Long-term results of deep sclerectomy in normal-tension glaucoma

[Why trabeculectomy is better than its reputation]

BACKGROUND

Trabeculectomy (TE) remains one of the most frequently performed glaucoma procedures. This surgery enables sufficient reduction of intraocular pressure (IOP) and freedom from using eye drops; however, complication management and time-consuming postoperative care make many ophthalmic surgeons reluctant to include TE in their treatment regimen.

AIM

This review presents the value of TE compared to other forms of filtering and nonfiltering glaucoma surgery.

CONCLUSION

The use of TE is still the most effective method for lowering IOP and in comparison to other forms of glaucoma surgery in most cases enables freedom from eye drops with a subsequent high quality of life. Postoperative complications occur more frequently, but usually heal spontaneously or can be treated adequately and safely by surgery; however, TE requires intensive postoperative care, which should not be neglected. Repeated surgery due to insufficient IOP reduction is less frequent compared to other forms of glaucoma surgery.

Outcomes of Deep Sclerectomy following Failed XEN Gel Stent Implantation in Open-Angle Glaucoma: A Prospective Study

Background: The purpose of this study is to evaluate the outcome of deep sclerectomy (DS) as a secondary procedure following failed ab-interno XEN gel stent implantation in patients with open-angle glaucoma. Methods: Prospective, single-center, non-randomized, interventional study. Consecutive eyes that underwent mitomycin C (MMC) augmented XEN gel stent surgery, with uncontrolled intraocular pressure (IOP) or signs of disease progression, were included to undergo MMC-augmented DS. Primary efficacy outcome was surgical success, defined as complete when the unmedicated IOP was 12 mmHg or less, or 15 mmHg or less and 20% lower than at the timing of XEN failure and defined as qualified when the IOP fulfilled the same conditions with fewer medications than before deep sclerectomy. Secondary measures were mean reduction in IOP and in the number of medications, and the rates of complications. Results: Seventeen eyes were enrolled with a mean age of 72.1 ± 8.2 years (66.7% women). The mean follow-up was 20.1 ± 4.9 months, with more than 12-month data available from 15 eyes. Following DS, IOP decreased significantly from 22.6 ± 5.3 mmHg to 12.3 ± 5.5 (45.6%; p < 0.001). Antiglaucoma medications dropped from 1.1 ± 0.9 to 0.3 ± 0.7. Complete success was obtained in 40% of eyes using the threshold of 12 mmHg or less and a 20% decrease of IOP, and in 60% using the 15 mmHg or less threshold. Adverse events were observed in 20% of eyes (bleb leakage (13.3%); hypotony (6.7%)). No cases of choroidal detachment or hypotony maculopathy were reported. Conclusions: Failed XEN gel stent implantation does not seem to negatively affect the safety and efficacy of subsequent deep sclerectomy surgery.

Reintervention rate in glaucoma filtering surgery: A systematic review and meta-analysis

PURPOSE

Reintervention rate is an important factor impacting on patients, surgeons, and society. To date, only a few studies have focused on this topic. For this reason, a systematic review and meta-analysis was undertaken to assess the reintervention rate after glaucoma filtering surgery.

MATERIALS AND METHODS

Prospective studies reporting the reintervention rate after glaucoma filtering surgery and with at least 12 months of follow-up were systematically searched on PubMed, Medline and Embase databases. The primary outcome was the total reintervention rate following surgery. Secondary outcomes were: the rate of manipulation, in-clinic and in-operating room reintervention; the reintervention rate for intraocular pressure (IOP) control and for complications; demographic, clinical and surgical variables associated with reintervention rate.

