Prevalence and risk factors of pterygium: a systematic review and meta-analysis

Genome-wide methylation analysis unveils genes and pathways with altered methylation profiles in pterygium

Pterygium is a highly prevalent ocular surface disease, particularly in equatorial regions, with no pharmaceutical intervention available and surgical excision remaining the only treatment option. Ultraviolet (UV) radiation from sunlight is widely recognized as the primary cause of pterygium. While chronic UV exposure induces epigenetic changes in the skin contributing to skin cancer, comprehensive studies on epigenetic alterations in pterygium remain unpublished, and causal relationships have yet to be established. This study aimed to investigate genome-wide methylation changes in pterygium using the Illumina Infinium Epic v2.0 Methylation array. We identified 1052 hypermethylated CpGs (499 genes) and 687 hypomethylated CpGs (340 genes) in pterygium tissue compared to control conjunctival tissue from patients undergoing cataract surgery (Δβ>|0.1|, P < 0.05). Hypomethylated genes were mainly associated with PI3K-Akt and MAPK pathways, while hypermethylated genes were enriched in pathways related to oxidative stress, autophagy, DNA repair, and Wnt signaling inhibition. Comparing these findings with transcriptomic datasets revealed 28 hypermethylated genes with downregulated transcripts and 74 hypomethylated genes with upregulated transcripts. qPCR validation confirmed upregulation of hypomethylated genes (MMP2, FBLN5, ZEB1) and downregulation of hypermethylated genes (SAMSN1, CBX4) at the transcript level. These findings suggest that dysregulated DNA methylation may contribute to pterygium pathogenesis by upregulating genes involved in cell proliferation, survival, angiogenesis, fibrosis, and extracellular matrix remodeling, while silencing genes associated with oxidative stress response, autophagy, and DNA damage repair. These insights into the global methylation landscape of pterygium open avenues for detailed functional analysis, potentially guiding targeted therapeutic strategies.

Long-Term Clinical Outcomes After Femtosecond Laser-Assisted Pterygium Excision

PURPOSE

To report the long-term recurrence and complication rates after femtosecond laser-assisted pterygium excision surgery (FLAPS) with conjunctival autograft surgery.

METHODS

Single-center retrospective study of consecutive cases of primary nasal and/or temporal pterygia who underwent primary pterygium excision surgery with femtosecond laser-assisted conjunctival autograft. All subjects underwent manual pterygium excision, followed by femtosecond laser (Femto LDV Z8)-assisted conjunctival autograft surgery and with follow-up duration up to 5 years. Recurrence was defined as appearance of secondary pterygium at the same location. All complications intra- and postoperative were recorded. Primary outcome measure was postoperative pterygia recurrence, and secondary outcomes assessed were the intra- and postoperative complication rates associated with FLAPS.

RESULTS

We included 277 sequential FLAPS performed from September 2016 to September 2024. At baseline, mean (SD) age was 62.8 years (13.9); 183 males (66.1%); mean best-corrected visual acuity (BCVA) logMAR 0.23 [0.29]. A total of 200 (72.2%) were of Chinese ethnicity, with 3 (1.2%), 14 (4.9%), and 60 (21.6%) being Indian, Malay, or others. Recurrence was seen in 2/277 patients (0.72%) at 12 and 21 months, respectively, both of which were nasal pterygia, because of glue failure, but declined repeat excision surgery. There were no differences in postoperative BCVA, applanation duration, graft depth, or graft area between the groups. Cox regression analysis showed no significant association between pterygia grade or side with recurrence. Overall 5 years probability to be recurrence free was 99.20%. Five patients (1.8%) experienced dry eyes postoperatively. No intraoperative complications were seen.

CONCLUSIONS

Primary pterygium excision with femtosecond laser-assisted conjunctival autograft results in low rates of recurrence and complications.

Long-Term Outcomes of Pterygium Extended Removal Combined with Conjunctival Autograft and Amniotic Membrane Transplantation

PURPOSE

To observe the Long-term results of pterygium extended removal combined conjunctival autograft and amniotic membrane transplantation.

METHODS

This is a prospective study of 666 eyes (606 patients, 332 right eyes and 336 left eyes). All patients underwent pterygium extended removal combined conjunctival autograft and amniotic membrane transplantation in a same hospital. The primary outcome measures included the cosmetic appearances and recurrence rate; the secondary outcome measures were some serious complications, like Keratitis, conjunctival cyst and conjunctival granuloma.

RESULTS

606 patients (82.34% of surviving) were able to be followed up. The mean follow-up period was 29.96 ± 13.34 months. Recurrence was noted in 7 eyes (1.05%), and there were no serious complications. 89.04% of eyes were graded as having excellent cosmetic appearance.

CONCLUSIONS

The long-term recurrence rate of pterygium extended removal combined conjunctival autograft and amniotic membrane Graft is very low, and the long-term cosmetic appearance is excellent. And also, there were no other serious complications.

Classification of ocular surface diseases: Deep learning for distinguishing ocular surface squamous neoplasia from pterygium

PURPOSE

Given the significance and potential risks associated with Ocular Surface Squamous Neoplasia (OSSN) and the importance of its differentiation from other conditions, we aimed to develop a Deep Learning (DL) model differentiating OSSN from pterygium (PTG) using slit photographs.

METHODS

A dataset comprising slit photographs of 162 patients including 77 images of OSSN and 85 images of PTG was assembled. After manual segmentation of the images, a Python-based transfer learning approach utilizing the EfficientNet B7 network was employed for automated image segmentation. GoogleNet, a pre-trained neural network was used to categorize the images into OSSN or PTG. To evaluate the performance of our DL model, K-Fold 10 Cross Validation was implemented, and various performance metrics were measured.

RESULTS

There was a statistically significant difference in mean age between the OSSN (63.23 ± 13.74 years) and PTG groups (47.18 ± 11.53) (P-value =.000). Furthermore, 84.41% of patients in the OSSN group and 80.00% of the patients in the PTG group were male. Our classification model, trained on automatically segmented images, demonstrated reliable performance measures in distinguishing OSSN from PTG, with an Area Under Curve (AUC) of 98%, sensitivity, F1 score, and accuracy of 94%, and a Matthews Correlation Coefficient (MCC) of 88%.

CONCLUSIONS

This study presents a novel DL model that effectively segments and classifies OSSN from PTG images with a relatively high accuracy. In addition to its clinical use, this model can be potentially used as a telemedicine application.

A systematic review of the potential treatment effects of topical epidermal growth factor for ocular surface disorders

PURPOSE

This systematic review, evaluated the role of epidermal growth factor (EGF) in corneal wound healing and the pathogenesis of ocular surface disorders (OSDs).

METHODS

The clinical and experimental application of topical EGF therapy for OSDs was reviewed. This systematic research assessed articles published on PubMed/MEDLINE from 2000 to 2023 and summarized and discussed the findings of 38 experimental and 10 clinical studies. Reporting adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

The role of EGF and its receptor (EGFR) is indispensable in corneal wound healing after injury. The most important downstream molecular pathways are the MAPK/Erk and PI3K/Akt pathways, which lead to proliferation, migration, and differentiation of corneal epithelial cells. Other EGF-related pathways, such as Decorin and Erk signaling (decreasing Pax6), as well as upregulating VEGF, contribute to early and late remodeling after corneal healing. The effect of EGF on corneal wound healing is dose-dependent, and it interacts with other important pathways, such as TGF-β.

CONCLUSIONS

There are several studies on animals and humans that showed promise for topical EGF therapy in the form of drops, ointments, or loaded contact lenses for a variety of OSDs, such as dry eye disease, neurotrophic ulcers, and pterygium excision. The reported OSDs after using EGFR inhibitors for oncology patients, and their favorable response to topical EGF therapy, further support the significance of EGF in the pathogenesis and treatment of OSDs. However, current clinical evidence is scarce, and high-quality studies are warranted to confirm the therapeutic role of EGF topical treatment for a variety of OSDs and determine the most effective yet safe concentrations.

Potential Role of Malassezia restricta in Pterygium Development

Pterygium is a condition affecting the ocular surface, marked by a triangular-shaped growth of fibrotic tissue extending from the nasal conjunctiva toward the corneal center, potentially causing visual impairment. While ultraviolet (UV )light exposure is the primary risk factor for pterygium, its underlying cause remains unclear. In order to better understand the true genesis of pterygium development, we investigated pterygium tissue and compared it with healthy conjunctiva controls. Given the eye's direct environmental exposure, we analyzed the microbiota composition using metagenomic sequencing of pterygium tissue to identify microbes potentially associated with this condition. Metagenomic sequencing revealed a higher prevalence of the fungus Malassezia restricta in five pterygium samples, confirmed by in situ hybridization. The CHIT1 gene, which plays a role in antifungal defenses, displayed the highest expression in five pterygium tissue samples compared to healthy conjunctiva controls, suggesting the potential involvement of Malassezia restricta in pterygium development. Gene expression profiling of pterygium highlighted an IL-33 and IL-4 gene expression signature, along with an increased presence of M2 macrophages, emphasizing their role in promoting fibrosis-a hallmark feature of pterygium. The detection of Malassezia restricta in the pterygium samples and associated molecular changes provides novel insights into the ocular microbiome and raises the possibility of Malassezia's involvement in pterygium pathology.

A semantic segmentation-based automatic pterygium assessment and grading system

Introduction

Pterygium, a prevalent ocular disorder, requires accurate severity assessment to optimize treatment and alleviate patient suffering. The growing patient population and limited ophthalmologist resources necessitate efficient AI-based diagnostic solutions. This study aims to develop an automated grading system combining deep learning and image processing techniques for precise pterygium evaluation.

Methods

The proposed system integrates two modules: 1) A semantic segmentation module utilizing an improved TransUnet architecture for pixel-level pterygium localization, trained on annotated slit-lamp microscope images from clinical datasets. 2) A severity assessment module employing enhanced curve fitting algorithms to quantify pterygium invasion depth in critical ocular regions. The framework merges deep learning with traditional computational methods for comprehensive analysis.

Results

The semantic segmentation model achieved an average Dice coefficient of 0.9489 (0.9041 specifically for pterygium class) on test datasets. In clinical validation, the system attained 0.9360 grading accuracy and 0.9363 weighted F1 score. Notably, it demonstrated strong agreement with expert evaluations (Kappa coefficient: 0.8908), confirming its diagnostic reliability.

