Clinical results of ab interno trabeculotomy using the trabectome for open-angle glaucoma: the Mayo Clinic series in Rochester, Minnesota

Angle-based minimally invasive glaucoma surgery in normal tension glaucoma: A systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis quantitatively examines the efficacy of angle-based minimally invasive glaucoma surgery (MIGS) in normal tension glaucoma (NTG).

METHODS

A literature search was performed on Medline, Embase, PubMed, CINAHL and Cochrane Library from inception until 20 December 2022. Pilot, cohort, observational studies and randomised controlled trials including at least 5 subjects undergoing angle-based MIGS (trabecular-bypass devices, excisional trabeculotomy, goniotomy and ab-interno canaloplasty) for NTG, with or without cataract surgery, were included. Meta-analysis of continuous outcome using the meta routine in R version 2022.12.0+353 was performed to determine mean intraocular pressure (IOP) and anti-glaucoma medication (AGM) reduction post-operatively.

RESULTS

Of the 846 studies initially identified, 15 studies with a pooled total of 367 eyes which underwent combined phacoemulsification and angle-based MIGS were included for final meta-analysis. Outcomes of the iStent were reported in 5 studies, iStent inject in 7 studies, Hydrus Microstent in 1 study, Kahook Dual Blade in 3 studies, and Trabectome in 2 studies. There was significant reduction in both IOP and AGM post-operatively at 6 months (2.44 mmHg, 95%CI: 1.83-3.06; 1.21 AGM, 95%CI: 0.99-1.44), 12 months (2.28 mmHg, 95%CI: 1.71-2.84; 1.18 AGM, 95%CI: 0.90-1.47), 24 months (2.10 mmHg, 95%CI: 1.51-2.68; 1.26 AGM, 95%CI: 0.85-1.68) and 36 months (2.43 mmHg, 95%CI: 1.71-3.15, 0.87 AGM, 95%CI: 0.21-1.53) (all p < 0.05). Subgroup analysis on combined phacoemulsification-iStent inject surgery demonstrated a reduction in both IOP (2.31 mmHg, 95%CI: 1.07-3.56, p < 0.001) and AGM (1.07 AGM, 95%CI: 0.86-1.29, p < 0.001) at 12 months post-operatively.

CONCLUSIONS

Angle-based MIGS combined with phacoemulsification effectively reduces IOP and AGM in NTG eyes for up to 36 months after surgery.

The Effectiveness of Pattern Scanning Laser Trabeculoplasty as an Additional Treatment for the Patients of Open-Angle Glaucoma Receiving Full Ocular Hypotensive Medications

Objectives: Our purpose was to examine the effectiveness of pattern scanning laser trabeculoplasty (PSLT) as an additional treatment for patients of open-angle glaucoma (OAG) receiving maximized ocular hypotensive medications (OHM). Methods: A total of 40 eyes of 33 patients (average age 72.7 ± 10.7 years) who had not previously undergone open glaucoma surgery or laser trabeculoplasty and were treated with maximized OHM between June 2018 and March 2022 were included. A 360-degree PSLT was conducted, and postoperative intraocular pressure (IOP) and survival curves at 1, 3, 6, 9, and 12 months were evaluated. Results: According to the Kaplan-Meier survival analysis, the average survival time was 8.1 months and the survival rate at 12 months was 0.55, with death defined as postoperative IOP reduction of less than 10% or requiring additional treatment. The average survival time was 4.9 months and the survival rate at 12 months was 0.28, with death defined as postoperative IOP reduction of less than 20% or requiring additional treatment. Nine eyes showed increased IOP (three eyes) or worsened visual field (six eyes) during the course and underwent additional open glaucoma surgery. In the 31 eyes which received no additional treatment after PSLT, the mean preoperative IOP was 18.5 ± 3.9 mmHg, which reduced to 15.3 ± 4.1 mmHg (p = 1.62 × 10-6), 15.5 ± 3.4 mmHg (p = 1.51 × 10-5), 15.7 ± 4.0 mmHg (p = 1.75 × 10-5), 14.7 ± 4.38 (p = 2.89 × 10-6), and 15.0 ± 4.0 mmHg (p = 5.74 × 10-9) at 1, 3, 6, 9, and 12 months after PSLT, respectively. The IOP reduction rate one year after PSLT was 18.7%. Of the 31 eyes, 13 (42%) achieved a 20% reduction in IOP compared to the baseline. Conclusions: Adjunctive treatment with PSLT in OAG patients receiving maximized OHM may be effective over 12 months of follow-up.

Effect of Preoperative Trabecular Meshwork Pigmentation and Other Eye Characteristics on Outcomes of Combined Phacoemulsification/Minimally Invasive Glaucoma Surgery

PURPOSE

To investigate associations between pigmentation of the trabecular meshwork (PTM) and other preoperative eye characteristics and outcomes of minimally invasive glaucoma surgery combined with phacoemulsification (Phaco/MIGS).

DESIGN

Retrospective interventional case series.

PARTICIPANTS

Academic glaucoma clinic patients with symptomatic cataract and glaucoma treated with combined Phaco/MIGS.

METHODS

Analyzing preoperative PTM, intraocular pressure (IOP), IOP-lowering medications and visual acuity (VA) data in relation to Phaco/MIGS outcomes.

MAIN OUTCOME MEASURES

Pigmentation of the trabecular meshwork and other preoperative eye characteristics in relation to Phaco/MIGS success defined as postoperative IOP between 5 and 21 mmHg and IOP reduction of ≥ 20% and/or a reduction of ≥ 1 IOP-medications compared to baseline, and final IOP, IOP-lowering medications and VA.

RESULTS

A total of 265 eyes (172 patients, mean age, 73.5 [standard deviation, 10.0], range 35-95 years, male 40.0%) were identified and categorized with high PTM (108 eyes, 40.8%) or low PTM (157 eyes, 59.2%). The high PTM group, compared with the low PTM group, demonstrated higher preoperative IOP (16.7 [standard error 0.4] vs. 15.2 [0.4] mmHg, P = 0.009), included more eyes with primary open-angle glaucoma (POAG, P = 0.03), fewer eyes with normal-tension glaucoma (NTG, P = 0.01), and fewer eyes with mild stage glaucoma (P = 0.001). Compared to baseline, final IOP decreased by 6.5 [2.4]% and 13.4 [3.0]% (P = 0.075) to 13.5 [0.3] mmHg and 13.6 [0.4] mmHg (P = 0.77) in the low and high PTM groups, respectively, and IOP-lowering medications decreased by 34.6 [4.9]% (n = 116) and 18.1 [7.3]% (n = 85), respectively (P = 0.062). Surgical success was 59.9% and 58.3%, respectively (P = 0.87). It was positively associated with higher preoperative IOP (hazard ratio 1.08 [95% confidence interval 1.04-1.12] P < 0.0001) and higher number of preoperative IOP-medications (1.20 [1.05-1.37] P = 0.007), negatively associated with history of selective laser trabeculoplasty (SLT, 0.40 [0.23-0.68] P = 0.0009) and longer axial length (0.87 [0.80-0.94], P = 0.0006), but was not associated with PTM.

