Surgical Management of Pterygium

Prospective Study: Utility of Anterior Segment Optical Coherence Tomography to Identify Predictive Factors of Recurrence in Pterygium Surgery

Background/Objectives: The main purpose of this study is to determine, by anterior segment optical coherence tomography (AS-OCT), the anatomical characteristics, both preoperatively and postoperatively, that correlate with a higher rate of pterygium recurrence after surgery with exeresis and conjunctival autograft with biological glue. Methods: A total of 50 eyes which were listed for primary pterygium surgery at an ophthalmology tertiary centre were treated with standard pterygium excision and a conjunctival autograft with tissue glue. Ten variables were measured with AS-OCT (Casia 2; Tomey Corp., Nagoya, Japan) during six control visits with all patients. Finally, statistical analysis was performed using SPSS (SPSS stadistics®, IBM®, version 21.0.0.0) for descriptive variables and R-project (The R foundation©, version 3.0.2) for the rest of the analyses, including a descriptive analysis and an inferential analysis studying prognostic factors of recurrence and their predictive capacity. Results: Among the 50 patients who underwent surgery, recurrence was detected in 8 cases (rate 16%; 95% CI: 5.8-26.2%). Most cases (n = 6) were detected 3 months after surgery. The pattern of recurrences was atrophic in two thirds of the cases; none required reintervention. Preoperative total conjunctival thickness at 3 mm was significantly increased in patients who developed recurrence. One week after surgery, epithelial and stromal thickness at 1 mm and total thickness at 3 mm proved to be useful for predicting recurrence. Both models have significant discriminant capacity. Conclusions: By imaging the graft with AS-OCT preoperatively and 7 days after surgery, the risk of future recurrence can be predicted.

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.

The Role of 20% Ethanol in Enhancing Pterygium Surgery Outcomes: A Clinical Study

Introduction Pterygium is an ocular surface disorder characterized by a hyperplastic growth of conjunctiva encroaching over the cornea. It causes redness, watering, and foreign body sensation. Surgical excision is the preferred mode of treatment when there is encroachment over the visual axis, chronic irritation, restricted ocular motility, and cosmetic concerns. Various surgical methods have been adopted for the treatment and to prevent recurrences. This study assessed the effectiveness and safety of 20% ethanol as an adjuvant in pterygium excision with conjunctival autograft implantation, evaluating surgical outcomes. Methods A prospective hospital-based interventional study was conducted among 30 patients with pterygium from August 2022 to December 2023. Patients were evaluated preoperatively for anterior segment, posterior segment, visual acuity, and corneal astigmatism. Pterygium was excised using 20% ethanol as an adjuvant, and conjunctival autograft was placed over the bare sclera without sutures. Patients were evaluated on postoperative days 1, 8, 30, and 90 for graft condition, visual acuity, corneal astigmatism, and associated complications. Results After three months of follow-up, the mean visual acuity improved to LogMAR 0.46±0.35 (p=0.001), which was statistically significant, and the average corneal astigmatism decreased from 3.36±2.87 to 0.87±0.57 (p=0.0001). No recurrence was noted among the participants. Conclusion This study has shown that using 20% ethanol as an adjuvant for pterygium excision facilitated clean dissection of a pterygium from the underlying cornea and the pterygium-induced corneal astigmatism has significantly decreased, which led to progress in vision.

The effect of cyclosporine a in pterygium surgery using fibrin glue

BACKGROUND/OBJECTIVES

To evaluate the effect of topical cyclosporine A (CsA) 0.05% in patients with pterygium surgery using fibrin glue (FG).

SUBJECTS/METHODS

Patients with primary nasal pterygium were retrospectically analyzed and categorized into two groups: Group 1 with 41 eyes from 38 patients as a control group and group 2 with 39 eyes from 36 patients who received topical CsA twice a day for 6 months. Patients were assessed for recurrence rate, tear film parameters, side effects, and complications at postoperative intervals of 1-7 days; 1st, 3rd, 6th and 12th months. The follow-up period was 1 year.

RESULTS

The two groups were age (p = 0.934) and sex (p = 0.996) matched. CsA drop was discontinued in one patient due to burning sensation and conjunctival hyperemia after 1 week. There was no statistically significant difference between the mean preoperative and postoperative 1st year Schirmer I and tear break-up time (TBUT) values in group 1 (p = 0.136; p = 0.069). Although the difference between the mean preoperative and postoperative 1st year TBUT values in group 2 was not statistically different (p = 0.249), Schirmer I results were higher postoperatively (p = 0.003). There was no statistically significant difference between preoperative Schirmer (p = 0.496), postoperative Schirmer (p = 0.661), preoperative TBUT (p = 0.240) and postoperative TBUT (p = 0.238) results of the two groups. Recurrence was observed in only one patient from group 1.

CONCLUSION

No recurrent pterygium cases were observed in group 2. Schirmer I values were higher postoperatively in group 2; thus,topical CsA treatment may improve lacrimal secretion and be effective after pterygium surgery with FG.

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.

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.

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.

[Current possibilities for the diagnosis and treatment of pterygium]

Pterygium is a common inflammatory-proliferative disease characterized by the invasion of degeneratively altered fibrovascular tissue into the cornea. This literature review analyzes the etiological factors and pathogenetic concepts of its development, describes modern methods of diagnostics and surgical treatment of pterygium, and pays particular attention to the assessment of structural and functional changes in the cornea occurring during the growth of pterygium and after its excision.

The role of anterior segment optical coherence tomography in the evaluation of the pterygium

BACKGROUND

To evaluate the ability of anterior segment optical coherence tomography (AS-OCT) to visualize the anatomic features of the pterygium and its invasion of the corneal layers.

METHODS

Seventy-five eyes of 54 patients diagnosed with pterygium were included. All subjects underwent complete ophthalmologic examinations, including AS-OCT. The limbus-apex distance, vertical height at the limbus, invasion of the Bowman's and stromal layers, and other morphologic structures of the pterygium tissue were analyzed.

RESULTS

The mean age of the patients was 49.67 ± 16.49 (20-85) years. The mean apex-limbus distance was 2548.37 ± 1026.32 (933-4597) μm, and the mean vertical height at the limbus was 4843.89 ± 1374.10 (1740-7784) μm. A space was observed beneath the pterygium tissue in 44 (58.67%) eyes. The mean width and height of this space were 1756.33 ± 560.22 (1009-3095) μm and 231.70 ± 85.88 (109-465) μm, respectively. Invasion of the Bowman's layer was apparent in 74 (98.67%) eyes, and invasion of the stromal layer was detected in 33 (44%) eyes. A hyperreflective layer was observed beneath the epithelial layer at the edge of the pterygium apex in 31 (41.33%) eyes. In 24 (92.31%) of the 26 advanced pterygium cases and 20 (40.82%) of the 49 early pterygium cases, a subpterygium space was found beneath the lesion (p = 0.0001).

CONCLUSION

AS-OCT enables measurement of the actual size and thickness of pterygia, assessment of invasion of the Bowman's and stromal layers of the cornea, and evaluation of the pterygium structure. Over half of the eyes exhibited space beneath the pterygium.

Snatching: A modified cosmetic technique in pterygium surgery without using scalpel

AIM

To evaluate the cosmetic surgical outcomes of primary corneal pterygia excision using the avulsion (snatching) technique.

METHODS

A prospective, interventional study included twenty-five eyes of 25 patients with primary pterygium underwent excision were followed up for at least 6 months. In all patients, snatching (modified avulsion) technique was utilised to avulse the pterygium head off the corneal surface and remove any residual fibres by Colibri without need for keratectomy with a scalpel.

RESULTS

The study involved 25 eyes of 25 patients with an average age of 42.5±56.5 years. The mean follow-up was 6 months. One-week post-op, 8 patients (32%) reported they can tell which is the operated eye but looked untouched while 17 (68%) patients reported that the operated eye looked red but is accepted. Twenty patients (80%) reported some discomfort while the remaining 5 patients (20%) reported no discomfort. Cornea examination showed a clear cornea in 18 eyes (72%), 6 eyes (24%) had mild keratitis, and 1 eye (4%) had clouding at the surgical site. Over an average of six months post-op follow-up period, all the patients (100%) reported they cannot tell which eye had the surgery and none (0%) of them reported discomfort. Examination of the cornea was clear in 24 (96%) eyes, but 1 (4%) eye had mild keratitis.

