An update on the surgical management of pterygium and the role of loteprednol etabonate ointment

Evaluation of scleral thickness in patients with pterygium

OBJECTIVES

To evaluate scleral thickness measurements of pterygium patients using anterior segment optical coherence tomography (AS-OCT) and to compare them with healthy individuals.

MATERIAL AND METHODS

Scleral thickness was measured from 2, 4, 6 mm posterior to the scleral spur with AS-OCT (Swept Source OCT Triton, Topcon, Japan) in 4 quadrants (superior, inferior, nasal and temporal).

RESULTS

Eyes with pterygium were determined as Group 1, and contralateral eyes without pterygium were determined as Group 2. Healthy controls were determined as Group 3. In the measurements made from 4 mm posterior, no significant difference was found between Group 1 and Group 2 in any quadrants (p > 0.05). In all measurements made from 4 mm posterior to the scleral spur, scleral thickness was found to be significantly higher in Group 1 compared to Group 3 (p < 0.05). Measurements made from 2 mm posterior to the scleral spur in Group 1 was found to be significantly higher in the superior and temporal quadrants compared to Group 3 (p = 0.05), while no significant difference was found in the nasal and inferior quadrants (p > 0.05). When Group 2 and Group 3 were compared, scleral thickness measurements made from 4 mm posterior to the scleral spur was significantly thicker in all quadrants in Group 2 (p > 0.05).

CONCLUSION

Scleral thickness was found to be higher in pterygium patients compared to healthy controls, especially when measured from 4 mm posterior to the scleral spur. It has been predicted that high scleral thickness may be associated with high fibroblast activity in subconjunctival structures, and this may predispose to pterygium.

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.

Pharmacological treatment strategies of pterygium: Drugs, biologics, and novel natural products

Pterygium is a fibrovascular tissue growth invading the cornea. Adjunctive treatment post-surgery includes conventional immunosuppressants as well as antiviral drugs. The use of large- and small-molecule antivascular endothelial growth factor (VEGF) agents remains an integral part of pterygium treatment as well as other neovascular conditions of the eye. Naturally occurring polyphenolic compounds have favorable characteristics for treating neovascular and inflammatory eye conditions, including good efficacy, stability, cost-effectiveness, and the versatility of their chemical synthesis. In this review, we discuss pharmacological treatments of pterygium. Natural products, such curcumin, ellagic acid, and chalcones, are reviewed, with emphasis on their potential as future pterygium treatments.

Transcriptome Analysis of Pterygium and Pinguecula Reveals Evidence of Genomic Instability Associated with Chronic Inflammation

Solar damage due to ultraviolet radiation (UVR) is implicated in the development of two proliferative lesions of the ocular surface: pterygium and pinguecula. Pterygium and pinguecula specimens were collected, along with adjacent healthy conjunctiva specimens. RNA was extracted and sequenced. Pairwise comparisons were made of differentially expressed genes (DEGs). Computational methods were used for analysis. Transcripts from 18,630 genes were identified. Comparison of two subgroups of pterygium specimens uncovered evidence of genomic instability associated with inflammation and the immune response; these changes were also observed in pinguecula, but to a lesser extent. Among the top DEGs were four genes encoding tumor suppressors that were downregulated in pterygium: C10orf90, RARRES1, DMBT1 and SCGB3A1; C10orf90 and RARRES1 were also downregulated in pinguecula. Ingenuity Pathway Analysis overwhelmingly linked DEGs to cancer for both lesions; however, both lesions are clearly still benign, as evidenced by the expression of other genes indicating their well-differentiated and non-invasive character. Pathways for epithelial cell proliferation were identified that distinguish the two lesions, as well as genes encoding specific pathway components. Upregulated DEGs common to both lesions, including KRT9 and TRPV3, provide a further insight into pathophysiology. Our findings suggest that pterygium and pinguecula, while benign lesions, are both on the pathological pathway towards neoplastic transformation.

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.

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.

Pterygium Surgery Utilizing Limbal Conjunctival Autograft and Subconjunctival Amniotic Membrane Graft in High-Risk Populations

Objective

To measure the outcomes of primary pterygium excision with a limbal conjunctival autograft when combined with the adjunctive use of a prophylactic subconjunctival graft of amniotic membrane to decrease the recurrence rate after surgery in an ethnically diverse population with a statistically higher risk for recurrence (African American, Asian, Caribbean, Asian, Latin).

