Current and Future Techniques in Wound Healing Modulation after Glaucoma Filtering Surgeries

A modified trabeculectomy technique with direct filtration into the Tenon's capsule

OBJECTIVE

To report the surgical outcomes of a modified trabeculectomy technique involving implanting the Tenon's layer under the scleral flap.

DESIGN

Prospective, interventional case series.

PARTICIPANTS

51 eyes with medically uncontrolled glaucoma were enrolled for this study. A new trabeculectomy technique, the Tenon's filtration technique for trabeculectomy (TFT-LEC) was used in 26 eyes, while a conventional procedure, normal trabeculectomy (N-LEC), was used for 25 eyes.

METHODS

Intraocular pressure (IOP) control, the number of glaucoma medications, the need for additional interventions, and postoperative complications were assessed.

RESULTS

Twelve months postoperatively, the mean IOP was 13.5 ± 0.5 mmHg in the TFT-LEC group and 15.4 ± 0.5 mmHg in the N-LEC group (p = 0.13). The TFT-LEC group required an average of 1.3 ± 1.0 additional glaucoma medications (21 cases required only ripasudil) postoperatively, with no cases of bleb needling revision or reoperation. The N-LEC group required an average of 1.7 ± 1.5 glaucoma medications (p = 0.43) compared to TFT-LEC group, eight cases (32%) required bleb needling revision (p = 0.002), and one case (4%) of reoperation (p = 0.49). The complications in the TFT-LEC group included shallow anterior chamber in six (23 %) cases (p = 1.00) compared to N-LEC group, choroidal detachment in two (8%) cases (p = 0.42), and anterior chamber hemorrhage in seven (27%) cases (p = 0.29). None of these complications affected visual function.

CONCLUSIONS

This new technique involving implanting the Tenon's layer under the scleral flap may improve the postoperative outcomes of trabeculectomy.

Five-year outcomes of trabeculo-canalectomy for Chinese PACG patients: a retrospective study

BACKGROUND

To evaluate the 5-year outcomes of trabeculo-canalectomy in the treatment of primary angle-closure glaucoma (PACG) among Chinese patients.

METHODS

A retrospective study was designed, involving 46 PACG patients (50 eyes) treated with trabeculo-canalectomy at the First Affiliated Hospital of Nanjing Medical University from January 2016 to December 2018. The patients were followed up at 1 week, 1 month, 3 months, 6 months, 12 months, 1 year, 2 years and 5 years. Surgical success was defined as intraocular pressure (IOP) ≤ 21 mmHg (1 mmHg = 0.133 kPa) under glaucoma medication (qualified success) and without any glaucoma medication (absolute success). Main outcomes were measured according to IOP, number of medication regimens, surgical success rate, complications, and filtering bleb status.

RESULTS

A total of 46 PACG patients (50 eyes) were finally included for statistical analysis, with a mean age of 56.68 ± 6.75 years (range, 41-69 years). The mean preoperative IOP was 30.72 ± 10.26 mmHg with a median number of medication regimens of 2 (range, 0 to 4). Compared to those before the operation, the mean IOP decreased to 12.15 ± 3.11, 14.33 ± 4.10, 15.68 ± 4.24, 16.45 ± 4.14, 16.95 ± 3.51, 17.67 ± 3.15 and 17.04 ± 3.78 mmHg at 1 week, 1 month, 3 months, 6 months, 12 months, 1 year, 2 years and 5 years, respectively. The median (range) numbers of medication regimens were 0 (0 ~ 1), 0 (0 ~ 2), 0 (0 ~ 2), 0 (0 ~ 2), 0 (0 ~ 2), 0 (0 ~ 3), 0 (0 ~ 3), 0 (0 ~ 3) at the eight time points, respectively. The mean postoperative IOP and the number of medication regimens at each time point were significantly lower than those before operation (all P < 0.01). The 5-year total success rate was 89%, and the absolute success rate was 78%. Shallow anterior chamber (10%) and hyphema (12%) were the most common complications early after surgery. At 3 months, anterior segment slit-lamp photography and ultrasound biomicroscopy showed no obvious filtering blebs in 50 eyes (100%). IOP increased transiently in 6 eyes (12%) within 1 month after surgery.

CONCLUSION

Simple and cost-saving trabeculo-canalectomy provides favorable 5-year outcomes in the treatment of medically uncontrolled PACG, as shown by more effective IOP control, more obvious drug reduction, as well as fewer post-operative interventions compared to trabeculectomy.

Vision-related quality of life in patients with glaucoma before and after trabeculectomy

PURPOSE

To determine vision-related quality of life (VR-QoL) and functional and structural parameters associated with VR-QoL in patients with glaucoma before and 12 months after trabeculectomy.

METHODS

Fifty-eight patients undergoing trabeculectomy were included. Participants completed the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) prior to and 12 months after trabeculectomy. Functional (visual acuity and visual fields) and structural (ganglion cell layer volume) parameters were evaluated for their association with VR-QoL using multiple linear regression of VFQ-25 subscale scores. Intraocular pressure and the number of glaucoma medications were also included in the analyses.

RESULTS

The VFQ-25 composite score did not change after trabeculectomy (before: 74.9; 12 months: 74.0; p = 0.512). The subscale mental health had a significantly higher score 12 months after trabeculectomy (before: 65.6; 12 months: 71.4; p = 0.017). The VFQ-25 scores for general health (before: 68.5; 12 months: 62.5; p = 0.009) and role difficulties (before: 78.9; 12 months: 53.7; p < 0.001) were significantly lower 12 months after trabeculectomy. No functional or structural parameters were associated with VFQ-25 composite score.

CONCLUSION

Overall, VR-QoL in glaucoma patients was similar before and after trabeculectomy, reflecting the procedure's stabilizing effect on both objective and subjective visual function. The absence of correlations between VR-QoL and clinical parameters emphasizes the multifaceted nature of VR-QoL and highlights the limitations of depending solely on objective clinical metrics to evaluate patients' subjective experiences. Using both objective measures and VR-QoL, clinicians can better understand the challenges patients face due to glaucoma and trabeculectomy, potentially leading to better solutions.

Wound Modulations in Glaucoma Surgery: A Systematic Review

Excessive fibrosis and resultant poor control of intraocular pressure (IOP) reduce the efficacy of glaucoma surgeries. Historically, corticosteroids and anti-fibrotic agents, such as mitomycin C (MMC) and 5-fluorouracil (5-FU), have been used to mitigate post-surgical fibrosis, but these have unpredictable outcomes. Therefore, there is a need to develop novel treatments which provide increased effectiveness and specificity. This review aims to provide insight into the pathophysiology behind wound healing in glaucoma surgery, as well as the current and promising future wound healing agents that are less toxic and may provide better IOP control.

