Effect of trabeculectomy on visual field progression in Japanese progressive normal-tension glaucoma with intraocular pressure < 15 mmHg

Sector-specific Association of Intraocular Pressure Dynamics in Dark-room Prone Testing and Visual Field Defect Progression in Glaucoma

PURPOSE

To investigate sectoral differences in the relationship between intraocular pressure (IOP) dynamics during dark-room prone testing (DRPT) and visual field (VF) defect progression in primary open-angle glaucoma (POAG) patients.

DESIGN

Retrospective, longitudinal study.

PARTICIPANTS

This retrospective study included 116 eyes of 84 POAG patients who underwent DRPT and had at least 5 reliable VF tests conducted over a more than 2-year follow-up period. We excluded eyes with mean deviation worse than -20 dB or a history of intraocular surgery or laser treatment.

METHODS

Average total deviation (TD) was calculated in the superior, central, and inferior sectors of the Humphrey 24-2 or 30-2 program. During DRPT, IOP was measured in the sitting position, and after 60 minutes in the prone position in a dark room, IOP was measured again. The relationship between IOP change during DRPT, IOP after DRPT, and TD slope in each quadrant was analyzed with a linear mixed-effects model, adjusting for other potential confounding factors.

MAIN OUTCOME MEASURES

Total deviation slope in each quadrant, IOP change during DRPT, and IOP after DRPT.

RESULTS

Intraocular pressure after DRPT and IOP change during DRPT were 18.16 ± 3.42 mmHg and 4.92 ± 3.12 mmHg, respectively. Superior TD slope was significantly associated with both IOP after DRPT (β = -0.28, P = 0.003) and IOP change during DRPT (β = -0.21, P = 0.029), while central (β = -0.05, P = 0.595; β = -0.05; P = 0.622) and inferior (β = 0.05, P = 0.611; β = 0.01, P = 0.938) TD slopes were not.

CONCLUSION

Dark-room prone testing might be a useful test to predict the risk of superior VF defect progression in eyes with POAG.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Comparing Outcomes of 45 Xen Implantation Ab Interno With Closed Conjunctiva to Ab Externo With Open Conjunctiva Approaches

PRCIS

Ab externo with open conjunctiva placement may lead to improved gelatin stent (XEN Gel Stent; Allergan) success rate compared with ab interno with closed conjunctiva because it conferred more favorable intraocular pressure (IOP) and medication burden reduction based on our complete and qualified success criteria.

PURPOSE

To compare outcomes of a gelatin stent (XEN 45 Gel Stent; Allergan) placed either ab interno with closed conjunctiva (AIC) or ab externo with open conjunctiva (AEO) with or without cataract surgery in patients with glaucoma.

DESIGN

Retrospective, nonrandomized comparative study of 85 eyes from 85 glaucoma patients who received XEN 45 Gel Stent placed either AIC (N=32) or AEO (N=53) with or without cataract surgery between July 2018 and January 2022 at Massachusetts Eye and Ear. Patients were included if they were 18 years of age or above and had at least 30 days of follow-up without any disqualifying event.

RESULTS

Baseline demographics were similar between both groups, except for the glaucoma type. Both AIC and AEO procedures resulted in significant patterns of IOP and medication reduction from baseline up to 1 year. At postoperative year (POY)1, mean IOP was reduced to 11.34±4 mmHg on 1.29±1.34 medications after AEO and 13.70±3.32 mmHg on 2±1.81 medications after AIC. The average IOP reduction was significantly greater in the AEO group at all postoperative time points beyond postoperative week 2. There were significant differences in the survival curves of AEO and AIC groups under both the complete success criteria and the qualified success criteria. Under the complete success criteria, the cumulative probability of survival at POY1 was 28.5% in the AEO group and 3.8% in the AIC group. Under the qualified success criteria, the cumulative probability of survival at POY1 was 60.3% in the AEO group and 21.9% in the AIC group.

CONCLUSIONS

In our study, we demonstrate that both placements reduce IOP and medication from baseline, with AEO placement having more favorable success rates compared with AIC placement.

Long-Term Surgical Outcomes of Glaucoma Drainage Implants in Eyes with Preoperative Intraocular Pressure Less than 19 mmHg

Background

This retrospective review reports on patients who underwent glaucoma drainage implant (GDI) surgery and had baseline intraocular pressure (IOP) of ≤18 mmHg with at least one year of follow-up.