CONCLUSION

Snatching (modified avulsion) technique was found to be effective, safe, and presents decent aesthetic appearance for the management of primary corneal pterygia when safety points are firmly followed.

Ocular-Surface Regeneration Therapies for Eye Disorders: The State of the Art

The ocular surface is a complex structure that includes cornea, conjunctiva, limbus, and tear film, and is critical for maintaining visual function. When the ocular-surface integrity is altered by a disease, conventional therapies usually rely on topical drops or tissue replacement with more invasive procedures, such as corneal transplants. However, in the last years, regeneration therapies have emerged as a promising approach to repair the damaged ocular surface by stimulating cell proliferation and restoring the eye homeostasis and function. This article reviews the different strategies employed in ocular-surface regeneration, including cell-based therapies, growth-factor-based therapies, and tissue-engineering approaches. Dry eye and neurotrophic keratopathy diseases can be treated with nerve-growth factors to stimulate the limbal stem-cell proliferation and the corneal nerve regeneration, whereas conjunctival autograft or amniotic membrane are used in subjects with corneal limbus dysfunction, such as limbal stem-cell deficiency or pterygium. Further, new therapies are available for patients with corneal endothelium diseases to promote the expansion and migration of cells without the need of corneal keratoplasty. Finally, gene therapy is a promising new frontier of regeneration medicine that can modify the gene expression and, potentially, restore the corneal transparency by reducing fibrosis and neovascularization, as well as by stimulating stem-cell proliferation and tissue regeneration.

Efficacy and safety of anti-vascular endothelial growth factor agents in the treatment of primary pterygium

Purpose

To further evaluate the efficacy and safety of anti-vascular endothelial growth factor (VEGF) agents in management of primary pterygium.

Methods

Randomized controlled trials (RCTs) in databases of PubMed, Web of Science, Embase, and the Cochrane Central Register of Controlled Trials were searched from inception to September 2022. Recurrences and complications were evaluated as the pooled risk ratio (RR) and 95% confidence interval (CI) using random-effects model.

Results

In total of 1,096 eyes in 19 RCTs were included. Anti-VEGF agents statistically decreased recurrence rate of pterygium following surgery (RR 0.47, 95% CI 0.31-0.74, P < 0.001). Subgroup analysis showed that anti-VEGF as an adjunct to bare sclera (RR 0.34, 95% CI 0.13-0.90, P = 0.03) and conjunctival autograft (RR 0.50, 95% CI 0.26-0.96, P = 0.04) statistically reduced recurrence rate, while the effect was not favorable for conjunctivo-limbo autograft (RR 0.99, 95% CI 0.36-2.68, P = 0.98). Anti-VEGF agents statistically decreased recurrence in White patients (RR 0.48, 95% CI 0.28-0.83, P = 0.008), while didn't in Yellow patients (RR 0.43, 95% CI 0.12-1.47, P = 0.18). Both topical (RR 0.19, 95% CI 0.08-0.45, P < 0.001) and subconjunctival anti-VEGF agents (RR 0.64, 95% CI 0.45-0.91, P = 0.01) had a positive influence on recurrence. There was no statistically significant difference in complications between the groups (RR 0.80, 95% CI 0.52-1.22, P = 0.29).

Conclusions

As adjuvant treatment, anti-VEGF agents statistically reduced the recurrence following pterygium surgery, especially among White patients. Anti-VEGF agents were well tolerated without increased complications.

Epidemiologic characteristics and the change of surgical methods of pterygium and pseudopterygium from 2013 to 2019 in China: A retrospective analysis

Introduction

Pterygium is a common multifactorial external eye disease, which causes various ocular symptoms and negatively affects appearance. The aim of this study was to analyze the epidemiological characteristics and the change of surgical methods of pterygium and pseudopterygium in China from 2013 to 2019.

Materials and methods

This study was a hospital-based nationwide retrospective study to estimate the epidemiologic characteristics and the change of surgical methods of pterygium and pseudopteygium in China from 2013 to 2019. The data was extracted from the Hospital Quality Monitoring System (HQMS) database. The diagnosis was based on the tenth revision of the International Classification of Diseases (ICD-10) code.

Results

Our study included 1,007,800 pterygium and 2,681 pseudopteygium inpatients. From 2013 to 2019, the proportion of pterygium and pseudopterygium patients who underwent surgery, among all ophthalmology inpatients, increased from 3.3% in 2013 to 7.84% in 2019. The male-female ratio of surgically treated pterygium and pseudopterygium is 1:1.8 and 1.6:1 respectively. Among all age groups, the hospitalized pterygium patients who received surgery were mainly 60-69 years old, accounting for 36.53%. The pseudopterygium patients who received surgery were mostly 50-59 years old, accounting for 24.02%. Among the 31 provinces of mainland China, Yunnan Province has the highest proportion of pterygium patients treated surgically (6.40%), while Shanghai has the highest proportion of pseudopterygium patients treated surgically (12.98%). The most common occupation of participants in the study was farmer, accounting for 47.62% and 28.53%, respectively. During the study period, the application of autologous stem cell transplantation increased year by year, and became the first choice for pterygium and pseudopterygium surgery.

Discussion

This study was the first to describe the epidemiological characteristics and surgical methods of hospitalized pterygium and pseudopterygium patients in China. This study provides important information for better diagnosis, treatment and prevention of pterygium and pseudopterygium.

ZD6474 Attenuates Fibrosis and Inhibits Neovascularization in Human Pterygium by Suppressing AKT-mTOR Signaling Pathway

Purpose: To investigate the antifibrotic effect of ZD6474 in human pterygium fibroblasts (HPFs) and angiogenesis in human umbilical vein endothelial cells (HUVECs) compared with mitomycin C (MMC). Methods: Pterygium and tenon fibroblasts were isolated from patients undergoing surgery to culture HPFs and human tenon fibroblasts (HTFs). The effects of ZD6474 on HPF, HTF, and HUVEC proliferation and migration were detected using CCK8 and wound-healing assays, respectively. Fibrosis and epithelial-mesenchymal transformation (EMT) were evaluated by western blotting [transforming growth factor beta (TGF-β)1/2 and snail] and immunofluorescence (vimentin and α-smooth muscle actin). The antiangiogenic effect of ZD6474 on HUVECs was assessed using a tube formation assay. To determine the potential mechanism, the expression of phosphorylated AKT (p-AKT) and phosphorylated mTOR (p-mTOR) was evaluated by treatment with ZD6474 via western blotting. Results: ZD6474 robustly inhibited the proliferation and migration of HPFs rather than HTFs compared with those in the MMC group (**P < 0.01). In HPFs, fibrosis and EMT (vimentin, TGF-β1/2, and snail) were significantly reversed by ZD6474. MMC (>50 μg/mL) significantly reduced HTF viability, whereas ZD6474 (<5 μM/mL) did not decrease HTF viability. HUVEC proliferation and migration were clearly decreased, and tube formation was notably interrupted by ZD6474. Activation of p-AKT and p-mTOR was inhibited by ZD6474 treatment of HPFs and HUVECs. Conclusion: ZD6474 is more effective than MMC in reducing fibrosis and EMT in HPFs. In addition, ZD6474 was less toxic to HTFs. ZD6474 also exhibited antiangiogenic effects in HUVECs. This study may aid in the development of novel agents to prevent pterygium recurrence after pterygium excision.

