-
Eye (London, England) Jun 2020Pterygia are common conjunctival degenerations with well-documented risk factors but an unclear pathogenesis. Better understanding of the pathogenesis of pterygium could... (Review)
Review
Pterygia are common conjunctival degenerations with well-documented risk factors but an unclear pathogenesis. Better understanding of the pathogenesis of pterygium could lead to improved surgical outcomes and decreased postoperative recurrence. Currently, pterygium excision with conjunctival autograft remains the preferred surgical technique to decrease pterygium recurrence. Many adjuvant therapies have been used in pterygium surgery to varying degrees of success. Topical cyclosporine, an immunosuppressive medication, in conjunction with conjunctival autograft was found to be most successful in decreasing pterygium recurrence according to a recent meta-analysis. Other adjuvant therapies such as mitomycin-C (MMC), 5-fluorouracil (5-FU), and beta-irradiation have also been used, though usage of these may cause multiple adverse effects. Recent research indicates that interactions between mouse double minute 2 (MDM2) and p53 could play a role in the occurrence of pterygium. Nutlin, an MDM2 antagonist, was found to have significantly less toxicity in conjunctival cells when compared with MMC on laboratory analysis of pterygium samples.
Topics: Animals; Conjunctiva; Follow-Up Studies; Mice; Mitomycin; Ophthalmologic Surgical Procedures; Pterygium; Recurrence; Transplantation, Autologous
PubMed: 32029918
DOI: 10.1038/s41433-020-0786-3 -
Ophthalmic Research 2022Pterygium is a kind of common conjunctival degeneration. The pathogenesis of pterygium is complex, and various biomarkers provide new targets for treatment and... (Review)
Review
Pterygium is a kind of common conjunctival degeneration. The pathogenesis of pterygium is complex, and various biomarkers provide new targets for treatment and prognosis. Currently, the most common treatment for pterygium is surgical excision, but it is invasive risk and has a high recurrence rate. Since the development of sequencing, gene chip technology, and proteomics technologies has been rapid, research on the internal mechanism of disease has been facilitated. This review focuses on recent advances in the discovery of biomarkers from the fields of genetics, proteomics, and epigenetics and their likely functional mechanisms and clinical applications in pterygium.
Topics: Biomarkers; Conjunctiva; Follow-Up Studies; Humans; Pterygium; Recurrence; Transplantation, Autologous
PubMed: 35405677
DOI: 10.1159/000523878 -
Journal of Population Therapeutics and... 2022Pterygium is a bulbar conjunctival fibrovascular growth that crosses the limbus and extends onto the peripheral cornea, and in some cases leads to significant visual... (Review)
Review
Pterygium is a bulbar conjunctival fibrovascular growth that crosses the limbus and extends onto the peripheral cornea, and in some cases leads to significant visual complications. The prevalence of this disease has been reported to be from 1.2% to about 40% in different parts of the world. Although there are various risk factors for pterygium, which include ultraviolet (UV) radiation, viral infection, hereditary factors, immune factors, aseptic inflammation, and environmental irritation, the pathogenesis of pterygium is mainly related to exposure to UV light. In addition to cosmetic problems, pterygium can lead to eye irritation, disrupt the transparency of cornea on the pupil area, and cause disorders such as corneal astigmatism and damage to the visual axis leading to vision impairment. In the last few years, the treatment of pterygium has been developed and various new solutions have been used. Surgery is the main treatment for pterygium. Various techniques such as Bare Sclera, Rotational Conjunctival Flap, Limbal Conjunctival Autograft, Amniotic Membrane Graft, and Free Conjunctival Autograft are used for the removal of pterygium. It also seems that the worrisome problem of recurrence has been significantly reduced with newer treatment methods. On the contrary, the use of auxiliary treatments such as mitomycin C, b-radiation, 5-fluorouracil, topical use of interferons, and Avastin are also effective in reducing the recurrence rate.
