Evaluation of the recurrence rate for pterygium treated with conjunctival autograft

Risk factors for pterygium recurrence based on a retrospective study of 196 patients

Pterygium is considered as important clinical problem due to its special characteristics such as high incidence, multi-factorial disorder and high recurrence rate. The purpose of this study is to identify the postoperative recurrence rate of pterygium and examine the association between systemic inflammation and the type of pterygium and pterygium recurrence. From January 2017 to January 2018, a total of 196 pterygium patients who received surgery were included in this study. Demographic and clinical data were available and extracted from the ongoing clinic records and interviews. Kaplan-Meier analysis was used to evaluate recurrence over time, univariate analysis and logistic regression analysis were applied to identify the variables that may affect the recurrence after pterygium surgery. All enrolled patients were routinely followed up for average of 24.78 ± 6.08 months, among them, 15 patients (7.65%) presented with recurrence following resection surgery. Multivariate analysis showed that recurrence was significantly associated with neutrophil to lymphocyte ratio (NLR) (odds ratio [OR] 4.35, 95% confidence interval [CI], 1.14-16.61, P = 0.03) and pterygium grade (OR: 6.08, 95% CI, 1.52-24.31, P = 0.01) . The postoperative recurrence rate of recurrent pterygium was 7.65%. The preoperative NLR and pterygium grade were significantly associated with recurrence. This study brings potential future benefits to patients selection outcome prediction and improving long-term care strategies.

Effects of ranibizumab on microvasculature, oxidative stress and recurrence in primary pterygium surgery

PURPOSE

To evaluate the effects of pre-operative ranibizumab injection on microvascular density (MVD), 8-hydroxyguanosine (8-OHdG) and recurrence after surgical excision of primary pterygium.

METHOD

This was a prospective cohort interventional study involving 52 patients with primary pterygium divided equally into control and intervention groups. The intervention group received 0.5 mg ranibizumab two weeks prior to pterygium excision surgery. All participants had pterygium excision with autologous conjunctival graft under local anaesthesia. Excised pterygium tissues were evaluated for MVD and 8-OHdG. Each participant was monitored for recurrence up to 2 years after intervention. Pearson chi-square and Fisher exact tests were used to examine the differences between both groups.

RESULTS

The intervention group demonstrated significantly lower MVD (p < 0.001) and recurrence rates (p < 0.001). In the intervention group, 53.8% (n = 14) of patients had MVD 1 + , and 46.2% (n = 12) had MVD 2 + , which was notably lower than the control group, where 53.8% (n = 14) of patients had MVD 3 + and 4 + . No significant difference in 8-OHdG scores was observed between the groups (p = 0.482). In the intervention group, 84.6% (n = 22) of patients had an 8-OHdG score of 3 + , while 76.9% (n = 20) of patients in the control group also had 8-OHdG scores of 3 + . 46.2% (n = 12) of patients from the control group experienced recurrent pterygium, while no cases of pterygium recurrence were observed in the intervention group. Reduction in MVD was significantly associated with lower frequency of pterygium recurrence (p = 0.004).

CONCLUSION

Pre-operative intralesional ranibizumab decreases pterygium recurrence rate after surgical excision via modulation of vascularity. Ranibizumab may be considered as an adjunctive treatment in pterygium surgery with high risk of recurrence.

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.

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.

Characteristics and recurrence of pterygium in Saudi Arabia: a single center study with a long follow-up

Background

This study described the clinical features of patients with pterygium and analyzed the recurrence rate of conjunctival autografting alone, conjunctival autografting combined with intraoperative mitomycin C, and amniotic membrane grafting.

Methods

A retrospective cohort study of primary pterygium was conducted between January 2017 and February 2020. Factors associated with pterygium severity and recurrence were analyzed by univariate analysis and logistic regression models.