Design

This is a retrospective, non-comparative study of post-operative outcomes.

Participants

A total of 355 patients, totaling 493 eyes, with clinically significant, primary pterygia.

Patients and Methods

Patients were enrolled into the study based on the need for pterygium surgery and if they underwent primary pterygium excision with conjunctival autograft with subconjunctival amniotic membrane placement. Patients with recurrent pterygium or those with pseudopterygium were excluded from this study. All surgeries took place at the Florida Eye Microsurgical Institute (Boynton Beach, FL) between June 2006 and October 2013 by a single surgeon (BAS). Patients were seen on post-operative day 1, 7, 30, 90, 180 and 365 to evaluate for pterygium recurrence. Pterygium recurrence is defined in this study as growth greater than 1 mm past the corneal limbus at or after 6 months.

Results

There were six cases of recurrent pterygium for a recurrence rate of 1.22% ± 0.97% (n=493, p=0.05). Follow-up ranged from 6 months to 6 years (mean 28 months).

Conclusion

Primary pterygium excision with a limbal conjunctival autograft and placement of a subconjunctival amniotic membrane graft has a low recurrence rate consistent with previously published data.

Transcriptional profiling to identify the key genes and pathways of pterygium

Purpose

Pterygium results from a variety of biological pathways that are involved in the formation of ocular surface diseases. However, the exact pathogenesis of pterygium is still unclear. Our study focused on gene expression profiles to better understand the potential mechanisms of pterygium.

Methods

RNA sequencing experiments were performed on clinical pterygium tissues and normal conjunctival tissues. To identify the hub genes for the development of pterygium, we further conducted weighted gene co-expression network analysis (WGCNA). qRT-PCR was utilized to validate the dysregulation of the most significant differentially expressed genes (DEGs) and key hub genes in the independent subjects.

Results

A total of 339 DEGs (P-adjusted < 0.05 and log2 fold change [log2FC] ≥ 1.0) were obtained that reached statistical significance with p-values < 0.05. Among them, 200 DEGs were upregulated; these genes were mainly associated with the extracellular matrix and with cell adhesion or migration. In contrast, the 139 downregulated genes were enriched for endocrine and inflammation pathways. With regard to WGCNA, five modules were assigned based on the DEG profiles, and the biological functions of each module were verified with previously published GO terms. The functions included ECM-receptor interactions, the PI3K-Akt signalling pathway and an endoplasmic reticulum (ER)-related pathway. The five hub genes with the highest connectivity in each module and the five most significant DEGs showed dysregulated expression in the independent cohort samples.

Conclusions

RNA sequencing and WGCNA provided novel insights into the potential regulatory mechanisms of pterygium. The identified DEGs and hub genes, which were classified into two groups according to different functions or signalings, may provide important references for further research on the molecular biology of pterygium.

Interferon Alpha-2b Eye Drops Prevent Recurrence of Pterygium After the Bare Sclera Technique: A Single-Center, Sequential, and Controlled Study

To investigate the efficacy and safety of interferon (IFN) alpha-2b eye drops in preventing pterygium recurrence after the bare sclera technique.

Ocular Human Papillomavirus Infections

CONTEXT

- Human papillomavirus (HPV) has a well-known role in the pathogenesis of squamous cell carcinoma and precursor lesions of the cervix, anogenital region, and head and neck, but its role in the development of squamous neoplasms of the eye, particularly the conjunctiva, remains unclear.

OBJECTIVE

- To review recent evidence implicating HPV in the pathophysiology of ocular lesions.

DATA SOURCES

- Published articles obtained from a PubMed search of the English literature were the primary sources for this review.

CONCLUSIONS

- The low-risk HPV types 6 and 11 appear to play a role in the development of at least a subset of conjunctival squamous papillomas. The role of HPV in the pathogenesis of pterygium and ocular surface squamous neoplasia is less well defined. There is evidence to suggest that HPV may be a cofactor in the development of these lesions, acting in concert with ultraviolet radiation and/or human immunodeficiency virus infection in a subgroup of cases.

Bromfenac Inhibits TGF-β1-Induced Fibrotic Effects in Human Pterygium and Conjunctival Fibroblasts

Purpose

Nonsteroidal anti-inflammatory drugs (NSAIDs) have shown antifibrotic effects on several diseases. The aims of the present in vitro study were to investigate the antifibrotic effects of bromfenac (a kind of NSAID) on primary human pterygium fibroblasts (HPFs) and primary human conjunctival fibroblasts (HConFs), as well as to explore the possible mechanisms of these effects.