Steroids and/or Non-Steroidal Anti-Inflammatory Drugs as Postoperative Treatment after Trabeculectomy-12-Month Results of a Randomized Controlled Trial

This prospective randomized controlled trial aimed to compare the efficacy and safety of topical preservative-free diclofenac (DICLO) to dexamethasone (DEX) eyedrops, and their combination (DEX+DICLO) after trabeculectomy. Sixty-nine patients with medically uncontrolled glaucoma were randomized to receive topical postoperative treatment with DICLO (n = 23), DEX (n = 23), or a combination of DEX and DICLO (n = 23). The primary outcome was the intraocular pressure (IOP) 12 months postoperatively. Secondary outcomes included surgical success, failure, visual field, and visual acuity from baseline to 12 months postoperatively. IOP reached the lowest point one day after trabeculectomy. At 12 months, IOP was 10.0 mmHg (95% CI, 8.4-11.6 mmHg) for DICLO, 10.9 mmHg (95% CI, 9.4-12.3 mmHg) for DEX, and 11.2 mmHg (95% CI, 9.1-13.3 mmHg) for DEX+DICLO. There were no significant differences in IOP, surgical success, failure, visual field, or visual acuity between the DICLO, DEX, or DEX+DICLO groups. We found that topical diclofenac was not statistically different from topical dexamethasone in controlling IOP 12 months after trabeculectomy. Combining diclofenac and dexamethasone offered no added IOP control compared to dexamethasone alone.

Clinical value of anterior segment optical coherence tomography‑assisted Wuerzburg bleb classification system for bleb assessment following trabeculectomy

The Wuerzburg bleb classification system (WBCS) is an established tool for evaluating filtering blebs, while anterior segment optical coherence tomography (ASOCT) provides detailed information on inner bleb structure. The present study aimed to investigate the clinical value of ASOCT-assisted WBCS following trabeculectomy (TRAB). The present prospective, observational study included eyes that underwent TRAB. Bleb assessments using the WBCS were based on the image acquired by ASOCT. The WBCS scores were assessed at postoperative week 2 and postoperative month (POM) 1, 2, 3, 6 and 12. The surgical outcomes at 1 year were determined as success or failure. Spearman's analysis explored the correlation of WBCS scores with intraocular pressure (IOP) and surgical outcome. A total of 32 eyes from 32 patients were included in the present study. The WBCS total score significantly correlated with IOP at POM 1, 2, 3, 6 and 12 (P<0.05). For single parameters, microcysts demonstrated a good correlation with IOP at POM 1, 2, 3, 6 and 12 (P<0.05). The WBCS total score correlated well with surgical outcome at POM 2, 3, 6 and 12 (P≤0.005). Microcysts, vascularity and encapsulation significantly correlated with surgical outcomes (P<0.05). The results of the present study suggest that ASOCT-assisted WBCS is a simple and effective measurement system for blebs after TRAB in clinical practice, which correlates well with IOP and surgical outcomes. Blebs with a higher WBCS total score and microcysts score in the early postoperative period, such as at POM 2 and 3, are less likely to have surgical failure in the long term.

Phaco-goniosynechialysis versus phaco-trabeculectomy in patients with refractory primary angle-closure glaucoma: a comparative study

PURPOSE

To compare the effects of phacoemulsification with intraocular lens implantation (phaco) combined with goniosynechialysis (phaco + GSL) versus phaco with trabeculectomy (phaco + trab) for the management of primary angle-closure glaucoma (PACG) refractory to peripheral anterior synechiae (PAS) of over 180°.

METHODS

This retrospective study followed 77 eyes of 77 patients for at least 6 months. Intraocular pressure (IOP), best-corrected visual acuity (BCVA), number of glaucoma drugs, and PAS were recorded at the preoperative baseline and evaluated at each postoperative follow-up visit. The National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25) was administered to patients enrolled in this study. Pearson's correlation analysis and multivariate linear analysis were performed to identify factors influencing changes in NEI VFQ-25 scores and to identify factors associated with increases in NEI VFQ-25 scores after the operation.

RESULTS

In total, seventy-seven eyes were included (43 with phaco + GSL and 34 with phaco + trab). Comparing preoperative baseline and month 6 after surgery measurements revealed that both groups found significant improvements in IOP, PAS, BCVA and the number of glaucoma drugs (P < 0.05). Baseline NEI VFQ-25 scores were similar in the two groups, but there was a significant difference in postoperative NEI VFQ-25 scores (74.47 ± 10.39 in phaco + GSL vs. 69.57 ± 8.54 in phaco + trab, P = 0.048 < 0.05), and the phaco + GSL group had better scores at the time of the last follow-up. The change in preoperative scores and the number of glaucoma drugs was significantly correlated with postoperative scores in the phaco + GSL group.

CONCLUSION

Phaco + GSL treatment is as safe and effective as phaco + trab for refractory PACG patients, and patients' subjective experience improved significantly after phaco + GSL surgery.

Early Inflammation Control After Trabeculectomy by Steroid and Non-steroidal Eye Drops: A Randomized Controlled Trial

INTRODUCTION

To compare the effect of three different anti-inflammatory regimens consisting of preservative-free dexamethasone (DEX), diclofenac (DICLO) eye drops, and their combination (DEX + DICLO) following trabeculectomy on early postoperative inflammation.

METHODS

A prospective randomized controlled trial. Sixty-nine patients undergoing trabeculectomy were randomized to receive either postoperative treatment with topical DEX (n = 23), topical DICLO (n = 23), or a combination of topical DEX and topical DICLO (n = 23) after trabeculectomy. The primary outcome was the anterior chamber flare measurement in the first 3 months postoperatively. Secondary outcomes included intraocular pressure, central corneal thickness, conjunctival injection, and number of cells in the anterior chamber from baseline to 3 months postoperatively.

RESULTS

Anterior chamber flare reached a maximum 1 day after trabeculectomy with an increase of 55% (95% CI 37-73%) for DEX, 64% (95% CI 47-82%) for DICLO, and 57% (95% CI 39-75%) for DEX + DICLO and returned to near pre-operative values 6 weeks after surgery. There were no significant differences in anterior chamber flare [effect size for DICLO: 0.16 (95% CI - 4.3 to 4.6), effect size for DEX + DICLO: 0.09 (95% CI - 4.1 to 4.3)], intraocular pressure, central corneal thickness, conjunctival injection, or number of cells in the anterior chamber between DEX, DICLO, or DEX + DICLO groups.

CONCLUSION

We found that topical diclofenac was not statistically different from topical dexamethasone in controlling early postoperative inflammation after trabeculectomy, while combining diclofenac and dexamethasone offered no added anti-inflammatory control compared to dexamethasone alone.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov (NCT04054830).

Local Drug Delivery Strategies towards Wound Healing

A particular biological process known as wound healing is connected to the overall phenomena of growth and tissue regeneration. Several cellular and matrix elements work together to restore the integrity of injured tissue. The goal of the present review paper focused on the physiology of wound healing, medications used to treat wound healing, and local drug delivery systems for possible skin wound therapy. The capacity of the skin to heal a wound is the result of a highly intricate process that involves several different processes, such as vascular response, blood coagulation, fibrin network creation, re-epithelialisation, collagen maturation, and connective tissue remodelling. Wound healing may be controlled with topical antiseptics, topical antibiotics, herbal remedies, and cellular initiators. In order to effectively eradicate infections and shorten the healing process, contemporary antimicrobial treatments that include antibiotics or antiseptics must be investigated. A variety of delivery systems were described, including innovative delivery systems, hydrogels, microspheres, gold and silver nanoparticles, vesicles, emulsifying systems, nanofibres, artificial dressings, three-dimensional printed skin replacements, dendrimers and carbon nanotubes. It may be inferred that enhanced local delivery methods might be used to provide wound healing agents for faster healing of skin wounds.