CONCLUSIONS

Higher PTM was associated with POAG rather than NTG, with more severe glaucoma and higher preoperative IOP, but not with Phaco/MIGS success. Surgical success was positively associated with higher preoperative IOP and number of IOP-medications and negatively associated with history of SLT and longer axial length. These findings may help guide glaucoma surgeons in surgical planning and patient counseling.

FINANCIAL DISCLOSURE(S)

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

The effect of axial length on the short-term outcomes of cataract surgery combined with ab interno trabeculotomy

PURPOSE

Minimally invasive glaucoma surgery is safer and effective surgical modality for patients with glaucoma. To compare the effect of axial length (AL) on the surgical outcomes of combined cataract surgery and ab interno trabeculotomy (phaco-LOT), a retrospective, non-randomized comparative study was performed.

METHODS

In total, 458 eyes of 458 open-angle glaucoma patients who underwent phaco-LOT and were followed-up without any intervention for at least 6 months were enrolled. All were divided into a long-AL group (AL ≥ 26.0 mm, 123 eyes) and a not-long-AL group (AL < 26.0 mm, 335 eyes). The principal outcomes were the changes in intraocular pressure (IOP) and medication scores. We also sought a correlation between postoperative IOP spike and hyphema.

RESULTS

Significant postoperative reductions in IOP and medication scores were apparent in all subjects. The IOP reductions were significant at all timepoints in the not-long-AL group, but not until 1 month postoperatively in the long-AL group, and the IOP change was significantly lower in the long-AL group from postoperative day 1 to 3 months. On subanalysis of subjects by age, the microhook used, the pre-operative IOP, and the medication score, a significantly higher incidence of IOP spike was observed in the long-AL group in weeks 1 and 2 (both p < 0.05), but this did not correlate with hyphema status, implying that a different mechanism was in play.

CONCLUSION

Phaco-LOT was effective regardless of AL, but the postoperative IOP decrease was lower and the early postoperative incidence of IOP spike was higher in long-AL eyes.

Comparison of Short-term Visual Acuity Changes After Trabeculotomy ab Interno Using Trabectome and Trabeculectomy ab Externo

PURPOSE

To compare short-term visual acuity (VA) changes after trabeculotomy ab interno (TAI) using trabectome and trabeculectomy ab externo (TAE) performed on pseudophakic eyes.

DESIGN

A single-center retrospective study.

PARTICIPANTS

Patients with pseudophakic eyes who had primary open-angle glaucoma or exfoliation glaucoma and underwent TAI or TAE alone.

METHODS

Changes in intraocular pressure (IOP), medication score, Snellen VA, and the number of eyes with vision loss (loss of ≥ 2 Snellen lines) were evaluated at baseline, week 1, and months 1, 3, and 6. The risk factors for vision loss at 6 months postoperatively were analyzed in both groups.

MAIN OUTCOME MEASURES

Visual acuity changes.

RESULTS

A total of 112 eyes of 112 patients were examined: 46 in the TAI group and 66 in the TAE group. Intraocular pressure was significantly lower in both groups at each visit than at baseline. The TAI group had a significantly higher mean postoperative IOP than the TAE group. Medication scores in the TAI group were significantly different after 3 months compared with baseline; however, decreased significantly at all study visits in the TAE group. The mean VA in the TAI group did not decrease significantly at each visit. In the TAE group, it decreased significantly up to 3 months but was not significantly different at 6 months. At all study visits, the number of eyes with vision loss was significantly lower in the TAI group than in the TAE group. Only 2 eyes in the TAI group (4.3%) had vision loss at 6 months, which was caused by macular edema. In the TAE group, 13 eyes (19.7%) experienced vision loss at 6 months. In all cases, the presence of preoperative split fixation [odds ratio = 7.30, P < 0.05] and the occurrence of hypotony-related complications [odds ratio = 6.76, P < 0.05] within 6 months were risk factors for vision loss.

CONCLUSIONS

TAI lowered IOP less than TAE; however, there was less vision loss with TAI. For eyes with a target IOP in the mid-teens, TAI can be recommended as initial surgery.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosuremay be found in the Footnotes and Disclosures at the end of this article.

Favorable effect of ripasudil use on surgical outcomes of microhook ab interno trabeculotomy

PURPOSE

We have previously demonstrated that prolonged use of glaucoma medications was associated with a poor surgical outcome of ab interno trabeculotomy (µTLO). Given that almost all types of glaucoma eye drop either enhance the drainage through the uveoscleral pathway or reduce aqueous humor production, we hypothesized that prolonged use of these medications might cause disuse atrophy of the conventional pathway. In contrast, ripasudil increases the conventional outflow and eventually shows a favorable outcome of µTLO. This study aimed to evaluate the effect of ripasudil use on µTLO outcomes.

METHOD

The medical charts of 218 patients who underwent µTLO were analyzed retrospectively. We compared the 1-year outcome between ripasudil users versus nonusers by using propensity score matching. We set the covariates as age, sex, glaucoma types, preoperative intraocular pressure (IOP), the mean deviation values of visual field tests, the presence or absence of concomitant cataract surgery, trabecular meshwork incision range, the presence or absence of any glaucoma medication except ripasudil and duration of glaucoma medical therapy. Success was defined as a postoperative IOP between 5 and 21 mmHg, a ≥ 20% IOP reduction from baseline, and no additional glaucoma surgery at postoperative 1 year.

RESULT

Fifty-seven patients each were allocated to the ripasudil users or nonusers. The 1-year success rates were 74% in ripasudil users and 51% in nonusers (p = 0.01). Kaplan‒Meier survival curves also showed that the ripasudil users had a higher survival distribution (p = 0.01).

CONCLUSION

The patients who took ripasudil showed a favorable 1-year outcome of µTLO.

Hydrus microstent for the treatment of primary open-angle glaucoma: overview of its safety and efficacy

INTRODUCTION

Minimally invasive glaucoma surgeries (MIGS) are now a consolidated reality in many surgical units. The Hydrus Microstent is one of several MIGS devices bypassing trabecular outflow and had excellent results over the years. This article aims to review the key features of the Hydrus Microstent in terms of design, efficacy, and safety.