Key Genes of Immunity Associated with Pterygium and Primary Sjögren's Syndrome

Pterygium and primary Sjögren's Syndrome (pSS) share many similarities in clinical symptoms and ocular pathophysiological changes, but their etiology is unclear. To identify the potential genes and pathways related to immunity, two published datasets, GSE2513 containing pterygium information and GSE176510 containing pSS information, were selected from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) of pterygium or pSS patients compared with healthy control conjunctiva, and the common DEGs between them were analyzed. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted for common DEGs. The protein-protein interaction (PPI) network was constructed using the STRING database to find the hub genes, which were verified in clinical samples. There were 14 co-upregulated DEGs. The GO and KEGG analyses showed that these common DEGs were enriched in pathways correlated with virus infection, antigen processing and presentation, nuclear factor-kappa B (NF-κB) and Th17 cell differentiation. The hub genes (IL1R1, ICAM1, IRAK1, S100A9, and S100A8) were selected by PPI construction. In the era of the COVID-19 epidemic, the relationship between virus infection, vaccination, and the incidence of pSS and pterygium growth deserves more attention.

Resveratrol inhibits TGF-β1-induced fibrotic effects in human pterygium fibroblasts

BACKGROUND

Resveratrol is a polyphenolic phytoalexin which has the properties of anti-oxidant, anti-inflammatory and anti-fibrotic effects. The aim of this study was to investigate the anti-fibrotic effects of resveratrol in primary human pterygium fibroblasts (HPFs) and elucidate the underlying mechanisms.

METHOD

Profibrotic activation was induced by transforming growth factor-beta1 (TGF-β1). The expression of profibrotic markers, including type 1 collagen (COL1), α-smooth muscle actin (α-SMA), and fibronectin, were detected by western blot and quantitative real-time-PCR after treatment with various concentrations of resveratrol in HPFs to investigate the anti-fibrotic effects. Relative signaling pathways downstream of TGF-β1 were detected by Western blot to assess the underlying mechanism. Cell viability and apoptosis were assessed using CCK-8 assay and flow cytometry to evaluate proliferation and drug-induced cytotoxicity. Cell migration and contractile phenotype were detected through wound healing assay and collagen gel contraction assay.

RESULTS

The expression of α-SMA, FN and COL1 induced by TGF-β1 were suppressed by treatment with resveratrol in dose-dependent manner. The Smad3, mitogen-activated protein kinase (p38 MAPK) and phosphatidylinositol-3-kinase (PI3K) / protein kinase B (AKT) pathways were activated by TGF-β1, while resveratrol attenuated those pathways. Resveratrol also inhibited cellular proliferation, migration and contractile phenotype, and induced apoptosis in HPFs.

CONCLUSIONS

Resveratrol inhibit TGF-β1-induced myofibroblast activation and extra cellular matrix synthesis in HPFs, at least partly, by regulating the TGF-β/Smad3, p38 MAPK and PI3K/AKT pathways.

Fibroblast Growth Factor-2 (FGF-2) Expression in Pterygia Using Cell Spot Arrays

Fibroblast growth factor (FGF) is a main regulator of cell differentiation, cell migration and angiogenesis in normal and abnormal conjunctiva epithelia, but specific mechanisms of its aberrant expression are yet to be investigated. In the present study, we investigated FGF-2 protein expression within several pterygia. Using a liquid-based cytology assay, we obtained cell specimens from pterygia and healthy tissues directly from patients. A combination of immunocytochemistry followed by digital image analysis showed significant overexpression of FGF-2 in all the examined pterygia. In 30/60 (50%) cases there were high levels of staining intensity, whereas in the remaining 30/60 (50%) cases there were moderate levels of expression. FGF-2 levels of the control group were significantly lower in comparison with the pterygia group. There was no significant correlation between FGF-2 levels and either sex or location of the pterygium. FGF-2 levels had a significant correlation with morphological characteristics of the pterygia. More specifically, FGF-2 levels were significantly higher in the pterygia with a fleshy morphology. Interestingly, recurrent lesions demonstrated high expression levels. An overexpression of FGF-2 has been observed frequently in pterygia, where it may play a crucial role in determining the lesion’s progression. FGF-2 upregulation correlates with the morphology of pterygia and its tendency to recur. Cell spot analysis based on liquid-based cytology is a simple, yet effective, method for detecting a broad spectrum of protein markers and could be useful in analyzing potential pterygia patient samples.

Evaluating the Efficacy and Safety of Different Pterygium Surgeries: A Review of the Literature

The search for the "gold standard" in the surgical treatment of pterygium has been ongoing for over two decades. Despite the development of various surgical techniques, recurrence rates range from 6.7% to 88% depending on the method used. This review discusses the latest and most commonly used methods for the surgical removal of pterygium, primarily focusing on efficacy and safety. Moreover, this review includes articles that either evaluated or compared surgical methods and clinical trials for primary and recurrent pterygium. Limited data are available on combined methods as well as on the efficacy of adjuvant treatment. The use of adjuvant intraoperative mitomycin C (MMC) and conjunctival autografting (CAU) are the two most highly recommended options, as they have the lowest rates of postoperative recurrence.

A Randomized Controlled Trial to Manage Postoperative Ocular Pain after Pterygium Excision with Conjunctival Autograft Transplantation with a Single Application of 2% Sodium Hyaluronate

Purpose

To assess the effectiveness of a single application of 2% sodium hyaluronate (SH) in controlling pain after pterygium excision as compared with that of a control group.

Methods

We performed a prospective randomized controlled trial in the patients who underwent pterygium excision. The outcome of topical application of 2.0% SH was measured using the visual analogue scale (VAS), in comparison with that observed in a control group (without SH). The area of ocular surface defects was assessed by ImageJ freeware. Analysis of pain scores and ocular surface defects were observed from both groups immediately after the operation, Day 0, and 3 subsequent days.

Results

Thirty patients were randomly divided into control group and SH treatment group. The initial area of the ocular surface defect on Day 0 was approximately the same for both groups (p=0.242). The medians of pain score assessed by the VAS on Days 0, 1, and 2 were 5, 3, and 0 for the SH group and 6, 5, and 3 for the control group, respectively. The pain score was statistically significantly decreased in the SH group compared to the control group on Day 1 (p < 0.001) and Day 2 (p < 0.001). The pain level of both groups was nearly the same on Day 3 (p=0.141). The area of ocular surface defects was significantly different between two groups on Day 1 (p < 0.001) and Day 2 (p < 0.001). Postoperative complications were not observed.

Conclusion

A single topical application of 2% SH in pterygium excision was effective in relieving pain in the early postoperative period without any adverse effects. This innovation may provide alternative pain control in pterygium surgery.

Acupoint Massage plus Recombinant Bovine Basic Fibroblast Growth Factor Ophthalmic Gel and Limbal Stem Cell Transplantation on Visual Quality, Corneal Refraction, and Aesthetic Outcome in Patients with Pterygium

Objective

To investigate the clinical study of acupoint massage combined with recombinant bovine basic fibroblast growth factor (rbFGF) ophthalmic gel combined with limbal stem cell transplantation on visual quality, corneal refraction, and aesthetic outcome in patients with pterygium.

Methods

Sixty patients with pterygium treated in People's Hospital of Lujiang County from March 2018 to May 2021 were randomized into the control group and the research group by the random number table method, with 30 cases in each group. The control group received rbFGF plus limbal stem cell transplantation. The research group was treated with acupoint massage additionally.

Results

The total clinical effective rate in the study group was higher than that in the control group (P < 0.05); after treatment, the modulation transfer function (MTF) cutoff and Strehl ratio (SR) levels in the study group were significantly higher than those in the control group, and the tear film-related objective scatter index (TF-OSI) was significantly lower than that in the control group (P < 0.05); corneal horizontal curvature and corneal vertical curvature in the study group after treatment were significantly higher than those in the control group, and corneal astigmatism degree (CAD) levels were significantly lower than those in the control group (P < 0.05); the levels of the break-up time (BUT) and Schirmer test (SIT) in the study group were significantly higher after treatment, compared with the control group (P < 0.05); and the incidence of adverse manifestations in the study group was significantly lower than that in the control group (P < 0.05).

Conclusion

Acupoint massage combined with rbFGF ophthalmic gel combined with limbal stem cell transplantation is effective in clinical treatment of pterygium.

Autologous simple conjunctival epithelial transplantation for primary pterygium

PURPOSE

To evaluate the feasibility of a new method of conjunctival transplantation to achieve recovery of the normal conjunctival epithelium over the bare sclera after pterygium excision and prevent its recurrence.