Methods

Clinical data of 67 eyes of 67 patients were collected from patients' charts, and the outcomes of GDI were evaluated until 7 years. GDI failure was defined as IOP reduction of less than 20% from the baseline at two consecutive visits three months after surgery, decline to no light perception, or if additional glaucoma surgery was performed.

Results

The average age was 65.9 ± 13.2 years. Most cases were male (52.2%), White (53.7%), and had primary open-angle glaucoma (62.7%). Forty-four eyes had prior glaucoma surgery (68.6%) and 46 (68.6%) had severe glaucoma. Though postoperative (postop) IOP changes were insignificant, the average postop number of medications dropped from 2.4 ± 1.4 to 1.9 ± 1.2 medications two years after surgery (p = 0.0451). Postop complications (23.9%) included GDI exposure (7.5%), inflammation (4.5%), shallow anterior chamber (4.5%), and strabismus (1.5%). Hypotony was observed in 4 eyes (5.9%), none of which developed hypotony maculopathy. The cumulative one-year failure rate was 56.7%, most of which were due to failure to lower IOP.

Conclusion

In patients with baseline IOP ≤18 mmHg who had GDI surgery, though the change in IOP was not statistically significant, the number of medications dropped and visual field progression slowed in a subset of patients with adequate perimetric data. Due to a relatively high rate of complications and limited effectiveness in lowering IOP, GDI should be cautiously used in these eyes.

Influence of Trabeculectomy with Mitomycin C on Longitudinal Changes in the Visual Field in Glaucoma Patients with High Myopia

Purpose

To evaluate the effect of trabeculectomy (Trab MMC) on visual field (VF) progression in eyes with glaucoma and high myopia.

Patients and Methods

Patients diagnosed with primary open-angle glaucoma or exfoliation glaucoma who underwent Trab MMC as the first glaucoma surgery along with ≥3 VF tests preoperatively and postoperatively were enrolled. High myopia was defined as an axial length ≥26.5 mm. Postoperative reductions in intraocular pressure (IOP) were assessed by survival analysis using IOP measurements obtained preoperatively. The longitudinal trends of the outcome measures were evaluated using linear mixed models.

Results

Thirty-five eyes of 32 patients were included in this study, including 22 eyes of 20 patients in non-highly myopic group and 13 eyes of 12 patients in highly myopic group. IOP decreased after Trab MMC, and the survival rate did not differ significantly in relation to axial length. Linear mixed-model analyses suggested that the inhibitory effects of Trab MMC on the rate of mean deviation (MD) changes were significant in the non-highly myopic group (-0.53 ± 0.15 dB/year preoperatively to -0.16 ± 0.13 dB/year postoperatively; P = 0.004), but not in the highly myopic group (-0.66 ± 0.19 dB/year preoperatively to -0.48 ± 0.18 dB/year postoperatively; P = 0.32).

Conclusion

Trab MMC reduced IOP in both highly myopic and non-highly myopic eyes, and IOP reduction was very similar in both groups. The VF deterioration rate decreased in both groups, but the change was weaker and nonsignificant in the highly myopic group.

12-month outcomes of ab interno excisional goniotomy combined with cataract surgery in primary open-angle glaucoma and normal tension glaucoma

PURPOSE

To evaluate the efficacy and safety of excisional goniotomy performed with the Kahook Dual Blade (KDB) combined with cataract surgery in patients with pimary open angle glaucoma (POAG) and Normal Tension Glaucoma (NTG) under topical therapy. Further sub-analysis was performed to compare between 90 and 120 degrees goniotomy.

METHODS

This was a prospective case series of 69 eyes from 69 adults (age 78 ± 5.9 years; male = 27, female = 42). Indications for surgery included insufficient IOP control with topical medication, glaucomatous damage progression under topical therapy and reduction of medication burden. Complete success was defined as IOP lowering below 21 mmHg without the need for topical medication. For NTG patients, complete success was defined as IOP lowering below 17 mmHg without the need for topical medication.

RESULTS

IOP was significantly lowered from 19.7 ± 4.7 to 15.1 ± 2.7 at 2 months, 15.8 ± 2.3 at 6 months and 16.1 ± 3.2 at 12 months (p < 0.05) for POAG and 15.1 ± 2.5 to 14.1 ± 2.4 at 2 months, 14.1 ± 3.1 at 6 months and 13.6 ± 1.8 at 12 months (p > 0.08) for NTG, respectively. Complete success was achieved in 64% of the patients. IOP lowering under 17 mmHg without the need for topical medication was achieved in 60% of the patients at 12 months. In NTG patients (14 eyes) IOP lowering under 17 mmHg without the need for topical medication was achieved in 71%. No significant difference was recorded in terms of IOP lowering at 12 months in-between 90° and 120° of treated trabecular meshwork (p > 0.7). No severe adverse reactions were recorded in this study.