PLA-PEG Implant as a Drug Delivery System in Glaucoma Surgery: Experimental Study

Excessive postoperative scarring halts the effectiveness of glaucoma surgery and still remains a challenging problem. The purpose of this study was to develop a PLA-PEG-based drug delivery system with cyclosporine A or everolimus for wound healing modulation. Methods: PLA-PEG implants saturation with cyclosporine A or everolimus as well as their further in vitro release were analyzed. Anti-proliferative activity and cytotoxicity of the immunosuppressants were studied in vitro using human Tenon’s fibroblasts. Thirty-six rabbits underwent glaucoma filtration surgery with the application of sham implants or samples saturated with cyclosporine A or everolimus. The follow-up period was six months. A morphological study of the surgery area was also performed at seven days, one, and six months post-op. Results: PLA-PEG implants revealed a satisfactory ability to cumulate either cyclosporine A or everolimus. The most continuous period of cyclosporine A and everolimus desorption was 7 and 13 days, respectively. Immunosuppressants demonstrated marked anti-proliferative effect regarding human Tenon’s fibroblasts without signs of cytotoxicity at concentrations provided by the implants. Application of PLA-PEG implants saturated with immunosuppressants improved in vivo glaucoma surgery outcomes. Conclusions: Prolonged delivery of either cyclosporine A or everolimus by means of PLA-PEG implants represents a promising strategy of wound healing modulation in glaucoma filtration surgery.

Decorin mediated biomimetic PCL-gelatin nano-framework to impede scarring

Scars occur as a result of fibrosis after tissue damage or surgery and reports suggest that excessive Transforming growth factor-β (TGF-β) activity during the process of wound healing leads to progressive fibrosis. Decorin is an extracellular matrix (ECM) protein which regulates collagen fibrillogenesis. However, targeted delivery and effective protein therapy remains a challenge owing to degradation byproteases. Hence, we aimed to deliver Decorin in a sustainable mode for the reduction of TGF-β levels and subsequent scar formation. Herein, we have fabricated PCL-Gelatin bio-mimetic scaffolds to optimize the bio-activity and provide localized delivery of recombinant Decorin. The degradation and drug release patterns reveals that this biomaterial is biodegradable and offers sustained release of the recombinant Decorin. Decorin loaded nanofiber displayed lower adhesion and proliferation rates in in-vitro conditions. Moreover, Decorin loaded scaffolds demonstrated morphological changes in cells, specifically targeting the myofibroblast. The expression of TGF-β was also scrutinized to understand the effect of Decorin loaded nanofibers. Besides, in the in-vitro fibrotic model, Decorin loaded nanofibers efficiently reduced the expression of ECM related proteins. Therefore, we report the sustained delivery of the recombinant Decorin from nanofiber dressing to potentially obstruct scar formation during the process of wound healing.

[Pharmacological modulation of wound healing in glaucoma surgery]

Despite the well-known effectiveness of pharmacological glaucoma therapy, surgical approach remains one of the main treatment options for some forms and stages of the disease. The long-term success of glaucoma surgery depends on the intensity of local wound healing processes at the surgical site. The most common way to influence healing processes in surgical treatment of glaucoma is the use of antimetabolites. However, given the high risk of serious complications associated with their use, the search for new drugs devoid of these disadvantages continues. The aim of this review is to describe the efficacy and safety of both currently used and upcoming pharmacological ways to influence the wound healing process after glaucoma surgery in order to improve the stability of hypotensive effect.

AGTR1 blocker attenuates activation of Tenon's capsule fibroblasts after glaucoma filtration surgery via the NF-κB signaling pathway

Activation of Tenon's capsule fibroblasts limits the success rate of glaucoma filtration surgery (GFS), the most efficacious therapy for patients with glaucoma. Angiotensin type 1 receptor (AGTR1) is involved in tissues remodeling and fibrogenesis. However, whether AGTR1 is involved in the progress of fibrogenesis after GFS is not fully elucidated. The aim of this study was to investigate the role of an AGTR1 in scar formation after GFS and the potential anti-fibrosis effect of AGTR1 blocker. AGTR1 expression level was increased in subconjunctival tissues in a rat model of GFS and transforming growth factor-beta 2 (TGF-β2)-induced human Tenon's capsule fibroblasts (HTFs). AGTR1 blocker treatment suppressed TGF-β2-induced HTF migration and α-smooth muscle actin (α-SMA) and fibronectin (FN) expression. AGTR1 blocker treatment also attenuated collagen deposition and α-SMA and FN expression in subconjunctival tissues of the rat model after GFS. Moreover, AGTR1 blocker decreased TGF-β2-induced P65 phosphorylation, P65 nuclear translocation, and nuclear factor kappa B (NF-κB) luciferase activity. Additionally, BAY 11-7082 (an NF-κB inhibitor) significantly suppressed HTF fibrosis. In conclusion, our results indicate that AGTR1 is involved in scar formation after GFS. The AGTR1 blocker attenuates subconjunctival fibrosis after GFS by inhibiting the NF-κB signaling pathway. These findings indicate that targeting AGTR1 is a potential approach to attenuate fibrosis after GFS.

Changes in the morphology of the hyperemic blebs in eyes undergone trabeculectomy with mitomycin C after injection of triamcinolone acetonide during one-year follow-up

PURPOSE

To track changes in the morphology of hyperemic blebs in eyes undergone trabeculectomy with mitomycin C 0.02% (MMC) after triamcinolone acetonide (TA) injection.

METHODS

A total of 30 eyes of 30 patients with localized or diffuse hyperemia after trabeculectomy with MMC were enrolled in this prospective interventional case series. Two milligrams of TA were injected at the site of maximal injection. Bleb morphology was graded using Indiana Bleb Appearance Grading Scale (IBAGS), and the Moorfields Bleb Grading System (MBGS) 1 week, 1 month, 3 months, 6 months, and 1 year after injection. Failure was defined as intraocular pressure (IOP) more than predefined target IOP for each eye, need for an additional surgical procedure, IOP less than 6 mmHg, and loss of Light Perception (LP) vision.

RESULTS

A total of 27 patients completed a 1-year follow-up period and were included in the final analysis. The mean time interval from trabeculectomy to injection of TA was 5.98 ± 2.57 weeks. The bleb height and vascularity in the IBAGS system decreased significantly after the intervention (p < 0.05), with an increase in bleb extension (p = 0.006). Using MBGS, the bleb area did not change significantly following TA injection (p = 0.056) but its height and vascularity significantly decreased in both central and peripheral areas and the surrounding conjunctiva (p = 0.032). The development of a mature cataract was the only complication that could be attributed to TA injection.

CONCLUSION

Injection of TA in hyperemic failing blebs improves bleb morphology by decreasing vascularity and height while increasing the extent with an acceptable safety profile.

Trabeculectomy: is releasable suture trabeculectomy a cause of better bleb?

Purpose: To compare the outcome of fixed suture trabeculectomy with releasable suture trabeculectomy in terms of IOP control, bleb morphology, complications and need of antiglaucoma medication post-surgery.