METHODS

After excision of the primary pterygium, we performed simple conjunctival epithelial transplantation (SCET) in which we glued an amniotic membrane patch pre-loaded with tiny autologous conjunctival tissue fragments over the scleral defect. Slit-lamp evaluation was performed at 2 and 7-10 days, and then at 1, 3, 6, and 12 months after surgery, together with confocal microscopy at 3, 6, and 12 months.

RESULTS

Surgical excision and SCET for nasal primary pterygium were performed in 6 eyes (6 patients). No graft detachment occurred. An inflammatory granuloma was excised without sequelae in one patient 2 months after surgery. No signs of recurrence or sight-threatening complications were recorded at 12 months, and in vivo confocal microscopy showed progressive expansion of the conjunctival cell population and formation of a clear corneal-conjunctival transition.

CONCLUSIONS

SCET takes advantage of the ability of the amniotic membrane and conjunctival cells to renew. Outcomes after SCET are comparable to conventional conjunctival flap surgery and can be achieved in less surgical time and with less donor tissue to be removed.

Atypical U3 snoRNA Suppresses the Process of Pterygium Through Modulating 18S Ribosomal RNA Synthesis

Background

The progression and recurrence of pterygium mainly occur due to the abnormal proliferation and migration of stromal pterygium fibroblasts. This research explores the aberrant expression of small nucleolar RNA U3 (U3 snoRNA) in pterygium and elucidates the molecular mechanisms of U3 snoRNA in pterygium development.

Methods

Primary human conjunctival fibroblasts (HCFs) and human pterygium fibroblasts (HPFs) were separated and cultured from fresh conjunctiva grafts and pterygium tissues. The PLKO.1 lentiviral system and CRISPR/Cas9 recombinant construct were, respectively, used to overexpress and silence U3 snoRNA in HPFs and HCFs for further specific phenotype analysis. RNA-seq and TMT-labeled quantitative protein mass spectrometry were utilized to evaluate the effect of U3 snoRNA on mRNA transcripts and protein synthesis.

Results

Reduced U3 snoRNA in pterygium promotes HCF or HPF cells’ proliferation, migration, and cell cycle but has no significant effect on apoptosis. U3 snoRNA modulates 18S rRNA synthesis through shearing precursor ribosomal RNA 47S rRNA at the 5′ external transcribed spacer (5′ ETS). Moreover, the altered U3 snoRNA causes mRNA and protein differential expression in HCF or HPF cells.

Conclusions

The atypical U3 snoRNA regulates the translation of specific proteins to exert a suppressive function in pterygium through modulating the 18S rRNA synthesis. Here, we uncover a novel insight into U3 snoRNA biology in the development of pterygium.

Vascular Endothelial Growth Factor expression patterns in non- Human Papillomavirus - related pterygia: an experimental study on cell spot arrays digital analysis

PURPOSE

The role of angiogenic factors -such as vascular endothelial growth factor (VEGF) - in development and progression of pterygia lesions remains under investigation. In the current study, we analyzed VEGF protein expression in a series of pterygia and normal conjunctiva epithelia.

METHODS

Using a liquid based cytology assay, thirty (n = 30) cell specimens were obtained by applying a smooth scraping on conjunctiva epithelia and fixed accordingly. None of them had a history of Human Papillomavirus (HPV) infection. Similarly, the same process was applied also in normal conjunctiva epithelia (n = 10; control group). We constructed five (n = 5) slides each containing eight (n = 8) cell spots. An immunocytochemistry (ICC) assay was implemented. Digital image analysis was also performed for evaluating objectively the corresponding immunostaining intensity levels.

RESULTS

All the examined pterygia cell samples over expressed the marker. High staining intensity levels were detected in 15/30 (50%), whereas the rest 15/30 (50%) demonstrated moderate expression. Overall VEGF expression was statistically significantly higher in pterygia compared to normal conjunctiva epithelia (p=.0001). Concerning the other parameters, VEGF protein expression did not associate with the gender of the patients (p = 0.518), the presence of recurrent lesion (p = 0.311), the anatomical location (p = 0.191) or with their morphology (p = 0.316). Interestingly, the recurrent lesions demonstrated the highest levels of VEGF expression.

CONCLUSIONS

VEGF over expression is a frequent event in pterygia playing a potentially central molecular role in the progression of the lesion. Cell spot array analysis -based on liquid cytology- seems to be an innovative, easy to use technique for analyzing a broad variety of molecules in multiple specimens on the same slide by applying different ICC assays.

A novel lncRNA lnc-PPRL promotes pterygium development by activating PI3K/PDK1 signaling pathway

A sight threatening, pterygium is a common proliferative and degenerative disease of the ocular surface. LncRNAs have been widely studied in the occurrence and development of various diseases, however, the study of lncRNAs in pterygium has just relatively lacking. In the present study, we performed the high-throughput RNA sequencing (HTS) technology to identify differentially expressed lncRNAs in pterygium. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were carried out to forecast the regulatory and functional role of lncRNAs in pterygium. Notably, we identified a novel lncRNA, LOC102724238, which we named pterygium positively-related lncRNA (lnc-PPRL), was up-regulated in pterygium. Lnc-PPRL showed to be preferentially accumulated in cytoplasm, and it can promote cell proliferation, migration and invasion of human pterygium epithelium cells (hPECs). Further study of underlying mechanisms demonstrated that lnc-PPRL may exert its biological effect by activating canonical PI3K/PDK1 pathway, and subsequently promoting the activation of Akt/mTOR signaling pathway and its downstream effectors. Interestingly, lnc-PPRL was also proved to influence YAP nuclear localization. Taken together, our study firstly suggested that the "big molecule" lnc-PPRL have potential as a novel therapeutic target for the prevention and treatment of pterygium.

Computer-Assisted Pterygium Screening System: A Review

Pterygium is an eye condition that causes the fibrovascular tissues to grow towards the corneal region. At the early stage, it is not a harmful condition, except for slight discomfort for the patients. However, it will start to affect the eyesight of the patient once the tissues encroach towards the corneal region, with a more serious impact if it has grown into the pupil region. Therefore, this condition needs to be identified as early as possible to halt its growth, with the use of simple eye drops and sunglasses. One of the associated risk factors for this condition is a low educational level, which explains the reason that the majority of the patients are not aware of this condition. Hence, it is important to develop an automated pterygium screening system based on simple imaging modalities such as a mobile phone camera so that it can be assessed by many people. During the early stage of automated pterygium screening system development, conventional machine learning techniques such as support vector machines and artificial neural networks are the de facto algorithms to detect the presence of pterygium tissues. However, with the arrival of the deep learning era, coupled with the availability of large training data, deep learning networks have replaced the conventional networks in screening for the pterygium condition. The deep learning networks have been successfully implemented for three major purposes, which are to classify an image regarding whether there is the presence of pterygium tissues or not, to localize the lesion tissues through object detection methodology, and to semantically segment the lesion tissues at the pixel level. This review paper summarizes the type, severity, risk factors, and existing state-of-the-art technology in automated pterygium screening systems. A few available datasets are also discussed in this paper for both classification and segmentation tasks. In conclusion, a computer-assisted pterygium screening system will benefit many people all over the world, especially in alerting them to the possibility of having this condition so that preventive actions can be advised at an early stage.

Histopathological Rate of Ocular Surface Squamous Neoplasia in Clinically Suspected Pterygium Specimens: 10-Year Results

PURPOSE

The aim of this study was to evaluate the prevalence of histopathologically confirmed ocular surface squamous neoplasia (OSSN) in clinically diagnosed pterygium samples at a tertiary center in Northern California, over a 10-year period (2009-2019).

METHODS

A retrospective chart review of patients older than 18 years with clinically diagnosed benign pterygium requiring excision was conducted. Clinically suspected pterygia were excised using standard techniques and routinely submitted to the University of California Davis for pathologic evaluation. Demographic, clinical, surgical, and pathological information were recorded and analyzed. The prevalence rate of OSSN was calculated.