Discussion

The AI-based diagnostic method proposed in this study achieves automatic grading of pterygium by integrating semantic segmentation and curve fitting technology, which is highly consistent with the clinical evaluation of doctors. The quantitative evaluation framework established in this study is expected to meet multiple clinical needs beyond basic diagnosis. The construction of the data set should continue to be optimized in future studies.

Decreased PAX6 and DSG1 Protein Expression in Corneal Epithelium of Patients with Epithelial Basal Membrane Dystrophy, Salzmann Nodular Degeneration, and Pterygium

Background/Objectives: Evaluation of stem cell, keratin, retinoic acid metabolism markers and non-coding micro-RNAs (miRNAs) in conjunctival and corneal samples of patients with epithelial basal membrane dystrophy (EBMD), Salzmann nodular degeneration (SND), pterygium and congenital aniridia (CA), to detect similarities and differences in their pathogenesis. Methods: Impression cytology (IC) samples and corneal epithelial samples (CEs) of patients with EBMD, SND, pterygium, congenital aniridia, and healthy control subjects have been analyzed. The IC samples were subjected to qPCR, and the epithelial samples were subjected to qPCR and WB. Limbal epithelial stem cell markers, keratins, retinoic acid metabolism markers, and miRNAs were analyzed. Results: In conjunctival IC samples, PAX6 mRNA expression was significantly lower in EBMD, SND, pterygium, and CA compared to healthy controls (p ≤ 0.02). KRT13 mRNA expression was significantly higher in EBMD, SND, and pterygium (p ≤ 0.018), and FABP5 was increased in pterygium samples (p = 0.007). MiRNA-138-5p was significantly higher in aniridia samples than in normal controls (p = 0.037). In corneal epithelial samples, PAX6 protein, DSG1 mRNA and protein, miRNA-138-5p, and miR-204-5p expression were significantly lower in EBMD, SND, and pterygium samples than in controls (p ≤ 0.02). ALDHA1 mRNA expression was significantly lower (p < 0.0001), and FABP5 mRNA expression was significantly higher (p = 0.014) in pterygium samples than in controls. Conclusions: PAX6, DSG1, miR-138-5p, and miR-204-5p expression is decreased in the corneal epithelium of epithelial basal membrane dystrophy, Salzmann nodular degeneration, and pterygium subjects. In addition, there is a dysregulation of markers of the retinoic acid signaling pathway, such as ADH1A1 and FABP5, in the corneal epithelium of pterygium subjects. These changes may offer therapeutic targets in the treatment of these ocular surface diseases.

Identification of biomarkers and immune microenvironment associated with pterygium through bioinformatics and machine learning

Background

Pterygium is a complex ocular surface disease characterized by the abnormal proliferation and growth of conjunctival and fibrovascular tissues at the corneal-scleral margin. Understanding the underlying molecular mechanisms of pterygium is crucial for developing effective diagnostic and therapeutic strategies.

Methods

To elucidate the molecular mechanisms of pterygium, we conducted a differential gene expression analysis between pterygium and normal conjunctival tissues using high-throughput RNA sequencing. We identified differentially expressed genes (DEGs) with statistical significance (adjust p < 0.05, |logFC| > 1). Enrichment analyses were performed to assess the biological processes and signaling pathways associated with these DEGs. Additionally, we utilized weighted correlation network analysis (WGCNA) to select module genes and applied Random Forest (RF) and Support Vector Machine (SVM) algorithms to identify pivotal feature genes influencing pterygium progression. The diagnostic potential of these genes was validated using external datasets (GSE2513 and GSE51995). Immune cell infiltration analysis was conducted using CIBERSORT to compare immune cell populations between pterygium and normal conjunctival tissues. Quantitative PCR (qPCR) was used to confirm the expression levels of the identified feature genes. Furthermore, we identified key miRNAs and candidate drugs targeting these feature genes.

Results

A total of 718 DEGs were identified in pterygium tissues compared to normal conjunctival tissues, with 254 genes showing upregulated expression and 464 genes exhibiting downregulated expression. Enrichment analyses revealed that these DEGs were significantly associated with inflammatory processes and key signaling pathways, notably leukocyte migration and IL-17 signaling. Using WGCNA, RF, and SVM, we identified KRT10 and NGEF as pivotal feature genes influencing pterygium progression. The diagnostic potential of these genes was validated using external datasets. Immune cell infiltration analysis demonstrated significant differences in immune cell populations between pterygium and normal conjunctival tissues, with an increased presence of M1 macrophages and resting dendritic cells in pterygium samples. qPCR analysis confirmed the elevated expression of KRT10 and NGEF in pterygium tissues.

Conclusion

Our findings emphasize the importance of gene expression profiling in unraveling the pathogenesis of pterygium. The identification of pivotal feature gene KRT10 and NGEF provide valuable insights into the molecular mechanisms underlying pterygium progression.

In vivo confocal microscopy findings about ocular surface recovery in patients following pterygium excision combined with conjunctival autograft

PURPOSE

To study cellular and neural changes around the donor and recipient areas after pterygium excision combined with autologous conjunctival transplantation using corneal confocal microscopy, we evaluated the postoperative impact of this surgical procedure.

METHODS

Patients with primary pterygium located on the nasal side who visited the Department of Ophthalmology of Wuxi Second People's Hospital between April and August 2023 were enrolled. Age-matched healthy eyes were included as the control group. IVCM was performed in the affected eyes, 6 months after pterygium excision. The images of the central conjunctival cells in the recipient and donor areas, the cells of each layer of the cornea around the recipient and donor area (around 2 mm from the nasal and upper corneal margins), and the structures of the corneal margins were recorded in the affected eyes and statistically compared with the corresponding areas in the control eyes.

RESULTS

Seventeen eyes of 14 patients with primary pterygium located on the nasal side (mean 64 ± 8.74 years old), and 17 eyes of nine patients as age-matched normal controls were included. Compared with those of normal eyes, the density of corneal pterygoid epithelium around the recipient area (5104 ± 599 cells/mm2 vs. 5700 ± 515 cells/mm2, P < 0.01) and the central conjunctival epithelial cells in the recipient areas (3984 ± 453 cells/mm2 vs. 4834 ± 244 cells/mm2, P < 0.01) were significantly lower 6 months postoperatively. However, the superficial stromal, deep stromal, and endothelial cell densities around the recipient area exhibited no significant differences (P > 0.05). Highly illuminated basal cells were visible at the nasal corneal margin, with an irregular intersection of fibrous tissue with corneal epithelial cells. More dendritic Langerhans cell infiltration was seen in the junctional area. Compared with those in the normal eyes, the densities of the corneal pterygoid epithelium (4896 ± 428 cells/mm2 vs. 5557 ± 367 cells/mm2, P < 0.01), deep stromal cells (337 ± 65 cells/mm2 vs. 419 ± 39 cells/mm2, P < 0.01), endothelial cells (2305 ± 170 cells/mm2 vs. 2547 ± 212 cells/mm2, P < 0.01) around the donor area and the central conjunctival epithelial cells (3700 ± 446 cells/mm2 vs. 4282 ± 272 cells/mm2, P < 0.01) in the donor area were significantly lower 6 months postoperatively. However, no significant differences were observed in superficial stromal cell density (P > 0.05). A slight wavy interfacial intersection was visible on the superior corneal margin, with some of the highlighted basal cells visible.

CONCLUSIONS

Pterygium excision combined with autologous conjunctival transplantation with corneal stem cells can better promote the repair of most corneal cells around the recipient area and fence-like structures of the corneal rim 6 months postoperatively, but there may be some damage to the corneal conjunctival structures around the donor area.

Evaluation of the clinical efficacy of modified LSC transplantation plus BCL implantation in the treatment of pterygium

OBJECTIVE

To explore the clinical efficacy of modified limbal stem cell transplantation(Modified LSC transplantation) and bandage contact lens(BCL) implantation in pterygium surgery.

METHODS

A total of 479 patients with primary pterygium who were admitted to our hospital from March 2019 to March 2023 were randomly divided into three groups: the normal group (Group A: 89 patients), the control group (Group B: 195 patients), and the modified group (Group C: 195 patients). Each group received different intervention measures. Group A did not undergo surgical treatment and were required to follow up as outpatients. Group B received LSC transplantation combined with interrupted suturing plus BCL, whereas Group C received modified LSC transplantation combined with BCL. The degree of corneal irritation symptoms, wound healing and graft status under slit lamp, incidence and recurrence rate of complications, tear film rupture time, tear secretion test, intraocular pressure, ocular surface inflammation response(IL-1β, PGE2, TNF-α, VEGF), and visual quality were compared and analyzed at various time points after surgery.

RESULTS

Compared with those in the Group B, patients in the Group C experienced faster normalization of corneal epithelium recovery, fewer corneal irritation symptoms, and better wound healing. The break-up time (BUT) of the tear film at 1 week to 1 year postoperatively was significantly greater in the Group C than Group B, with values approaching those of Group A by 3 months (P < 0.05). The Schirmer test results revealed a similar trend to that of the BUT. Further analysis of intraocular pressure (IOP) at different time points revealed no significant differences among the three groups at postoperative Day 1. However, due to the use of corticosteroid eye drops postoperatively, IOP was greater in both the Group B(17.24 ± 2.12 mmHg) and Group C (17.02 ± 2.37 mmHg) than Group A (13.92 ± 1.57 mmHg) at 1 week. By 1 month, Group C had a lower IOP (15.77 ± 1.63 mmHg) than Group B(17.78 ± 2.41 mmHg). There were no significant differences in IOP among the three groups from 3 months to 1 year (P > 0.05). The ELISA results indicated that the expression levels of the ocular surface inflammatory factors IL-1β, TNF-α, PEG2, and VEGF in the Group C were lower than those in Group B from 1 week to 1 year post surgery. Under both natural light and low-light conditions (spatial frequency/6 cd), Group C had better best-corrected visual acuity and contrast sensitivity than Group B at 1 week to 1 year postoperatively. Additionally, Group C had lower corneal higher-order aberrations (including astigmatism, spherical aberrations, and total higher-order aberrations) and superior vision-related quality of life scores at 1 year postoperatively than Group B, with statistically significant differences (P < 0.05).