Methods: This study enlisted 200 cases of open angle glaucoma, whose IOP was uncontrolled despite maximal medication. Trabeculectomy was performed using releasable suture in one group of 100 patients and fixed suture in another group of 100 with mitomycin 0.02% in both groups. The study was randomized, the method being the simple randomization. Fornix based trabeculectomy was done in both groups. Two 10-0 nylon releasable sutures were used at two corners of the rectangular flap and one fixed 10-0 vicryl suture was used in the center of the flap. Two mattress sutures (conjunctiva cornea) were also used. Essentially, all the sutures were removed postoperatively over a period of 2-4 weeks depending upon the level of IOP. Mitomycin c 0.02% was used in both groups.

Results: The mean preoperative intraocular pressure was 33 ± 12 mmHg in the single suture group and 39 ± 13 mmHg in the releasable suture group (p). We observed a highly significant reduction of intraocular pressure at all times in both groups compared with the preoperative intraocular pressure (P, 0.0001). There was an obvious difference between the bleb morphology between conventional trabeculectomy and releasable suture trabeculectomy. Blebs in releasable suture trabeculectomy were more diffuse, low lying and presented a more ideal vascularity.

Conclusion: Releasable suture trabeculectomy is a far much better technique than conventional trabeculectomy. Results are very good in terms of IOP control, post-operative complications, and bleb morphology. They may possibly have a role in wound modulation thereby achieving an ideal bleb, though more large sample studies need to be done.

Profile of Secondary Glaucoma at a Tertiary Hospital in East Java

Glaucoma is the leading cause of irreversible blindness. The aim of this study was to review the profile of secondary glaucoma cases visiting a tertiary hospital in East Java. This is retrospective observational study, completed case records of new patients with secondary glaucoma who presented to glaucoma clinic from January 2014 to April 2016 were included. Out of the 363 case records screened, 66 cases were found to eligible for inclusion. The evaluation included a detailed history and examination performed including vision, anterior segment examination, intraocular pressure (IOP), gonioscopy, and fundus evaluation. Diagnosis of secondary glaucoma was made on the basis of presence of a secondary cause for presence of raised IOP. 66 cases were eligible for inclusion in the study, most of the cases was occurred in the range age 21-50 years. The male female ratio was 1.3:1. Frequent causes of secondary glaucoma were lens factor 30.8%, steroid induced 29.5%, uveitic 20.5%, neovascular15.4%, and surgical complication 3.8%. Most patients with secondary glaucoma have poor vision < 0.1 with high IOP at presentation. Assessment and early detection of underlying cause is the key guide to treatment strategy.

Novel Drug Delivery Systems Fighting Glaucoma: Formulation Obstacles and Solutions

Glaucoma is considered to be one of the biggest health problems in the world. It is the main cause of preventable blindness due to its asymptomatic nature in the early stages on the one hand and patients' non-adherence on the other. There are several approaches in glaucoma treatment, whereby this has to be individually designed for each patient. The first-line treatment is medication therapy. However, taking into account numerous disadvantages of conventional ophthalmic dosage forms, intensive work has been carried out on the development of novel drug delivery systems for glaucoma. This review aims to provide an overview of formulation solutions and strategies in the development of in situ gel systems, nanosystems, ocular inserts, contact lenses, collagen corneal shields, ocular implants, microneedles, and iontophoretic devices. The results of studies confirming the effectiveness of the aforementioned drug delivery systems were also briefly presented.

Outcomes of trabeculectomy with polyvinylpyrrolidone collagen versus mitomycin in primary open angle glaucoma. 36-month follow-up

PURPOSE

Describe and compare the effects of intraoperative application of Polyvinylpyrrolidone Collagen (PVP) versus Mitomycin C (MMC) on the pattern of change in mean IOP reduction and mean number of medications over 36-months follow-up in patients with primary open angle glaucoma (POAG) undergoing trabeculectomy.

METHODS

Prospective, randomized, comparative study. Twenty-six eyes of 26 patients with POAG and no previous incisional glaucoma surgery underwent trabeculectomy and were randomized to PVP or MMC and completed a 36-month follow-up. Main outcome measures were IOP and number of glaucoma medications. Multivariate longitudinal analysis was performed by fitting a linear trend model adjusting for baseline response for the IOP outcome and a log-linear regression model with within-subject associations for the number of hypotensive medications outcome. Sensitivity analysis was performed to assess lower and higher order polynomial trends over time in IOP.

RESULTS

The univariate analysis revealed that the mean IOP reduction from baseline to 36 months was 7.62mmHg (3.05; 12.18) in the MMC group and 8.15mmHg (-0.64; 16.95) in the PVP group. Mean percentage IOP reduction from baseline was 37.09% (15.93; 58.17) and 36.08% (5.16; 67.20) in the PVP group. Mean change in number of medications from baseline to 36 months was -0.92 medications (-3.38; +1.54) for the MMC group and -1 medication (-3.12; +1.12) for the PVP group. Both groups had a statistically significant decline in mean IOP over the follow-up period (p<0.001) but there was no discernible difference between the two exposure groups in the rate of change in IOP (p=0.5975). Sensitivity analysis showed that a linear trend model is adequate to describe the IOP reduction over the follow-up period. Both groups had a statistically significant change in the number of hypotensive medications used between baseline and month 36 (p<0.05) but there was no discernible difference between exposure groups (p=0.2917). Both the PVP and MMC groups showed an initial reduction in number of medications until month 12 and a relatively linear increase towards month 36. A longer follow-up may be warranted to reveal differences in the number of medications between the two exposure groups. Postoperative complications were less frequent in the PVP group.

CONCLUSIONS

The use of PVP during trabeculectomy achieves and maintains a statistically significant IOP reduction from baseline to 36 months and decreases the number of glaucoma medications. Secondary outcome measures showed a lower incidence of adverse events in the PVP group.

A Tenon's capsule/bulbar conjunctiva interface biomimetic to model fibrosis and local drug delivery

Glaucoma filtration surgery is one of the most effective methods for lowering intraocular pressure in glaucoma. The surgery efficiently reduces intra-ocular pressure but the most common cause of failure is scarring at the incision site. This occurs in the conjunctiva/Tenon’s capsule layer overlying the scleral coat of the eye. Currently used antimetabolite treatments to prevent post-surgical scarring are non-selective and are associated with potentially blinding side effects. Developing new treatments to target scarring requires both a better understanding of wound healing and scarring in the conjunctiva, and new means of delivering anti-scarring drugs locally and sustainably. By combining plastic compression of collagen gels with a soft collagen-based layer, we have developed a physiologically relevant model of the sub-epithelial bulbar conjunctiva/Tenon’s capsule interface, which allows a more holistic approach to the understanding of subconjunctival tissue behaviour and local drug delivery. The biomimetic tissue hosts both primary human conjunctival fibroblasts and an immune component in the form of macrophages, morphologically and structurally mimicking the mechanical proprieties and contraction kinetics of ex vivo porcine conjunctiva. We show that our model is suitable for the screening of drugs targeting scarring and/or inflammation, and amenable to the study of local drug delivery devices that can be inserted in between the two layers of the biomimetic. We propose that this multicellular-bilayer engineered tissue will be useful to study complex biological aspects of scarring and fibrosis, including the role of inflammation, with potentially significant implications for the management of scarring following glaucoma filtration surgery and other anterior ocular segment scarring conditions. Crucially, it uniquely allows the evaluation of new means of local drug delivery within a physiologically relevant tissue mimetic, mimicking intraoperative drug delivery in vivo.