RESULTS

A total of 348 consecutive specimens were evaluated. The mean (±SD) age of the patients was 58 ± 12 years, with a near equal sex representation. A total of 57 (16%) pterygia were recurrent at initial presentation. Histopathologic results demonstrated a single case of OSSN. This patient did not have a documented history of carcinoma in other organs or any history of herpes virus, human papilloma virus, or human immunodeficiency virus infection.

CONCLUSIONS

The prevalence of histopathological OSSN in clinically suspected pterygia within our sample was approximately 0.3%. Because of shared clinical characteristics of pterygia and OSSN, a high index of suspicion and judicious use of anterior segment optical coherence tomography enable for effective preoperative diagnosis of OSSN. However, in the absence of clinical expertise or high-resolution optical coherence tomography, routine tissue pathologic examination may be warranted.

Effect of Pterygium Removal Combined with Conjunctival Autograft on Corneal Parameters in Swept-Source Imaging

Background: Both pterygium ingrowth and excision determine alterations in corneal topography. The aim of this study was to evaluate the influence of pterygium removal combined with conjunctival autografts in addition to the use of human fibrin tissue glue on changes in corneal parameters as measured by 3-D swept-source anterior segment optical coherence tomography (AS-OCT) imaging. Methods: Sixteen eyes (16 patients) with pterygium that qualified for surgical treatment were enrolled in this study. Eye examination, slit lamp, and 3-D AS-OCT (CASIA 2) assessment were performed before the surgery and 7 days, 1 month, and 6 months after pterygium excision. Topographic parameters of both anterior and posterior surfaces of the cornea were analysed at each follow-up visit. Results: The gradual decrease in total astigmatism power from preoperative median 2.75 (6.15) D to 1.2 (1.1) D at 6-month follow-up (p = 0.034) was noted from the day 7 visit. Values were strongly influenced by variations of anterior cornea astigmatism. In contrast, a gradual total HOA reduction at the 1-month (from median 0.79 (1.3) D to 0.44 (0.27) D; p = 0.038) and at 6-month visits (0.25 (0.09); p = 0.001) was observed. Similarly, values were strongly influenced by variations of the anterior. Additionally, total average keratometry values increased from preoperative 44.05 (2.25) D to 44.6 (1.9) (p = 0.043) 1 month after the surgery. Conclusions: Significant steepening of the anterior cornea and a reduction in both astigmatism and HOA were observed after pterygium excision. The anterior corneal surface was an essential component of the total postoperative corneal topography values. Three-dimensional swept-source AS-OCT imaging seems to be a valuable tool for monitoring both the progression of the disease and postoperative effects in pterygium eyes.

Comparison of pterygium recurrence with and without using postsurgical topical cyclosporin a 0.05%: A randomized clinical trial

Purpose:

To evaluate the efficacy of 3-month administration of topical cyclosporin A (CsA) 0.05% on postoperative recurrence after pterygium surgery.

Methods:

In this randomized clinical trial, 78 patients undergoing pterygium surgery (using the rotational conjunctival flap technique with mitomycin C [MMC]) were enrolled and randomly allocated into the control (n = 39) and case (CsA) (n = 39) groups in a single-blind method. The patients were examined on postoperative days 1, 3, and 7 and months 1, 3, and 6, and their best-corrected visual acuity, intraocular pressure, clinical inflammation, postoperative complications, and recurrence were compared.

Results:

The mean age of patients was 53.22 ± 9.99 years; most (57.7%) of them were men. The two groups were not different in terms of demographics, pterygium size, or pterygium grade. The clinical inflammation at the first and third postoperative months was not different between the groups (P = 0.108 and 0.780, respectively). No serious complications were detected; complication rates were not different between the groups (P = 0.99). The recurrence rate was 5.1% in the case group and 7.7%% in the control group (P = 0.99).

Conclusion:

The present study showed no priority for 3-month administration of CsA 0.05% drops on postoperative outcomes, including prevention of pterygium recurrence, complications, and inflammation after the rotational conjunctival autograft technique with MMC.

Surgical Preferences in the Management of Primary Pterygium among Anterior Segment Specialists

Purpose:

The purpose of this study is to reflect anterior segment specialists’ current practice pattern regarding the management of primary pterygium.

Methods:

A 24-item survey regarding indications for surgery, different surgical techniques, use of adjuvant pharmacological therapy, type of intraoperative and postoperative pharmacological therapy, and the preferred treatment of early recurrences was sent to members of the Saudi Ophthalmological Society (SOS) and practicing cornea experts including consultants, specialists, and fellows in Saudi Arabia.

Results:

A total of 61 cornea specialists completed the questionnaire (response rate 49%). More than 95% considered the proximity of the pterygium to the visual axis an indication for excision. The most frequent technique for pterygium excision was extensive head and conjunctival resection, including the base (69%) and intermediate resection of the Tenon's capsule (53%). For conjunctival replacement, conjunctival autograft was preferred by 79%, amniotic membrane (54%), and simple conjunctival closure (46%). Interrupted vicryl sutures, fibrin glue, and combined sutures and tissue adhesive were the preferred graft fixation conveyed by 85%, 46%, and 34% of our experts, respectively. An estimated recurrence rate of 1-5% was stated by 29% of respondents and 46% reported recurrence within 6 to 12 months. Half of the respondents specified using mitomycin C intraoperatively to prevent early pterygium recurrences. When recurrence occurred, corticosteroid was the agent of choice.

Conclusion:

This study set out to reflect the practice pattern of anterior segment specialists regarding the management of primary pterygium, and it may serve as an insight for further studies to define the optimal management of pterygium.

Impact of fibrin glue versus suture closure on double-headed pterygia in Asian eyes - a 7-year study in a tertiary institution

BACKGROUND

To compare the recurrence rate and outcomes of double-headed pterygia using fibrin glue versus suture closure of conjunctival autograft.

METHODS

All patients with double-headed pterygia who underwent pterygia excision with conjunctival autograft from January 2012 to January 2019 in the National University Hospital of Singapore were included. Patients were divided into 2 groups depending on whether fibrin glue or sutures were used to secure the conjunctival autograft in place. All patients had a minimum of 6 months follow-up.

RESULTS

A total (26 patients) of 22 eyes had fibrin glue, while eight eyes underwent suture closure of their conjunctival autograft. Fibrin glue group had 4.5% recurrence rate, while suture group had 37.5% recurrence rate (p = .021). There is statistically significant improvement for overall visual acuity (p = .009) and cylinder (p = .002). There is also statistically significant improvement for visual acuity in the glue group (p = .026), but not in the suture group. Fibrin glue group had a shorter operation duration time compared to suture group (p < .001).There were no cases of graft dislocation, contraction or limbal stem cell deficiency.

CONCLUSIONS

Low recurrence rates and good postoperative visual outcomes can be achieved with the split conjunctival autograft technique. Our study suggests that fibrin glue has an additional benefit over the use of sutures in the management of these complex cases.

Implementation and Application of an Intelligent Pterygium Diagnosis System Based on Deep Learning

Objective: This study aims to implement and investigate the application of a special intelligent diagnostic system based on deep learning in the diagnosis of pterygium using anterior segment photographs.

Methods: A total of 1,220 anterior segment photographs of normal eyes and pterygium patients were collected for training (using 750 images) and testing (using 470 images) to develop an intelligent pterygium diagnostic model. The images were classified into three categories by the experts and the intelligent pterygium diagnosis system: (i) the normal group, (ii) the observation group of pterygium, and (iii) the operation group of pterygium. The intelligent diagnostic results were compared with those of the expert diagnosis. Indicators including accuracy, sensitivity, specificity, kappa value, the area under the receiver operating characteristic curve (AUC), as well as 95% confidence interval (CI) and F1-score were evaluated.

Results: The accuracy rate of the intelligent diagnosis system on the 470 testing photographs was 94.68%; the diagnostic consistency was high; the kappa values of the three groups were all above 85%. Additionally, the AUC values approached 100% in group 1 and 95% in the other two groups. The best results generated from the proposed system for sensitivity, specificity, and F1-scores were 100, 99.64, and 99.74% in group 1; 90.06, 97.32, and 92.49% in group 2; and 92.73, 95.56, and 89.47% in group 3, respectively.