CONCLUSION

One-year results show that KDB combined with cataract surgery is an effective treatment option for glaucoma patients. IOP lowering was successfully achieved in NTG patients with complete success in 70% of the patients. In our study, no significant differences were recorded in-between 90° and 120° of treated trabecular meshwork.

Comparison of the results of Ex-PRESS® surgery for primary open-angle glaucoma between high and low preoperative intraocular pressure

PURPOSE

To compare surgical outcomes of Ex-PRESS® (EXP) surgery for primary open-angle glaucoma (POAG) between low preoperative intraocular pressure (IOP) and high preoperative IOP.

METHODS

This was a retrospective non-randomized study. Seventy-nine POAG patients who underwent EXP surgery and were followed for > 3 years were included. Patients with a preoperative IOP of ≦ 16 mmHg and > 16 mmHg with tolerant glaucoma medications were defined as the low IOP group and the high IOP group, respectively. We compared the surgical outcomes, postoperative IOP and number of glaucoma medications. Success was defined as a postoperative IOP of ≦ 15 mmHg and a reduction of > 20% from the preoperative IOP to the postoperative IOP.

RESULTS

EXP surgeries significantly decreased IOPs from 13.2 ± 2.0 to 9.1 ± 2.9 mmHg in the low IOP group (p < 0.001), and from 22.5 ± 4.8 to 12.5 ± 4.0 mmHg in the high IOP group (p < 0.001). The mean postoperative IOP was significantly low in the low IOP group at 3 years (p = 0.0008). Success rates compared using the Kaplan-Meier survival curve were not significantly different (p = 0.449).

CONCLUSIONS

EXP surgery was useful for POAG patients with a low preoperative IOP.

The Japan Glaucoma Society guidelines for glaucoma 5th edition

We are pleased to bring you the 5th edition of the Glaucoma Clinical Practice Guidelines. Clinical practice guidelines are based on evidence (scientific grounds). It is a document that presents the treatment that is the most appropriate for the patient. "Glaucoma Clinical Guidelines" was first published in 2003. This was the first guideline for glaucoma treatment in Japan. The principle of glaucoma treatment is to lower intraocular pressure. Means for lowering intraocular pressure includes drugs, lasers, and surgery; Glaucoma is a disease that should be considered as a complex syndrome rather than a single condition. Therefore, the actual medical treatment is not as simple as one word. This time we set the Clinical Questionnaire with a focus on glaucoma treatment. We hope that you will take advantage of the 5th edition.

Trabeculectomy: Does It Have a Future?

The trabeculectomy (TRAB) procedure has undergone various modifications to increase the long-term surgical success and safety profiles. The main issues with TRAB include short and long-term complications, that are more common with the concomitant use of anti-fibrotic agents. While many surgeons have predicted the demise of trabeculectomy amidst newer non-penetrating glaucoma surgeries, it is still the gold standard procedure for patients with an advanced or rapidly progressing disease and for those patients who need very low intraocular pressures. This review article is unique in summarizing the evolution of trabeculectomy and its efficacy compared to neoteric shunt procedures while trying to predict if trabeculectomy has a future in the modern surgical world. We have compared the outcomes and complications of trabeculectomy to all the surgical procedures available to date and have tried to evolve an algorithm to help surgeons to decide on their preferred technique.

Prospective 12-month outcomes of combined iStent inject implantation and phacoemulsification in Asian eyes with normal tension glaucoma

BACKGROUND

Glaucoma is the leading cause of irreversible blindness. Normal tension glaucoma (NTG) is a subset of open-angle glaucoma, demonstrating glaucomatous optic nerve damage in the absence of raised intraocular pressure (IOP). NTG is more prevalent in Asian populations. While generally slow-progressing, NTG may be associated with significant central visual field loss. In recent years, minimally invasive glaucoma surgery has been added to the armamentarium of glaucoma surgery. This prospective study aims to evaluate 12-month surgical outcomes of combined iStent inject (Glaukos Corporation, Laguna Hills, CA) implantation and phacoemulsification in Asian eyes with NTG.

METHODS

This is a prospective, single-centre case series of 30 eyes followed up until 12 months after surgery. Outcome measures included IOP, number of glaucoma medications, best-corrected visual acuity (BCVA) and intra and postoperative complications.