Needling after trabeculectomy - does augmentation by anti-metabolites provide better outcomes and is Mitomycin C better than 5-Fluoruracil? A systematic review with network meta-analyses

PURPOSE

Favourable outcome after glaucoma surgery depends on proper control of the inflammatory response. Failing filtration bleb and consequently increased intraocular pressure is an important cause of continuous visual field deterioration after uncomplicated glaucoma surgery. The present systematic review and meta-analysis aimed to compare the effects of employing either Mitomycin C (MMC), 5-Fluoruracil (5-FU) or no anti-metabolite in needling revision of trabeculectomies.

METHODS

We performed a systematic literature search in PubMed, Cochrane and EMBASE to identify randomized and non-randomized trials published between year 2000 and March 2019 comparing the efficacy of needling filtering blebs when using no anti-fibrotic agent, MMC or 5-FU in patients with glaucoma. Efficacy was defined as intraocular pressure at 12 months or latest follow-up, rate of complications, rates of success and the number of re-needling cases. Comparisons were made using network meta-analyses.

RESULTS

We identified one randomized trial and five retrospective trials. Twelve months after needling revision of trabeculectomy, no significant difference was observed when comparing the effect of the use of MMC with 5-FU or without any use of anti-metabolite on intraocular pressure, complication rates, qualified success, complete success or number of re-needling cases.

CONCLUSION

We found no significant difference in the efficacy of using either MMC, 5-FU or no anti-metabolite in needling revision of trabeculectomies. The number of studies meeting our inclusion criteria was limited. Considering the design of studies, only one was randomized leading to an overall low quality of evidence on the subject matter. Further research is warranted.

The Expression and Role of Hypoxia-induced Factor-1α in Human Tenon's Capsule Fibroblasts under Hypoxia

PURPOSE

To determine the expression of hypoxia-induced factor-1α (HIF-1α) and its downstream factors in human Tenon's capsule fibroblasts (HTFs) and changes in HTFs biological functions, we explored the role of HIF-1α in HTFs under hypoxia to provide a basis for studying the regulation of HIF-1α in wound healing after glaucoma surgery.

MATERIALS AND METHODS

we established HTFs hypoxia model in vitro, meanwhile the HIF-1α agonist VH298 or inhibitor KC7F2 was added to HTFs, and the normoxia group was used as a control. Western blot, immunofluorescence and ELISA were used to detect the expression of HIF-1α, vascular endothelial growth factor (VEGF), transforming growth factor-β (TGF-β), Smads and collagen I. The proliferation of HTFs was quantified by cell counting kit-8, and cell migration was tested by healing scratch test.

RESULTS

HIF-1α protein expression increased under hypoxia, peaked from 4-24 h, and then decreased. The secretion of VEGF and TGF-β increased with prolonged hypoxia time. VH298 and KC7F2 upregulated and downregulated the levels of VEGF and TGF-β, respectively, suggesting that HIF-1α upregulates and downregulates the levels of VEGF and TGF-β in HTFs under hypoxia, respectively. HIF-1α upregulated the proliferation, migration and collagen synthesis of HTFs under hypoxia.

CONCLUSIONS

Regulating HIF-1α and its downstream factors effectively regulated HTFs proliferation, migration and collagen synthesis. HIF-1α is a promising regulator in the study of wound healing after glaucoma surgery.

[Medicated prevention of scarring after glaucoma surgery]

Modulation of wound healing is one of the main challenges in glaucoma surgery. Modern antiproliferative agents used to reduce postoperative scarring are either insufficiently effective or inadequate in terms of safety. In the search for novel agents devoid of such drawbacks, specialists directed their attention to selective inhibitors of proinflammatory cytokines and growth factors. The article reviews pathophysiologic basis of wound healing, characteristics of inflammatory mediators affecting fibroblast proliferation and scarring, and provides description of the currently used and new, potentially promising antiproliferative agents.

Scleral concave pool trabeculectomy combined phacoemulsification in primary open-angle glaucoma with cataract

Background

To investigate the safety and efficacy of scleral concave pool trabeculectomy (SCPT) combined phacoemulsification for eyes with coexisting cataract and primary open-angle glaucoma (POAG).

Methods

This was a retrospective, controlled, interventional pilot case series. Thirty patients (30 eyes) were diagnosed with coexisting cataract and POAG between May 2015 and April 2018. Fourteen eyes underwent SCPT combined phacoemulsification were set as the study group, and 16 eyes received conventional phacotrabeculectomy were set as the control group. All patients were followed up for at least 6 months. The preoperative to postoperative changes in IOP, glaucoma medication requirements, BCVA, blebs functions, and adverse events were recorded.

Results

The groups were matched for baseline age, BCVA, IOP and types of IOP-lowering medications (all P > 0.05). At 6-month visit, there were no significant difference between control and study group in the improvement of BCVA (0.22 ± 0.24 versus 0.18 ± 0.26, P = 0.718), reduction of IOP (− 11.21 ± 8.61 mmHg versus − 9.19 ± 9.18 mmHg, P = 0.540) and the number of eyes that needed IOP-lowering medications (2 versus 3, P = 0.743). At the last visit, the rate of forming functioning blebs was significantly different between the study and control groups, (92.9% versus 68.7% respectively, P = 0.007). In the study group, 5 eyes developed hypotony, and 1 eye showed limited choroidal detachment, whereas in the control group 1 eye developed malignant glaucoma. All adverse events were successfully managed.

Conclusion

The SCPT combined phacoemulsification seems to be a safe and effective alternative to conventional phacotrabeculectomy for patients with POAG and visually significant cataract in the short-term.

Visual field progression 8 years after trabeculectomy in Asian eyes: results from The Singapore 5-Fluorouracil Study

BACKGROUND/AIMS

This work aimed to study the effect of long-term intraocular pressure (IOP) fluctuation on visual field (VF) progression 8 years post-trabeculectomy in Asian eyes.

METHODS

This was a retrospective analysis of 8-year post-trabeculectomy data from The Singapore 5-Fluorouracil (5-FU) Study. VFs were analysed using Progressor software (Medisoft, Leeds, UK). Outcome measures included mean slope for VF per year, number of progressing points and mean slope for progressing points per year. Multivariate regression analyses were performed adjusting for age, gender, ethnicity, glaucoma type, intraoperative 5-FU, diabetes mellitus, hypertension, best pre-trabeculectomy VF mean deviation, post-trabeculectomy mean IOP, IOP reduction and IOP fluctuation (SD of IOPs at 6-monthly timepoints).