Methods

The cells used in this study were primary HPFs and HConFs, and profibrotic activation was induced by transforming growth factor-beta1 (TGF-β1). Western blot, quantitative real-time PCR, and immunofluorescence (IF) assays were used to detect the effects of TGF-β1 and bromfenac on the synthesis of fibronectin (FN), type III collagen (COL3), and alpha-smooth muscle actin (α-SMA) in HPFs and HConFs; the changes of signaling pathways were detected by Western blot; cell migration ability was detected by wound healing assay; cell proliferation ability was detected by CCK-8 assay; and pharmaceutical inhibitions of the downstream signaling pathways of TGF-β1 were used to assess their possible associations with the effects of bromfenac.

Results

Bromfenac suppressed the TGF-β1-induced protein expression of FN (0.59 ± 0.07 folds, P = 0.008), COL3 (0.48 ± 0.08 folds, P = 0.001), and α-SMA (0.61 ± 0.03 folds, P = 0.008) in HPFs. Bromfenac also attenuated TGF-β1-induced cell migration (0.30 ± 0.07 folds, P < 0.001), cell proliferation (0.64 ± 0.03 folds, P = 0.002) and the expression levels of p-AKT (0.66 ± 0.08 folds, P = 0.032), p-ERK1/2 (0.69 ± 0.11 folds, P = 0.003), and p-GSK-3β-S9 (0.65 ± 0.10 folds, P = 0.002) in HPFs. PI3K/AKT inhibitor (wortmannin) and MEK/ERK inhibitor (U0126) reduced the TGF-β1-induced synthesis of FN, COL3, and α-SMA in HPFs. All the results were similar in HConFs.

Conclusions

Bromfenac protects against TGF-β1-induced synthesis of FN, α-SMA, and COL3 in HPFs and HConFs at least in part by inactivating the AKT and ERK pathways.

Extracellular matrix and fibroblast injection produces pterygium-like lesion in rabbits

BACKGROUND

Translational research to develop pharmaceutical and surgical treatments for pterygium requires a reliable and easy to produce animal model. Extracellular matrix and fibroblast are important components of pterygium. The aim of this study was to analyze the effect of the subconjunctival injection of fibroblast cells (NIH3T3 cell line) and exogenous extracellular matrix in rabbits in producing a pterygium-like lesion.

METHODS

Six 3-month-old white New Zealand rabbits were injected with 20,000 NIH3T3 cells and 5 µL of Matrigel in the right conjunctiva, and with only 5 µL of Matrigel in the left conjunctiva. The eyes were photographed under a magnification of 16× using a 12-megapixel digital camera attached to the microscope on day 1, 3 and 7. Conjunctival vascularization was measured by analyzing images to measure red pixel saturation. Area of corneal and conjunctival fibrovascular tissue formation on the site of injection was assessed by analyzing the images on day 3 and 7 using area measurement software. Histopathologic characteristics were determined in the rabbit tissues and compared with a human primary pterygium.

RESULTS

The two treatments promoted growth of conjunctival fibrovascular tissue at day 7. The red pixel saturation and area of fibrovascular tissue developed was significantly higher in right eyes (p < 0.05). Tissues from both treatments showed neovascularization in lesser extent to that observed in human pterygium. Acanthosis, stromal inflammation, and edema were found in tissues of both treatments. No elastosis was found in either treatment.

CONCLUSIONS

Matrigel alone or in combination with NIH3T3 cells injected into the rabbits' conjunctiva can promote tissue growth with characteristics of human pterygium, including neovascularization, acanthosis, stromal inflammation, and edema. The combination of Matrigel with NIH3T3 cells seems to have an additive effect on the size and redness of the pterygium-like tissue developed.

Loteprednol etabonate for inflammatory conditions of the anterior segment of the eye: twenty years of clinical experience with a retrometabolically designed corticosteroid

INTRODUCTION

Topical corticosteroids are an important pharmacotherapy for the management of various inflammatory conditions affecting the anterior segment of the eye. However, medications in this class are associated with well-known risks including increased intraocular pressure (IOP) and development of cataracts. The topical corticosteroid loteprednol etabonate (LE) was developed with the specific intention of minimizing these side effects.