Results

The study included 292 patients with an average age of 53.3 ± 14.1 years, while the number of operated cases was 94. Pterygia involving the cornea were observed in 55 % of the cases. The overall rate of recurrence for the three procedures was 17 %. The average time of recurrence was 14.2 ± 11.9 months, with 37 % of the recurrences occurring after the first year. The only factor associated with a significant risk of recurrence was dry eye disease in both univariate (p = 0.021) and multivariate analysis (p = 0.026). The recurrence rates following conjunctival autografting with and without mitomycin C were 15.6 and 15.8 %, respectively. The recurrence rate following the amniotic membrane graft was  twofold (OR= 2.02)  (27 %) that following the conjunctival autograft (15.8 %).

Conclusions

The only factor associated with the recurrence of pterygium was dry eye disease. More than one-third of recurrences developed after the first year, which stresses the importance of a long follow-up. The recurrence rate in our study following conjunctival graft was slightly higher compared to the literature mainly due to differences in study areas, populations, and follow-up periods.

[Antiangiogenic therapy in the surgical treatment of pterygium]

PURPOSE

To evaluate the effectiveness and safety of adjuvant anti-VEGF therapy in the surgical treatment of pterygium, and to determine the indications for its use.

MATERIAL AND METHODS

The study included 67 patients (69 eyes) with grade II-IV pterygium. Patients age was 58.8±12.6 years on average. Best corrected visual acuity (BCVA) varied between 0.01 and 1.0 (0.77±0.24). The patients were divided into 3 groups. The first group included 19 patients (19 eyes) with grade II-III pterygium who underwent «bare sclera» surgery and used aflibercept as adjuvant therapy. The second group included 21 patients (21 eyes) with grade II-IV pterygium who underwent auto conjunctival grafting surgery with no adjuvant therapy. The third group included 27 patients (29 eyes) with grade II-IV pterygium who had it removed in combination with single-time peripheral lamellar keratoplasty (PLK) and underwent adjuvant aflibercept therapy.

RESULTS

Among patients who underwent pterygium excision with adjuvant antiangiogenic therapy there were 5 cases (26%) of relapse during the observation period (23.38±8.96 months), among patients after pterygium excision with auto conjunctival plastic surgery - also 5 cases (24%) of relapse, and among patients who underwent LKP combined with anti-VEGF therapy there was only 1 case (3%) of relapse. Astigmatism has decreased by 0.24±0.5 (p=0.052) in the first group, by 1.21±1.0 (p<0.05) in the second group, and by 1.64±1.54 (p<0.05) in the third group compared with pre-surgical values, thus increasing average BCVA in all 3 patient groups by 0.1±0.13, 0.07±0.11 and 0.15±0.15, respectively.

CONCLUSION

The use of anti-VEGF agents as adjuvant therapy in the surgical treatment of pterygium is a safe method of reducing postoperative inflammation, fibrovascular proliferation and, subsequently, the amount of relapses.

MiR-199a-3p/5p participated in TGF-β and EGF induced EMT by targeting DUSP5/MAP3K11 in pterygium

Background

Recently, it has been reported that miRNA is involved in pterygium, however the exact underlying mechanism in pterygium is unrevealed and require further investigation.

Methods

The differential expression of miRNA in pterygium was profiled using microarray and validated with quantitative real-time polymerase chain reaction (qRT-PCR). Human conjunctival epithelial cells (HCEs) were cultured and treated with transforming growth factor β (TGF-β) and epidermal growth factor (EGF) and transfected with miR-199a-3p/5p mimic and inhibitor. Markers of epithelial-mesenchymal transition (EMT) in HCEs were detected using western blot and immunohistochemistry. Cell migration ability was determined using wound healing and transwell assay, while apoptosis was determined by flow cytometry. The target genes of miR-199a were confirmed by the dual-luciferase reporter assay.