CONCLUSION

Modified LSC transplantation combined with BCL implantation provided superior treatment outcomes for patients with pterygium, which was worthy of further clinical promotion.

Comparison of Biomarkers Playing a Role in Pterygium Development in Pterygium and Recurrent Pterygium Tissues

Background/Objectives: Pterygium is a nonneoplastic elastotic degeneration characterized by subepithelial growth. It manifests as an ocular lesion originating from the bulbar conjunctiva, extending to the corneal surface, and reaching the visual axis in some cases. Although the exact cause is unknown, prolonged exposure to ultraviolet radiation is considered the most significant contributing factor. Chronic irritation and actinic damage are likely responsible for the typical fibrovascular reactions observed in pterygium. Additionally, growth factors, cytokines, and matrix metalloproteinases play roles in the pathogenesis of pterygium. This study compared recurrent and primary pterygium cases at the molecular level to gain new insights into the etiology of pterygium. Methods: Total protein was extracted from surgical samples of patients with primary and recurrent pterygium, and the levels of transforming growth factor beta 1 (TGF-β1), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), IL-8, and IL-10 were analyzed using the enzyme-linked immunosorbent assay technique. Target gene expression levels were analyzed using the ΔΔCt method after cDNA synthesis from isolated RNA, with normalization to GAPDH and quantification performed with SYBR Green PCR Master Mix. Results: Among the studied cytokines, IL-10 levels were higher in primary pterygium than in recurrent pterygium (722.0 ± 600.9/421.4 ± 266.8) (p = 0.0054). Other cytokines (IL-6, IL-8, IL-1β, and TGF-β1) were detected at similar levels in both primary and recurrent pterygium (p = 0.2986). Additionally, the TGF-β1 gene expression was found to be significantly upregulated in recurrent pterygium tissue compared to primary pterygium tissue (p = 0.034). Conclusions: This increase suggests that TGF-β1 may contribute to the recurrence mechanisms of pterygium through processes such as fibroblast activation and tissue remodeling. The higher levels of IL-10 in primary pterygium compared to recurrent pterygium indicate an enhanced early protective response aimed at limiting pterygium progression and controlling the inflammatory process.

Unravelling the molecular tapestry of pterygium: insights into genes for diagnostic and therapeutic innovations

Pterygium, an ocular surface disorder, manifests as a wing-shaped extension from the corneoscleral limbus onto the cornea, impacting vision and causing inflammation. With a global prevalence of 12%, varying by region, the condition is linked to UV exposure, age, gender, and socioeconomic factors. This review focuses on key genes associated with pterygium, shedding light on potential therapeutic targets. Matrix metalloproteinases (MMPs), especially MMP2 and MMP9, contribute to ECM remodelling and angiogenesis in pterygium. Vascular endothelial growth factor (VEGF) plays a crucial role in angiogenesis and is elevated in pterygium tissues. B-cell lymphoma-2, S100 proteins, DNA repair genes (hOGG1, XRCC1), CYP monooxygenases, p53, and p16 are implicated in pterygium development. A protein-protein interaction network analysis highlighted 28 edges between the aforementioned proteins, except for VEGF, indicating a high level of interaction. Gene ontology, microRNA and pathway analyses revealed the involvement of processes such as base excision repair, IL-17 and p53 signalling, ECM disassembly, oxidative stress, hypoxia, metallopeptidase activity and others that are essential for pterygium development. In addition, miR-29, miR-125, miR-126, miR-143, miR-200, miR-429, and miR-451a microRNAs were predicted, which were shown to have a role in pterygium development and disease severity. Identification of these molecular mechanisms provides insights for potential diagnostic and therapeutic strategies for pterygium.

The Effect of Amniotic Membrane Transplantation or Conjunctival Autografts on the Tear Mucins MUC5A and MUC2 After Pterygium Resection: A Six-Month Follow-Up

Purpose

Pterygium is an ocular surface disease characterized by the invasion of fibrovascular tissue from the bulbar conjunctiva to the cornea and is associated with abnormal tear function caused by changes in tear composition and osmolarity. In this study, the effect of two different surgical techniques to remove primary pterygium: conjunctival autograft surgery (CAG) and amniotic membrane transplantation (AMT), on changes in MUC2 and MUC5AC tear mucins concentration were evaluated.

Methods

Forty-four patients (>18 years old) with primary unilateral pterygium (> 1.0 mm long, measured from the limbus to the apex on the cornea) were randomly enrolled, and assigned to the AMT or CAG group by using the permuted block technique. Patients with systemic inflammatory diseases or other eye comorbidities were excluded from the study. Tear break-up time (TBUT) and best-corrected visual acuity (BCVA) assessments were performed before surgery and at 1, 3, and 6 months after surgery. Tears were collected concurrently with the clinical evaluations, and MUC2 and MUC5AC concentrations were subsequently measured by means of ELISA.

Results

At 6 months after CAG or AMT, TBUT and BCVA were significantly lower (P < 0.05) in comparison with the baseline values in the study subjects. The tear mucin concentrations of both MUC2 and MUC5AC were significantly higher (P < 0.0001) in patients with pterygium before any surgical procedure than in healthy individuals. The concentration of MUC2 increased at 1 and 3 months after CAG surgery and decreased at 6 months; however, the MUC2 concentration decreased on the AMT group in all time point measurements. Interestingly, the MUC5AC concentration significantly increased at 1 month after AMT or CAG and then decreased at 3 and 6 months after surgery. Finally, an inverse correlation was found between both MUC2 and MUC5AC tear mucins concentration and the TBUT.

Conclusions

These results suggest that pterygium excision via both CAG or AMT changes the concentrations of the tear mucins MUC2 and MUC5AC during the evaluated times, and these changes could affect tear film stability and clinical recovery after pterygium treatment.

Translational Relevance

The tear film stability during pterygium excision was evaluated to determine adequate treatments.

Ocular Mucous Membrane Pemphigoid Presenting as Recurrent Pterygium

PURPOSE

The aim of this series was to report recurrent pterygium as a presenting feature of ocular mucous membrane pemphigoid (oMMP).

METHODS

A retrospective review was performed, and patients with biopsy positive oMMP who presented with recurrent pterygia were included. Data on the demographic profile, clinical characteristics, and details of the surgical intervention were collected.

RESULTS

A total of 5 patients with recurrent pterygium were included. All the patients were men. The median age was 63 years. History of pterygium surgery was present in 8/10 eyes (80%), of which 6 eyes (60%) developed a recurrent pterygium. A symblepharon was present in 4/6 eyes (67%). Forniceal shortening was present in 10/10 (100%) eyes. All eyes were subjected to a conjunctival biopsy for direct immunofluorescence, of which 9 eyes (90%) had positive results consistent with oMMP. Systemic immunomodulatory therapy (IMT) with either methotrexate or azathioprine was initiated in all 5 patients.

CONCLUSIONS

Recurrent pterygium can be a presenting feature of oMMP. The presence of symblepharon formation or forniceal shortening, especially in the fellow eye, warrants a conjunctival biopsy and prompt initiation of IMT to prevent disease progression.

Efficacy of outdoor interventions for myopia in children and adolescents: a systematic review and meta-analysis of randomized controlled trials

Objectives

The objective of this systematic review and meta-analysis was to evaluate the overall efficacy of outdoor interventions for myopia in children and adolescents, and to provide evidence for the prevention and control of myopia.

Methods

Randomized controlled trials of outdoor interventions for myopia in children and adolescents were identified using electronic databases and manual searches. The Revised Cochrane risk-of-bias tool for randomized trials (RoB 2) was used to assess risk of bias in randomized controlled trials. A mean difference (MD) and a risk ratio (RR) with a 95% confidence interval (CI) were used to combine effect sizes. A sensitivity analysis was performed for each outcome using a stepwise elimination method to assess whether the pooled results were significantly affected by individual studies.

Results

The analysis included seven randomized controlled trials involving a total of 9,437 subjects. The meta-analysis showed marked and statistically significant improvements in spherical equivalent refraction (MD = 0.19; 95% CI 0.14 to 0.25; p < 0.01), axial length (MD = -0.09; 95% CI -0.13 to -0.05; p < 0.01), and myopia incidence (RR = 0.84; 95% CI 0.78 to 0.91; p < 0.01) following outdoor interventions.

Conclusion

Outdoor interventions effectively contributed to the prevention and control of myopia in children and adolescents, positively impacting spherical equivalent refraction, axial length, and myopia incidence. Outdoor interventions were characterized by low risk and high therapeutic benefits and could serve as alternative or adjuvant approaches to medication for the treatment of myopia. Considering the advantages in terms of safety and efficacy, outdoor interventions may be considered as a preferred intervention for the treatment of myopia in children and adolescents, while susceptibility to diseases associated with sunlight, particularly UV exposure, must be taken into account.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, Identifier CRD42024538695.

Granzyme B Expression in Conjunctiva of Patients with Pterygium

Pterygium is often associated with chronic ultraviolet (UV) radiation exposure and characterized by the overgrowth of conjunctiva and extracellular matrix (ECM) remodeling. Notably, several studies in the skin have demonstrated that chronic UV radiation can upregulate Granzyme B (GrB) expression and increase ECM degradation. The aim of this study was to compare GrB expression between pterygium and healthy controls and to further link this GrB expression to mast cells. Post-mortem pterygium tissues and conjunctival tissues from age-matched controls were used to assess GrB expression via immunofluorescence and microscopy. We found a significantly higher density of GrB+ cells from pterygium specimens compared to healthy controls. Furthermore, many of the GrB+ cells in pterygium specimens co-expressed tryptase, a mast cell marker. These findings suggest a role for conjunctival mast cell-secreted GrB in the pathogenesis of pterygium and highlight GrB as a possible therapeutic target in delaying or halting pterygium progression.