AREAS COVERED

The focus of this review is to examine published efficacy and safety data for LE, a drug engineered to undergo rapid metabolism to inactive metabolites with the goal of improved safety. Two decades of clinical research focused on LE formulations are reviewed, including the use of LE in combination with tobramycin. The cumulative body of experience affirms the concept that the molecular design of LE confers certain safety benefits without compromising the desired anti-inflammatory efficacy of a topical corticosteroid.

EXPERT OPINION

Loteprednol etabonate is a mainstay for topical therapy of a wide variety of commonplace and niche conditions of the ocular surface and the anterior segment, including in the healing post-operative patient. Its versatility and safety allow eye care providers to recommend both acute induction as well as chronic maintenance therapy with appropriate follow-up.

Comparison among adjuvant treatments for primary pterygium: a network meta-analysis

PURPOSE

Pterygium is a frequent ocular disease, where the major challenge is the high level of recurrence after its surgical removal. We performed a network meta-analysis to identify, among several adjuvant treatments for primary pterygium, which is the best to prevent recurrence.

METHODS

A search was conducted using PubMed, Scientific Electronic Library Online, Latin American and Caribbean Centre on Health Sciences and Cochrane Eyes and Vision Group Trials Register between 1993 and 2015 for randomisedclinical trials (RCTs) comparing adjuvant treatments following primary pterygium surgery.

RESULTS

24 RCTs that studied 1815 eyes of 1668 patients were included and allowed direct and indirect comparison among 14 interventions through network meta-analysis. The rank from the best to worse treatment to prevent recurrence is: conjunctival autograft + ciclosporin 0.05% eye drops, bare sclera + intraoperativemitomycin C (MMC) <0.02%, bare sclera + beta therapy (2500 cGy single dose), conjunctival autograft + beta therapy (1000 cGy single dose), bare sclera + MMC 0.02% eye drops, conjunctival autograft, bare sclera + intraoperative MMC >0.02%, bare sclera + ciclosporin 0.05% eye drops, bare sclera + intraoperative 5-fluorouracil 5%, amniotic membrane transplantation, bare sclera + intraoperative MMC 0.02%, conjunctival autograft + bevacizumab 0.05% eye drops, bare sclera + bevacizumab 0.05% eye drops and bare sclera alone.

CONCLUSION

The best adjuvant treatment to prevent recurrence after primary pterygium surgery is the association of conjunctival autograft and ciclosporin 0.05% eye drops. Bare sclera technique alone should be discontinued since it is associated with high recurrence rates.

[Pterygium: etiology, pathogenesis, treatment]

Pterygium is a degenerative condition characterized by fibrovascular outgrowth of conjunctiva over the cornea. Many theories exist that try to explain its pathogenesis. The current belief is that this disease is multifactorial with ultraviolet radiation being the most important trigger. Attention is also paid to such factors as tear film changes, cytokines and growth factors disbalance, immunologic disturbances, genetic mutations, and viral infections. Modern classifications consider the rate of fibrovascular growth, its progressive potential, and histological features. In the beginning pterygium is usually asymptomatic, however, dry eye manifestations may be present, such as burning, itching, and/or tearing. As the lesion grows toward the optical zone, visual acuity gets compromised, and thus, surgical treatment is required. Because of recurrences and repeated surgeries, the growth of the lesion may become more aggressive and cause irregular astigmatism. Comprehensive surgery of pterygium is aimed at not only removing the lesion, but also preventing recurrences. Advisable are modified bare sclera techniques with subsequent transposition of the conjunctival flap, conjunctival autotransplantation, amniotic membrane transplantation, and peripheral lamellar keratoplasty (in cases of significant ingrowth). In some cases, antirecurrent adjuvant therapy may be considered that involves the use of mitomycin C, 5-fluoruracil, and VEGF inhibitors. However, the search for the best treatment for pterygium, i.e. an easy to perform, cosmetically-friendly method associated with minimal risk of recurrences and/or complications, remains an interest of modern ophthalmology.

Effect of transverse conjunctival advancement flap surgery for primary pterygium

OBJECTIVE

To introduce a new surgical technique, transverse conjunctival advancement flap, and to evaluate the efficacy and safety of the technique in primary pterygium surgery.

DESIGN

Retrospective, noncomparative, interventional case-series analysis.

PARTICIPANTS

Sixty-three eyes of 63 patients.