Conclusion: The intelligent pterygium diagnosis system based on deep learning can not only judge the presence of pterygium but also classify the severity of pterygium. This study is expected to provide a new screening tool for pterygium and benefit patients from areas lacking medical resources.

Effect of 2% Hyaluronic Acid on the Rate of Healing of Corneal Epithelial Defect After Pterygium Surgery: A Randomized Controlled Trial

Purpose

The study aimed to investigate the effects of 2% hyaluronic acid (HA) on corneal epithelial defect after pterygium surgery in comparison with the control group, measured in terms of the healing rate of corneal epithelial defect and pain score after surgery.

Methods

In this double-blind randomized clinical trial, fifty patients with primary pterygium were randomized into 2 groups: a control group or the group treated with a single topical application of 2% HA. Comprehensive ophthalmological examinations included measuring the area of corneal epithelium defect using ImageJ freeware and the pain score assessment after the operation.

Results

The mean and SD of the area of epithelial defect measured on postoperative Day 0, 1, and 2 were 10.89 ± 1.33 mm², 5.04 ± 0.87mm², and 2.44 ± 0.74 mm² for the HA group, and 11.14 ± 1.11 mm², 7.74 ± 1.17 mm², and 5.31 ± 1.15 mm² for the control group, respectively. While the initial area of the defect on Day 0 was essentially the same for both groups (p = 0.478), the area of the defect in the HA group was significantly smaller on both Day 1 and Day 2 (p < 0.001, p < 0.001), respectively. Similarly, the HA group exhibited a statistically significant higher rate of healing for the cornea epithelial defect over Day 0 and 1 compared to the control group (5.85 ± 0.89 mm²/day vs 3.14 ± 1.28 mm²/day, p < 0.001), respectively. The median (range) pain scores were evaluated at Day 0 was 7 (4–10) in the HA group and 7 (3–10) in the control group (p = 0.953). There was no statistically significant difference between two groups (p > 0.05) for Days 1, 2, and 3.

Conclusion

A single topical application of 2% HA tended to accelerate the healing process of corneal epithelium defect after pterygium surgery without any observable adverse effects during short-term follow-up.

Association between HPV detection in swab samples and tissue specimens and ophthalmic pterygium recurrence

PURPOSE

To investigate the presence of HPV on the ocular surface after surgical excision of HPV infected pterygia and the possible correlation of HPV with pterygium postoperative recurrence.

MATERIALS AND METHODS

Both exfoliative pterygium swab samples and respective tissue specimens were received and analyzed with real-time PCR for the detection of HPV-infected pterygia. In addition, swab samples from patients that had HPV-infected pterygia with no recurrence after 1 year of follow-up, as well as swab samples from patients with healthy conjunctiva, were analyzed.

RESULTS

Forty eyes with pterygium of 40 patients and 40 eyes with normal conjunctiva were included in the study. HPV virus was detected in the tissue specimens of 11 patients (27.5%) and in the swabs of 9 patients (22.5%). The HPV subtypes detected were 33, 39, 45, 56, 59, 66, and 68. The swab test had sensitivity of 81.82% and 100% specificity. In 15 (43%) patients, a bare sclera technique was used for pterygium removal and eleven of these patients showed recurrence of the disease. Surgical excision with use of autologous conjunctival graft was performed in twenty patients and five of them had recurrence. Patients with recurrent disease were 12.41 times more likely to have an HPV-infected pterygium (p = 0.031). Furthermore, from the 11 HPV positive patients, six had no recurrence, 1 year after surgery. In five of them, a swab sample was taken from the site of the surgical excision 1 year after surgery and real-time PCR was negative for HPV presence.

CONCLUSION

Persistence of HPV infection seems to be correlated with postoperative pterygium recurrence. Further investigation with the use of the minimally invasive proposed swab technique may contribute in the understanding of pterygium pathogenesis and in the development of a more efficient treatment planning.

Comparison of Corneal Irregularity After Recurrent and Primary Pterygium Surgery Using Fourier Harmonic Analysis

Purpose

To the best of our knowledge, few detailed investigation of astigmatism with recurrent pterygium currently exists. We aimed to evaluate corneal irregularity after recurrent pterygium surgery.

Methods

This observational study included consecutive patients who underwent recurrent pterygium surgery and were observed for >12 months postoperatively via corneal examination. Patients who underwent primary pterygium surgery during the same period served as controls. Pterygium size and corneal irregularity evaluated with Fourier harmonic analysis (spherical component, regular astigmatism, asymmetry component, and higher-order irregularity) were compared between groups preoperatively and at 1, 3, 6, and 12 months postoperatively.

Results

Overall, 203 eyes of 203 patients (age, 66.5 ± 9.5 years) were included, of which 44 eyes had recurrent pterygium and 159 had primary pterygium. Regular astigmatism in the recurrent pterygium group was higher than that in the primary pterygium group preoperatively and at 1 and 3 months postoperatively. The asymmetry component and higher-order irregularity in the recurrent pterygium group were higher than those in the primary pterygium group at all observation points.

Conclusions

Fourier harmonic analysis showed that larger corneal irregularity that could not be corrected with spectacles persisted for a long time after recurrent pterygium excision than after primary pterygium excision. Thus, recurrence prevention is critical for primary pterygium surgery.

Translational Relevance

We demonstrated that larger corneal irregularity that could not be corrected with spectacles remained long after excision of recurrent pterygium compared with excision of primary pterygium; thus, the prevention of recurrence is clinically important for primary pterygium surgery in terms of corneal irregularity.

Efficacy of bevacizumab in the treatment of pterygium: An updated meta-analysis of randomized controlled trials

Recurrence is the most common problem following pterygium surgery. Whether bevacizumab can prevent pterygium recurrence is controversial. To address this point, we carried out a meta-analysis of randomized controlled trials evaluating the efficacy and safety of bevacizumab in the treatment of pterygium. We searched the PubMed, EMBASE, Cochrane Library, Web of Science, Chinese Biomedical Literature, China National Knowledge Infrastructure, and Wan fang databases up to September 20, 2020 for relevant articles. We used the Cochrane assessment tool to evaluate the methodologic quality of the included studies, and calculated the relative risk (RR) and 95% confidence interval (CI) of the reported recurrence and complication rates. A total of 17 studies including 1124 patients with 1144 eyes were included in the meta-analysis. The combined results showed that bevacizumab significantly reduced the recurrence rate of pterygium after surgery (RR = 0.652, 95% CI: 0.504-0.845, Z = 3.24, P = 0.001) and was not significantly associated with the occurrence of postoperative complications compared to control treatments (RR = 0.832, 95% CI: 0.604-1.145, Z = 1.13, P = 0.259). A subgroup analysis showed that the rate of pterygium recurrence was significantly lower with bevacizumab than in the control group at a dose of 2.5 mg (RR = 0.47, 95% CI: 0.24-0.91) administered by subconjunctival injection (RR = 0.54, 95% CI: 0.39-0.75) after a follow-up time of ≤ 6 months (RR = 0.63, 95% CI: 0.45-0.88). Thus, bevacizumab can reduce the risk of pterygium recurrence after surgery, and does not differ from placebo or other drug treatments in terms of the risk of complications.

Biological tissues and components, and synthetic substrates for conjunctival cell transplantation

The conjunctiva is the largest component of the ocular surface. It can be damaged by various pathological processes leading to scarring, loss of tissue and dysfunction. Depending on the amount of damage, restoration of function may require a conjunctival graft. Numerous studies have investigated biological and synthetic substrates in the search for optimal conditions for the ex vivo culture of conjunctival epithelial cells that can be used as tissue grafts for transplantation. These substrates have advantages and disadvantages that are specific to the characteristics of each material; the development of an improved material remains a priority. This review is the second of a two-part review in The Ocular Surface. In the first review, the structure and function of the conjunctiva was evaluated with a focus on the extracellular matrix and the basement membrane, and biological and mechanical characteristics of the ideal substrate with recommendations for further studies. In this review the types of biological and synthetic substrates used for conjunctival transplantation are discussed including substrates based on the extracellular matrix. .