RESULTS

Mean age of subjects was 73.1 ± 6.3 years. Majority were ethnic Chinese (n = 27, 90%). Baseline medicated mean IOP was 13.8 ± 2.4 mmHg and mean number of glaucoma medications was 1.3 ± 0.7. Mean Humphrey visual field mean deviation was - 13.7 ± 7.6. The mean IOP reduction at all timepoints from postoperative month (POM) 3 onwards was statistically significant (all P < 0.05), with mean reduction of 1.2 mmHg (95% CI: 0.1-2.2, P = 0.037) by POM12. There was statistically significant reduction in mean number of medications from postoperative day (POD) 1 onwards (all P < 0.05), with mean decrease of 1.0 medication (95% CI: 0.9-1.1, P < 0.001) by POM12. By POM12, 25 (83.3%) eyes were medication-free. Three (10%) eyes had stent occlusion by iris requiring laser iridoplasty. One eye had gross hyphema which resolved on conservative management before POM1. Mean BCVA improved from the baseline 0.3 ± 0.3 logMAR to 0.1 ± 0.1 logMAR postoperatively (P < 0.001). There were no major adverse or sight-threatening events. No eyes required further glaucoma surgery during the 12-month follow-up period.

CONCLUSION

Asian eyes with NTG which underwent combined iStent inject implantation and phacoemulsification demonstrated a significant and sustained reduction in IOP and glaucoma medications, up to 12 months postoperatively.

Trabeculectomy With Antimetabolite Agents for Normal Tension Glaucoma: A Systematic Review and Meta-Analysis

Background

Evidence regarding the impact on visual field (VF), intraocular pressure (IOP), and antiglaucoma medications from trabeculectomy with antimetabolites for normal tension glaucoma (NTG) is conflicting because of insufficient study sample sizes. The aim of this study is to systematically assess VF progression rate, IOP control and antiglaucoma medication use after trabeculectomy with antimetabolites for progressing NTG.

Methods

We searched published articles on PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials from database inception to March 21, 2022. We selected studies that reported VF data before and after trabeculectomy with antimetabolite agents for NTG. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guidelines. Data were extracted by 2 independent reviewers, and a random-effects model was employed for the meta-analysis. Study outcomes were VF progression rates measured using the pooled mean deviation (MD) slope, changes in antiglaucoma medications, and IOP. Subgroup analyses of the MD slope according to mean age (over or under 65 years), baseline MD (over or under –12 dB), and baseline IOP (over or under 15 mmHg) were performed to determine the results’ robustness.

Results

We included 7 retrospective observational studies (Japan: 6 studies, United States: 1 study) comprising a total of 166 eyes. Mean preoperative VF MD slopes ranged from –0.52 to –1.05 dB/year. The meta-analysis demonstrated significant MD slope improvement after trabeculectomy (pooled mean difference: 0.54 dB/year, 95% CI: 0.40 to 0.67, I² = 9%). Mean age, baseline MD, and baseline IOP subgroup analyses revealed MD slope results were consistent with those of the main analyses. The mean IOP (pooled mean difference: –5.54 mmHg, 95% CI: –6.02 to –5.06, I² = 0%) and mean number of antiglaucoma medications (pooled mean difference: –1.75, 95% CI: –2.97 to –0.53, I² = 98%) significantly decreased after trabeculectomy. The most frequently reported early complications after trabeculectomy were hypotony, hyphema, and shallow anterior chamber.

Conclusion

This systematic review and meta-analysis indicated that trabeculectomy with antimetabolites is beneficial for progressing NTG; it preserves visual function by alleviating the MD slope and reducing antiglaucoma medication use. However, several post-trabeculectomy complications should be monitored.

Surgical Advancement of Tenon's Layer During Trabeculectomy Improves Bleb Morphology

Trabeculectomy surgery remains the gold standard incisional glaucoma surgical procedure in many practices, particularly for patients requiring intraocular pressure (IOP) in the low teens or below. However, trabeculectomy surgery is associated with complications including leakage, over filtration, or fibrosis of the surgical bleb. Morphology of the surgical bleb is an important predictor of surgical success defined as long-term IOP reduction with minimal to no complications. There have been many, often subtle, variations in the surgical technique in hopes of improving long-term IOP reduction. However, fewer changes have been implemented specifically to modify bleb morphology. In our surgical practice, we began performing a thorough dissection and advancement of Tenon's layer with incorporation into the conjunctival closure in a 2-layered manner. This technique allowed flow of aqueous to a delineated potential space between sclera and Tenon's layer. Our clinical observations were improved bleb morphology characterized by diffuse, low-lying blebs with nonischemic overlying conjunctiva compared with those performed with a more traditional trabeculectomy technique. Since we incorporated this change into our practice at a defined time, we have a small number of patients in our practice that had a more traditional trabeculectomy technique in the fellow eye. Therefore, in our surgical practice, a small number of patients had trabeculectomy in 1 eye before implementation of this new technique, and then had trabeculectomy in the fellow eye after this technique was adopted, providing opportunity for comparison of bleb morphology with and without Tenon advancement. In series we present two representative, index cases and describe our surgical technique.