AREAS COVERED

The present review analyses the main characteristics of the device by evaluating the technical and physical details of its functioning. The evidence that supports a clinical decision summarizes the most influential clinical trials and the most accurate systematic reviews.

EXPERT OPINION

The Hydrus device has been extensively studied regarding biocompatibility and outflow potential. The subsequent clinical studies have been well-built and proved that the device effectively reduces intraocular pressure (IOP) and the eyedrop load. The device covers almost a quarter of Schlemm's canal circumference, offering at least two advantages: cannulating the Schlemm's canal provides evidence that the device has been implanted correctly; covering a larger area potentially allows to target multiple collector channels or at least areas of active outflow. This scaffold may prove more effective in naïve patients or subjects who used antiglaucoma eyedrops for a limited period, as the prolonged use of hypotonic medications has been associated with the surgical failure of ab interno microhook trabeculotomy.

Application of a Magnetic Platform in α6 Integrin-Positive iPSC-TM Purification

The emergence of induced pluripotent stem cell (iPSC) technology has provided a new approach to regenerating decellularized trabecular meshwork (TM) in glaucoma. We have previously generated iPSC-derived TM (iPSC-TM) using a medium conditioned by TM cells and verified its function in tissue regeneration. Because of the heterogeneity of iPSCs and the isolated TM cells, iPSC-TM cells appear to be heterogeneous, which impedes our understanding of how the decellularized TM may be regenerated. Herein, we developed a protocol based on a magnetic-activated cell sorting (MACS) system or an immunopanning (IP) method for sorting integrin subunit alpha 6 (ITGA6)-positive iPSC-TM, an example of the iPSC-TM subpopulation. We first analyzed the purification efficiency of these two approaches by flow cytometry. In addition, we also determined cell viability by analyzing the morphologies of the purified cells. To conclude, the MACS-based purification could yield a higher ratio of ITGA6-positive iPSC-TM and maintain a relatively higher cell viability than the IP-based method, allowing for the preparation of any iPSC-TM subpopulation of interest and facilitating a better understanding of the regenerative mechanism of iPSC-based therapy.

Mid-Term Results of Ab Interno Trabeculectomy among Japanese Glaucoma Patients

BACKGROUND

The evaluation of ab interno trabeculectomy, referred to as trabectome®, among Japanese patients is insufficient.

SUBJECTS AND METHODS

Japanese patients who underwent trabectome® at the University of Yamanashi Hospital were included. The investigated parameters were intraocular pressure (IOP), best corrected visual acuity, glaucoma medications, visual field, and corneal endothelial cell density. The success rate and its associated factors were investigated.

RESULTS

A total of 250 eyes from 197 patients were enrolled. The trabectome® significantly reduced IOP and glaucoma medications up to 48 months. Concomitant cataract extraction enhanced the reduction in IOP and glaucoma medications up to 42 months. At 36 months postoperatively, 40.8% satisfied IOP of the same or less than 18 mmHg or more than a 20% IOP reduction with the same or less use of glaucoma medications as preoperatively. Preoperative IOP and combined cataract extraction were significantly associated with the success rate. The trabectome® alone did not show a significant reduction in corneal endothelial cells. Eyes with postoperative transient IOP elevation and removal of anterior chamber hemorrhage were 11.2% and 1.2%, respectively. Twenty-four eyes (9.6%) underwent additional glaucoma surgeries.

CONCLUSIONS

The trabectome® could be considered an effective and safe surgery. Compared to trabectome® alone, combined cataract surgery was superior in lowering IOP and reducing glaucoma medications.

The case for standalone micro-invasive glaucoma surgery: rethinking the role of surgery in the glaucoma treatment paradigm

PURPOSE OF REVIEW

To highlight progress in glaucoma therapy challenging the traditional medication-first approach and present evidence supporting early standalone surgery in the era of micro-invasive glaucoma surgery (MIGS).

RECENT FINDINGS

Medical therapy is limited by well documented poor adherence that compromises the quality of intraocular pressure reduction. Results from modern clinical trials demonstrate advantages of selective laser trabeculoplasty and MIGS procedures in terms of both IOP control and progression risk.

SUMMARY

The MIGS options for pseudophakic or precataractous patients are limited by regulatory rules that require the performance of some procedures only at the time of cataract surgery. These include the iStent/iStent Inject and the Hydrus implants. Nonbleb-forming procedures currently available for standalone use in eyes with mild-moderate primary open-angle glaucoma include gonioscopy-assisted transluminal trabeculotomy (which lowers IOP by 28-61% and medication use by 38-73% in various studies), trabecular ablation with the Trabectome (23-39% and 21-43%, respectively), excisional goniotomy with the Kahook Dual Blade (15-36% and 15-40%, respectively), ab interno canaloplasty (35% and 57%, respectively), and combined canaloplasty and trabeculotomy using the OMNI system (39-40% and 64-73%, respectively). For patients who would benefit from early standalone surgery, these procedures offer meaningful reductions in both IOP and medication burden.

Minimally Invasive Glaucoma Surgery: Safety of Individual Devices

Primary open-angle glaucoma progression in those already on maximal medical therapy has traditionally been treated with trabeculectomy, a surgical procedure that carries a high degree of morbidity. In the last few decades, significant advances have been made in the field of minimally invasive glaucoma surgery (MIGS) devices, which aim to defer or prevent trabeculectomy via less arduous surgical techniques in certain types of glaucoma. Although reviews have been published examining the efficacy of various MIGS techniques, no article synthesises the comparative safety of all available devices. We performed a literature review examining the safety of MIGS devices. Fifteen devices were included, variously attempting to increase aqueous outflow through the trabecular meshwork or the suprachoroidal space, shunting into the subconjunctival space, or reducing aqueous production through ciliary body ablation. Notably, the earliest product attempting to increase outflow to the suprachoroidal space, Alcon's CyPass Micro-Stent, was withdrawn from the market due to concerns regarding increased corneal endothelial cell loss at five years post-implantation. All other devices were described as well-tolerated, with the most common adverse effects including hyphaema, intraocular pressure spikes, and device migration or obstruction. MIGS devices are purported to be uniformly safe, and many studies report no statistically significant increased complications beyond those associated with cataract surgery alone. It is important to note, however, the generally poor quality of current studies, with a dearth of randomised, or even prospective, data, and a large proportion of studies funded by device producers.

Stand-Alone Xen Gel Microstent Implantation Compared With Kahook Dual Blade Goniotomy

PRCIS

Both Xen gel Microstent implantation and Kahook Dual Blade (KDB) goniotomy are safe and effective as stand-alone procedures, but the Xen Gel Microstent was associated with more postoperative interventions and achieved higher success at a lower intraocular pressure threshold.

