoperative considerations when performing cataract surgery in the presence of a coexisting DED.

Evaluation of dry eyes in children with vernal kerato-conjunctivitis using clinical tests and ocular surface analysis.

Purpose: To evaluate dry eyes in children with vernal kerato-conjunctivitis (VKC) and correlate it with symptoms, clinical findings, and ocular surface analysis (OSA) parameters. Methods: Children with clinically diagnosed VKC underwent complete ophthalmological examination, Schirmer's testing, modified ocular surface disease index (OSDI) scoring, Bonini grading, fluorescein tear-film break-up time (TBUT), VKC - Collaborative Longitudinal Evaluation of Keratoconus (CLEK) scoring, and OSA. Children with a TBUT of < 10 s were defined to have dry eyes. The above-mentioned parameters were compared between dry eye and non-dry eye VKC children. Results: The mean age of the 87 children included in the study was 9.1 ± 2.9 years. Dry eyes were seen in 60.9% [95% confidence interval (CI); 51% to 71%]. The mean TBUT was 13.4 ± 3.8 and 5.9 ± 1.9 s in non-dry and dry eye groups, respectively (P < 0.001). The mean value of Schirmer's test was 25.9 ± 9.8 and 20.8 ± 8.6 mm in the non-dry and dry eye groups, respectively (P = 0.01). The two groups did not differ in their OSDI scores, Bonini grading, and CLEK scores. The OSA parameter of non-invasive break-up time (NIBUT) was 8.3 ± 3.2 s in non-dry eye group and 6.4 ± 2.9 s in dry eye group, P = 0.008. The lower lid Meibomian gland (MG) loss was 7.4% in non-dry eye group and 12.2% in dry eye group, P = 0.028. Other OSA parameters did not differ significantly among the two groups. Conclusion: Dry eyes are seen in two-thirds of pediatric VKC. Evaluation of dry eyes should be incorporated in their clinical evaluation. Among OSA parameters, NIBUT and lower lid MG loss are associated with dry eyes in pediatric VKC patients.

Efficacy and safety of 0.05% micellar nano-particulate (MNP) cyclosporine ophthalmic emulsion in the treatment of moderate-to-severe keratoconjunctivitis sicca: a 12-week, multicenter, randomized, active-controlled trial.

BACKGROUND: Keratoconjunctivitis sicca or dry eye disease (DED) is a multifactorial disorder underpinned by a complex inflammatory cycle. Introduction of topical cyclosporine has been a significant advance in the management of DED. In recent years advancements in formulation technology have led to development of micellar nano-particulate (MNP) cyclosporine formulations that promise better penetration into ocular target tissues and potential for reduced ocular surface irritation. METHODS: We compared two dosing regimes of a proprietary MNP cyclosporine emulsion with the widely marketed topical cyclosporine formulation Restasis™ in a multicenter parallel-group randomised trial in patients with DED. Patients were randomised to one of 3 treatment groups with 90 patients eligible for the per protocol analysis: 30 in the higher dose test arm A; 32 in the lower dose test arm B; and 28 in the Restasis™ control arm C. All scored efficacy endpoints were tested for significance by comparing the mean change in scores from baseline in the test groups with that in the control group at 12 weeks, using the Student's t test. Wilcoxon's rank sum test was used to test individual symptom scores and clinician's global evaluation of treatment grades. RESULTS: Corneal fluorescein staining score, the primary efficacy endpoint, decreased by 6.8 ± 4.0, 5.7 ± 3.9, and 4.6 ± 3.6 points in the 3 groups respectively, indicating superior efficacy in test arm A in comparison to control arm C (p = 0.0026). Schirmer's tear test, conjunctival lissamine staining score, ocular surface disease index, and individual dry eye symptom scores also favoured higher dose MNP cyclosporine over Restasis™. The study failed to differentiate the treatment arms in terms of clinician's global evaluation of treatment, use of tear substitutes, best corrected visual acuity or safety and toleration. CONCLUSION: The results indicate that the dose of 1 drop of a 0.05% w/v ophthalmic emulsion of MNP cyclosporine administered topically twice daily yields better outcomes at 12 weeks than the lower dose tested in the study, and is more efficacious than an equivalent dose of Restasis™, the active control used in the study. TRIAL REGISTRATION: This trial was registered in the Clinical Trials Registry of India on 29/03/2019, and was assigned registration number CTRI/2019/03/018319.