Topics: Humans; Pterygium; Recurrence; Conjunctiva; Mitomycin; Transplantation, Autologous; Treatment Outcome; Follow-Up Studies
PubMed: 36371649
DOI: 10.47750/jptcp.2022.968 -
Vestnik Oftalmologii 2017Pterygium is a degenerative condition characterized by fibrovascular outgrowth of conjunctiva over the cornea. Many theories exist that try to explain its pathogenesis.... (Review)
Review
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.
Topics: Disease Management; Humans; Pterygium
PubMed: 29165417
DOI: 10.17116/oftalma2017133576-83 -
Eye (London, England) 1989This paper reviews the histological and epidemiological characteristics of pterygium which suggest that chronic exposure to ultraviolet radiation plays an important role... (Review)
Review
This paper reviews the histological and epidemiological characteristics of pterygium which suggest that chronic exposure to ultraviolet radiation plays an important role in the pathogenesis of this disorder. However, there is conflicting evidence indicating that chronic inflammation from other causes can induce the disease. The results of two epidemiological surveys undertaken in Southern Africa show that pterygium is not closely linked to other chronic actinic disorders such as pinguecula and climatic droplet keratopathy. Pterygia differ from these disorders by their vascularity which is probably induced by chronic inflammation. On histological examination, we found that excised pterygia contained a lymphocytic infiltration consisting predominantly of T cells. In the pathogenesis of pterygium we believe that chronic irritation (from whatever cause) produces a chronic inflammatory cell infiltration with resultant inflammatory oedema, attempt at repair and cell induced angiogenesis. These processes, together with actinic damage, are responsible for the fibrovascular reaction so characteristic of a growing pterygium.
Topics: Adolescent; Adult; Africa, Southern; Aged; Child; Conjunctival Diseases; Corneal Diseases; Female; Humans; Male; Middle Aged; Prevalence; Pterygium; Ultraviolet Rays
PubMed: 2695353
DOI: 10.1038/eye.1989.31 -
Nigerian Journal of Clinical Practice Aug 2021To determine the pattern and risk factors of pterygium in adults at the Guinness Eye Centre Onitsha, Nigeria.
OBJECTIVE
To determine the pattern and risk factors of pterygium in adults at the Guinness Eye Centre Onitsha, Nigeria.
MATERIALS AND METHODS
Consecutive adults aged ≥30 years with pterygium were studied. Each patient had comprehensive ocular examination including visual acuity, anterior segment, and adnexal assessment and fundoscopy. The pterygium was graded in terms of severity and type.
RESULTS
A total of 156 patients with pterygium participated; 92 (59%) females versus 64 (41%) males (F:M =3:2). The age range was 30-65 years; mean: 43.9 ± 8.4 years. The majority of the study population (36.5%) was of the age group 40-49 years. The subjects were predominately traders 78 (50%) and 93 (59.6%) of the pterygium patients were outdoor workers. Bivariate analysis indicated that those involved in outdoor work were six times at greater risk of developing pterygium than indoor workers (P = 0.001; OR = 6.2). Out of the 156 pterygium patients seen, 107 (68.6%) of them complained of associated symptoms. Redness of the eye was the commonest symptom reported by 79 (50.9%) cases while 8 (5.1%) cases complained of burning sensation. There was a preponderance of nasal pterygia with temporal pterygia being the least. Blinding pterygium was seen in three eyes (1.3%).
CONCLUSION
Pterygium is a common disorder presenting at eye clinics. Outdoor workers are at a greater risk of developing pterygium. Thus, health education is of great importance.