PURPOSE

To evaluate outcomes of stand-alone Xen Gel Microstent implantation compared with stand-alone KDB goniotomy for moderate to severe glaucoma.

METHODS

A retrospective, single-center, case-series analysis comparing outcomes of Xen Gel Microstent implantation and KDB goniotomy stand-alone cases in 75 eyes. Primary outcomes included intraocular pressure (IOP) reduction, glaucoma medication reduction, surgical success, and complications. Surgical success was defined using IOP<21 mm Hg and IOP<18 mm Hg thresholds, with or without glaucoma medications, and without further glaucoma surgery. Subjects were followed for at least 24 months after surgery.

RESULTS

Mean baseline IOP was comparable between the Xen Gel Microstent and KDB goniotomy groups (23.7±8.4 and 25.9±7.9 mm Hg, respectively, P =0.32). At 24 months after surgery, the mean IOP after Xen Gel Microstent was 14.7±3.2 mm Hg (32.7% reduction from baseline, P =0.018) and KDB goniotomy was 16.7±3.2 mm Hg (40.4% reduction from baseline, P =0.049). Although the mean IOP was significantly lower during the first month after Xen Gel Microstent implantation, no difference in mean IOP was observed between the 2 treatment groups at 24 months after surgery ( P =0.416). At 24 months after surgery, the percent reduction of IOP from baseline was not significantly different between the 2 groups. The mean reduction of glaucoma medications from baseline at 24 months was 1.69 drops after Xen Gel Microstent implantation ( P =.008) and 1.67 drops after KDB goniotomy ( P =0.038). Postoperative complications were nonvision-threatening and were not significantly different between the 2 groups ( P =0.550). Interventions not included with complications were needling performed in 21 (37%) of eyes in the Xen Gel Microstent group and Nd:YAG goniopuncture in 1 (5.6%) eye after KDB goniotomy. With an IOP threshold <21 mm Hg, surgical success was not significantly different between the 2 groups ( P =0.06). At a lower IOP threshold (<18 mm Hg), surgical success was higher after Xen Gel Microstent implantation compared with KDB goniotomy ( P =0.001).

CONCLUSIONS

Both stand-alone Xen Gel Microstent implantation and KDB goniotomy can effectively and safely reduce IOP for moderate to severe glaucoma. The Xen Gel Microstent was associated with a higher need for postoperative interventions and achieved greater success at a lower IOP threshold.

iStent Trabecular Micro-bypass Stent Implantation Combined with Phacoemulsification for Open-Angle Glaucoma: A 2-Year Post-marketing Surveillance Study in Japan

Introduction

We report 2-year outcomes after implantation of iStent trabecular micro-bypass stent with phacoemulsification, in Japanese patients with mild–moderate open-angle glaucoma (OAG).

Methods

This was a 24-month, prospective, longitudinal, observational, post-marketing study conducted between July 2017 and September 2020. Patients consisted of adults with OAG on antiglaucoma medications who had cataract surgery combined with one iStent implantation. Outcome measures included intraocular pressure (IOP), antiglaucoma medications, treatment success rates (defined as eyes having lower IOP with same or reduced number of medications from baseline, or same IOP with reduced number of medications from baseline, and not requiring secondary glaucoma surgeries postoperatively), and safety. Outcomes were analyzed in the overall cohort and in glaucoma subtypes: primary OAG, normal-tension glaucoma, and exfoliative glaucoma.

Results

Overall, 232 eyes were enrolled. At 24 months, mean ± standard deviation IOP decreased from 17.6 ± 4.0 mmHg preoperatively to 14.3 ± 3.0 mmHg (p < 0.05), and mean number of medications reduced from 2.2 ± 1.2 preoperatively to 0.7 ± 1.2 (p < 0.05). Similar trends were observed across glaucoma subtypes. In the overall cohort, 96.7%, 95.3%, and 93.7% of patients achieved treatment success at 6, 12, and 24 months, respectively. There were 67.6% medication-free eyes at 24 months compared to 3.2% medication-free eyes preoperatively (p < 0.0001). Safety profile was favorable over the 2-year period.

Conclusions

Following iStent implantation with phacoemulsification, clinically relevant and statistically significant reductions in IOP and number of medications were observed in Japanese eyes with OAG over 2 years, with favorable safety profile. These reductions were observed across all glaucoma subtypes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02207-0.

Trabeculopuncture as a predictive test of distal outflow resistance in canal-based surgery

We investigated whether trabeculopuncture (TP) could detect distal outflow resistance to predict the outcome of canal-based glaucoma surgery such as ab interno trabeculectomy (AIT). These procedures have a high utilization in open angle glaucoma, but fail in eyes with an unidentified distal outflow resistance. We assigned 81 porcine eyes to two groups: trial (n = 42) and control (n = 39). At 24 h, four YAG-laser trabeculopunctures were placed nasally, followed by a 180° AIT at the same site at 48 h. The proportion of TP responders between both AIT groups was compared. Histology and outflow canalograms were determined. Both post-TP and post-AIT IOPs were lower than baseline IOP (p = 0.015 and p < 0.01, respectively). The success rates of TP and AIT were 69% and 85.7%, respectively. Sensitivity and specificity values of TP as predictive test for AIT success were 77.7% and 83.3%, respectively. The positive and negative predictive values were 96.6% and 38.5%, respectively. We conclude that a 10% reduction in IOP after TP can be used as a predictor for the success (> 20% IOP decrease) of 180° AIT in porcine eyes.

Outcomes of Prolene Gonioscopy-assisted Transluminal Trabeculotomy in Primary Open-angle Glaucoma and Pseudoexfoliative Glaucoma: A Comparative Study

PRCIS

Gonioscopy-assisted transluminal trabeculotomy (GATT) provides greater intraocular pressure (IOP) reduction in pseudoexfoliative glaucoma (PXG) than in primary open-angle glaucoma (POAG) in the first years of surgery; however, the difference between groups equalizes in the long-term.

PURPOSE

To compare outcomes of GATT in eyes with POAG and PXG.

METHODS

Single-center, retrospective, comparative case series. A total of 202 eyes (91 eyes of POAG; 111 eyes of PXG) were included. GATT was performed as a standalone procedure or in combination with cataract extraction (CE). Outcome measures were change in IOP and number of medications at all time points (1, 3, 6, 9, 12, 18, 24, and 36 mo after surgery), success rate (IOP reduction ≥20% from baseline or IOP between 6-21 mmHg, without further glaucoma surgery), and complication rate. Cumulative success probabilities were compared using Kaplan-Meier survival analyses.