Results

TGF-β and EGF could induced EMT in HCEs and increase miR-199a-3p/5p but suppress target genes, DUSP5 and MAP3K11. With the occurrence of EMT, cell migration ability was enhanced, and apoptosis was impeded. Promoting miR-199a-3p/5p expression could induce EMT in HCEs without TGF-β and EGF, while suppressing miR-199a-3p/5p could inhibit EMT in TGF-β and EGF induced HCEs. In a word, TGF-β and EGF induced EMT could be regulated with miR-199a-3p/5p-DUSP5/MAP3K11 axes. The validated results in tissues showed that, compared with control conjunctival tissues, miR-199a-3p/5p were more overexpressed in pterygium, while DUSP5/MAP3K11 were lower expressed. In addition, bioinformatics analysis indicated the miR-199a-3p/5p-DUSP5/MAP3K11 was belong to MAPK signalling pathway.

Conclusions

TGF-β and EGF induce EMT of HCEs through miR-199a-3p/5p-DUSP5/MAP3K11 axes, which explains the pathogenesis of EMT in pterygium and may provide new targets for pterygium prevention and therapy.

Postoperative treatment compliance rate and complications with two different protocols after pterygium excision and conjunctival autografting

AIM

To evaluate compliance rate to pterygium postoperative treatment with two different protocols.

METHODS

Review of clinical data of patients submitted to pterygium excision and conjunctival autografting in a single centre (and a single surgeon) in Barcelona between March 2014 and December 2017. Initial postoperative protocol (protocol 1) consisted of 4 months of topical steroids in a tapering fashion. Protocol 2 consisted of topical steroids tapered over 5 weeks. Compliance rate, complications and clinical outcomes were evaluated, and statistical comparisons were made.

RESULTS

120 surgeries were performed in 99 patients. Protocol 1 was applied in 63 cases and the next 57 followed protocol 2. Compliance with protocol 1 (57.6%) was lower than with protocol 2 (84.9%) (p = 0.002). Intraoperative complications (graft tear, corneal thinning, corneal perforation and bleeding) were found in 10 cases of protocol 1 and three cases of protocol 2, p = 0.08. Postoperative complications (graft dislocation, graft haematoma, ocular hypertension and recurrence) were found in 31 cases of protocol 1 (46.2%) and eight cases of protocol 2 (14%), p = 0.001. Six weeks after surgery, ocular hypertension was detected in eight cases corresponding to protocol 1 (13.6%) and two cases of protocol 2 (3.8%), p = 0.099. Recurrence rate during first year was higher in protocol 1 (26.3%) compared to protocol 2 (7.6%), p = 0.011. No cases of visual acuity worsening or infection were registered.

CONCLUSION

Protocol 2 has shown to have higher compliance rate than protocol 1 and less postoperative complications, proving to be a safe and effective postoperative treatment after pterygium surgery.

Ologen Implantation versus Conjunctival Autograft Transplantation for Treatment of Pterygium

Purpose

To evaluate the effectiveness and safety of Ologen implantation versus conjunctival autograft transplantation for primary pterygium.

Methods

A retrospective case-series analysis. Thirty-one eyes of 29 patients were included in the Ologen group and 42 eyes of 35 patients in the autograft group. The patients were followed up for 1 year and evaluated for slit-lamp biomicroscopy, intraocular pressure, and adverse events. Recurrence rate, complications, and final appearance of the cases were evaluated prospectively.

Result

At 1 year after operation, 2 eyes recurred (6.5%) in the Ologen group and 4 eyes recurred (9.52%) in the autograft group. There was no statistically significant difference between both groups (P=0.157, χ² = 3.781). There was no occurrence of serious complications. Two eyes among the 31 eyes of the Ologen group were conjunctivitis; the incidence of complications was 6.45% (2 eyes). There was conjunctivitis in 3 eyes of the autograft group, 1 eye complicated with symblepharon, and 1 eye with conjunctival granuloma; the incidence of complications was 11.90% (5 eyes), and there was no statistically significant difference between both groups (P=0.094). The conjuntiva was less vascular and inflamed at 1 month postoperatively in the Ologen group than in the autograft group.

Conclusions

Ologen transplantation was technically easier, provided short operative time compared with conjunctival autograft transplantation, and preserved healthy conjunctiva with less complication and less recurrence; it may be a new, safe, and effective alternative for improving the short-term success rate of primary surgery.