Ex-PRESS® surgery versus trabeculectomy for primary open-angle glaucoma with low preoperative intraocular pressure

PURPOSE

To compare surgical outcomes between Ex-PRESS® surgery (EXP) and trabeculectomy (Trab) for primary open-angle glaucoma (POAG) with low preoperative intraocular pressure (IOP).

PATIENTS AND METHODS

This was a retrospective non-randomized study. We included POAG patients with preoperative IOP ≤ 16 mmHg who were taking tolerance glaucoma medications. We compared the surgical outcomes, postoperative IOP, number of glaucoma medications, reduction rate of corneal endothelial cell density (ECD), visual acuity, and postoperative complications between POAG patients who underwent EXP (34 eyes) or Trab (38 eyes) and could be followed up for > 2 years.

RESULTS

Both surgeries significantly decreased the IOP (p < 0.001): At 2 years, EXP provided decreases from 13.4 ± 2.3 to 10.2 ± 3.1 mmHg, and Trab provided decreases from 13.5 ± 2.0 to 8.9 ± 3.2 mmHg. No significant differences were observed in the postoperative IOP (p = 0.076), number of postoperative medications (p = 0.263), success rate (p = 0.900), reduction rate of ECD (p = 0.410), or difference in visual acuity (p = 0.174). The reduction rate of IOP was significantly high in the Trab group (p = 0.047).

CONCLUSIONS

Both surgeries significantly decreased IOP and were useful surgical methods for low-IOP glaucoma. Our results suggest that trabeculectomy can decrease IOP more than Ex-PRESS surgery but might have more complications.

Seasonal Variation and Trend of Intraocular Pressure Decrease Over a 20-Year Period in Normal-Tension Glaucoma Patients

PURPOSE

To investigate the trend of seasonal variation of intraocular pressure (IOP) in patients with normal-tension glaucoma over a 20-year period by retrospectively analyzing the Kyoto Prefectural University of Medicine Glaucoma Registry database as real-world data.

DESIGN

Retrospective cohort study.

METHODS

Data points (n = 49,007) were extracted retrospectively from the medical records of 1774 patients with normal-tension glaucoma (665 male patients and 1109 female patients; mean ± SD age was 59.8 ± 14.4 years; and mean ± SD observation period was 5.6 ± 4.4 years) seen over the 20-year period. We first calculated the mean IOP from all available data of each month from January 1997 through December 2016. The data were then categorized into 5 groups of 4 consecutive years each (1997-2000, 2001-2004, 2005-2008, 2009-2012, and 2013-2016) and the mean IOP of each month within the group was calculated. Seasonal variations of IOP over the 20-year study period and in the 5 consecutive groups were then investigated via nonlinear multiple regression analysis.

RESULTS

A continuous decrease of IOP was detected throughout the 20-year period (P < .001), with distinct seasonal variation. The annual mean ± SD IOP was highest (13.9 ± 2.7 mm Hg) in the oldest group (1997-2000), with a gradual decrease in each subsequent group, finally becoming lowest (12.3 ± 2.7 mm Hg) in the most recent group (2013-2016) (P < .001), and all of them were accompanied by distinct seasonal variation (P < .001).

CONCLUSIONS

Based on the Kyoto Prefectural University of Medicine Glaucoma Registry real-world longitudinal data, our findings revealed a continuous decrease and distinct seasonal variation of IOP in patients with normal-tension glaucoma throughout the 20-year study period.

Central visual field change after fornix-based trabeculectomy in Japanese normal-tension glaucoma patients managed under 15 mmHg

PURPOSE

To investigate how the central visual field would be changed after fornix-based trabeculectomy with mitomycin C in Japanese normal-tension glaucoma (NTG) patients monitored for more than 10 years including before surgery.