RESULTS

The mean IOP decreased by 8.8 mmHg (34.4%) in the POAG group with a mean decrease of 2 glaucoma medications at final visit. In the PXG group, the mean IOP decreased by 12.8 mm Hg (44.6%) on 2.3 fewer medications. Mean IOP reduction was significantly higher in PXG than POAG at all time points up to 2-year visit (P<0.05 for all), after which the difference was not significant. Cumulative success probability during the first year was significantly higher in PXG (97.6%) than in POAG (86.8%) (P=0.01); no significant difference was found at 2-year (P=0.07) and 3-year visits (P=0.24).

CONCLUSION

GATT was safe and effectively reduced the IOP and medication burden in patients with POAG and PXG. In the first year following GATT, a significantly higher success rate was noted in PXG compared to POAG, however, in subsequent years, the success rate was similar at ~ 75%.

Risk of surgical failure and hemorrhagic complications associated with antithrombotic medication in glaucoma surgery

PURPOSE

The purpose of this retrospective study was to determine the extent to which the use of antithrombotic drugs during glaucoma surgery contributes to surgical failure and postsurgical hemorrhagic complications.

METHODS

Glaucoma surgeries were categorized into three groups: trabeculotomy (TLO), trabeculectomy (TLE), and long-Tube shunt surgery (Tube). At 1 year after surgery, the following criteria for surgical success were met: intraocular pressure (IOP) in the 5-21-mmHg range, IOP reduction of at least 20% from the preoperative level, and no additional glaucoma surgeries. We compared the percentages of the success rates and hemorrhagic complications between antithrombotic medication experiencers and non-experiencers. Furthermore, we adjusted the preoperative factors between the two groups using a propensity score analysis in TLO and TLE surgeries.

RESULTS

A total of 910 glaucoma surgeries were included, with TLO, TLE, and Tube accounting for 353, 444, and 113 surgeries, respectively. Preoperative antithrombotic medications were administered to 149 patients in all glaucoma surgeries: 37 patients used only anticoagulants, 102 used only antiplatelets, and 10 used both. There was no significant difference in the success rates of any of the procedures. The hemorrhagic complications (hyphema and vitreous hemorrhage rate) were significantly higher in the patients who underwent TLE and Tube. The surgical success rates of TLO and TLE were not significantly different after the two groups were matched by propensity score.

CONCLUSION

The perioperative use of antithrombotic drugs did not affect success for any of the procedures. However, it increased early postoperative hemorrhagic complications for TLE and Tube.

Six-month outcomes of combined conventional needle goniotomy and phacoemulsification in eyes with early to moderate primary open-angle and pseudoexfoliation glaucoma and ocular hypertension

Purpose:

Angle-based surgeries for the treatment of open-angle glaucoma have gained popularity in recent years. This study aimed to evaluate the efficacy of combined phacoemulsification and goniotomy in primary open-angle and pseudoexfoliation glaucoma (POAG and PXG) and ocular hypertension (OHTN).

Methods:

In this interventional case series in the setting of the Glaucoma Service at the Farabi Eye Hospital, 32 eyes of 30 patients with early-to-moderate POAG and PXG and OHTN were enrolled. All eyes underwent combined phacoemulsification and needle goniotomy. Intraocular pressure (IOP) and the number of antiglaucoma medications as well as demographic data were recorded at baseline and one day, one week, one month, three months, and six months after the surgery. Generalized Estimating Equation (GEE) was used to compare the values of IOP and the number of medications at different time points. Kaplan–Meier graph was used to demonstrate the survival status of the eyes.

Results:

Mean IOP at baseline was 21.8 ± 4.6 mmHg on mean 1.2 ± 1.5 topical medications. There was a 25.2% (16.3 ± 4.5 mmHg) and 32.1% (14.8 ± 3.9 mmHg) reduction in IOP at three and six months after procedure, respectively (P < 0.001). Meanwhile, the decline in medications was 66.7% (0.4 ± 0.9) and 50.0% (0.6 ± 1.1) at the same time points (P = 0.002 and P = 0.048, respectively). Post-operative complications were clot hyphema (n = 1, 3.1%), fibrinous inflammation (n = 1, 3.1%) and distorted pupil (n = 2, 6.3%).

Conclusion:

Combined phacoemulsification and needle goniotomy as a procedure for mild and moderate POAG and PXG and OHTN is as effective as other modified goniotomies in the setting of minimally invasive glaucoma surgeries (MIGS).

A Prospective Study of Intraocular Pressure Spike and Failure After Gonioscopy-Assisted Transluminal Trabeculotomy in Juvenile Open-Angle Glaucoma: A Prospective Study of GATT in JOAG

PURPOSE

To identify risk factors for surgical failure after gonioscopy-assisted transluminal trabeculotomy (GATT) in juvenile open-angle glaucoma (JOAG).

DESIGN

Prospective, interventional case series.

METHODS

GATT was the initial surgery in 70 eyes of 70 patients with JOAG. Surgical success was defined as a postoperative intraocular pressure (IOP) of ≤21 mm Hg with at least a 20% reduction from preoperative IOP, with or without the use of antiglaucoma medication (qualified and complete success, respectively) at each postoperative visit. IOP spike was defined as IOP >30 mm Hg and an increase of at least 10 mm Hg from IOP before the spike, and then reduced to ≤21 mm Hg.

RESULTS

The median age at the time of surgery was 19.3 years (range, 4.9-37.5 years) with a visual field mean deviation of -17.4 ± 10.6 dB. Mean IOP decreased from 31.3 ± 9.5 mm Hg preoperatively to 15.8 ± 2.7 at 12 months postoperatively. The complete and qualified success rates were 74.3% and 91.4%, respectively. An IOP spike occurred in 52 eyes (74%), with a median spike duration of 3.5 days (range, 1-21 days). Longer duration of IOP spike (P = .009) and older age at the time of surgery (P = .025) were both associated with worse surgical outcomes. Advanced disease was associated with prolonged IOP spike (P = .007).

CONCLUSIONS

GATT provided excellent outcomes in patients with severe JOAG. Older age and longer duration of postoperative IOP spike are risk factors for failure. Severe cases are more likely to have longer durations of IOP spike. Frequent IOP monitoring during the early postoperative period is needed to detect IOP spikes in these patients.

Association of the prolonged use of anti-glaucoma medications with the surgical failure of ab interno microhook trabeculotomy

PURPOSE

This study examined the perioperative factors affecting surgical success in ab interno microhook trabeculotomy (μTLO).