Integrative analysis of ex vivo studies and microarray reveals the novel inhibitor effects of trehalose on the pathogenesis of pterygium

Pterygium is a frequent eye surface condition that is characterized by a high rate of proliferation, fibrovascular development, cellular migration, corneal infiltration, and angiogenesis. We investigated that ex vivo primary pterygium and conjunctival cell cultures were generated to analyze the effect of trehalose on cellular proliferation. After trehalose treatment, we performed microarray analysis to evaluate changes in the mRNA profile. We analyzed gene ontology (GO) and KEGG pathways to identify hub genes that changed expression levels after treatment and were associated with pterygium development. We selected three genes to verify their expression levels using qRT-PCR. The study also evaluated the impact of trehalose treatment on cell migration through a wound-healing assay. Our results suggested that pterygium cell proliferation was inhibited in a dose-dependent manner by trehalose. 2354 DEG were identified in pterygium and conjunctiva cells treated with trehalose compared to untreated groups. Functional enrichment analysis showed that differentially expressed mRNAs are involved in proliferation, vasculature development, and cell migration. We identified ten hub genes including upregulated (RANBP3L, SLC5A3, RERG, ANKRD1, DHCR7, RAB27B, GPRC5B, MSMO1, ASPN, DRAM1) and downregulated (TNC, PTGS2, GREM2, NPTX1, NR4A1, HMOX1, CXCL12, IL6, MYH2, TXNIP). Microarray analysis and functional investigations suggest that trehalose affects the pathogenesis of pterygium by modifying the expression of genes involved in crucial pathways related to cell function.

A Phase IIa Multicenter, Randomized, Vehicle-Controlled, Dose Escalating Study to Evaluate the Safety, Efficacy, and Pharmacokinetics of CBT-001 Ophthalmic Solution in Patients With Primary or Recurrent Pterygium

Purpose

To evaluate the safety and efficacy of CBT-001, a multitarget tyrosine kinase inhibitor eyedrop, for pterygia.

Design

Phase II clinical trial. Stage 1 was a single center, open-labeled, vehicle-controlled study. Stage 2 was a multicenter, randomized, double-masked, vehicle-controlled trial.

Participants

Patients with primary or recurrent pterygia.

Main Outcome Measures

The primary efficacy end point was lesion vascularity based on masked grading of photographs by an independent reading center. Other end points included dimensions of pterygia and safety.

Methods

In stage 1, 24 eyes of 24 patients received 1 drop of CBT-001 in a dose escalation fashion (0.02%, 0.05%, and 0.2%) to determine the maximally tolerated dose based on adverse events (AEs) and blood drug levels. In stage 2, subjects were randomly assigned to receive the maximally tolerated dose of CBT-001 or vehicle dosed 3 times a day for 4 weeks with a 20-week follow-up.

Results

In stage 1, the plasma maximum concentration values for all doses of CBT-001 were at or below the limit of detection (0.01 ng/ml). The most commonly reported AEs were mild foreign body sensation and irritation. CBT-001 0.2% was evaluated in stage 2. Baseline demographic characteristics were similar between patients receiving CBT-001 (n = 25) and vehicle (n = 23). After 4 weeks of dosing, the mean change from baseline in pterygium vascularity scores was -0.8 ± 0.7 (mean ± standard deviation) in subjects receiving CBT-001 0.2% and 0.0 ± 0.5 in subjects receiving vehicle (P < 0.001; 95% confidence interval: -1.12, -0.40). Pterygium vascularity scores remained significantly decreased, after the 4-week dosing period, at weeks 8 and 16, but not at week 24. The mean changes from baseline in the length of the pterygia were also significantly lower in subjects receiving CBT-001 compared with vehicle at weeks 2, 4, and 8 (P ≤ 0.014). The most commonly reported AEs were ocular, mild in severity, resolved after therapy, and did not result in discontinuation.

Conclusions

CBT-001 0.2% decreased pterygia vascularity and lesion length after 4 weeks of dosing with a prolonged effect after dosing. The drug was well tolerated with minimal detected systemic drug levels.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Inflammation due to ocular surface homeostasis imbalance caused by pterygia: tear lymphotoxin-alpha study and a literature review

OBJECTIVE

To estimate the pterygium ocular surface state, and compare with healthy eyes and dry eyes. To investigate the inflammation due to pterygia growth by tear Lymphotoxin-alpha (LT α) test.

DESIGN

Prospective, single-center study.

PARTICIPANTS

400 patients, divided into 100 pterygium group, 100 mild dry eye group, 100 moderate dry eye group, and 100 age-and sex-matched normal controls.

METHODS

The non-invasive break-up time (NIBUT), tear meniscus height (TMH) test, corneal fluorescein staining (CFS), meibomian gland loss score (MGs), and lipid layer thickness (LLT) were evaluated in all patients. Pterygium status and ocular status in the pterygium group were collected. The tear LT α test was conducted in the pterygium patients group.

RESULT

Pterygium can affect the ocular surface, leading to decreased tear film stability. The TMH, NIBUT, CFS, MGs, and lipid layer thickness can provide insights into this phenomenon. The presence of pterygium can change the structure and condition of the ocular surface. Tear LT α testing shows an abnormal decrease in LT α levels in pterygium patients. This indicates an immune-inflammation microenvironment that causes tissue repair deficiency.

CONCLUSION

The dry eye triggered by the growth of pterygium may originate from the tear film instability due to pterygia. As an inflammatory index, LT α in the development of pterygium and the aggravation of dry eye patients can indicate that the ocular surface is in different inflammatory states. Future tear testing in LT α may be a potential indicator to assess the inflammatory status of the dry eye.

Assessing the safety of new germicidal far-UVC technologies

The COVID-19 pandemic underscored the crucial importance of enhanced indoor air quality control measures to mitigate the spread of respiratory pathogens. Far-UVC is a type of germicidal ultraviolet technology, with wavelengths between 200 and 235 nm, that has emerged as a highly promising approach for indoor air disinfection. Due to its enhanced safety compared to conventional 254 nm upper-room germicidal systems, far-UVC allows for whole-room direct exposure of occupied spaces, potentially offering greater efficacy, since the total room air is constantly treated. While current evidence supports using far-UVC systems within existing guidelines, understanding the upper safety limit is critical to maximizing its effectiveness, particularly for the acute phase of a pandemic or epidemic when greater protection may be needed. This review article summarizes the substantial present knowledge on far-UVC safety regarding skin and eye exposure and highlights research priorities to discern the maximum exposure levels that avoid adverse effects. We advocate for comprehensive safety studies that explore potential mechanisms of harm, generate action spectra for crucial biological effects and conduct high-dose, long-term exposure trials. Such rigorous scientific investigation will be key to determining safe and effective levels for far-UVC deployment in indoor environments, contributing significantly to future pandemic preparedness and response.

The effect of different pterygium surgery techniques on the ocular surface parameters in different durations: a systematic review and meta-analysis

PURPOSE

To evaluate the effects of different pterygium surgery techniques on ocular surface (OS) in different follow-up periods.

METHODS

PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wan Fang, and China Biology Medicine disc were searched for studies reporting pre- and post-operative OS parameters in pterygium.

RESULTS

A total of 33 articles were finally included. Three OS parameters showed relatively consistent changing trends after surgery including ocular surface disease index (OSDI), tear film break-up time (BUT), and score of corneal fluorescein staining (SCFS). They worsened significantly at 1w post-operation and then gradually improved: OSDI and BUT showed obvious improvement in 1 m post-operation (SMD =  - 0.58, 95%CI = [- 1.04, - 0.13]; SMD = 0.42, 95%CI = [0.06, 0.78]); SCFS was restored to preoperative levels in 3 m after surgery (SMD =  - 0.54, 95%CI = [- 1.16, 0.07]). Another parameter, Schirmer test without anesthesia (SIT), presented transient increase at 1w post-operation (SMD = 0.87, 95%CI = [0.27, 1.47]) and presented a relatively stable improvement after 1 m post-operation (SMD = 0.52, 95%CI = [0.16, 0.89]). All parameters in amniotic membrane graft (AMT) showed better improvement in early stage and they showed non-inferior improvements in the long term compared with conjunctival autograft (CAG). Limbal-conjunctival autograft (LCAG) made excellent improvement to OS in the long term while pterygium excision (PE) showed the worst OS. The type of pterygium (primary and secondary), diabetes mellitus (DM) status, and fixation method had certain effects on the results.

CONCLUSIONS

OS of pterygium is deteriorated at 1w post-operation then gradually improved to preoperative levels after 1 m post-operation. Among various surgery techniques, LCAG had the best improvement to OS which especially displayed in the long-term outcomes.

Study of biomarkers p53, Ki-67, Bcl-2, and VEGF in pterygium

PURPOSE

To study the biomarkers present in primary pterygium samples of patients of Indian ethnicity and compare it with the samples obtained from the unaffected conjunctiva of the same eye.

METHODS

A prospective case-control study of 17 eyes in patients above 10 years of age with primary pterygium who underwent pterygium excision using limbal conjunctival autograft technique. The pterygium samples (cases) and conjunctival samples (controls) were sent for immunohistochemical (IHC) staining for the following biomarkers: p53, Bcl-2, Ki-67, and vascular endothelial growth factor (VEGF).

RESULT

The immunohistochemistry of the samples and the controls revealed p53 positivity in 47.05% of pterygium samples and 29.4% of controls ( P < 0.587). Nine cases each in pterygium and control samples were positive for Ki-67 expression. Differences in the staining pattern between the two groups were not statistically significant ( P < 1.000). Bcl-2 positivity was seen in 10 pterygium samples (58.8%) and 12 controls (70.5%), with no statistical difference between the two groups ( P < 0.455). VEGF expression was seen in both epithelial and endothelial cells of the samples and controls, with no statistical difference between the two groups, with P = 1.000 for the epithelial staining and P = 0.637 for endothelial staining.

CONCLUSION

The expression of biomarkers was comparable in both groups. We conclude that pterygium, against common belief, might not be a localized disease process but a global ocular phenomenon where the apparently healthy tissue also has some ongoing disease process at a molecular level.

Modified sutureless and glue-free method versus conventional sutures for conjunctival autograft fixation in primary pterygium surgery: a systematic review and meta-analysis

BACKGROUND

Pterygium is a common ocular surface disorder that requires surgical intervention for treatment. Conjunctival autografts are preferred over simple excision due to lower recurrence rates. This systematic review and meta-analysis compared the modified sutureless glue-free (MSGF) method with conventional sutures (CS) for conjunctival autograft fixation in primary pterygium surgery.