METHODS

This is a retrospective cohort study. We identified twenty-eight eyes of 28 NTG cases regularly monitored for more than 5 years and examined static visual field (VF) tests for more than five times before and after fornix-based trabeculectomy (including combined surgery). Based on preoperative data for 6.3 years, we evaluated postoperative changes for 6.0 years in 10-2 VF and 30-2 VF.

RESULTS

Six patients were male and 22 females, the mean age was 57.9 years, and the mean deviation was - 13.7 decibels. After surgery, mean IOP decreased from 13.9 to 9.0 mmHg (P ≤ 0.01), and medication score also did. The rate of 10-2 VF deterioration was significantly suppressed from - 1.0 dB/year preoperatively to - 0.4 dB/year postoperatively (P ≤ 0.01). And when 30-2 VF was divided into six relevant sectors, the rate of deterioration at cecocentral and arcuate areas of the superior hemifield was suppressed postoperatively (P ≤ 0.01 and P = 0.042, respectively).

CONCLUSION

Based on long-term preoperative data, a significant positive change in 10-2 VF was observed after fornix-based trabeculectomy with mitomycin C in Japanese NTG patients with a mean IOP of 13.9 mmHg. Central vision could be expected to be maintained for NTG patients even if its preoperative IOP is low after successful trabeculectomy.

Safety and efficacy of microinvasive glaucoma surgery with cataract extraction in patients with normal-tension glaucoma

This study assesses the safety and efficacy of microinvasive glaucoma surgery (MIGS) with cataract extraction in patients with normal-tension glaucoma (NTG). In our sample of 45 NTG patients, mean intraocular pressure (IOP) decreased from 13.7 to 12.3 mmHg at 2.5 years, and mean medication burden decreased from 2.0 to 1.1 at 1.5 years. For success defined as IOP reduction ≥ 30% from baseline IOP with medication burden reduction from preoperative levels, success probability was 5.4% at 1.5 years. For success defined as medication burden reduction with an IOP reaching goal IOP as determined by the glaucoma specialist, success probabilities were 67.2% at 1.5 years and 29.4% at 2.5 years. At the last follow-up visit, eyes with two MIGS procedures with different mechanisms of action achieved successful medication reduction 68.8% of the time versus 35.7% achieved by a single MIGS procedure (p = 0.052). At their last visit, visual acuity was unchanged or improved in all eyes (100%). MIGS with cataract surgery results in modest reductions in IOP and medication burden in NTG patients, which may lead to lower costs and better therapeutic compliance. A combination of two MIGS procedures with different mechanisms of action may potentially be more effective in reducing medication burden than a single MIGS procedure in NTG patients. Further research is necessary to ascertain whether MIGS for NTG patients may help decrease medication burden while helping achieve goal IOP.

Evaluation of fornix-based trabeculectomy outcomes in Japanese glaucoma patients based on concrete long-term preoperative data

PURPOSE

To investigate the outcomes of fornix-based trabeculectomy in Japanese patients with glaucoma based on more than five years of preoperative data.

STUDY DESIGN

Retrospective case series METHODS: This study consisted of 35 eyes of 35 Japanese glaucoma patients (mean age: 60.6, standard deviation (SD) 11.5 years) who received initial fornix-based trabeculectomy from a single ophthalmology clinic, with one or more reliable visual field test results per year from at least five years before and after the surgery. Measurements included postoperative mean intraocular pressure (IOP), standard deviation of IOP, medication scores, mean deviation slope, and total deviation slope were evaluated based on preoperative data. The relationship between mean IOP, SD-IOP and the visual field (VF) deterioration speed was also analysed.

RESULTS

The mean follow-up period before surgery was 6.15 (SD 0.97) years and post surgery it was 5.95 (SD 0.63) years. The preoperative mean IOP of 14.6 (SD 2.3) mmHg significantly decreased to 9.2 (SD 2.2) mmHg (P <.001). The preoperative medication score 2.7 (SD 0.5) significantly decreased to 0.1 (SD 0.4, P <.001). The preoperative MD slope of -0.52 (SE 0.047) dB/year significantly improved to -0.31 (SE 0.14) dB/year (P <.01), with improvement in the superior hemifield (P ≤.018). Inferior hemifield (P >.10) did not follow the trend. Neither mean IOP nor SD-IOP correlated with the VF deterioration speed.

CONCLUSIONS

Fornix-based trabeculectomy is an acceptable procedure for initial surgical management of glaucoma, especially for maintenance of superior VF.

Effective treatment of a normal-tension glaucoma patient with bilateral ab externo XEN Gel Stent implantation

Purpose

To provide the first report of effective use of bilateral XEN Gel Stent implantation using an ab externo open-conjunctival approach designed to improve bleb function and meet the uniquely low intraocular pressure requirements of a Japanese patient with normal-tension glaucoma refractory to topical medical therapy.