METHODS

A total of 146 consecutive patients who underwent μTLO were included in this retrospective study. We performed Cox proportional hazard modelling by setting surgical success at 1 year as an objective variable. The explanatory variables included age, sex, glaucoma type, preoperative intraocular pressure (IOP), glaucoma drug score, mean deviation (MD) of the Humphrey visual field test, duration of glaucoma drug use, antithrombotic drug use, combined cataract surgery, incision range and diabetes mellitus. Additionally, we performed 1:1 matching using propensity score analysis and compared the perioperative parameters between durations of glaucoma drug use of <4.5 years and ≥ 4.5 years (50 patients each). We defined surgical success as satisfaction of all three criteria: IOP 5-21 mmHg, IOP reduction of ≥20% from the preoperative IOP and no additional glaucoma surgery.

RESULTS

The Cox proportional hazard model revealed that a longer duration of anti-glaucoma medication was significantly associated with surgical failure. Propensity score matching analysis showed that the <4.5-year users of anti-glaucoma drugs had significantly higher success rates than the ≥4.5-year users (72% versus 52%; p = 0.04).

CONCLUSIONS

The prolonged use of multiple glaucoma drugs adversely affected the outcome of μTLO at least at 1 year postoperatively.

Non-inferiority of Microhook to Trabectome: Trabectome vs. ab interno Microhook Trabeculotomy Comparative Study (TramTrac Study)

PURPOSE

To elucidate the non-inferiority of ab interno microhook trabeculotomy (μTLO) using a recently developed reusable stainless spatula-type microhook device to incise the trabecular meshwork to trabectome (TOM) in terms of the 1-year postoperative outcomes of Japanese patients with glaucoma by means of propensity score analyses.

DESIGN

A multicenter retrospective cohort study.

PARTICIPANTS

We enrolled 553 and 392 patients who underwent TOM and μTLO, respectively, between January 2014 and March 2020 at 10 facilities.

METHODS

Logistic regression analysis was conducted to calculate the propensity score, which indicates the likelihood of treatment assignment (TOM or μTLO). We set the following factors as outcome-related covariates: age, sex, facility, glaucoma disease types, preoperative intraocular pressure (IOP), glaucoma drug score, mean deviation of the Humphrey visual field test and antithrombotic drug use, the presence or absence of combined cataract surgery, and incision range of trabecular meshwork (one or two quadrants). We analyzed four different methods (matching, inverse probability of treatment weighting (IPTW), stratification, and regression adjustment) using the propensity score. We set 15% as the non-inferiority margin based on previous trabectome meta-analysis results.

MAIN OUTCOME MEASURES

The primary outcome was surgical success at 1 year postoperatively. We defined surgical success as satisfying all three criteria: (1) IOP within 5-21 mmHg; (2) IOP reduction of ≥20% from preoperative IOP; and (3) no additional glaucoma surgery.

RESULTS

The 95% confidence interval of risk difference of surgical failure in μTLO in reference to TOM was -12.1 to +9.5% in matching, -12.7 to +11.1% in IPTW, -12.2 to +7.0 in stratification, and -9.7 to +8.1% in regression adjustment, all of which fell within the predetermined non-inferiority margin of 15%.

CONCLUSIONS

Surgical success of μTLO at 1-year postoperatively was not inferior to that of TOM.

Minimally Invasive Glaucoma Surgery-to Remove or Preserve the Trabecular Meshwork: That is the Question?

How to cite this article: Dada T, Mahalingam K, Bhartiya S. Minimally Invasive Glaucoma Surgery—to Remove or Preserve the Trabecular Meshwork: That is the Question? J Curr Glaucoma Pract 2021;15(2):47–51.

Prediction of trabecular meshwork-targeted micro-invasive glaucoma surgery outcomes using anterior segment OCT angiography

We performed a prospective, longitudinal study to investigate the association between the preoperative intrascleral vasculature assessed using anterior segment (AS)-optical coherence tomography angiography (OCTA) and surgical outcomes of trabecular meshwork-targeted micro- or minimally invasive glaucoma surgery (MIGS). We included 37 patients with primary open-angle glaucoma. Preoperative AS-OCTA images of the sclero-conjunctiva of the nasal corneal limbus were acquired in the superficial (conjunctival) and deep (intrascleral) layers. The vessel densities (VDs) of each layer were measured separately in the entire area, limbal side, and fornix area. Surgical success was determined by postoperative intraocular pressure (IOP) and IOP reduction. Twenty-three and 14 eyes were classified as having successful and unsuccessful outcomes, respectively. The deep VDs of the entire area and fornix area were significantly lower in the successful group (P = 0.031 and P = 0.009). The success rate was significantly higher for eyes with a lower deep VD than for eyes with a higher deep VD. A greater IOP reduction was significantly associated with lower deep VD in the fornix area (P = 0.022) and higher preoperative IOP (P < 0.001). These results indicate that intrascleral vasculature assessed using preoperative AS-OCTA was negatively correlated with surgical success and IOP reduction resulting from trabecular meshwork-targeted MIGS. AS-OCTA images might help predict MIGS outcomes.

Characteristics of glaucoma patients with intraocular pressure elevation early after trabectome surgery

PURPOSE

To analyze the rate and time of occurrence of intraocular pressure (IOP) elevation early after trabectome surgery (TOM) and the characteristics of glaucoma patients recovering from IOP elevation.

METHOD

Four hundred sixty eyes of 460 glaucoma (191 primary and 269 secondary open-angle glaucoma) patients who underwent TOM were evaluated. IOP elevation early after TOM was diagnosed when IOP increased by more than 5 mmHg over baseline within 1 week to 3 months. If the IOP decreased with the administration of anti-glaucoma eye drops alone, patients were classified as recovered. If the IOP did not decrease despite additional anti-glaucoma eye drop use, patients were classified as non-recovered. The rate and time of occurrence of IOP elevation early after TOM were investigated. Demographic and ocular variables related to recovery and non-recovery were identified by multivariate logistic regression analysis.

RESULTS

Of the 460 patients, IOP elevation early after TOM occurred in 102 (22.2%). IOP elevation occurred most frequently at postoperative week 1. Of the 102 patients with IOP elevation, 55 (53.9%) recovered and 47 (46.1%) did not. A large hyphema size the day after surgery was associated with increased likelihood of recovery from IOP elevation (odds ratio [OR], 6.6). A history of past selective laser trabeculoplasty (SLT; OR, 0.10) and high baseline IOP (OR, 0.86) were associated with reduced likelihood of recovery from IOP elevation.

CONCLUSION

IOP elevation early after TOM occurred most frequently at postoperative week 1. Patients with a large hyphema size, no history of SLT, and a lower baseline IOP recovered from IOP elevation early after TOM. A large hyphema the day after surgery suggested an increased likelihood of recovery from IOP elevation.

Comparison of Surgical Outcomes Between Ab Interno Suture Trabeculotomy and Ab Externo Metal Trabeculotomy in Adult Patients with Glaucoma

Purpose

To compare the outcomes of ab interno suture trabeculotomy (AbI-TLO) and ab externo metal trabeculotomy (AbE-TLO) in adult patients with glaucoma aged over 40 years.