METHODS

A comprehensive search was conducted in MEDLINE, Embase, CENTRAL, Google Scholar and ClinicalTrials.gov for randomised controlled trials (RCTs) comparing MSGF and CS conjunctival autografts. Outcome measures included operation time, recurrence and postoperative complications. Standardised mean difference (SMD) and risk ratio (RR) were used for continuous and dichotomous outcomes, respectively.

RESULTS

11 RCTs involving 833 participants were included. The analysis revealed that MSGF had a significantly shorter operation time compared with CS (SMD -3.704, 95% CI -5.122 to -2.287, p<0.001). CS was associated with a higher risk of foreign body sensation (RR 0.22, 95% CI 0.06 to 0.74, p=0.01). MSGF was associated with a higher risk of graft dehiscence (RR 9.01, 95% CI 2.74 to 29.68, p=0.000) and graft retraction (RR 2.37, 95% CI 1.17 to 4.77, p=0.02). No significant differences were found in recurrence, graft haemorrhage, granuloma, Dellen and conjunctival oedema.

CONCLUSION

Using the MSGF technique in conjunctival autograft fixation for pterygium surgery reduces operation time by relying solely on the patient's blood for fixation. However, it increases the risk of graft dehiscence and retraction. However, CS is linked to a higher likelihood of experiencing foreign body sensations. Understanding the learning curve and surgeon familiarity with novel techniques is crucial for optimising patient care and surgical outcomes, while individualised decision-making is necessary considering the advantages and disadvantages of each approach. Further research is warranted to minimise complications and optimise surgical outcomes.

Single-cell RNA sequencing reveals the complex cellular niche of pterygium

PURPOSE

Pterygium is a vision-threatening conjunctival fibrovascular degenerated disease with a high global prevalence up to 12 %, while no absolute pharmacotherapy has been applied in clinics. In virtue of single-cell RNA sequencing (scRNA-seq) technique, our study investigated underlying pathogeneses and potential therapeutic targets of pterygium from the cellular transcriptional level.

METHODS

A total of 45605 cells from pterygium of patients and conjunctiva of normal controls (NC) were conducted with scRNA-seq, and then analyzed via integrated analysis, pathway enrichment, pseudotime trajectory, and cell-cell communications. Besides, immunofluorescence and western blot were performed in vivo and in vitro to verify our findings.

RESULTS

In brief, 9 major cellular types were defined, according to canonical markers. Subsequently, we further determined the subgroups of each major cell lineages. Several newly identified cell sub-clusters could promote pterygium, including immuno-fibroblasts, epithelial mesenchymal transition (EMT)-epithelial cells, and activated vascular endothelial cells (activated-vEndo). Besides, we also probed the enrichment of immune cells in pterygium. Particularly, macrophages, recruited by ACKR1+activated-vEndo, might play an important role in the development of pterygium by promoting angiogenesis, immune suppression, and inflammation.

CONCLUSION

An intricate cellular niche was revealed in pterygium via scRNA-seq analysis and the interactions between macrophages and ACKR1+ activated-vEndo might be the key part in the development of pterygia.

Low Rate of Postoperative Pterygium Recurrence in Patients under Treatment with Low-Dose Oral Doxycycline for Chronic Blepharitis: A First Report

PURPOSE

Low doses of systemic doxycycline (LD-SD) inhibit angiogenesis and the expression of matrix metalloproteases, which are determinants of pterygium progression. This study aimed to compare the recurrence rate and visual outcome of pterygium excision in patients undergoing chronic treatment with LD-SD for chronic refractory blepharitis and LD-SD-naive patients.

METHODS

A retrospective analysis of patients that underwent surgical excision and conjunctival graft apposition was conducted. Patients were divided in a TETRA group (under LD-SD treatment at the moment of surgery) and a control group. The main outcome was the rate of recurrence at 1 year postoperatively. Secondary outcomes were the comparisons of surface regularity, visual quality, and dry-eye symptoms at 6-week, 6-month, and 1-year follow-up in the two groups.

RESULTS

The TETRA group showed a significantly lower rate of 1-year recurrence both in primary (p = 0.034) and recurrent (p < 0.001) pterygia. The best corrected visual acuity (BCVA), astigmatic error, corneal total root mean square (RMS), and ocular surface disease index (OSDI) significantly reduced during the follow-up in both groups. The surface asymmetry index and high-order aberrations (HOAs) significantly reduced only in the TETRA group. The final BCVA was significantly higher, while the OSDI score and total RMS and HOAs were significantly lower in the TETRA group compared to the control.

CONCLUSIONS

Patients under treatment with LD-SD showed a lower rate of recurrence at 1-year follow-up compared to controls. These patients also experienced higher BCVA and surface regularity and less dry-eye symptoms.

Potential applications of artificial intelligence in image analysis in cornea diseases: a review

Artificial intelligence (AI) is an emerging field which could make an intelligent healthcare model a reality and has been garnering traction in the field of medicine, with promising results. There have been recent developments in machine learning and/or deep learning algorithms for applications in ophthalmology-primarily for diabetic retinopathy, and age-related macular degeneration. However, AI research in the field of cornea diseases is relatively new. Algorithms have been described to assist clinicians in diagnosis or detection of cornea conditions such as keratoconus, infectious keratitis and dry eye disease. AI may also be used for segmentation and analysis of cornea imaging or tomography as an adjunctive tool. Despite the potential advantages that these new technologies offer, there are challenges that need to be addressed before they can be integrated into clinical practice. In this review, we aim to summarize current literature and provide an update regarding recent advances in AI technologies pertaining to corneal diseases, and its potential future application, in particular pertaining to image analysis.

Accurate detection and grading of pterygium through smartphone by a fusion training model

BACKGROUND/AIMS

To improve the accuracy of pterygium screening and detection through smartphones, we established a fusion training model by blending a large number of slit-lamp image data with a small proportion of smartphone data.

METHOD

Two datasets were used, a slit-lamp image dataset containing 20 987 images and a smartphone-based image dataset containing 1094 images. The RFRC (Faster RCNN based on ResNet101) model for the detection model. The SRU-Net (U-Net based on SE-ResNeXt50) for the segmentation models. The open-cv algorithm measured the width, length and area of pterygium in the cornea.

RESULTS

The detection model (trained by slit-lamp images) obtained the mean accuracy of 95.24%. The fusion segmentation model (trained by smartphone and slit-lamp images) achieved a microaverage F1 score of 0.8981, sensitivity of 0.8709, specificity of 0.9668 and area under the curve (AUC) of 0.9295. Compared with the same group of patients' smartphone and slit-lamp images, the fusion model performance in smartphone-based images (F1 score of 0.9313, sensitivity of 0.9360, specificity of 0.9613, AUC of 0.9426, accuracy of 92.38%) is close to the model (trained by slit-lamp images) in slit-lamp images (F1 score of 0.9448, sensitivity of 0.9165, specificity of 0.9689, AUC of 0.9569 and accuracy of 94.29%).

CONCLUSION

Our fusion model method got high pterygium detection and grading accuracy in insufficient smartphone data, and its performance is comparable to experienced ophthalmologists and works well in different smartphone brands.

Evaluation of lymphotoxin-alpha in pterygium and diagnostic value in active and inactive pterygium states

To explore the correlation between tear LT-a, pterygium status, and dry eye indicators. We established a diagnostic model to evaluate active pterygium. A retrospective study was conducted between June 2021 and June 2023 on 172 patients, comprising 108 men and 64 women. The study analyzed LT-a and various ocular parameters in all participants. The data was collected using Excel software and analyzed using SPSS 25.0 statistical software and Medcalc. We made a nomogram diagnostic model to different diagnosed the state of pterygium. This study found that pterygium has progressive eye surface damage during the active state. There was no significant difference in dry eye indicators between the two groups. However, the concentration of LT-a in the active group was significantly lower than that in the inactive group (P < 0.001). We observed that increased pterygium grade corresponded to a worse ocular surface condition. In addition, LT-a was significantly positively correlated with disease duration, but negatively correlated with age, pterygium size, active pterygium state, and LLT value. The optimal intercept value for evaluating active pterygium in Lt-a was ≤ 0.49 dg/ml. We screened three variables for evaluating active pterygium through Single and Multiple regression analysis: LT-a grading, pterygium size, and congestion score. Finally, we made a reliable diagnostic nomogram model. Pterygium development triggers immune inflammation. Our model based on LT-a identifies active pterygium for personalized treatment options and new research directions.

The efficacy and safety of continuous blanket suture for severe recurrent pterygium with symblepharon

Background

Managing recurrent pterygium combined with symblepharon presents significant challenges in ophthalmology. Clinicians aim to reconstruct the ocular surface, alleviate eye movement restrictions, and minimize recurrence risks.

Objective

Evaluation of efficacy and safety of continuous blanket sutures (CBS) for fixation of large autologous conjunctival grafts in patients with severe recurrent pterygium with symblepharon.

Methods

Retrospective, observational case series. Thirty-nine patients (40 eyes) were included, all with severe recurrent pterygium with symblepharon. During surgery, CBS was employed to affix large autologous conjunctival grafts to the exposed sclera, aiming to restore the ocular surface to smoothness as much as possible. All patients were followed up for more than one year. Main outcome measures include the rate of recurrence, improvement of eye movement, and intraoperative and postoperative complications.

Results

Nearly all patients exhibited a smooth ocular surface and largely restored physiological structures during the follow-up period. There were no graft loss or contraction cases until the last follow-up, with only three eyes experiencing a pterygium recurrence (recurrence rate 7.5%, 3/40). Preoperative eye movement limitations improved significantly from 2.10 ± 0.71 (range 1-3) to 0.33 ± 0.53 (range 0-2; p < 0.001) post-surgery. Other postoperative complications included varying degrees of corneal scarring and a single instance of conjunctival granulomatous hyperplasia (1 eye, 2.5%).

Conclusion

When addressing severe recurrent pterygium with Symblepharon, using CBS to secure large autologous conjunctival grafts during surgery can achieve favorable postoperative outcomes. This surgical method is safe and feasible and effectively rebuilds a smooth ocular surface, improves the appearance of the ocular surface, and reduces the recurrence rate of pterygium after excision.