Comparison of hyperdry amniotic membrane transplantation and conjunctival autografting for primary pterygium

Background

The purpose of this study was to evaluate the safety and effectiveness of the hyperdry amniotic membrane transplantation compared with conjunctival autografting for the treatment of primary pterygium.

Methods

One hundred and forty-one eyes from 130 patients with primary pterygium were treated with excision followed by hyperdry amniotic membrane or conjunctival autografting after random selection. Seventy-nine eyes from 71 patients received hyperdry amniotic membrane transplantation (HD-AM group), and 62 eyes from 59 patients received conjunctival autografting (CG group). Patients were followed up at one week and one, three, six, and 12 months post-surgery. Recurrence rate, postoperative complications, and final follow-up patient visits were prospectively evaluated.

Results

The mean follow-up duration was 12.56 ± 4.35 months in the HD-AM group and 12.85 ± 3.90 months in the CG group. Recurrences were detected in four eyes (5.06%) in the HD-AM group and 13 eyes (20.97%) in the CG group. A statistically significant difference in frequency of recurrence between the two groups (P = 0.003) was observed. The cumulative non-recurrence rates at six and 12 months in all patients stratified by age and sex were not significantly different (P = 0.642 and P = 0.451, respectively, by log-rank test). Graft retraction and necrosis were not detected in the two groups during the follow-up period.

Conclusion

Hyperdry amniotic membrane transplantation was effective in preventing pterygium recurrence when compared with conjunctival autografting and can be considered a preferable and safe grafting procedure for primary pterygium.

Trial registration

Current Controlled Trials ISRCTN16900270, Retrospectively registered (Date of registration: 3 May 2018).

Overexpression of low-density lipoprotein receptors stimulated by vascular endothelial growth factor in fibroblasts from pterygium

The activation of subconjunctival fibroblasts is believed to be responsible for the pathogenesis of pterygium. Vascular endothelial growth factor (VEGF) appears to be the most potent stimulator of formation and progression of pterygium. Pterygium excision is a common procedure, although the recurrence rates remain high. Various postoperative adjuvant therapies are now attempted to lower the recurrence rate, with severe side effects. To offer a greater therapeutic effect and lower side effects, it's necessary to discover a constant nanoparticle drug delivery targeting to subconjunctival fibroblasts in pterygium (PSFs). This study was designed to investigate the expression of low-density lipoprotein receptor (LDLr) stimulated by VEGF in PSFs. We found that after exposure to VEGF, mRNA and protein levels of LDLr were both increased significantly in PSFs, assessed using relative quantitative real-time RT-PCR and Western blot. Moreover, it's demonstrated that the expression of LDLr were positively correlated with the cells proliferation. Uptake of DiI-LDL via live PSFs was increased with time, estimated by confocal microscopy. The protein expression of LDLr in pterygium subconjunctival tissues was significantly higher than in normal subconjunctival tissues. These results suggest that LDLr in the activated PSFs may become a novel target receptor for controlled drug delivery to lower postsurgical recurrence rate.

A novel graft option after pterygium excision: platelet-rich fibrin for conjunctivoplasty

PurposeTo compare the surgical results, complications, and recurrence rates of primary pterygium excision with conjunctival autografts (CA) vs platelet-rich fibrin (PRF) grafts.Patients and methodsA total of 35 eyes of 35 patients with primary pterygium were included in the study. The patients underwent excision of pterygium followed by closure of the bare sclera by CA (group 1, n=20) vs PRF grafts (group 2, n=15). The PRF was generated from the patients' own whole-blood sample by centrifugation and pressing. The surgery times, intra/postoperative complications, recurrence rates of pterygium, and changes in visual acuity (VA) were evaluated and compared within groups.ResultsThe mean follow-up period was 14.3±6.5 months (6-24 months). The mean preoperative and postoperative VAs were same (20/25) (P=0.204). The mean surgery time was shorter in group 2 (22.1±1.9 min) compared to group 1 (33.8±7.8 min) (P=0.001). The recurrence was observed only in one (6.6%) case of group 2, while none of the cases showed recurrence in group 1. Graft loss was observed in 2 (10%) cases in group 1, and 1 (6.6%) case in group 2. No other intra/postoperative complications such as tear in the graft, excessive bleeding, scleral necrosis, graft necrosis, pannus formation, or symblepharon occurred in both groups.ConclusionsThis preliminary study showed encouraging results of the application of PRF for conjuntivoplasty after pterygium excision. The use of PRF in pterygium surgery is a simple, easily applicable, and a promising method with low rates of recurrence and complications.