Prolonged Inflammation and Infectious Changes in the Corneal Epithelium Are Associated with Persistent Epithelial Defect (PED).

Purpose: Failure of rapid re-epithelialization within 10-14 days after corneal injury, even with standard supportive treatment, is referred to as persistent corneal epithelial (CE) defect (PED). Though an array of genes regulates reepithelization, their mechanisms are poorly understood. We sought to understand the network of genes driving the re-epithelialization in PED. Method: After obtaining informed consent, patients underwent an ophthalmic examination. Epithelial scrapes and tears samples of six PED patients and six individuals (control) undergoing photorefractive keratectomy (PRK) were collected. RNA isolation and quantification were performed using either the epithelial scrape taken from PED patients or from HCLE cells treated with control tears or tears of PED patients. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression of a few important genes in CE homeostasis, inflammation, and cell-cell communication, viz., Kruppel-like factor 4 (KLF4), GPX4, IL6, TNFα, STING, IL8, desmoglein, and E-cadherin, among others. Their expressions were normalized with their respective housekeeping genes and fold changes were recorded. KLF4 localization and MMPs activity was carried out via immunofluorescence and zymography, respectively. Results: KLF4, a transcription factor important for CE homeostasis, was upregulated in tears-treated HCLE cells and downregulated in PED patients compared to the healthy PRK group. Cell-cell communication genes were also upregulated in tears-treated cells, whereas they were downregulated in the PED tissue group. Genes involved in proinflammation (IL6, 282-fold; TNFα, 43-fold; IL8, 4.2-fold) were highly upregulated in both conditions. MMP9 activity increased upon tears treatment. Conclusions: This study suggests that tears create an acute proinflammatory milieu driving the PED disease pathology, whereas the PED patients scrapes are an indicator of the chronic stage of the disease. Interferons, pro-inflammatory genes, and their pathways are involved in PED, which can be a potential target for inducing epithelialization of the cornea.

Corneal stem cells niche and homeostasis impacts in regenerative medicine; concise review.

The limbal stem cells niche (LSCN) is an optimal microenvironment that provides the limbal epithelial stem cells (LESCs) and strictly regulates their proliferation and differentiation. Disturbing the LSCN homeostasis can lead to limbal stem cell dysfunction (LSCD) and subsequent ocular surface aberrations, such as corneal stromal inflammation, persistent epithelial defects, corneal neovascularisation, lymphangiogenesis, corneal opacification, and conjunctivalization. As ocular surface disorders are considered the second main cause of blindness, it becomes crucial to explore different therapeutic strategies for restoring the functions of the LSCN. A major limitation of corneal transplantation is the current shortage of donor tissue to meet the requirements worldwide. In this context, it becomes mandatory to find an alternative regenerative medicine, such as using cultured limbal epithelial/stromal stem cells, inducing the production of corneal like cells by using other sources of stem cells, and using tissue engineering methods aiming to produce the three-dimensional (3D) printed cornea. Limbal epithelial stem cells have been considered the magic potion for eye treatment. Epithelial and stromal stem cells in the limbal niche hold the responsibility of replenishing the corneal epithelium. These stem cells are being used for transplantation to maintain corneal epithelial integrity and ultimately sustain optimal vision. In this review, we summarised the characteristics of the LSCN and their current and future roles in restoring corneal homeostasis in eyes with LSCD.

Single-Staged Surgical Correction of Eyelid Sequelae Along With Lid Margin Mucous Membrane Grafting in Stevens-Johnson Syndrome and Other Cicatricial Ocular Surface Diseases.