RESULTS

127 (52.3%) subjects completed 8-year follow-up with ≥5 reliable VFs and ≥8 6-monthly IOP measurements. Mean age was 61.8±9.6 years. Post-operatively, mean IOP was 14.2±2.8 mm Hg and mean IOP fluctuation was 2.53±1.20 mm Hg. Higher IOP fluctuation was associated with greater mean slope for field (B=-0.071; p=0.013), number of progressing points (B=0.963; p=0.014) and VF progression as defined by ≥1 progressing point (OR=1.585; p=0.029). There was also a trend towards eyes with higher IOP fluctuation having ≥3 adjacent progressing points in the same hemifield (OR=1.489; p=0.055). Greater mean IOP reduction post-trabeculectomy was associated only with a lower mean slope for progressing points per year (B=-0.026; p=0.028). There was no significant effect of intra-operative 5-FU compared with placebo for all outcome measures.

CONCLUSION

In post-trabeculectomy Asian eyes with well-controlled IOP, higher long-term IOP fluctuation may be associated with greater VF progression.

Effect of multiple subconjunctival conbercept injections as an adjuvant to the surgical treatment of pterygium: a prospective randomised comparative 6-month follow-up study

OBJECTIVE

To evaluate the safety and efficacy of multiple subconjunctival injections of conbercept for pterygium patients after surgery.

METHODS

As a prospective randomised interventional trial, 96 eyes from 96 patients with a tendency to recur were collected and divided randomly into conbercept and 5-fluorouracil groups on the 5th day after pterygium. All patients received three subconjunctival injections of conbercept (0.2 ml) or 5-fluorouracil (0.2 ml) on the 5th day (baseline), and 2 and 4 weeks post-operatively. The pterygium morphology, colour intensity, recurrence, and complications were recorded and analysed pre-1st injection and 1 day, 1 week, 1 month, 3 months, and 6 months post-3rd injection. Moreover, no patient was drop-out.

RESULTS

There were striking differences between the two groups on post-3rd injections 1 day, 1 week, 1 month, 3 months, and 6 months (p = 0.001, 0.002, 0.000, 0.000, and 0.002, respectively) with respect to colour intensity: the eyes in conbercept group were lighter than the 5-Fu group. On post-3rd injection 6 months, prominent disparities existed between the two groups with respect to pterygium morphology (p = 0.006) and recurrence (p = 0.002), occurred in the conbercept group prior to the 5-Fu group. Moreover, corneal abrasions were not noted in the conbercept group, which was significantly less than the 5-Fu group (17/48; p = 0.000). There was no conspicuous discrepancy between the two groups with respect to subconjunctival haemorrhage (p = 0.789) and persistent epithelial defects (p = 0.078).

CONCLUSION

Multiple subconjunctival conbercept injections as an adjunct therapy for pterygium surgery was shown to be safe, effective, and well-tolerated.

Effect of trabeculectomy on corneal endothelial cell loss

AIM

To investigate changes in corneal endothelial cell density (CECD) after trabeculectomy.

METHODS

This prospective, observational study followed 117 eyes of 117 patients for 2 years after trabeculectomy. The central cornea was examined by corneal specular microscopy prior to and at every 6 months after the surgery. Survival analysis of patients who exhibited a 10% or less reduction of the postoperative CECD compared with preoperative levels was assessed using the Kaplan-Meier survival curve. A Cox proportional hazards model was used to evaluate prognostic factors for decreasing CECD.

RESULTS

At baseline, the mean CECD was 2420±357 cells/mm², while at 6, 12, 18 and 24 months after surgery, the mean CECD was 2324±373 cells/mm² (p<0.001), 2276±400 cells/mm² (p<0.001), 2290±398 cells/mm² (p<0.001) and 2267±446 cells/mm² (p<0.001), respectively. At 6, 12, 18 and 24 months after surgery, the results of the Kaplan-Meier survival analysis of the 10% loss of CECD from baseline were 91%, 85%, 83% and 77%, respectively. Uveitic glaucoma was a significant prognostic factor for decreasing CECD (p=0.041).

CONCLUSIONS

CECD significantly and continuously decreased after trabeculectomy.

Differential effects of dexamethasone and indomethacin on Tenon's capsule fibroblasts: Implications for glaucoma surgery

Dysregulated wound healing and subsequent fibrosis represents the most common cause of failure in glaucoma filtration surgery. Primary means to prevent this outcome are the anti-metabolite surgical adjuvants, however, topical corticosteroids are commonly used postoperatively to permit further control of wound healing and development of the filtration bleb. Unfortunately, they carry important side effects such as raised intraocular pressure, cataract and increased infection risk. Non-steroidal anti-inflammatory drugs (NSAIDs) show promising results in clinical trials as an alternative wound modulatory drug. NSAIDs exhibit non-inferiority to steroids in terms of post-operative intraocular pressure control and secondary IOP lowering interventions, however there is little known about the differing effects these drugs exert on human Tenon's capsule fibroblast (HTCF) mediated wound healing. The purpose of this study was to assess the individual effects of dexamethasone and indomethacin on the extracellular matrix modifying actions of HTCFs in vitro. To this end, HTCFs were cultured in 3D collagen matrices as well as in 2D monolayers and exposed to clinically relevant concentrations of dexamethasone or indomethacin for up to seven days. HTCF-mediated wound healing functions were assayed through collagen matrix contraction, extracellular matrix morphology, estimation of HCTF proliferation and differentiation into myofibroblasts within the collagen matrices, as well as western blot. Both drugs significantly reduced HTCF-mediated collagen contraction relative to control however there was a significant trend towards greater inhibition with indomethacin exposure compared to dexamethasone. Indomethacin exposure significantly reduced HTCF-mediated collagen remodelling activity compared vehicle control, whereas dexamethasone was unable to reduce remodelling activity at any of the studied exposures. Both drugs reduced myofibroblast differentiation, however indomethacin alone demonstrated an inhibitory effect on final cell number relative to control whereas dexamethasone had no significant effect at any studied exposure. These findings demonstrate that both steroidal and NSAID treatment can mitigate HTCF-mediated collagen contraction and αSMA expression. However, NSAIDs may function to better impede HTCF proliferation and remodelling activity. Taken in the context of previous glaucoma surgical trials, NSAIDs appear to be a viable alternative to steroids for post-operative wound modulation.

Steroids and nonsteroidal anti-inflammatory drugs in the postoperative regime after trabeculectomy - which provides the better outcome? A systematic review and meta-analysis

Surgical outcome after trabeculectomy depends on maintaining a functional bleb which requires a delicate balance between incomplete wound healing to prevent fibrosis and enough wound healing to prevent hyperfiltration. Thus, controlling the inflammatory response is essential. We conducted a systematic review and meta-analysis to compare the effectiveness of different formulations of steroids (topical, systemic and depot) and nonsteroidal anti-inflammatory drugs (NSAIDs) in achieving long-term pressure control with fewer antiglaucomatous medications, preserving visual acuity and visual fields while considering surgical and postoperative complications. We used the PubMed, EMBASE and Cochrane Libraries to identify randomized controlled trials (RCTs) comparing the effect of different formulations of steroids (topical, systemic or depot) to NSAIDs. Data on prespecified outcomes from eligible references were entered into a meta-analysis using the Review Manager 5.3 program. We identified seven RCTs with a total of 342 included patients. Topical steroids were superior to placebo in controlling intraocular pressure (IOP) and reducing the risk of complications. Supplementing topical steroids with a perioperative steroid depot (subtenon or intracamerally) or systemic steroids in the early postoperative period did not provide better outcome or a change in the risk of complications. Addition of topical NSAIDs to topical steroids in patients undergoing trabeculectomy did not change the outcome or risk profile. For patients undergoing phacotrabeculectomy and topical NSAID, there was a nonsignificant trend towards better intermediate IOP control and a reduced need for antiglaucomatous medications compared to topical steroids but there was no difference in effect for patients undergoing trabeculectomy. In conclusion, there is a low level of evidence to support the clinician in deciding which postoperative regime provides a more favourable outcome because of inconsistency in the reported outcomes between studies and a low number of patients for each comparable intervention and outcome. It does seem that topical steroids are better than no anti-inflammatory treatment after glaucoma surgery, but further research is recommended.

