Dual Pathogenesis of Primary and Recurrent Pterygium: Immunohistochemical Proof

Introduction: Pterygium is a common ophthalmic problem in the Middle East where exposures to dust and sun rays are risk factors. The condition is more prevalent in middle-aged males and can be considered as an aging process. The aim of this study is to test both the degenerative and the proliferative components of Pterygium by both reduced glutathione and topoisomerase one activity. Methods: The study applied immunohistochemistry staining for both reduced glutathione and topoisomerase 1. Results: The samples expressed positive glutathione staining in most primary Pterygium conditions and all secondary Pterygium. On the other hand, the topoisomerase 1 immunohistochemistry expressed focal activity in secondary conditions suggesting a progenitor cell role in the pathogenesis of Pterygium in conjunction with oxidative stress. Conclusion: Pterygium represents dual pathology with a proliferative component and a degenerative one that needs further studies. It is possible to use combination immunohistochemistry markers to predict the prognosis of Pterygium behavior.

Surgical treatment of primary and recurrent pterygium

Purpose: to study the results of surgical treatment and the course of healing of primary and recurrent pterygium.Material and methods. 97 patients (117 eyes) with varying degrees of pterygium, of which 58 were men and 39 women, were clinically observed for 1 to 3 years. The patients, aged 51.5 ± 4.2 on average, were divided into 3 groups depending on the degree of pterygium, the frequency of relapses and the type of surgical treatment.Results. It was shown that primary pterygium of the I degree should best be operated according to McReynolds method, pterygium of the II degree or higher should optimally be removed with conjunctival plastics by a free flap grafting, while for recurrent pterygium of the III degree or higher, combined treatment is recommended: removal of the pterygium using brachytherapy.Conclusion. For an adequate functional result of surgery, an individual approach is required for each case depending on pterygium proliferation stage.

New approach to surgical treatment of primary progressive pterygium

Purpose. To evaluate effectiveness of new method of barrier amnioplasty in surgical treatment of primary progressive pterygium. Material and methods. The study included 64 patients (64 eyes) with primary progressive pterygium. All patients were divided into two groups depending on method of barrier amnioplasty. The main group consisted of 32 people (32 eyes) who underwent barrier amnioplasty in the area of initial growth of pterygium. The control group consisted of 32 patients (32 eyes) who underwent barrier amnioplasty in the limbus area. The main criterions for clinical efficacy of surgical treatment of pterygium was dynamics of the wound process, the Ocular Surface Disease Index (OSDI) and the osmolarity of the tear fluid in the compared groups. Also, after 1 year, the frequency of pterygium recurrence was assessed. In addition to standard ophthalmological examinations, special methods were used in the work: determination of the osmolarity of the tear fluid, pH of tears, cytological assessment of the wound process, and also assessed the OSDI. Results. The results of pH-metric, osmometric, cytological studies have provided evidence of the ability of the anatomical and topographic approach described by us to positively influence the course of inflammatory and reparative processes in the operation area, preventing the development of recurrent pterygium and cicatricial deformities. Conclusion. A new effective method of surgical treatment of primary progressive pterygium, including moving the area of the barrier amnioplasty from the limbus area to the area of initial growth of blood vessels of pterygium - the area of the lunate fold, has been developed and introduced into clinical practice. Key words: pterygium, inflammatory and reparative processes, recurrence.

Effects of Preoperative Versus Intraoperative Application of Mitomycin C on the Outcome of Pterygium Surgery: A Meta-Analysis

Background: The use of mitomycin C (MMC) has been recommended to reduce postoperative recurrence in patients undergoing pterygium surgery. However, the outcomes with preoperative (PO) and intraoperative (IO) application of mitomycin C have not been adequately compared. Objective: This study aimed to evaluate PO MMC versus IO MMC in terms of recurrence and complications for pterygium treatment. Methods: PubMed, EMBASE, and Cochrane Library were systematically searched with the keywords “pterygium,” “mitomycin,” and “preoperative” and “intraoperative.” Randomized controlled trials (RCTs) comparing PO MMC with IO MMC in pterygium surgery were included. A risk of bias tool was used to perform qualitative assessments. Outcome measurements were recurrence and complications of the ocular surface. Review Manager 5.3 was used for statistical analysis. Results: Five RCTs with 390 participants (390 eyes) showing primary or recurrent pterygium were included. Recurrence of pterygium with PO MMC was similar to that with IO MMC (RR = 1.04, 95% CI, 0.61 to 1.76, P = 0.89). There was no significant difference between the two treatments (PO MMC vs. IO MMC) with respect to complications of the ocular surface, including conjunctival complications (RR = 1.04; 95% CI, 0.61 to 1.76; P = 0.89), scleral complications (RR = 0.72; 95% CI, 0.14 to 3.73; P = 0.70), and corneal complications (RR = 1.33; 95% CI, 0.32 to 5.48; P = 0.70). Conclusion: PO MMC was as efficient as IO MMC in controlling the recurrence and complications in pterygium surgery.