Safety and efficacy of human amniotic membrane in primary pterygium surgery

Grafts made from human amniotic membrane are used to prevent recurrence of pterygium after excision. The success of the procedure can be affected by the quality of preparation and preservation of the grafts. We prospectively evaluated the safety and efficacy of cryopreserved amniotic membrane prepared at the research tissue bank of the Biotechnology Research Center in Tripoli, Libya, and used as adjunct therapy in primary pterygium excision. Twenty-six patients (15 males and 11 females) aged 21-78 years and indicated for primary pterygium excision were transplanted at the Tripoli Eye Hospital with the amniotic membrane grafts. Sixteen patients (62 %) were available for all three follow-up visits scheduled at 1, 3 and 6 months post-surgery. By the third visit, two patients (12.5 %) developed granuloma and three (18.8 %) had pterygium recurrence. The grafts were used after cryopreservation for ≤180 days or >180 days, but statistical analysis showed that the complications were not associated with the length of storage. Moreover, the high rate of complications in this study was not caused by use of cryopreserved AM. In conclusion, locally produced cryopreserved AM is safe as an adjunct therapy for treatment of primary pterygium excision.

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.

Molecular Basis of Pterygium Development

Pterygium pathogenesis is mainly related to UV light exposure. However, the exact mechanisms by which it is formed have not been elucidated. Clinical advances in surgical treatment use conjunctival autografts and amniotic membranes in combination with adjuvant therapies, including mitomycin C, β-radiation, and 5-fluoroacil, to reduce recurrence. Several studies aim to unveil the molecular mechanisms underlying pterygium growth and proliferation. They demonstrate the role of different factors, such as viruses, oxidative stress, DNA methylation, apoptotic and oncogenic proteins, loss of heterozygosity, microsatellite instability, inflammatory mediators, extracellular matrix modulators, lymphangiogenesis, cell epithelial-mesenchymal transition, and alterations in cholesterol metabolism in pterygium development. Understanding the molecular basis of pterygium provides new potential therapeutic targets for its prevention and elimination. This review focuses on providing a broad overview of what is currently known regarding molecular mechanisms of pterygium pathogenesis.

Triple subconjunctival bevacizumab injection for early corneal recurrent pterygium: one-year follow-up

PURPOSE

The aim of the study was to evaluate the effect of 3 subconjunctival bevacizumab injections in patients with an early corneal pterygium recurrence.

METHODS

This study was a nonrandomized single center trial. Patients with an early corneal pterygium recurrence were selected. All patients received 3 subconjunctival bevacizumab (2.5 mg/0.1 mL) injections (basal, 2 and 4 weeks) in the recurrence area of the pterygium. The corneal and corneal-conjunctival neovascularization areas and the corneal opacification area of each pterygium were determined using digital slit lamp pictures.

RESULTS

Thirty-eight patients were enrolled into the study; all patients were injected within 3 months of the diagnosed pterygium recurrence. Interestingly, the bevacizumab injections had a significant effect (P<0.05) on the reduction of corneal, corneal-conjunctival area of neovascularization determined as pixels and on the corneal opacification area determined as mm(2) when comparing the basal values, to the values obtained after 15 days, 1 month, 3 months, 6 months, and 12 months after injections.

CONCLUSIONS

The vascularized area in all recurrent pterygia and the corneal opacification area with this triple regimen of subconjunctival bevacizumab injections were reduced, which remained until the end of the study. These results suggest that bevacizumab subconjunctival injections could be useful to treat recurrent pterygium.