PURPOSE: The purpose of this study was to study the outcome of single-staged entropion surgery along with lid margin mucous membrane grafting for cicatrizing ocular surface disease. METHODS: Retrospective review of medical records of patients who underwent single-staged surgical correction of cicatricial entropion along with lid margin mucous membrane grafting for lid margin keratinization. RESULTS: Twenty-six eyes of 19 patients were studied. The mean age of patients was 42.5 years (standard deviation, SD-17.67), of which 7 patients were male and 12 were female. The most common disorder was Stevens-Johnson syndrome (SJS) sequelae (83.33%, n = 20), followed by mucous membrane pemphigoid (n = 4, 16.67%). The most common eyelid changes observed were cicatricial entropion in all 26 eyes (100%, n = 26), followed by trichiasis in 13 eyes (50%, n = 13). Lid margin keratinization was noted in all eyes. Postoperative improvement in corneal surface staining was noted in 70% of the patients (n = 13), no change in 20% of the patients (n = 4), and worsening of corneal surface staining in 10% of the patients (n = 2). Postoperative visual acuity improvement was noted in 50% of the eyes (n = 13), no improvement in 39% of the eyes (n = 10), and vision worsened in 12% of the eyes (n = 3). An entropion recurrence rate of 25% (n = 6) was observed over an average 10-month follow-up, whereas 75% (n = 20) reported no recurrence. CONCLUSIONS: Single-staged correction of eyelid cicatricial entropion with a lid margin mucous membrane graft (MMG) has promising outcomes in ocular surface diseases. It can decrease the need for multiple surgeries and provide symptomatic relief in patients with chronic cicatricial surface changes.

New horizons in aniridia management: Clinical insights and therapeutic advances.

Congenital aniridia is a rare genetic eye disorder characterized by the complete or partial absence of the iris from birth. Various theories and animal models have been proposed to understand and explain the pathogenesis of aniridia. In the majority of cases, aniridia is caused by a mutation in the PAX6 gene, which affects multiple structures within the eye. Treating these ocular complications is challenging and carries a high risk of side effects. However, emerging approaches for the treatment of aniridia-associated keratopathy, iris abnormalities, cataract abnormalities, and foveal hypoplasia show promise for improved outcomes. Genetic counseling plays a very important role to make informed choices. We also provide an overview of the newer diagnostic and therapeutic approaches such as next generation sequencing, gene therapy, in vivo silencing, and miRNA modulation.

Surgical Management of Peripheral Ulcerative Keratitis: Update on Surgical Techniques and Their Outcome.

Peripheral ulcerative keratitis (PUK) is an inflammatory, necrotic condition in the peripheral cornea which may end in corneal perforation and visual morbidity if not treated adequately. PUK can occur due to infectious or non-infectious causes. Early cases need medical therapy, both locally and systemically (for some cases). However, advanced PUK may necessitate surgical removal of inciting cause of the pathology and maintaining tectonic stability. Such surgical treatment, including corneal transplantations, may be used in an emergency setting or for visual rehabilitation following preliminary stabilization of the affected cornea. The outcome of these surgeries need to be analyzed to understand the long-term visual prognosis of such eyes. This is an attempt to analyze surgical modalities in the management of PUK and their outcomes.

Clinical and molecular aspects of congenital aniridia - A review of current concepts.

Congenital aniridia is a pan ocular disorder characterized by partial or total loss of iris tissue as the defining feature. Classic aniridia, however, has a spectrum of ocular findings, including foveal hypoplasia, optic nerve hypoplasia, nystagmus, late-onset cataract, glaucoma, and keratopathy. The latter three are reasons for further visual compromise in such patients. This entity is often due to mutations in the PAX6 (Paired box protein Pax-6) gene. Recently, aniridia-like phenotypes have been reported due to non-PAX6 mutations as in PITX2, FOXC1, FOXD3, TRIM44, and CYP1B1 as well wherein there is an overlap of aniridia, such as iris defects with congenital glaucoma or anterior segment dysgenesis. In this review, we describe the various clinical features of classic aniridia, the comorbidities and their management, the mutation spectrum of the genes involved, genotype-phenotype correlation of PAX6 and non-PAX6 mutations, and the genetic testing plan. The various systemic associations and their implications in screening and genetic testing have been discussed. Finally, the future course of aniridia treatment in the form of drugs (such as ataluren) and targeted gene therapy has been discussed.

Role of AS-OCT in Managing Corneal Disorders.

Optical coherence tomography (OCT) is analogous to ultrasound biometry in the cross sectional imaging of ocular tissues. Development of current devices with deeper penetration and higher resolution has made it popular tool in clinics for visualization of anterior segment structures. In this review, the authors discussed the application of AS-OCT for diagnosis and management of various corneal and ocular surface disorders. Further, recent developments in the application of the device for pediatric corneal disorders and extending the application of OCT angiography for anterior segment are introduced.