Observations

A 54-year-old phakic Japanese woman with severe normal-tension glaucoma on maximally tolerated medical therapy of four topical agents presented with above-goal intraocular pressures and new medication intolerances. She underwent bilateral ab externo open-conjunctival XEN Gel Stent implantation with tenectomy and sub-Tenon's injection of 40μg of mitomycin-C, which resulted in reduction of intraocular pressures by 41.2 and 28.6% to 10 and 10 mmHg in the right and left eyes, respectively at the most recent visit. Postoperatively, a diffuse filtering bleb with good morphology developed in both eyes. The procedure has so far allowed for complete cessation of all four topical medications for up to eight months following surgery without any serious complications.

Conclusions

This case illustrates the potential of Xen Gel Stent implantation through an ab externo, open-conjunctival approach to be an effective, simple alternative to trabeculectomy to meet the unique low-pressure requirements of normal-tension glaucoma patients with practical and safety benefits of a micro-invasive approach.

Management of the glaucoma patient progressing at low normal intraocular pressure

PURPOSE OF REVIEW

Patients with glaucoma with disease progression despite low or normal intraocular pressure (IOP) present special challenges to the treating clinician. Treatment goals may depend on whether patients have apparent low IOP with concurrent treatment or have low IOP at baseline without treatment. We review the diagnostic and therapeutic approaches to these patients.

RECENT FINDINGS

Apparent progression at low IOP should start with confirmation of IOP, made easier by devices enabling patient home self-tonometry. Suspected visual field progression should be confirmed by repeat testing prior to advancement of therapy. Trabeculectomy remains the most effective surgical method of achieving long-term success, particularly when there is a low starting IOP. Drainage tube implantation or the use of novel micro-incisional non-bleb-forming procedures are less likely to be successful in achieving low IOP goals.

SUMMARY

Diagnostic testing is important in confirming progressive glaucomatous disease at low IOP levels. The most effective way of slowing the progression of glaucoma in a patient with low IOP is to lower the IOP further, sometimes to single digit levels, which is most often achievable with trabeculectomy.

One year structural and functional glaucoma progression after trabeculectomy

We evaluated the changes in visual field mean deviation (VF MD) and retinal nerve fibre layer (RNFL) thickness in glaucoma patients undergoing trabeculectomy. One hundred patients were examined with VF and spectral-domain optical coherence tomography (OCT) before trabeculectomy and 4 follow-up visits over one year. Linear mixed models were used to investigate factors associated with VF and RNFL. VF improved during the first 3 months of follow-up (2.55 ± 1.06 dB/year) and worsened at later visits (−1.14 ± 0.29 dB/year). RNFL thickness reduced by −4.21 ± 0.25 µm/year from 1st month of follow-up. Eyes with an absence of initial VF improvement (β = 0.64; 0.30–0.98), RNFL thinning (β = 0.15; 0.08–0.23), increasing intraocular pressure (IOP; β = −0.11; −0.18 to −0.03) and severe glaucoma (β = −10.82; −13.61 to −8.02) were associated with VF deterioration. Eyes with VF deterioration (β = 0.19; 0.08–0.29), increasing IOP (β = −0.09; −0.17 to −0.01), and moderate (β = −6.33; −12.17 to −0.49) or severe glaucoma (β = −19.58; −24.63 to −14.52) were associated with RNFL thinning. Changes in RNFL structure and function occur over a 1-year follow-up period after trabeculectomy. Early VF improvement is more likely to occur in patients with mild/moderate glaucoma, whereas those with severe glaucoma show greater decline over one year. Our findings indicate that progression is observable using OCT, even in late-stage glaucoma.

Effectiveness of trabeculectomy with mitomycin C for glaucomatous eyes with low intraocular pressure on treatment eye drops

PURPOSE

To examine the efficacy and safety of current trabeculectomy with mitomycin C in Japan for glaucomatous eyes with low intraocular pressure (IOP).

METHODS

Two hundred ninety-four eyes of 294 patients with IOP ≤21 mmHg before surgery were studied; all patients were participants in the Collaborative Bleb-related Infection Incidence and Treatment Study (CBIITS), a multicentre, prospective, cohort study conducted at 34 ophthalmological institutions throughout Japan. All eyes had an intraocular pressure ≤ 21 mmHg and had undergone trabeculectomy alone or phacotrabeculectomy. Two success criteria were used: Criterion A comprised 20% reduction of baseline IOP and Criterion B comprised 30% reduction of baseline IOP. The primary outcome was the success rate for each of these criteria.