Effect of subconjunctival injection with conbercept as an adjuvant to filtration surgery for open angle glaucoma: a prospective randomized interventional 6-month follow-up study

AIM

To compare the safety and efficacy of subconjunctival injection with conbercept and 5-fluorouracil (5-FU) for open angle glaucoma (OAG) patients after filtration surgery.

METHODS

As a prospective randomized interventional trial, 36 eyes from 36 patients after OAG surgery were collected and divided randomly into conbercept and 5-FU groups. All patients were subconjunctivally injected with either conbercept (0.2 mL) or 5-FU (0.2 mL) on the 5^th day post-operatively. The intraocular pressure (IOP), number of medications used, type of conjunctival bleb, and complications were recorded and analyzed pre-operatively and 1d, 1wk, 1, 3 and 6mo post-injection.

RESULTS

There were significant differences in IOP between the conbercept and 5-FU groups 1mo (conbercept group: 12.17±1.04 mm Hg; 5-FU group: 13.50±2.33 mm Hg, t=2.214, P=0.037), 3mo (conbercept group: 13.00±1.88 mm Hg; 5-FU group: 14.50±2.28 mm Hg, t=2.153, P=0.039), and 6mo post-injection (conbercept group: 13.28±2.95 mm Hg; 5-FU group: 15.22±2.49 mm Hg, t=2.140, P=0.040); however, in the number of medications, a prominent difference was not shown between groups on post-injection 6mo (t=1.312, P=0.200). Moreover, there was mild vascularity observed in the conbecept group than the 5-FU group 1d (3a, 3b, 3c: t=8.497, 6.693, 4.515, P=0.000), 1wk (3a, 3b, 3c: t=3.431, 6.408, 3.984, P=0.002, 0.000, 0.000), and 1mo post-injection (3a, 3b, 3c: t=2.466, 2.466, 2.503, P=0.019, 0.019, 0.017). Simultaneously, differences from other indicators between the two groups were not demonstrated. Also, there was a lower probability of corneal epithelial stripping in the conbercept group than the 5-FU group (χ ²=4.500, P=0.034).

CONCLUSION

Subconjunctival injection of conbercept has a safe, effective, and tolerable profile for open angle glaucoma patients with distinct conjunctival congestion after filtration surgery.

Prospective pilot study comparing deep sclerectomy outcomes with a long-term and intense corticosteroid treatment versus a standard one

Objective

To compare prospectively intraocular pressure (IOP) results after deep sclerectomy (DS) using a topical short-term corticosteroid treatment (STCT, 1  month) versus a topical long-term and intense corticosteroid treatment (LTCT, 6 months) in a two2  year-follow-up.

Methods

Patients with medically uncontrolled open angle glaucoma were prospectively recruited and underwent a DS.

Results

We operated 45 eyes of 45 patients, 22 in STCT group and 23 in LTCT group. Median preoperative IOP was 27 (22-36.75)  mm Hg for STCT and for 25 (22-28) mm Hg for LTCT group without significant difference (p=0.195). Median postoperative IOP was 4 (3-6.25) mm Hg in STCT group versus 2 (0-5)  mm Hg in LTCT at day 1 (p=0.003); 8.5 (5.75-11.25)  mm Hg (STCT) vs 6 (4-9) mm Hg (LTCT) at week 1 (p=0.079); 17.5 (14.75-22.25)  mm Hg (STCT) vs 13 (10-14) mm Hg (LTCT) at month 1 (p=0.001); 16 (12-20) mm Hg (STCT) vs 12 (10-15) mm Hg (LTCT) at month 3 (p=0.008); 17 (14-20) mm Hg (STCT) vs 12 (10-14) mm Hg (LTCT) at month 6 (p=0.000); 16 (14-20) mm Hg (STCT) vs 14 (10-16) mm Hg (LTCT) at year 1 (p=0.002) and 17.5 (15-19)  mm Hg (STCT) vs 14 (12-16) mm Hg (LTCT) at year 2 (p=0.001). The complete success rate was 54.5 % in STCT and 87 % in LTCT (p=0.018).

Conclusions

A long-term and intensive postoperative treatment enhances success rate in DS compared with a standard protocol.

Development of a biodegradable antifibrotic local drug delivery system for glaucoma microstents

To prevent implant failure due to fibrosis is a major objective in glaucoma research. The present study investigated the antifibrotic effects of paclitaxel (PTX), caffeic acid phenethyl ester (CAPE), and pirfenidone (PFD) coated microstent test specimens in a rat model. Test specimens based on a biodegradable blend of poly(4-hydroxybutyrate) biopolymer and atactic poly(3-hydroxybutyrate) (at.P(3HB)) were manufactured, equipped with local drug delivery (LDD) coatings, and implanted in the subcutaneous white fat depot. Postoperatively, test specimens were explanted and analyzed for residual drug content. Fat depots including the test specimens were histologically analyzed. In vitro drug release studies revealed an initial burst for LDD devices. In vivo, slow drug release of PTX was found, whereas it already completed 1 week postoperatively for CAPE and PFD LDD devices. Histological examinations revealed a massive cell infiltration in the periphery of the test specimens. Compact fibrotic capsules around the LDD devices were detectable at 4–36 weeks and least pronounced around PFD-coated specimens. Capsules stained positive for extracellular matrix (ECM) components. The presented model offers possibilities to investigate release kinetics and the antifibrotic potential of drugs in vivo as well as the identification of more effective agents for a novel generation of drug-eluting glaucoma microstents.

Efficacy of autologous conjunctival flap on repairing the late-onset filtering bleb leakage

AIM

To evaluate the effectiveness of autologous conjunctival flap surgery for repairing the late-onset filtering bleb leakage after trabeculectomy.

METHODS

This study retrospectively reviewed 106 eyes from 106 patients with late-onset filtering bleb leakage after trabeculectomy who received autologous conjunctival flap surgery at the Zhongshan Ophthalmic Centre from 2005 to 2015. The basic information was recorded, and the interval time between trabeculectomy and autologous conjunctival flap surgery as well as related risk factors, intraocular pressure (IOP), anterior chamber depth (ACD) and best corrected visual acuity (BCVA) were analysed. Moreover, 41 patients who completed the 1-year follow up were analysed to determine the IOP and BCVA changes and long-term success rates.