RESULTS

Ninety-three studies with a total of 8345 eyes were eligible. The total reintervention rate was 1.84 (95% CI 1.57-2.13), with a lower rate for Baerveldt (0.53, 95% CI 0.29-0.83) and Preserflo (0.60, 95% CI 0.15-1.29), and a higher rate for Xen (4.26, 95% CI 2.59-6.31). The manipulation rate was 0.99 (95% CI 0.77-1.23), the in-clinic reintervention rate was 0.08 (95% CI 0.05-0.12) and the in-operating room reintervention rate was 0.28 (95% CI 0.22-0.35). The reintervention rate for IOP control was 1.26 (95% CI 1.04-1.51) and the reintervention rate for complications was 0.27 (95% CI 0.21-0.35).

CONCLUSIONS

All types of surgery presented a total reintervention rate similar to the overall findings, except studies on Baerveldt and Preserflo Microshunt, with a lower rate, and Xen, with a higher rate. None of the variables evaluated were found to be directly associated with the explored outcomes.

Statin use and the reoperation rates in glaucoma filtration surgery - population-based cohort study

PURPOSE

To examine the association of systemic statin therapy and reoperation rate after glaucoma filtration surgery (GFS).

METHODS

This is a population-based, historic cohort study of 2705 eyes undergoing GFS in Finland between July 2009 and December 2016. GFSs were identified from national administrative healthcare registers. Baseline sociodemographic and health characteristics were documented. Reoperation rates of GFS subgroups were analysed, with statin users compared to non-users. The outcomes were modelled using a Poisson regression model adjusted for age, sex, education, statin use, chronic comorbidities, and cataract surgery with incident rate ratios (IRR) as the main outcome measure.

RESULTS

The cohort contained 2263 subjects with open-angle glaucoma (OAG), 823 men and 1440 women. Surgery was performed on 2705 eyes. First documented procedures: deep sclerectomy (DS) (n = 1601), trabeculectomy (TRE) (799) and glaucoma drainage device (GDD) implantation (305) respectively. In total, 438 secondary operations were performed during the 7.5-year (median 2.25 years) follow-up period. The reoperation rates were 19% after DS, 12% after TRE, and 13% after GDD. Of the surgical procedures, 32% were performed on eyes of patients receiving statin therapy. Statin users showed no difference in reoperation rates (IRR 1.06, CI 0.82-1.37). In subgroups, no difference was observed in the reoperation rates adjusted with statin use after filtration surgery (DS, TRE) (IRR 1.06, CI 0.8-1.40) or GDD implantation (0.57, CI 0.20-1.63).

CONCLUSION

Systemic statin therapy among surgically treated OAG patients had no impact on secondary surgery rates following DS, TRE or GDD implantation.

[Anti-scarring effect of rapamycin following filtering surgery in rabbit eyes]

OBJECTIVE

To study the effect of rapamycin on scar formation in rabbit eyes following filtering operation and explore the possible mechanism.

METHODS

Ninety-six healthy adult rabbits were subjected to trabeculectomy of the left eye and subsequently randomly divided into 4 groups (n=24) for treatment with castor oil (control) or rapamycin (1%, 3%, or 5%) eye drops of the operated eyes 4 times a day. The morphology and function of the filtering blebs of the rabbits were compared at 7, 14, 21 and 28 days after the operation; at each of the time points, 6 rabbits from each group were euthanized for detection of expressions of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA) in the tissues in the surgical area using immunohistochemistry. Cultured rabbit subconjunctival fibroblasts (RTFSs) were treated with different concentrations of rapamycin (0.06, 0.25, 1, and 4 mg/L) and the cell apoptosis was detected using flow cytometry.

RESULTS

In the first, second and third weeks after the operation, the rate of functional follicle formation was significantly higher in the 3 rapamycin groups than in the control group (P < 0.05), and the number of α- SMA-positive fibroblasts decreased over time in the 3 rapamycin groups. In cultured RTFSs, treatment with rapamycin at different concentrations resulted in increased apoptosis of the cells, and rapamycin above 0.25 mg/L significantly increased the cell apoptosis in a dose-dependent manner.

CONCLUSIONS

Rapamycin can inhibit hyperplasia of the filtering passage tissue, helps to preserve the functional filtering blebs and prolong their life span, and induces apoptosis of RTFS.