Genetic evidence implicating circulating lipids and lipid drug targets in pterygium

There is limited knowledge about the impact of circulating lipids and lipid-modifying drugs on pterygium development, with conflicting results reported. Our study aimed to address these questions by applying the Mendelian randomization (MR) approach. A two-step MR model was developed. In the first step, bidirectional two-sample MR was employed to establish the causal relationship between circulating lipids and pterygium risk. In the second step, drug-target MR analysis was conducted to assess the causal effect of proprotein convertase subtilisin/kexin type 9 (PCSK9) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) inhibitors on pterygium outcomes. Genetically predicted low-density lipoprotein cholesterol (LDL-c) levels were found to be significantly associated with an increased risk of pterygium (Inverse variance weighted [IVW] odds ratio [OR] = 2.227; P = 1.53 × 10-4). Similarly, higher total cholesterol (TC) levels exhibited a suggestive association with greater susceptibility to pterygium (IVW OR = 1.806; P = 1.70 × 10-3). Through drug-target MR, a positive causal association was noted between HMGCR-mediated LDL-c levels and pterygium (IVW OR = 6.999; P = 0.016), suggesting that statins may be effective in reducing pterygium risk. The present findings suggest that circulating TC and LDL-c are risk factors for pterygium. Additionally, the results indicate that HMGCR inhibitors, which lower LDL-c levels, have a potential protective effect on pterygium outcomes. Further research is warranted to elucidate the underlying mechanisms involved in pterygium pathogenesis, with a particular focus on cholesterol metabolism.

Are Periocular and Systemic Allergy Conditions Risk Factors for Pterygium?

PURPOSE

To evaluate risk factors for pterygium and prevalence of periocular and systemic diseases among patients with pterygium.

METHODS

A retrospective case-control study was conducted among members of Clalit Health Services (CHS) in Israel, from 2001 to 2022. A total of 13,944 patients diagnosed with pterygium were included. For each case, three controls were matched among all CHS patients according to year of birth, sex, and ethnicity. Mixed models were used to assess differences in demographic characteristics, ocular and systemic diseases between the groups. Generalized estimating equation (GEE) logistic regression was used to estimate the odds ratios (OR) and adjust for confounders.

RESULTS

The average age of pterygium patients was 49 ± 17 years; 51% were male. The results showed significant associations between pterygium and risk factors of vernal kerato-conjunctivitis (OR 2.52, 95% confidence interval [CI]: [1.96-3.24]), chronic allergic conjunctivitis (OR 1.98, 95% CI: [1.65-2.39]), blepharitis (OR 1.91, 95% CI: [1.78-2.04]), chalazion (OR 1.47, 95% CI: [1.30-1.67]) and unspecified systemic allergy (OR 1.21, 95% CI [1.09-1.34]), after adjusting for rural residency status. Glaucoma (OR 0.74, 95% CI [0.64-0.85]) and smoking (OR 0.70, 95% CI [0.66-0.75]) were protective factors against pterygium.

CONCLUSION

Systemic and periocular inflammatory and allergic diseases are risk factors for pterygium.

A New Approach: Determination of the Safe Surgical Margin in Pterygium Surgery

PURPOSE

In this retrospective study, we aimed to determine the safe surgical limit for excision of pterygium tissue. Therefore, we aimed to prevent excessive or incomplete normal conjunctival tissue excision during surgery in the coming years.

METHODS

Autografted pterygium surgery was performed between January 2015 and April 2016, and the excised pterygium tissue was examined histopathologically. The files of 44 patients, who had not previously undergone any ocular surgery, who did not have an inflammatory disease and who continued to be checked for at least 1 year, were retrospectively examined. The distance (P-DSEM) from the excised pterygium tissue to the surgical excision margin was measured by a pathologist. Postoperative recurrence rates were evaluated according to this value. In this way, the clean surgical margin was determined.

RESULTS

The mean age of the participants was 44.77 ± 12.70, and the mean follow-up time was 55.61 ± 16.38 months. Recurrence developed in 5 out of 44 patients (11.4%). The average recurrence duration was 51 ± 13.87 days. Distance to the average surgical margin was 3.88 ± 0.91 mm. The surgical distances of 5 patients with recurrence were 2, 2.5, 2, 3, and 3 mm, respectively. It was determined that recurrence was less as the distance (P-DSEM) from the tissue to the surgical excision margin increased (p = 0.001).

CONCLUSIONS

We found that the recurrence rate in pterygium surgery was linked to the clean surgical margin. When planning pterygium surgery, we believe that determining the amount of tissue to be excised before surgery will reduce recurrence rates.

The role of HPV in the etiopathogenesis of pterygium and the relationship with recurrence

PURPOSE

The primary aim of this study was to determine the prevalence of HPV in pterygium with polymerase chain reaction (PCR) testing and to investigate the relationship with clinicopathological factors. A secondary aim was to evaluate the relationship between HPV and the recurrence of pterygium.

METHODS

The study included 60 patients. PCR analysis was used to determine the presence of HPV. All the patients were followed up in respect of the development of recurrence. Analyses were performed of patient age, pterygium site, specimen and pterygium size, histopathological findings, HPV status, operation technique and postoperative follow-up findings. In the HPV-positive patients, the relationship between HPV subtypes and other factors was evaluated. To determine the risk factors affecting recurrence rates, multivariate Cox regression analysis was applied subsequent to univariate analysis. In the Cox regression model, HPV status, age, sex, specimen size, size and site of pterygium were included among factors that may affect recurrences rates.

RESULTS

Of the total 60 patients, the HPV-PCR test result could not be analysed in 14 because of an insufficient sample. Of the 46 patients with sufficient material for HPV-PCR analysis, the HPV-PCR result was positive in 15 (32.6%). The HPV subtype most often determined was type 16. No statistically significant relationship was determined between HPV positivity and HPV subtype and age or sex. Recurrence was determined in 10% of all the patients. Of the cases determined with recurrence, 66.7% were HPV positive. According to Kaplan-Meier analysis, the recurrence rates in HPV-positive and HPV-negative patients were 26.7% and 6.5%, respectively. A statistically significant difference was found between two groups in terms of recurrence rates (p: 0.046). According to the results of multivariate Cox regression analysis, though not statistically significant, the risk of recurrence was increased 6.18 times in HPV-positive patients with pterygium compared to HPV-negative ones.

CONCLUSION

HPV infection may have a role in the development of pterygium and recurrence, but may not be sufficient alone. HPV probably has a role in the development of pterygium by acting together with several co-factors in the multi-stage process.

Surgical Time and Postoperative Symptoms Study in Pterygium Excision and Amniotic Membrane Graft Using Celularity Triple Layer Dehydrated Amniotic Membrane

Purpose

To evaluate a novel sutureless glueless technique using a triple-layer dehydrated amniotic membrane (TLDAM) for pterygia excisions in surgical time, postoperative pain, epiphora, irritation, and FBS.

Methods

Twenty eyes with pterygia underwent excision with mitomycin C. The conjunctival defect was closed with TLDAM placed on the dried scleral bed with the edges of the amniotic membrane tucked under the edges of the conjunctival defect. Surgical times were measured from injection of lidocaine to final placement of bandage contact lens. After a bandage contact lens was placed, the eye was patched until POD1. Patients graded self-administered questionnaires to rate pain, FBS, irritation, and epiphora on a scale of 1-5 (1-none; 5-severe) at POD1 and POW1.

Results

Surgical times ranged from 6:55 to 12:00, with mean of 8:29. Compared with a previous study of sutureless glueless methodology, the difference in mean surgical time was 11.9 (p < 0.0001). Mean questionnaire scores were as follows: POD1 pain 1.8, FBS 2.3, irritation 1.0, and epiphora 2.6; POW1 pain 1.5, FBS 1.6, irritation 1.6, and epiphora 1.6. Compared to previous studies, this technique showed significantly improved pain at POD1 (p=0.0086, p<0.0001, p<0.0001, p<0.0001) and POW1 (p=0.0002, p=0.0016, p<0.0001). Significant improvement in irritation and FBS was noted at POD1 and POW1. See Table 1 for full analysis.

Conclusion

The sutureless glueless technique using TLDAM is a safe and effective technique compared to current standard methods. There appears to be a significant benefit regarding surgical time and postoperative pain, irritation, epiphora, and FBS compared to previous studies.

TFOS Lifestyle Report: Impact of environmental conditions on the ocular surface

Environmental risk factors that have an impact on the ocular surface were reviewed and associations with age and sex, race/ethnicity, geographical area, seasonality, prevalence and possible interactions between risk factors are reviewed. Environmental factors can be (a) climate-related: temperature, humidity, wind speed, altitude, dew point, ultraviolet light, and allergen or (b) outdoor and indoor pollution: gases, particulate matter, and other sources of airborne pollutants. Temperature affects ocular surface homeostasis directly and indirectly, precipitating ocular surface diseases and/or symptoms, including trachoma. Humidity is negatively associated with dry eye disease. There is little data on wind speed and dewpoint. High altitude and ultraviolet light exposure are associated with pterygium, ocular surface degenerations and neoplastic disease. Pollution is associated with dry eye disease and conjunctivitis. Primary Sjögren syndrome is associated with exposure to chemical solvents. Living within a potential zone of active volcanic eruption is associated with eye irritation. Indoor pollution, "sick" building or house can also be associated with eye irritation. Most ocular surface conditions are multifactorial, and several environmental factors may contribute to specific diseases. A systematic review was conducted to answer the following research question: "What are the associations between outdoor environment pollution and signs or symptoms of dry eye disease in humans?" Dry eye disease is associated with air pollution (from NO2) and soil pollution (from chromium), but not from air pollution from CO or PM10. Future research should adequately account for confounders, follow up over time, and report results separately for ocular surface findings, including signs and symptoms.

The influence of pterygium on corneal densitometry evaluated using the Oculus Pentacam system

Purpose

To assess the effect of pterygium on corneal densitometry (CD) values.

Methods

One hundred and nine patients (155 eyes) with primary pterygium were divided into a severe pterygium group (79 eyes) and a mild-to-moderate pterygium group (76 eyes) according to pterygium severity. Among them, 63 patients had monocular pterygium; and 25 patients (38 eyes) underwent pterygium excision combined with conjunctival autograft follow-up. A Pentacam anterior segment analyzer was used to obtain the CD values and corneal morphological parameters, including central corneal thickness (CCT), flat-axis keratometry (K1), steep-axis keratometry (K2), corneal astigmatism, irregular astigmatism, and spherical aberration. CD was subdivided into four concentric radial regions based on corneal diameter and three layers according to depth.