Recurrent pterygium in Bintulu, Sarawak (Malaysian Borneo): determining its risk factors

Introduction: Pterygium may give rise to astigmatism in addition to causing blindness in advanced stages, reflecting the importance of timely surgical intervention. Despite various operative approaches, the recurrence rate continues to range from 2% to 89%. Therefore, it is essential to investigate the risk factors influencing recurrence to improve therapeutic strategies. Purpose: To determine the risk factors of pterygium recurrence among the multiethnic cohort of patients in Bintulu, Sarawak (Malaysian Borneo). Study design: Retrospective cohort. Materials and methods: This study was conducted in Bintulu Hospital, Sarawak and involved patients who underwent pterygium excision with conjunctival autografting between April 1, 2016 and May 31, 2019. Patients completed at least a year of follow-up for recurrence detection. Collected data included presence of recurrence, sociodemographics, outdoor activities, habits, first-degree family history, pterygium type and location, as well as laterality. Chi-squared test, Fisher’s exact test, and logistic regression analysis were used. Results: A total of 161 eyes that underwent pterygium excision in 137 patients were identified. Percentage of recurrence was 42%. Mean age during excision was 59.3 ± 11.5 years; age group showed no significance in pterygium recurrence (p = 0.447). Male gender showed statistical significance (p = 0.045, OR 1.90, CI 1.01, 3.58) in chi-squared test but not in logistic regression. Ethnicity, marital status, income, and education level showed no association with recurrence (p > 0.05). Anatomic factors like location (p = 0.353) and laterality (p = 0.955) also showed no association. Smoking (p = 0.867) and alcohol intake (p = 0.397) were insignificant, similar to first-degree family history (p = 0.137). Activities involving sun exposure (p < 0.001, OR 18.34, 95% CI 5.59, 60.17) and recurrent pterygium type (p = 0.001, OR 7.40, 95% CI 1.81, 30.21) supported a positive association with recurrence. Medication adherence (p < 0.001, OR 3.61, 95% CI 1.07, 12.21) and the use of sun protection (p < 0.001, OR 7.90, 95% CI 3.25, 19.19) showed a statistically significant decrease in recurrence. Conclusion: Activities involving sun exposure, use of sun protection, medication adherence, and recurrent pterygium type have shown to be statistically significant in influencing pterygium recurrence.

Expression and role of specificity protein 1 and collagen I in recurrent pterygial tissues

AIM: To investigate the expression profiles of the transcription factor specificity protein 1 (Sp1) and collagen I in recurrent pterygial tissues. What is more, to compare the changes of Sp1 and collagen I among primary pterygial tissue, recurrent pterygial tissue and conjunctival tissue. METHODS: In the prospective study, we collected the pterygial tissues of 40 patients who underwent resection of primary pterygial tissue and recurrent pterygial tissue, and the conjunctival tissues of 10 patients with enucleation due to trauma. The relative expression levels of Sp1 and collagen I were analyzed by reverse transcription quantitative-polymerase chain reaction and Western blot. Paired t-test was performed to compare the Sp1 and collagen I of recurrent pterygial tissues, as well as the primary pterygial tissues and conjunctival tissues. In further, Pearson’s hypothesis testing of correlation coefficients was used to compare the correlations of Sp1 and Collagen I. RESULTS: The content of Sp1 and collagen I mRNA and protein was significantly greater in recurrent pterygial tissue than that was in primary and conjunctival tissue (P<0.05). There was a positive correlation between the mRNA and protein levels of Sp1 and collagen I in recurrent pterygial tissues (protein: r=0.913, P<0.05; mRNA: r=0.945, P<0.05). CONCLUSION: Sp1 and collagen I are expressed in normal conjunctival, primary, and recurrent pterygial tissues, but expression is significantly greater in the latter. Sp1 and collagen I may be involved in the regulation of the development of recurrent pterygium.

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.