RESULTS

The 50 male and 56 female subjects (average age 39.13±17.96y) included 47 (44.34%) and 33 (31.13%) cases of primary open angle and primary angle-closure glaucoma. The mean interval between trabeculectomy and repair surgery was 60.60±56.92 (3-264)mo. The mean mitomycin (MMC) concentration during trabeculectomy was 0.27±0.04 (0.12-0.4) mg/mL in the fornix-based conjunctival flap group (68 patients) and 0.28±0.04 (0.20-0.33) mg/mL in the limbal-based conjunctival flap group (11 patients). After bleb leakage, the patients' vision remained stable while the IOP decreased from 10.25±4.76 (3-20.86) to 9.44±4.33 (2-21) mm Hg (P<0.01). In the 41 analysed patients, the IOP was controlled at 15.68±5.11 (7-40) mm Hg in the 1^st year after autologous conjunctival flap surgery and recurrence was not observed, for a long-term success rate of 100%.

CONCLUSION

Autologous conjunctival flap repairing surgery is an effective technique for sealing filtering bleb leakages and controlling IOP postoperatively.

First-in-human phase I study of ISTH0036, an antisense oligonucleotide selectively targeting transforming growth factor beta 2 (TGF-β2), in subjects with open-angle glaucoma undergoing glaucoma filtration surgery

Purpose

To evaluate the safety and tolerability of intravitreal ISTH0036, an antisense oligonucleotide selectively targeting transforming growth factor beta 2 (TGF-β2), in patients with primary open angle glaucoma (POAG) undergoing trabeculectomy (TE; glaucoma filtration surgery).

Methods

In this prospective phase I trial glaucoma patients scheduled for TE with mitomycin C (MMC) received a single intravitreal injection of ISTH0036 at the end of surgery in escalating total doses of 6.75 μg, 22.5 μg, 67.5 μg or 225 μg, resulting in calculated intraocular ISTH0036 concentrations in the vitreous humor of approximately 0.3 μM, 1 μM, 3 μM or 10 μM after injection, respectively. Outcomes assessed included: type and frequency of adverse events (AEs), intraocular pressure (IOP), numbers of interventions post trabeculectomy, bleb survival, visual acuity, visual field, electroretinogram (ERG), slit lamp biomicroscopy and optic disc assessment.

Results

In total, 12 patients were treated in the 4 dose groups. Main ocular AEs observed were corneal erosion, corneal epithelium defect, or too high or too low IOP, among others. No AE was reported to be related to ISTH0036. All other safety-related analyses did not reveal any toxicities of concern, either. The mean medicated preoperative IOP at decision time-point for surgery was 27.3 mmHg +/- 12.6 mmHg (SD). Mean IOP (±SD) for dose levels 1, 2, 3, and 4 were at Day 43 9.8 mmHg ± 1.0 mmHg, 11.3 mmHg ± 6.7 mmHg, 5.5 mmHg ± 3.0 mmHg and 7.5 mmHg ± 2.3 mmHg SD; and at Day 85 9.7 mmHg ± 3.3 mmHg, 14.2 mmHg ± 6.5 mmHg, 5.8 mmHg ± 1.8 mmHg and 7.8 mmHg ± 0.6 mmHg, respectively. In contrast to IOP values for dose levels 1 and 2, IOP values for dose levels 3 and 4 persistently remained below 10 mmHg throughout the observation period.

Conclusion

This first-in-human trial demonstrates that intravitreal injection of ISTH0036 at the end of TE is safe. Regarding IOP control, single-dose ISTH0036 administration of 67.5 μg or 225 μg at the time of TE resulted in IOP values persistently < 10 mmHg over the three month postoperative observation period.

Management of neovascular glaucoma with intravitreal ranibizumab, panretinal photocoagulation, and subsequent 5-fluorouracil augmented trabeculectomy: A case report

RATIONALE

Neovascular glaucoma (NVG) is one of the most refractory types of glaucoma caused by high ischemic retinal disorders, resulting in severe visual loss. Intravitreal injections of ranibizumab have been reported to have anatomical and functional success in treating NVG.

PATIENT CONCERNS-DIAGNOSES-INTERVENTIONS

We report a case with neovascular glaucoma due to central retinal vein occlusion who received combination therapy with intravitreal ranibizumab (IVR) injection, panretinal photocoagulation (PRP) and subsequent 5-fluorouracil (5-FU) augmented trabeculectomy.

OUTCOMES

One week after IVR injection, the intraocular pressure (IOP) had partially decreased to 33 mmHg, and there was a complete regression of neovascularization of the iris (NVI) and the angle (NVA). PRP was feasible after IVR due to improvement of corneal edema which made an adequate view of the posterior pole of fundus. The surgery of trabeculectomy with 5-FU was performed 2 weeks after IVR to control the IOP. The intraoperative and postoperative courses were uneventful without any adverse complication. Post trabeculectomy, his vision remained stable and the IOP was in the range of 4-15 mmHg without topical antiglaucoma medications. A functioning bleb was maintained and there was no recurrence of NVI and NVA during the complete follow-up period of 6 months.

LESSONS

Combined treatment of IVR, PRP, and subsequent 5-FU augmented trabeculectomy is demonstrated to be a possible new paradigm for the management of advanced NVG with angle closure and intractable elevation of IOP.

Silibinin Inhibits Platelet-Derived Growth Factor-Driven Cell Proliferation via Downregulation of N-Glycosylation in Human Tenon's Fibroblasts in a Proteasome-Dependent Manner

The objective of this study was to evaluate the effects of silibinin on cell proliferation in platelet-derived growth factor (PDGF)-treated human Tenon's fibroblasts (HTFs). The effect of silibinin on cell proliferation in PDGF-treated HTFs was determined by examining the expression of proliferating cell nuclear antigen (PCNA) and performing WST-1 assays. Cell cycle progression was evaluated using flow cytometry. The related cyclins and cyclin-dependent kinases (CDKs) were also analyzed using western blot. A modified rat trabeculectomy model was established to evaluate the effect of silibinin on cell proliferation in vivo. Western blot analysis was carried out to determine the effect of silibinin on the expression of PDGF receptor and on the downstream signaling pathways regulated by PDGF receptor. PDGF elevated the expression of PCNA in HTFs, and this elevation was inhibited by silibinin. The inhibitory effect of silibinin on cell proliferation was also confirmed via WST-1 assay. PDGF-stimulated cell cycle in HTFs was delayed by silibinin, and the related cyclin D1 and CDK4 were also suppressed by silibinin. In the rat model of trabeculectomy, silibinin reduced the expression of PCNA at the site of blebs in vivo. The effects of silibinin on PDGF-stimulated HTFs were mediated via the downregulation of PDGF receptor-regulated signaling pathways, such as ERKs and STATs, which may be partially caused by the downregulation of N-glycosylation of PDGF receptor beta (PDGFRβ). The effect of silibinin on modulation of N-glycosylation of PDGFRβ was mediated in a proteasome-dependent manner. Silibinin inhibited cell proliferation and delayed cell cycle progression in PDGF-treated HTFs in vitro. PDGF also modulated the process of N-glycosylation of the PDGFRβ in a proteasome-dependent manner. Our findings suggest that silibinin has potential therapeutic applications in glaucoma filtering surgery.