Results

CD values at 0-12 mm of the anterior 120 μm layer, 0-10 mm of the center layer and full thickness, and 2-6 mm of the posterior 60 μm layer were significantly higher in eyes affected by pterygium than in the contralateral unaffected eyes (all P < 0.05). CD values were significantly higher in the severe pterygium group than in the mild to moderate pterygium group (all P < 0.05). Corneal astigmatism, irregular astigmatism, K1, K2, CCT, and spherical aberration correlated with CD values in eyes with pterygium (all P < 0.05). CD values at 6-10, 0-12 mm in the anterior 120 μm layer and full thickness, 10-12 and 0-12 mm in the center layer were significantly decreased 1 month after pterygium surgery compared with those before surgery (all P < 0.05).

Conclusion

Patients with pterygium had increased CD values, particularly in the anterior and central layers. CD values were correlated with pterygium severity grading and corneal parameters. Pterygium surgery partially reduced the CD values.

The effects of exposure to solar radiation on human health

This assessment by the Environmental Effects Assessment Panel (EEAP) of the Montreal Protocol under the United Nations Environment Programme (UNEP) evaluates the effects of ultraviolet (UV) radiation on human health within the context of the Montreal Protocol and its Amendments. We assess work published since our last comprehensive assessment in 2018. Over the last four years gains have been made in knowledge of the links between sun exposure and health outcomes, mechanisms, and estimates of disease burden, including economic impacts. Of particular note, there is new information about the way in which exposure to UV radiation modulates the immune system, causing both harms and benefits for health. The burden of skin cancer remains high, with many lives lost to melanoma and many more people treated for keratinocyte cancer, but it has been estimated that the Montreal Protocol will prevent 11 million cases of melanoma and 432 million cases of keratinocyte cancer that would otherwise have occurred in the United States in people born between 1890 and 2100. While the incidence of skin cancer continues to rise, rates have stabilised in younger populations in some countries. Mortality has also plateaued, partly due to the use of systemic therapies for advanced disease. However, these therapies are very expensive, contributing to the extremely high economic burden of skin cancer, and emphasising the importance and comparative cost-effectiveness of prevention. Photodermatoses, inflammatory skin conditions induced by exposure to UV radiation, can have a marked detrimental impact on the quality of life of sufferers. More information is emerging about their potential link with commonly used drugs, particularly anti-hypertensives. The eyes are also harmed by over-exposure to UV radiation. The incidence of cataract and pterygium is continuing to rise, and there is now evidence of a link between intraocular melanoma and sun exposure. It has been estimated that the Montreal Protocol will prevent 63 million cases of cataract that would otherwise have occurred in the United States in people born between 1890 and 2100. Despite the clearly established harms, exposure to UV radiation also has benefits for human health. While the best recognised benefit is production of vitamin D, beneficial effects mediated by factors other than vitamin D are emerging. For both sun exposure and vitamin D, there is increasingly convincing evidence of a positive role in diseases related to immune function, including both autoimmune diseases and infection. With its influence on the intensity of UV radiation and global warming, the Montreal Protocol has, and will have, both direct and indirect effects on human health, potentially changing the balance of the risks and benefits of spending time outdoors.

Use of Cryopreserved Amniotic Membrane During Pterygium Excision: Health Economic Analysis

Purpose

To determine the health economic opportunity cost or gain associated with performing pterygium excision surgery using the TissueTuck technique with cryopreserved amniotic membrane (AM) instead of conjunctival autograft (CAU).

Methods

We performed a literature review to determine the average surgical duration of pterygium surgery using CAU with fibrin glue or sutures to calculate the average time saved with the TissueTuck technique. Such time savings was then used to determine the opportunity revenue gain per national average Medicare reimbursement if adjusted to the average surgical duration of cataract surgery.

Results

The time savings achieved using the TissueTuck technique over CAU with fibrin glue is 8.9 min per procedure, which can be applied to additional MSICS or phacoemulsification procedures to generate an opportunity revenue gain of $1167 or $762 per 2022 National Average Medicare reimbursement, respectively. After subtracting the current list cost of AmnioGraft (ie, $645), the opportunity gain is $522 or $117 if the time saving is applied to the above procedures, respectively. Alternatively, the time savings achieved by using the TissueTuck technique over CAU with sutures is 23.4 min per procedure, which can be applied to additional MSICS or phacoemulsification procedures to generate an opportunity revenue gain of $3068 and $2004 per TissueTuck procedure or $2423 or $1359 when accounting for the list cost of AmnioGraft, respectively.

Conclusion

The TissueTuck surgical technique using cryopreserved AM for pterygium takes less time, has lower recurrence rates, and provides an opportunity gain compared to pterygium excision with CAU.

TFOS lifestyle: Impact of societal challenges on the ocular surface

Societal factors associated with ocular surface diseases were mapped using a framework to characterize the relationship between the individual, their health and environment. The impact of the COVID-19 pandemic and mitigating factors on ocular surface diseases were considered in a systematic review. Age and sex effects were generally well-characterized for inflammatory, infectious, autoimmune and trauma-related conditions. Sex and gender, through biological, socio-economic, and cultural factors impact the prevalence and severity of disease, access to, and use of, care. Genetic factors, race, smoking and co-morbidities are generally well characterized, with interdependencies with geographical, employment and socioeconomic factors. Living and working conditions include employment, education, water and sanitation, poverty and socioeconomic class. Employment type and hobbies are associated with eye trauma and burns. Regional, global socio-economic, cultural and environmental conditions, include remoteness, geography, seasonality, availability of and access to services. Violence associated with war, acid attacks and domestic violence are associated with traumatic injuries. The impacts of conflict, pandemic and climate are exacerbated by decreased food security, access to health services and workers. Digital technology can impact diseases through physical and mental health effects and access to health information and services. The COVID-19 pandemic and related mitigating strategies are mostly associated with an increased risk of developing new or worsening existing ocular surface diseases. Societal factors impact the type and severity of ocular surface diseases, although there is considerable interdependence between factors. The overlay of the digital environment, natural disasters, conflict and the pandemic have modified access to services in some regions.

Conjunctival and Limbal Conjunctival Autograft vs. Amniotic Membrane Graft in Primary Pterygium Surgery: A 30-Year Comprehensive Review

INTRODUCTION

The purpose of this study is to compare the "real-life" effectiveness of amniotic membrane graft (AMG) and conjunctival (CAT) or limbal conjunctival (LCA) autograft in the management of primary pterygium.

METHODS

Human-based studies on primary pterygium surgery that were published between 1993 and 2022 with at least 3 months of follow-up were identified, and only those that were retrospective were included. The global recurrence rate of pterygium was assessed for each surgical technique separately. Specific recurrence rates taking into consideration the fixation technique (glue versus sutures) were also measured.

RESULTS

35 real-life retrospective subgroups comprising a total of 3747 eyes were included in the final review. The mean global recurrence rates for CAT, LCA and AMG were 7.61%, 5.50% and 9.0%, respectively. Recurrences were less common for patients who received fibrin glue (5.92%, 2.56% and 3.60%) than for those who received sutures (8.99%, 6.03% and 23.0%) for the three groups, respectively. Surgical techniques combining CAT or LCA with AMG yielded an even lower global recurrence rate (1.83%).

CONCLUSION

AMG seems like a reasonable option that could be considered in primary pterygium surgery, especially when glued to the underlying sclera. Combining AMG with other treatment modalities such as CAT or LCA seems to offer an interesting alternative in terms of recurrence.

Impact of pterygium on central corneal thickness measured by optical coherence tomography in older adults

PURPOSE

To measure the central corneal thickness (CCT) using anterior segment optical coherence tomography (AS-OCT) in older adults with and without pterygium from the Brazilian Amazon Region Eye Survey (BARES).

METHODS

BARES is a population-based epidemiological cross-sectional study conducted in Parintins city. Participants were residents ≥45 years of age identified through a door-to-door interview. Eligible participants were invited for a comprehensive eye exam. Pterygium occurrence and severity were assessed by ophthalmologists through slit-lamp examination considering its location (nasal or/and temporal) and severity (lesion with extension <3 mm, ≥3 mm not reaching the pupillary margin or ≥3 mm reaching the pupillary margin). CCTs were obtained and measurements from the more severely affected eye were included. Images were analyzed offline by masked observers.

RESULTS

A total of 671 subjects, 533 (79.4%) with pterygium in at least one eye and 138 (20.6%) without pterygium in either eye, were examined. The mean CCT evaluated by multiple linear regression and adjusted for demographic variables and pterygium severity was 521 ± 34 μm (median = 521; range = 304-665). Decreased CCT was significantly associated with age and pterygium severity. Individuals aged 65-74 years had CCT 7 μm thinner than those aged 45-54 years (p = 0.044), individuals aged 75 years and older had CCT 15 μm thinner than those aged 45-54 years (p = 0.001), and eyes with severe pterygium had CCT 33 μm thinner than eyes without pterygium (p < 0.001).

CONCLUSIONS

The CCT analysis in this population-based sample shows that a thinner cornea is associated with pterygium severity and older age.

Cryopreserved Amniotic Membrane Using the TissueTuck Technique: A Sutureless Approach for Pterygium Surgery

PURPOSE

The purpose of this study was to evaluate the clinical outcomes of the TissueTuck technique in the management of pterygium.

METHODS

This was a single-center, retrospective review of patients with primary or recurrent pterygium that underwent surgical excision followed by application of cryopreserved amniotic membrane (AM) using the TissueTuck technique. All patients underwent surgery between January 2012 and May 2019. Patient profile, surgical time, complications, and rates of pterygium recurrence were analyzed.

RESULTS

A total of 582 eyes of 453 patients (328 female patients; 65.1 ± 13.9 years) were included for analysis and initially presented with primary (92%) pterygium. The average duration of pterygium excision surgery was 14.7 ± 5.2 minutes (median: 14, range: 4-39 minutes) with mitomycin C administration in 257 (45%) eyes. At the last follow-up of 30.2 ± 22.2 months (median: 24.5, range: 3-94 months), BCVA significantly improved from logMAR 0.23 at baseline to logMAR 0.19 ( P < 0.0001). Recurrence rate was 2.3% but only 0.7% (2/274) in those cases with primary, single-headed pterygium without mitomycin C treatment. Other postoperative complications in that cohort included granuloma (7.9%), scarring (3.8%), and diplopia in extreme lateral gaze (2.5%). The AM remained secured to the ocular surface throughout the postoperative period.