Patients and Methods

A retrospective chart review was conducted, including adult patients with glaucoma who underwent AbI-TLO or AbE-TLO between January 2015 and June 2019. A single surgeon (YO) performed all the operations. Eighty-one patients (81 eyes) were included in this study. Surgical success was defined as a postoperative intraocular pressure (IOP) of ≤18 mmHg and an IOP reduction of ≥20% from the preoperative IOP, without requiring additional glaucoma surgery. Success rates were assessed using Kaplan-Meier survival curves and log-rank (Mantel-Cox) tests, while risk factors were analyzed using the Cox proportional hazards model.

Results

Forty-nine patients who underwent AbI-TLO and 32 patients who underwent AbE-TLO were studied; the preoperative IOPs were 27.9 ± 7.3 (mean ± standard deviation) mmHg and 25.6 ± 8.1 mmHg in the AbI-TLO and AbE-TLO groups, respectively (p=0.217). The 12-month postoperative IOPs were 15.8 ± 4.0 mmHg and 16.3 ± 4.2 mmHg in the AbI-TLO and AbE-TLO groups, respectively (p=0.724). The surgical success rates at 12 months were 77.6% and 62.5% in the AbI-TLO and AbE-TLO groups, respectively (p=0.144). Postoperative hyphema with level formation and ocular hypertension over 30 mmHg were observed in 22.4% and 26.5% of patients in the AbI-TLO group and 18.8% and 12.5% of those in the AbE-TLO group, respectively. Stepwise multivariate Cox regression analysis showed that a longer axial length was a risk factor for surgical failure (hazard ratio: 2.030; p=0.042).

Conclusion

AbI-TLO and AbE-TLO had similar surgical outcomes and postoperative complications. A longer axial length was associated with an insufficient IOP reduction.

Reoperation for complications within 90 days of minimally invasive glaucoma surgery

OBJECTIVE

To describe reoperations that occurred within 90 days of minimally invasive glaucoma surgery (MIGS) at a single institution over a 30-month period.

SETTING

Tertiary care hospital.

DESIGN

Retrospective case series.

METHODS

Charts of adult patients who underwent trabecular microbypass stents, gel microstents, and goniotomy procedures (including gonioscopy-assisted transluminal trabeculotomy) from October 1, 2017, to March 15, 2020, at Wills Eye Hospital were examined. Outcome measures were unanticipated reoperations within the first 90 days after MIGS procedures and the complications that led to these reoperations.

RESULTS

A total of 448 MIGS procedures were performed on 436 eyes of 348 patients over a 30-month period by 6 glaucoma surgeons. Of these, 206 (46.0%) were trabecular microbypass stents (198 iStent/iStent inject and 8 Hydrus), 152 (33.9%) were gel microstents, and 90 (20.1%) were goniotomy procedures. Combined phacoemulsification took place in 256 eyes (58.7%). Reoperation within 90 days took place in 23 (5.3%) of 436 eyes, including 16 (10.5%) of 152 eyes in the gel microstent group, 4 (2.0%) of 198 eyes in iStent/iStent inject group, and 3 (3.3%) of 90 eyes in the goniotomy group. Indications for reoperation were elevated intraocular pressure (IOP) in 16 (69.6%) of 23 eyes, gel microstent tip exposure with wound leakage in 3 (13.0%) of 23 eyes, and early gel microstent encapsulation without elevated IOP in 1 (4.3%) of 23 eyes. Two (8.7%) of 23 eyes required reoperation for intraocular lens complications, whereas 1 (4.3%) of 23 eyes had elevated IOP and aphakia requiring reoperation.

CONCLUSIONS

The rate of reoperation within the first 90 days after MIGS was low. Elevated IOP and complications associated with gel microstents were the main indications for reoperation.

Factors associated with achieving intraocular pressure lower than 15 mmHg by Trabectome surgery in primary open-angle glaucoma

To assess good prognostic factors of Trabectome surgery in primary open-angle glaucoma (POAG), clinical records of patients with POAG who underwent Trabectome surgery with/without cataract surgery as the first additive therapy to eye drops between January 2015 and March 2018 were retrospectively reviewed. Overall, data of 79 eyes (79 patients; 50 men; mean age, 68.0 years) up to postoperative 24 months were analyzed. Their mean intraocular pressure (IOP) was 20.4 ± 6.0 mmHg at baseline. Forty-two eyes (53.2%) achieved an IOP < 15 mmHg and ≥ 20% reduction from baseline without additional treatments. Phakic eyes had a better survival probability than pseudophakic eyes after adjusting for age, sex, baseline IOP, best-corrected visual acuity, and eye drop score (hazard ratio 3.096; 95% confidence interval [95% CI] 1.367–7.013; P = 0.007). Phakic eyes treated with combined Trabectome and cataract surgeries (mean survival time, 22.250 months; 95% CI 17.606–26.894) had a better survival probability than pseudophakic eyes treated with Trabectome surgery only (mean survival time, 12.111 months; 95% CI 8.716–15.506; P = 0.009) after the adjustment. Among the eyes treated with Trabectome surgery only, phakic eyes required significantly less additional treatments than pseudophakic eyes (P = 0.04). Trabectome surgery may be indicated for phakic eyes with POAG in addition to eye-drop therapy.

Ethics of Glaucoma Widgets

How to cite this article: Dada T, Ramesh P, Sethi A, et al. Ethics of Glaucoma Widgets. J Curr Glaucoma Pract 2020;14(3):77–80.

The Outcomes of Trabectome Surgery in Patients with Low, Middle, and High Preoperative Intraocular Pressure

Background

We compared the efficiency of trabectome surgery for patients with differing preoperative intraocular pressure (IOP) values in a single-facility retrospective study. We evaluated surgical outcomes based on three grades of preoperative IOP: high (hi-IOP, >26 mmHg), middle (mid-IOP, 18–26 mmHg), and low (lo-IOP, <18 mmHg).

Patients and Methods

We analyzed the cases of 204 eyes that underwent trabectome surgery and were followed >2 years. We defined failure as a reduction of IOP <20% or requiring additional glaucoma surgery. We used 4 cutoff values >21, >18, >15, and >12 mmHg. Other factors that may affect surgical outcomes were also investigated: age, central corneal thickness (CCT), history of selective laser trabeculotrabculoplasty (SLT), preoperative visual field, and simultaneous cataract surgery.