Can postoperative dexamethasone nanoparticle eye drops replace mitomycin C in trabeculectomy?

PURPOSE

Compare (a) nonmitomycin C (MMC) trabeculectomy and 1.5% dexamethasone nanoparticle (DexNP) eye drops postoperatively with (b) trabeculectomy with MMC and Maxidex^® eye drops postoperatively.

METHODS

Randomized prospective single masked clinical trial with 20 patients with primary open-angle glaucoma undergoing primary trabeculectomy. The study group consisted of 10 patients without MMC intraoperatively and postoperative DexNP eye drops, and the control group consisted of 10 patients treated with MMC intraoperatively and postoperative Maxidex^® . The drops were tapered out over 8 weeks. The main outcome measures were as follows: rates of complete success, that is intraocular pressure (IOP) within target pressures at different time-points without IOP-lowering medication, or reoperation. Secondary outcome measures included the following: relative success rate (with IOP-lowering medications), number of glaucoma medications and reoperations. Patients were followed for 36 months.

RESULTS

Both groups showed similar postoperative course and IOP reduction. Intraocular pressures (IOPs) in the DexNP group and in the control group were 25.6 and 24.4 mmHg, respectively, at baseline. Intraocular pressures (IOPs) were reduced to 13.2 and 14.5 mmHg at 12 months, 11.7 and 12.6 mmHg at 24 months and 11.7 and 12.1 mmHg at 36 months, respectively. There were no statistically significant differences between the groups in absolute (p = 0.36) or relative (p = 1.0) success rates, number of medications (p = 0.71) or reoperations (p = 1.0) between the groups at any time-point.

CONCLUSIONS

DexNP eye drops are effective postoperative treatment following trabeculectomy. The potent anti-inflammatory and antifibrotic effect of DexNP may offer an alternative to mitomycin C in glaucoma surgery.

Comparison of early versus late laser goniopuncture following deep sclerectomy for the management of open-angle glaucoma

Purpose

To compare the outcome of early versus late Nd:YAG laser goniopuncture (LGP) after deep sclerectomy with mitomycin C (DSMMC) for open-angle glaucoma (OAG).

Methods

A retrospective study of consecutive OAG eyes that underwent a LGP following DSMMC was recruited between June 2012 and November 2015. Success was defined as intraocular pressure (IOP) less than 21, 18 or 15 mm Hg with a reduction of more than 20% IOP from baseline without (complete success) or with medications (qualified success).

Results

99 eyes with OAG that underwent DSMMC were recruited into the study. Of these, 49 eyes (49.49%) had undergone LGP post-DSMMC. IOP was significantly reduced following LGP from 28.4 to 11.8 mm Hg. Comparison of Kaplan-Meier survival curves out to 60 months after LGP showed a trend towards better outcomes in the late LGP group with the only statistically significant difference noted for qualified success with IOP target <15 mm Hg. Complications were few with no difference noted between early and late LGP groups.

Conclusion

There appears to be a trend towards late LGP being more effective after DSMMC when compared with early LGP; this however was not significant. This study corroborates previous published data confirming LGP is an effective and safe procedure for lowering IOP post-DSMMC procedure.

High-Frequency Deep Sclerotomy, A Minimal Invasive Ab Interno Glaucoma Procedure Combined with Cataract Surgery: Physical Properties and Clinical Outcome