METHODS

The patients with primary pterygium were treated with transverse conjunctival advancement flap technique. After excision of the pterygium head and the perilimbal part of the pterygium body (within 2 mm from the limbus), the bare sclera was covered with the transverse conjunctival advancement flap using the conjunctiva of the remaining posterior part of the pterygium body. The patients were followed up for more than 6 months.

RESULTS

The mean age of patients was 64.9 ± 8.7 years (range 43-85 years), and the mean follow-up period was 9.8 ± 3.9 months (range 6-18 months). In all cases, surgery did not exceed 20 minutes. During the follow-up period, recurrence of the pterygium occurred in 1 (1.5%) of the 63 cases, with recurrence only in the conjunctiva. There was no occurrence of serious complications.

CONCLUSIONS

The transverse conjunctival advancement flap technique may be considered a safe and effective method, with a low rate of pterygium recurrence, after primary pterygium excision.

Impact of the Topical Ophthalmic Corticosteroid Loteprednol Etabonate on Intraocular Pressure

Corticosteroids are a mainstay therapeutic option for the treatment of ocular inflammation. However, safety remains a concern for clinicians, particularly with long-term use. Though highly effective at suppressing inflammatory and allergic responses, topical ophthalmic corticosteroids carry an inherent risk of side effects, including elevated intraocular pressure (IOP), a risk factor for the development of glaucoma. The corticosteroid loteprednol etabonate (LE) contains an ester rather than a ketone at the C-20 position, minimizing the potential for side effects, including IOP elevation. In early pivotal clinical trials of LE ophthalmic suspension for conjunctivitis (allergic, giant papillary), anterior uveitis, and post-operative inflammation, LE had minimal impact on IOP over short-term (<28 days) and long-term (≥28 days) use. Since then, new LE formulations—including a gel, an ointment, and a suspension of LE in combination with tobramycin—have become commercially available. Multiple studies evaluating the safety and efficacy of LE for inflammatory conditions have been reported, including those requiring longer-term treatment such as photorefractive keratectomy, corneal transplantation, and dry eye disease. We review the available published data on the effect of LE on IOP and report on the cumulative incidence of clinically significant IOP elevations (≥10 mm Hg from baseline) with short-term and long-term LE use. In all studies, LE consistently demonstrated a low propensity to elevate IOP, regardless of formulation, dosage regimen, or treatment duration, including in known steroid responders. The cumulative proportion of patients exhibiting clinically significant IOP increases was 0.8% (14/1725 subjects) in studies evaluating short-term LE treatment and 1.5% (21/1386 subjects) in long-term studies. Furthermore, use of LE was associated with significantly lower rates of IOP elevation ≥10 mm Hg as compared to prednisolone acetate or dexamethasone (when used in combination with tobramycin). The cumulative data to date substantiates a favorable IOP-safety profile for LE with both short-term and long-term use.

Bare sclera resection followed by mitomycin C and/or autograft limbus conjunctiva in the surgery for pterygium: a Meta-analysis

AIM

To evaluate the recurrence and complications after bare sclera resection (BSR) combined with mitomycin C (MMC) treatment and/or autograft limbus conjunctiva (ALC) in the surgery for pterygium.

METHODS

Meta-analysis was used to evaluate the differences in patient outcomes between BSR of pterygium with or without MMC and/or ALC. All included studies were randomized trials of patients with pterygium who received BSR followed by MMC and/or ALC in the surgery. The recurrence of pterygium and other complications resulting from different treatments were extracted for analysis.

RESULTS

Thirteen studies met the inclusion criteria. The recurrence of pterygium with intraoperative (IO) MMC was higher than that with ALC (OR=2.38, 95% confidence interval 1.45-3.91, I (2)=29%). Postoperative MMC resulted in an incidence of recurrence similar to that of ALC (OR=0.66, 95% confidence interval 0.30-1.42, I (2)=0%), and IO MMC treatment in combination with ALC produced similar patient outcomes to ALC alone (OR=0.41, 95% confidence interval 0.16-1.01, I (2)=16%). Other complications such as punctate epitheliopathy, scleral thinning and ischemia, irritation and persistent epithelium defect, were more common in patients in the MMC group as compared to those treated with ALC.

CONCLUSION

The recurrence of pterygium with BSR followed by ALC is lower than that of BSR followed by MMC, and the incidence of other complications is lower. While ALC is a more effective strategy for treating pterygium, the quality of the ALC transplant should be considered when the patient has a history of glaucoma.