Pterygium: an update on pathophysiology, clinical features, and management

Pterygium is a relatively common ocular surface disease. The clinical aspects and the treatment options have been studied since many years ago, but many uncertainties still exist. The core pathologic pathway and the role of heredity in the development of pterygium are still attractive fields for the researchers. The role of pterygium in corneal irregularities, in addition to the refractive properties of pterygium removal, has been increasingly recognized through numerous studies. The association between pterygium and ocular surface neoplasia is challenging the traditional beliefs regarding the safe profile of the disease. The need for a comprehensive clinical classification system has encouraged homogenization of trials and prediction of the recurrence rate of the pterygium following surgical removal. Evolving surgical methods have been associated with some complications, whose diagnosis and management are necessary for ophthalmic surgeons. According to the review, the main risk factor of pterygium progression remains to be the ultraviolet exposure. A major part of the clinical evaluation should consist of differentiating between typical and atypical pterygia, where the latter may be associated with the risk of ocular surface neoplasia. The effect of pterygium on astigmatism and the aberrations of the cornea may evoke the need for an early removal with a purpose of reducing secondary refractive error. Among the surgical methods, conjunctival or conjunctival-limbal autografting seems to be the first choice for ophthalmic surgeons because the recurrence rate following the procedure has been reported to be lower, compared with other procedures. The use of adjuvant options is supported in the literature, where intraoperative and postoperative mitomycin C has been the adjuvant treatment of choice. The efficacy and safety of anti–vascular endothelial growth factor agents and cyclosporine have been postulated; however, their exact role in the treatment of the pterygium requires further studies.

The Effect of a Novel Strategy in Treating Primary Pterygium: A Prospective Randomized Clinical Study

OBJECTIVE

We sought to compare the efficacy and safety of conjunctival autograft (CAG), amniotic membrane transplantation (AMT) with postoperative interferon alfa-2b (IFN alfa-2b), and modified conjunctival autograft plus amniotic membrane transplantation (mCAG plus AMT) with postoperative IFN alfa-2b for primary pterygium.

DESIGN

Randomized controlled clinical trial.

METHODS

Eyes with nasal and primary pterygia were randomized in a 1:1:1 ratio to receive CAG, AMT with IFN alfa-2b, or mCAG plus AMT with IFN alfa-2b. Subjects were followed up for 12 months. Primary outcomes included recurrence rate and complications. Secondary outcomes included corneal epithelium status, ocular surface symptom score, and visual acuity change.

RESULTS

Eighty-five subjects (30 in the CAG group, 25 in the AMT group, and 30 in the CAG+AMT group) completed the 12-month follow-up. No complication or grade 4 recurrence was found. There was no significant difference among the 3 groups in recurrence grade, corneal epithelium status, and visual acuity change. Compared with mCAG+AMT, CAG has a negative effect (β = -0.62, P = .001), and AMT has a negative effect (β = -2.02, P < .001) on postoperative symptom scores. Compared with AMT, CAG has a positive effect (β = 1.28, P < .001) on postoperative symptom scores.

CONCLUSIONS

All 3 strategies had good safety and clinical efficacy in the study. Compared with conjunctival autograft, the 2 surgeries using no autograft or limited autograft was less traumatic and gave more flexibility for future ocular surface condition changes.

Cosmetic outcome of femtosecond laser-assisted pterygium surgery

Background

To examine the cosmetic outcome of femtosecond laser-assisted pterygium surgery (FLAPS) with conjunctival autograft (CAG) and its potential predictive factors.

Methods

This was a prospective interventional case series (NCT02866968). We included 29 patients (29 eyes) with primary pterygium who underwent FLAPS. Cosmetic outcome was graded by two graders (an ophthalmology resident and an experienced ophthalmologist) using Hirst classification system (1–4 = excellent–poor). Weighted Cohen’s kappa analysis was performed to examine the intra- and inter-rater reliability. The relationship between cosmetic outcome and various factors were determined by Spearman’s correlation coefficients (r).

Results

The preoperative severity of pterygium (Tan grading system) was mild/atrophic (7%), moderate/intermediate (62%), and severe/fleshy (31%). An ultrathin CAG (mean thickness of 74.5 ± 9.8 μm) was fashioned intraoperatively. An excellent cosmetic outcome of FLAPS (median ± IQR) was observed at 3 months (1.0 ± 1.0) and remained similar at 6 months (1.0 ± 0.0) and 12 months (1.0 ± 0.0) postoperatively. At final follow-up, 27 (93%) patients achieved good-to-excellent cosmetic outcome, with 1 (3%) patient having a poor outcome due to incomplete pterygium removal. Weighted kappa analysis of Hirst grading system showed excellent intra-rater (κ = 0.86–0.95) and inter-rater reliability (κ = 0.84–0.88). There was a weak and borderline significant correlation between good cosmetic outcome and reduced postoperative CAG thickness (r = 0.38, P = 0.06) but not with age, gender, preoperative pterygium severity, or intraoperative CAG thickness.

Conclusions

FLAPS can result in an excellent cosmetic outcome, which may be attributed to the beneficial effect of an ultrathin CAG.

Trial registration

ClinicalTrials.gov, NCT02866968. Registered in July 2016,

Supplementary Information

The online version contains supplementary material available at 10.1186/s40662-021-00230-w.

Evaluation of Conjunctival Autografting Augmented with Mitomycin C Application versus Ologen Implantation in the Surgical Treatment of Recurrent Pterygium

Objectives

To evaluate the safety and efficacy of augmenting conjunctival autografting with intraoperative mitomycin C (MMC) application versus Ologen implantation in the management of recurrent pterygium.

Materials and Methods

This prospective randomised study included 63 eyes of 63 patients, with recurrent nasal pterygium, who presented to the outpatient clinic of Menoufia University Hospital in Shebin El Kom and Manshiet Soltan from January 2016 to December 2019. Patients were randomly enrolled into two groups. Group A included 32 eyes of 32 patients who underwent conjunctival autografting augmented with the topical application of MMC (0.2 mg/mL), and group B included 31 eyes of 31 patients who underwent conjunctival autografting augmented with Ologen implantation. All the patients underwent follow-up examinations for a period of 24 months. During each visit, a complete ophthalmic examination was performed. Pterygium regrowth of 1 mm or more, over the cornea, was considered a recurrence.

Results

In the MMC group, no recurrence was reported during the 24-month follow-up period. In the Ologen implantation group, recurrence was reported in 2 (8%) eyes. The time interval from surgery to recurrence was 5 months in one case and 8 months in the other. No other serious postoperative complications were reported, and there was no statistically significant difference between the groups in this regard.

Conclusion

Ologen implantation with conjunctival autografting shows promising results in the surgical management of recurrent pterygium with mild non-vision-threatening postoperative complications comparable to that of MMC application with conjunctival autografting. Registration number: ClinicalTrials.govNCT04419038.

Pterygium excision with modified bare sclera technique combined with mitomycin C

PURPOSE

Numerous surgical methods, with varying rates of recurrence, have been applied for the treatment of pterygium. Adjuvant mitomycin C (MMC) application has shown promising results in the prevention of recurrence. Here we propose and describe modified bare sclera technique combined with the intraoperative application of MMC for pterygium excision.

STUDY DESIGN

Retrospective study.

METHODS

Primary pterygium patients who underwent pterygium excision via the bare sclera combined with 0.04% MMC technique from January 2014 to December 2016 were reviewed. In all patients, the subconjunctival pterygium strand was exposed and then sufficiently excised in combination with the safe use of MMC; i.e., the prevention of MMC dilution and diffusion to surrounding tissue. Surgical complications, recurrence rates, and recurrence onset were recorded.

RESULTS

This study involved 32 primary pterygium eyes (grade T1 = 22 eyes; 68.7%). The mean postoperative follow-up period was 26.4 ± 14.5 months (range: 12-60 months). MMC was applied for 1-3 min. The mean complete epithelialization was 12.6 ± 7.6 days and no surgical complications were observed. In 1 patient with double-head primary pterygium, recurrence occurred at 15-months postoperative.

CONCLUSIONS

The modified bare sclera technique combined with MMC application was found to be safe, effective, and presents good cosmetic appearance for the treatment of primary pterygium when safety points are strictly applied.