RESULTS

The qualified success rates were 87.3% for Criterion A and 42.0% for Criterion B at 5 years. Mean IOP was significantly reduced, from 16.7 ± 2.7 to 11.6 ± 4.0 mmHg at 5 years after trabeculectomy (p < 0.0001); the number of anti-glaucoma medications significantly decreased from 2.7 ± 1.1 to 1.0 ± 1.2 (p < 0.0001) at 5 years after the surgery. Three or more trabeculectomies, and needling were related to increased risk of failure. Incidences of postoperative hyphema, infection, shallow anterior chamber and bleb leakage were 2.4%, 2.4%, 2.0% and 3.4%, respectively.

CONCLUSIONS

This study showed that trabeculectomy with mitomycin C is an effective procedure with few surgical complications for reducing IOP in patients, even if preoperative IOP was within the normal range.

The Sustained Release of Tafluprost with a Drug Delivery System Prevents the Axonal Injury-induced Loss of Retinal Ganglion Cells in Rats

PURPOSE

To investigated whether a new drug delivery system (DDS) could enable the controlled release of tafluprost and suppress retinal ganglion cell (RGC) death in rats after optic nerve transection (ONT).

METHODS

A DDS containing 0.04%, 0.20% or 1.00% tafluprost, or vehicle, was injected intravitreally in 8-12-week-old male Sprague-Dawley rats 7 days before ONT, and the retinas were extracted 7 days after ONT. For comparison, eye drops containing 0.0015% tafluprost or vehicle were used once a day. The extracted retinas were analyzed with liquid chromatography-tandem mass spectrometry, immunohistochemistry and western blotting.

RESULTS

The level of tafluprost acid in the groups that received the 0.20% and 1.00% tafluprost DDSs was stable, and higher than the maximum concentration in the eye drop group, even after 14 days. In the retinas treated with the 1.00% tafluprost DDS, the active form of the drug had a high concentration (~50 times higher than eye drops), but no significant IOP difference compared with its vehicle in this study. The 1.00% tafluprost DDS group also had less cleaved α-fodrin and fewer c-Jun-positive cells than the vehicle DDS group.

CONCLUSIONS

This study found that a newly developed DDS allowed the controlled release of tafluprost and prevented the loss of RGCs after ONT IOP independently. The duration of drug action on the target site was longer with a tafluprost DDS than with topical instillation and should therefore reduce problems related to lack of patient compliance. This system may also enable new treatments to prevent RGC degeneration in diseases such as glaucoma.

Attaining Intraocular Pressure of ≤10 mm Hg: Comparison of Tube and Trabeculectomy Surgery in Pseudophakic Primary Glaucoma Eyes

PURPOSE

The aim of this study is to evaluate whether trabeculectomy with antimetabolites or glaucoma drainage device (GDD) surgery is more likely to achieve an intraocular pressure (IOP) ≤10 mm Hg.

DESIGN

Retrospective, nonrandomized, cohort study of pseudophakic, primary glaucoma patients.

METHODS

53 pseudophakic patients underwent trabeculectomy and 65 received GDD at the University of Florida by one surgeon between 1993 and 2015. The main outcome measures were mean IOP and percentage of patients obtaining an IOP ≤10 mm Hg for up to 5 years postoperatively. A subgroup undergoing a first time glaucoma surgery was also analyzed because there were more redo glaucoma procedures in the GDD group.

RESULTS

Over 5 years, the mean annual IOP for the trabeculectomy eyes was between 6.9 and 7.8 mm Hg on an average of 0.2 medications, and that for GDD eyes was between 11.4 and 12.1 mm Hg on a mean of 1.6 to 1.9 medications (P < 0.002). A significantly higher percentage of trabeculectomy eyes than GDD eyes achieved a pressure of ≤10 mm Hg, for years 1 to 4 (P < 0.05). Visual acuity (VA) change was not statistically different between the groups, both for mean logMAR acuity and percentage of patients that lost ≥2 Snellen lines. Complication rates were similar between the groups. Postoperative VA change was similar for eyes achieving low IOP ≤5 mm Hg and those eyes with an IOP ≥10 mm Hg.

CONCLUSIONS

Trabeculectomy provided significantly lower IOP for 5 years postoperatively in pseudophakic primary glaucoma patients, and was more likely to achieve an IOP ≤10 mm Hg.