Background: The efficiency and safety of primary open-angle glaucoma with high-frequency deep sclerotomy (HFDS) combined with cataract surgery has to be investigated. Methods: Right after cataract surgery, HFDS was performed ab interno in 205 consecutive patients with open angle glaucoma. HFDS was performed with a custom-made high-frequency disSection 19 G probe (abee tip 0.3 × 1 mm, Oertli Switzerland). The bipolar current with a frequency of 500 kHz is applied. The nasal sclera was penetrated repetitively six times through the trabecular meshwork and consecutively through Schlemm’s canal. Every time, a pocket of 0.3 mm high and 0.6 mm width was created. Results: Mean preoperative intraocular pressure (IOP) was 24.5 ± 2.1 mmHg (range 21 to 48 mmHg). After 48 months, the follow up average IOP was 15.0 ± 1.7 mmHg (range 10 to 20 mmHg). Postoperative IOP has been significantly reduced compared to preoperative IOP for all studied cases (p < 0.001). After 48 months, the target IOP less than 21 mmHg reached in 84.9%. No serious complications were observed during the surgical procedure itself and in the postoperative period. Conclusions: HFDS is a minimally invasive procedure. It is a safe and efficacious surgical technique for lowering IOP combined with cataract surgery.

Influence of glaucoma surgery on visual function: a clinical cohort study and meta-analysis

Purpose

To determine the cost (loss of visual function associated with the procedure) and benefit (long‐term preservation of the visual field) of glaucoma surgery.

Methods

We included 100 patients who underwent glaucoma surgery (Baerveldt glaucoma implant [BGI], n = 61; trabeculectomy [TE], n = 39). Preoperatively, the median (interquartile range [IQR]) standard automated perimetry mean deviation (MD) was −12 (−16 to −6) dB. We analysed the change in visual acuity (BCVA) and MD due to the procedure and, in a subset with at least 5 years of perimetric follow‐up both pre‐ and postoperatively (n = 20), the change in rate of progression (ROP; time rate of change in MD). For the surgery‐induced change in ROP, we also performed a meta‐analysis including the current and previously published studies. From the surgery‐induced decrease in MD and change in ROP, we calculated the average postoperative duration needed for the benefit to surpass the cost.

Results

Mean (standard deviation) MD decline was 1.3 (2.7) and 1.0 (2.3) dB for BGI (p < 0.001) and TE (p = 0.009), respectively; no significant surgery‐induced changes in BCVA were found (p = 0.08 and p = 0.12, respectively). In our study, surgery was associated with a non‐significant deceleration of ROP (from −0.37 [0.52] to −0.15 [0.48] dB/year; p = 0.23). The meta‐analysis, based on eight studies, showed an overall surgery‐induced change in ROP of 0.44 (95% confidence interval 0.25 to 0.64; p < 0.0001) dB/year.

Conclusion

Glaucoma surgery significantly reduces the progression velocity in glaucoma. On average, the benefit of glaucoma surgery surpasses the cost after approximately 1.5 years.

Outcome of Primary Nonpenetrating Deep Sclerectomy in Patients with Steroid-Induced Glaucoma

Purpose

To evaluate the outcome of primary nonpenetrating deep sclerectomy (NPDS) in patients with steroid-induced glaucoma.

Methods

This was a retrospective interventional clinical study that included 60 eyes of 60 steroid-induced glaucoma patients that had undergone NPDS. Patients were followed up for 4 years. Data from the records was retrieved as regards corrected distance visual acuity (CDVA), intraocular pressure (IOP), visual field mean defect (dB), and number of antiglaucoma medications needed if any. Complete success of the surgical outcome was considered an IOP ≤ 21 mmHg with no antiglaucoma medications. Qualified success was considered an IOP ≤ 21 mmHg using antiglaucoma medications.

Results

The mean age was 21.2 ± 8.5 years (ranged from 12 to 35 years). At 48 months, mean IOP was 13.6 ± 2.8 mmHg (range 11-23 mmHg). This represented 60% reduction of mean IOP from preoperative levels. One case had YAG laser goniopuncture. Three cases required needling followed by ab interno revision. Using ANOVA test, there was a statistically significant difference between preoperative and postoperative mean IOP values (P = 0.032). Twelve, 16, and 20 patients required topical antiglaucoma medications at 24, 26, and 48 months postoperative, respectively.

Conclusion

Primary nonpenetrating deep sclerectomy is a safe and an effective method of treating eyes with steroid-induced glaucoma. No major complications were encountered. After 4 years of follow-up, complete success rate was 56.7% and qualified success rate was 70%.