CONCLUSIONS

The TissueTuck surgical technique with cryopreserved AM can be performed in minimal time and result in a low recurrence and complication rate after pterygium surgery.

Prevalence and associated factors for pterygium in a Chinese rural population with type 2 diabetes in a cross-sectional study: Jiangsu Diabetic Eye Disease Study (JDEDS)

PURPOSE

To investigate the pterygium prevalence and evaluate risk factors of pterygium in rural type 2 diabetic (D2M) patients aged 50 years and above in Funing Country, Jiangsu Province, China.

METHODS

A cross-sectional ophthalmic survey was conducted in type 2 diabetes mellitus (D2M) patients aged ≥ 50 years in Funing County, Jiangsu Province, China, which was named Jiangsu Diabetic Eye Disease Study (JDEDS). All participants underwent a comprehensive questionnaire and ocular examination. Pterygium was diagnosed by slit lamp examination. The risk factors associated with pterygium were evaluated with logistic regression models.

RESULTS

The prevalence of pterygium was 22.37% (n = 427) and 95% confidence interval (CI) (20.50-24.24%) in D2M patients aged 50 years and above in JDEDS. The prevalence of pterygium was 18.32% (95% CI 15.33-21.32%) in men and 24.43% (95% CI 22.06-26.80%) in women. Women had a higher prevalence than men (p = 0.001). Multivariate analysis showed, for male participants with D2M, pterygium was independently associated with increasing age [70-79 years: OR and 95% CI 2.49(1.20-5.18), p = 0.014; ≥ 80 years: 4.84(2.04-11.47), p < 0.001], while cigarette smoking was the protective factors, especially in current smoker [OR and 95% CI 0.79(0.67-0.92); p = 0.003]. For female participants with D2M, age [60-69 years OR and 95% CI 1.68(1.07-2.62), p = 0.023; 70-79 years: 2.62(1.69-4.06), p < 0.001; ≥ 80 years:3.24(1.70-5.90), p < 0.001], hypertension [OR and 95% CI 1.40(1.05-1.87), p = 0.024], BMI 24-27.9 [OR and 95% CI 1.20(1.00-1.44), p = 0.047], higher HbA1c [(5.6-7.9) % OR and 95% CI 1.42(1.10-1.82), p = 0.006; (8.0-9.9) %: 1.32(1.10-1.58), p = 0.003] were risk factors.

CONCLUSIONS

D2M patients aged over 50 years has a high prevalence of pterygium in JDEDS. The pterygium prevalence is higher in female D2M participants. Diabetes and related factors may be risk factors of pterygium in female D2M patients. Further studies are needed to explore the gender difference in the pathogenesis of pterygium in D2M subjects.

[Correction of refractive disorders after surgical treatment of recurrent pterygium (case study)]

Lamellar keratoplasty is the most effective and safe method of surgical treatment of recurrent pterygium, providing restoration of the corneal frame and optical properties and a high anti-relapse effect due to the barrier properties of the lamellar graft. However, potential postoperative changes in the regularity of the anterior and posterior surfaces of the cornea (especially in case of advanced stage of fibrovascular tissue growth) do not always allow achieving high functional results of treatment. The article presents a clinical case that demonstrates the effectiveness and safety of excimer laser correction of refractive disorders after surgical treatment of pterygium.

Advances in artificial intelligence applications for ocular surface diseases diagnosis

In recent years, with the rapid development of computer technology, continual optimization of various learning algorithms and architectures, and establishment of numerous large databases, artificial intelligence (AI) has been unprecedentedly developed and applied in the field of ophthalmology. In the past, ophthalmological AI research mainly focused on posterior segment diseases, such as diabetic retinopathy, retinopathy of prematurity, age-related macular degeneration, retinal vein occlusion, and glaucoma optic neuropathy. Meanwhile, an increasing number of studies have employed AI to diagnose ocular surface diseases. In this review, we summarize the research progress of AI in the diagnosis of several ocular surface diseases, namely keratitis, keratoconus, dry eye, and pterygium. We discuss the limitations and challenges of AI in the diagnosis of ocular surface diseases, as well as prospects for the future.

Deep learning algorithms for automatic detection of pterygium using anterior segment photographs from slit-lamp and hand-held cameras

BACKGROUND/AIMS

To evaluate the performances of deep learning (DL) algorithms for detection of presence and extent pterygium, based on colour anterior segment photographs (ASPs) taken from slit-lamp and hand-held cameras.

METHODS

Referable pterygium was defined as having extension towards the cornea from the limbus of >2.50 mm or base width at the limbus of >5.00 mm. 2503 images from the Singapore Epidemiology of Eye Diseases (SEED) study were used as the development set. Algorithms were validated on an internal set from the SEED cohort (629 images (55.3% pterygium, 8.4% referable pterygium)), and tested on two external clinic-based sets (set 1 with 2610 images (2.8% pterygium, 0.7% referable pterygium, from slit-lamp ASP); and set 2 with 3701 images, 2.5% pterygium, 0.9% referable pterygium, from hand-held ASP).

RESULTS

The algorithm's area under the receiver operating characteristic curve (AUROC) for detection of any pterygium was 99.5%(sensitivity=98.6%; specificity=99.0%) in internal test set, 99.1% (sensitivity=95.9%, specificity=98.5%) in external test set 1 and 99.7% (sensitivity=100.0%; specificity=88.3%) in external test set 2. For referable pterygium, the algorithm's AUROC was 98.5% (sensitivity=94.0%; specificity=95.3%) in internal test set, 99.7% (sensitivity=87.2%; specificity=99.4%) in external set 1 and 99.0% (sensitivity=94.3%; specificity=98.0%) in external set 2.

CONCLUSION

DL algorithms based on ASPs can detect presence of and referable-level pterygium with optimal sensitivity and specificity. These algorithms, particularly if used with a handheld camera, may potentially be used as a simple screening tool for detection of referable pterygium. Further validation in community setting is warranted.

SYNOPSIS/PRECIS

DL algorithms based on ASPs can detect presence of and referable-level pterygium optimally, and may be used as a simple screening tool for the detection of referable pterygium in community screenings.

Preoperative Intralesional Bevacizumab Injection in Primary Pterygium in Tunisian Patients: A Randomized Controlled Prospective Study

Purpose

To assess the efficacy and safety of a single preoperative intralesional bevacizumab injection as an adjuvant treatment before primary pterygium surgery.

Methods

We conducted a randomized controlled interventional study from January 2019 to December 2020. The study included a total of 60 patients (60 eyes) with primary pterygium. We defined two groups of 30 patients each. Group A received an intralesional injection of bevacizumab (Avastin), 1 month before surgery (lesion excision and conjunctival autograft). Group B (control) had only the surgical treatment. Patients were followed up 7 days (D7), 1 month (M1), 3 months (M3), and 6 months (M6) postoperatively. Pre-, per-, and postoperatively, photographs of the lesions were taken, as well as a histopathological examination. The main outcome measures were the change in functional discomfort following intralesional bevacizumab injection and pterygium recurrence. Recurrence was defined as fibrovascular tissue growth invading the cornea. Therapeutic success was defined as the absence of pterygium recurrence in M6.

Results

The mean age of the 60 patients was 54.17 ± 10.53. After bevacizumab injection, the preoperative functional discomfort score decreased significantly (P = 0.048). There was a significant improvement in grade and color intensity (P = 0.001). We noted no local nor systemic complications after intralesional injection of bevacizumab. After pterygium excision, the success rate was statistically higher in Group A (P = 0.047). There was no significant difference in either final best-corrected spectral visual acuity or astigmatism between the two groups. We noted a statistically significant association between recurrence and color intensity (P = 0.046), vascular density (P = 0.049), and the degree of elastic tissue degeneration (P = 0.040).

Conclusion

A single preoperative subconjunctival injection of bevacizumab 1 month before surgery decreases the vascularity of newly formed blood vessels and hence may reduce the recurrence rate.

Amniotic membrane transplantation and conjunctival autograft combined with mitomycin C for the management of primary pterygium: A systematic review and meta-analysis

Background

Pterygium is a common ocular surface disease. Recurrence is the greatest concern in the treatment of pterygium. Thus, a standardized and effective treatment modality with minimal risk for complications is needed for the management of pterygium. The aim of this systematic review and meta-analysis was to evaluate different tissue grafting options, including conjunctival autograft (CAG) with mitomycin C (MMC), CAG alone, and amniotic membrane transplantation (AMT), for the management of primary pterygium.

Methods

We searched the MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases for relevant studies. We included randomized controlled trials (RCTs) in which CAG + MMC and AMT were compared with surgical excision with CAG alone for the treatment of primary pterygium. The rates of recurrence and adverse events reported in the studies were also evaluated. Risk ratio (RR) was used to represent dichotomous outcomes. The data were pooled using the inverse variance weighting method. The quality of the evidence derived from the analysis was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials.

Results

Twelve RCTs (n = 1144) were deemed eligible and included for analysis. Five RCTs had a low risk of bias, five had some concerns, and two had a high risk of bias. Subgroup analysis showed a statistically significant reduction in the rate of pterygium recurrence after CAG + MMC (RR = 0.12; 95% confidence interval [CI], 0.02–0.63). This outcome was rated as high-quality evidence according to the GRADE criteria. There were insignificant differences between the rates of recurrence after AMT and CAG (RR = 1.51; 95% CI, 0.63–3.65). However, this result was rated as low-quality evidence. Regarding adverse events, patients treated using AMT showed significantly lower rates of adverse events than those treated using CAG (RR = 0.46; 95% CI, 0.22–0.95). However, this finding was rated as low-quality evidence as well. CAG + MMC showed a safety profile comparable to that of surgical excision with CAG alone (RR = 1.81; 95% CI, 0.40–8.31). This result was also rated as low-quality evidence.

Conclusion

A single intraoperative topical application of 0.02% MMC during excision of pterygium followed by CAG has significantly shown to decrease the rate of pterygium recurrence to 1.4% with no severe complications.