Topics: Adult; Aged; Conjunctiva; Female; Humans; Male; Middle Aged; Nigeria; Pterygium; Risk Factors; Visual Acuity
PubMed: 34397032
DOI: 10.4103/njcp.njcp_89_21 -
Arquivos Brasileiros de Oftalmologia 2019Pterygium pathogenesis has been mainly asso ciated with UV light exposure; however, this association remains quite controversial. The complete mechanism of pterygium... (Review)
Review
Pterygium pathogenesis has been mainly asso ciated with UV light exposure; however, this association remains quite controversial. The complete mechanism of pterygium also remains to be clarified. Factors such as inflammation, viral infection, oxidative stress, DNA methylation, inflammatory mediators, extracellular matrix modulators, apoptotic and oncogenic proteins, loss of heterozygosity, microsatellite instability, lymphangiogenesis, epithelial-mesenchymal cell transition, and alterations in cholesterol metabolism have been identified as causes. Several studies aimed to clarify the molecular mechanisms underlying the growth and proliferation of pterygium. Understanding its molecular basis provides new potential therapeutic targets for its prevention and treatment. A comprehensive search of the databases, namely, MedLine, EMBASE, and LILACS, was conducted with the following key words: pterygium, epidemiology, pathogenesis, biomarkers, and review. This review describes the epidemiology, clinical presentation, and current investigation of biological mediators involved in pterygium development.
Topics: Apoptosis Regulatory Proteins; Extracellular Matrix; Female; Gene Expression; Genes, Tumor Suppressor; Genetic Markers; Humans; Male; Pterygium
PubMed: 31576927
DOI: 10.5935/0004-2749.20190103 -
Drug Discovery Today Jan 2023Pterygium is a fibrovascular tissue growth invading the cornea. Adjunctive treatment post-surgery includes conventional immunosuppressants as well as antiviral drugs.... (Review)
Review
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.
Topics: Humans; Pterygium; Biological Products; Conjunctiva; Cornea
PubMed: 36280041
DOI: 10.1016/j.drudis.2022.103416 -
Australian and New Zealand Journal of... Nov 1998
Review
Topics: Chemotherapy, Adjuvant; Costs and Cost Analysis; Humans; Ophthalmologic Surgical Procedures; Pterygium; Radiotherapy, Adjuvant; Risk Assessment
PubMed: 9843252
DOI: 10.1111/j.1442-9071.1998.tb01328.x -
Journal of Cellular Physiology Aug 2019Pterygium as a complex disease shares common features with other malignant cells in its onset recurrence and especially epithelial-mesenchymal transition (EMT)... (Review)
Review
Pterygium as a complex disease shares common features with other malignant cells in its onset recurrence and especially epithelial-mesenchymal transition (EMT) transition. Although using different approaches including conjunctival autografts, amniotic membrane, radiotherapy, mitomycin C (MMC) has shown promising insights in the inhibition of pterygium recurrence, it needs to be investigated in more details in molecular pathways to present adjuvant target therapy. In this study, we aimed to evaluate the expression of and then illustrate the role of signaling pathways on EMT in pterygium. Using real-time polymerase chain reaction, the twist-related protein 1 (TWIST1) expression was compared in primary pterygium and normal conjunctiva. This study assessed the mRNA expression, as well as the association between the clinicopathological indices and the gene expression level. The expression level of TWIST1 was overexpressed in 36% of our cohort ( n = 76). There was a significant positive correlation between recurrence with grade T, grade V and a significant negative correlation with growth activity. Our vast literature review on different signaling pathways in pterygium showed that EMT has centralization role in recurrence of this disease. Our data confirmed that EMT is important in the recurrence of pterygium samples and different signaling pathways end up activating the EMT markers. It is suggested to evaluate the environmental factors and their correlation with molecular markers to select favorable treatment for this kind of diseases.
Topics: Adult; Case-Control Studies; Conjunctiva; Epithelial-Mesenchymal Transition; Female; Humans; Male; Nuclear Proteins; Pterygium; Recurrence; Severity of Illness Index; Signal Transduction; Twist-Related Protein 1; Up-Regulation
PubMed: 30847945
DOI: 10.1002/jcp.28447