[Lamellar keratoplasty in the management of recurrent pterygium]

As it is known, the main problem of surgical treatment of pterygium is associated with high risk of recurrence. Quite a number of surgical techniques now exist, all aimed at pterygium removal and only differing in the method of conjunctival closure following the excision. Due to relatively low recurrence rates, conjunctival or conjunctival-limbal autografts are currently the 'gold standard' of pterygium surgery. The frequency of recurrence is also insignificant in peripheral anterior lamellar keratoplasty, which is rarely performed due to its complexity and the need for donor cornea. However, it is considered to be the method of choice in cases of repeated recurrence as well as in patients with high pterygium activity. This article describes a clinical case of a massive recurrent pterygium (grade IV, activity level 3). The patient has had three previous surgeries (including conjunctival autotransplantation) that yielded no success. By performing large-diameter peripheral anterior lamellar keratoplasty in combination with adjuvant therapy (intraoperative mitomycin C and subconjunctival postoperative aflibercept injections), structural integrity of the cornea was finally restored without further recurrences and visual acuity was increased.

Clinical Outcomes of Silk versus Nylon Sutures for Suturing of Conjunctival Autograft in Pterygium Surgery

PURPOSE:

The purpose is to compare the clinical results of using silk versus nylon sutures for conjunctival autograft suturing in pterygium surgery.

METHODS:

In this prospective, randomized, controlled, clinical trial 50 eyes from 50 patients with primary nasal pterygium were randomized to undergo pterygium surgery with the use of either nylon sutures or silk sutures for conjunctival autograft suturing. Patients were followed up for 6 months. Main outcome measures included recurrence, postoperative discomfort according to a visual analog scale (VAS), graft hyperemia, and graft edema.

RESULTS:

According to the results, there was no significant difference between groups regarding recurrence rate of pterygium (P = 0.72). A significant decrease in the mean VAS discomfort score from day 1 to day 14 was observed in both groups (P = 0.001); postoperative discomfort during the first 2 weeks, was not significantly different between the two groups. At 2 weeks' postoperatively, significantly greater number of nylon sutures remained on the autograft (P = 0.021), some of which were buried and could not be removed.

CONCLUSION:

Both silk and nylon are effective suture materials for autograft suturing in pterygium surgery with similar postoperative discomfort and recurrence rate. Significantly greater number of nylon sutures remains buried on the autograft and could not be removed easily.

Recurrent pterygium – features of surgical treatment

Pterygium is a fibrovascular degenerative condition of the subconjunctival tissue that proliferates and grows into the cornea in the form of a vascularized fold, destroying the surface layers of the stroma and Bowmans membrane. This disease is common throughout the world. The etiology is not clear, but it is known that the appearance of pterygium is associated with exposure of the eye to ultraviolet rays. The treatment of the de novo occurring pterygium is a relatively simple task and involves surgical removal. But a simple excision is currently unacceptable due to the high recurrence rate. In order to minimize the risk of relapse, numerous adjuvant treatment methods are used, which include anti-metabolites such as Mitomycin C and 5-fluorouracil, amniotic membrane, various types of conjunctival and or limbal grafts; medications such as anti-vascular endothelial growth factor are sometimes used. In the clinical case presented in the article, we successfully used the technique of anterior lamellar keratoplasty and autoconjunctival transplantation in combination with intra-operative use of anti-metabolite Mitomycin C in a young patient with recurrent stage IV pterygium (degree of activity 3) twice unsuccessfully operated on. As a result of this surgical technique, the transparency of the cornea was restored and high visual acuity was obtained.

Proposal and validation of a new grading system for pterygium (SLIT2)

BACKGROUND/AIMS

To propose and validate a new pterygium grading system based on slit-lamp evaluation.

METHODS

This prospective cross-sectional study included 217 patients with pterygium. All patients underwent slit-lamp examination, and slit-lamp photographs were independently graded by two graders twice. A total of eight parameters were evaluated and all parameters were assigned with a score of 1-4 (normal-severe). Intra-rater and inter-rater reliability as determined by weighted Cohen's kappa analysis.

RESULTS

A total of 868 independent assessment, based on 217 slit-lamp images, were performed by two graders. For conjunctival assessment, the intra-rater reliability was excellent for body thickness (κ=0.81-0.89) and size at limbus (κ=0.87-0.92), substantial-to-excellent for body vascularity (κ=0.72-0.86), and moderate-to-excellent for body length (κ=0.57-0.81), whereas the inter-rater reliability was excellent for size at limbus (κ=0.86), substantial for body thickness (κ=0.72-0.73) and body vascularity (κ=0.66-0.75), and moderate for body length (κ=0.54-0.57). For corneal assessment, the intra-rater reliability was excellent for all four parameters (κ=0.84-0.90) whereas the inter-rater reliability was excellent for head length (κ=0.86-0.87), substantial-to-excellent for head vascularity (κ=0.78-0.82), substantial for Stocker's line (κ=0.79-0.80) and head thickness (κ=0.67-0.69). The grading system was named SLIT2, which included S tocker's line, S ize at limbus, L ength of head/body, I njection/vascularity of body/head, and T hickness of body/head.

CONCLUSION

The proposed SLIT2 grading system, consisting of eight components, may serve as a reliable tool to standardise the reporting of pterygium severity and disease recurrence for clinical and research applications.

Long-term changes and effect of pterygium size on corneal topographic irregularity after recurrent pterygium surgery

This retrospective observational study compared long-term topographic changes after recurrent- and primary-pterygium surgery depending on pterygium size. Patients who underwent recurrent-pterygium excision between 2002–2013 and age, sex, and pterygium size-matched controls who underwent primary-pterygium surgery were included (33 eyes of 33 patients in each group). Pterygium size was graded per advancing edge position: <1/3 of corneal diameter (grade 1), outside the pupil (grade 2), and within the pupillary area (grade 3). Surface asymmetry index (SAI), surface regularity index (SRI) in corneal topography, and uncorrected and best-spectacle-corrected visual acuity were compared before and 1, 3, 6, and 12 months postoperatively. Three, 17, and 13 eyes had grades 1, 2, and 3, respectively. In grade 2, the SAI and SRI were respectively significantly larger at all observation points (p = 0.01, 0.03, 0.02, 0.02, and 0.004) and before and 6 and 12 months postoperatively (p = 0.02, 0.04, and 0.03) in recurrent pterygium. In grade 3, the SAI was significantly larger before and 1, 3, and 12 months postoperatively (p = 0.04, 0.01, 0.01, and 0.02) and the SRI was significantly larger before and 12 months postoperatively (p < 0.001, 0.02) in recurrent pterygium. Corneal irregularity persisted 12 months after recurrent-pterygium surgery compared with that in same-size primary pterygium.

A surgical skills assessment rubric for pterygium surgery

PURPOSE

To introduce an assessment tool (rubric) for evaluating ophthalmology residents' competency in pterygium surgery.

METHODS

A panel of experienced international surgeons collaborated and developed the rubric. After describing various stages of the procedure, the Dreyfus scale of skill acquisition was used for scoring each stage. After finalizing the rubric, two surgeons independently evaluated 20 masked pterygium surgery videos of 10 residents and scored the videos according to the rubric. The agreement between the scores of them was examined with the intra-class correlation coefficient test.

RESULTS

This rubric divides pterygium surgery into 13 different stages and covers the two most common techniques of pterygium surgery; conjunctival autograft and amniotic membrane transplant. The rubric showed face and content validity. Overall, an intraclass correlation coefficient of 0.90 (95% confidence interval 0.76-0.96, P < 0.001) was achieved between the two surgeons. The residents scored significantly higher on surgeries performed later in their rotation compared to the earlier surgeries (4.32 ± 0.35 vs 3.96 ± 0.31, P = 0.006). Certain stages of pterygium surgery were more strongly correlated with the residents' past pterygium surgical experience.

CONCLUSION

This study introduces an international rubric for assessing competency in pterygium surgery. In addition to face and content validity, this rubric shows high inter-rater reliability. This may be a useful tool for teaching and measuring competency in pterygium surgery.