Results

Trabectome surgeries significantly decreased the IOP values from 23.0 ± 7.2 mmHg to 13.6 ± 3.6 mmHg at 2 years post-surgery. The mid-IOP group achieved significantly better surgical outcomes than the lo-IOP and hi-IOP groups with cutoff values 21, 18, and 15 mmHg. A thin CCT and simultaneous cataract surgery were significantly related to better surgical outcomes with cutoff value 21.18 and 15 mmHg.

Conclusion

For the patients with preoperative IOP <18 mmHg, it was difficult to decrease their IOP >20% with trabectome surgery. Patients with preoperative IOP values >26 mmHg often required additional glaucoma surgery.

Effectiveness and limitations of minimally invasive glaucoma surgery targeting Schlemm's canal

Glaucoma surgery is performed to lower intraocular pressure (IOP); ideally, the IOP reduction is safely maintained for an extended period of time. Although trabeculectomy was considered the gold standard for glaucoma surgery for many years because of its effective IOP reduction, yet now it is considered unsafe because of serious complications. In recent years, minimally invasive glaucoma surgery (MIGS), which emphasizes safety and can be performed rapidly, has become widespread. Because MIGS does not involve conjunctival incisions, patients can undergo future trabeculectomy. If IOP reduction can be maintained safely, the number of anti-glaucoma drops can be reduced and visual function maintained, good outcomes for patients with glaucoma. Currently, many types of MIGS approved in Japan are reported to yield relatively good results, with targets of approximately 15-19 mmHg. However, the IOP-lowering effects of MIGS are limited. In procedures targeting Schlemm's canal, it is difficult to lower IOP beyond episcleral venous pressure. In some instances, a beneficial effect cannot be achieved if function is reduced beyond the collector channel. There are many unclear aspects regarding long-term outcomes following MIGS. Notably, investigation is ongoing to determine which patients are likely to benefit most from surgery. Based on previous reports, this review describes the characteristics and results of MIGS, approved in Japan, as well as underlying factors that affect the preoperative predictions and outcomes of the surgical procedure.

Long-term clinical results of trabectome surgery in patients with open-angle glaucoma

PURPOSE

To evaluate the 72-month clinical results of trabectome surgery (TOM) in patients with primary open-angle glaucoma (POAG), secondary OAG and childhood glaucoma.

METHOD

A total of 305 eyes from 249 glaucoma patients were analyzed in the current retrospective single-center study. Kaplan-Meier analysis was performed using three criteria: criterion A (postoperative intraocular pressure [IOP] ≤ 21 mmHg and ≥ 20% reduction from baseline IOP); criterion B (postoperative IOP ≤ 18 mmHg and ≥ 20% reduction from baseline IOP); and criterion C (postoperative IOP ≤ 16 mmHg and ≥ 20% reduction from baseline IOP). The changes in IOP, medication score, success probability, results of the multivariate analysis for success and failure risk factors, and complications were analyzed.

RESULTS

The baseline IOP in all glaucoma patients decreased from 29.2 ± 9.8 mmHg with a 5.3 ± 1.7 medication score to 16.4 ± 5.8 mmHg (- 43.8%) with a 4.2 ± 1.5 medication score at 72 months (p < 0.01). The success probabilities in all cases for 72 months based on criterion A, B, and C were 44%, 35%, and 17%, respectively. For criterion A, no significant differences were found in the success probability according to the glaucoma subtype for 72 months. The combined surgical procedure significantly decreased the failure risk (hazard ratio [HR]: 0.59). On the other hand, the presence of POAG (HR: 1.6) and a history of past selective laser trabeculoplasty (HR: 2.2) significantly increased failure risk. One patient (0.3%) demonstrated endophthalmitis after TOM but recovered through appropriate treatment.

CONCLUSION

At the 72-month time point, approximately half of the glaucoma patients maintained an IOP ≤ 21 mmHg with ≥ 20% IOP reduction. TOM is a safe surgery but may not yield sufficient IOP reduction in patients who have received SLT or have POAG.

Visual outcomes of combined cataract surgery and minimally invasive glaucoma surgery

Minimally invasive glaucoma surgery (MIGS) has become a reliable standard of care for the treatment of glaucoma when combined with cataract surgery. This review describes the MIGS procedures currently combined with and without cataract surgery with a focus on visual outcomes based on the literature and the experience of the ASCRS Glaucoma Clinical Committee.

Twelve-Month Outcomes of Stand-Alone Excisional Goniotomy in Mild to Severe Glaucoma

PURPOSE

To describe 12-month intraocular pressure (IOP) and medication use outcomes following excisional goniotomy (EG) as a stand-alone procedure in eyes with medically uncontrolled glaucoma.

METHODS

This was a retrospective analysis of data from surgeons at 8 centers (6 US, 2 Mexico). Eyes with glaucoma undergoing standalone EG with a specialized instrument (Kahook Dual Blade, New World Medical, Rancho Cucamonga, CA) for IOP reduction and followed for 12 months postoperatively were included. Data were collected preoperatively, intraoperatively, and 1 day, 1 week, and 1, 3, 6, and 12 months postoperatively. The primary outcome was reduction from baseline in IOP, and key secondary outcomes included IOP-lowering medication reduction as well as adverse events.

RESULTS

A total of 42 eyes were analyzed, of which 36 (85.7%) had mild to severe primary open-angle glaucoma (POAG). Mean (standard error) IOP at baseline was 21.6 (0.8) mmHg, and mean number of medications used at baseline was 2.6 (0.2). At 3, 6, and 12 months postoperatively, mean IOP reductions from baseline were 4.6 mmHg (22.3%), 5.6 mmHg (27.7%), and 3.9 mmHg (19.3%) (p≤0.001 at each time point). At the same time points, mean medications reductions of 0.7 (25.8%), 0.9 (32.6%), and 0.3 (12.5%) medications were seen (p<0.05 at months 3 and 6, not significant at month 12). Six eyes (14.3%) underwent additional glaucoma surgery during the 12-month follow-up period.

DISCUSSION

Standalone EG with KDB can reduce IOP, and in many cases reduce medication use, through up to 12 months in eyes with mild to severe glaucoma. Statistically significant and clinically relevant reductions in IOP were seen at every time point. While the goal of surgery was not to reduce medication burden, mean medication use was significantly reduced at all but the last time point. In the majority of eyes, the need for a bleb-based glaucoma procedure was delayed or prevented for at least 12 months.

A comparison of the 1-year surgical outcomes of ab externo trabeculotomy and microhook ab interno trabeculotomy using propensity score analysis

Objective

To compare the 1-year outcomes of trabeculotomy ab externo (ab externo TLO) and trabeculotomy ab interno using a microhook (ab interno TLO) for glaucoma patients using propensity score analysis.

Methods and analysis

The medical charts of 65 consecutive patients who underwent ab externo TLO and those of 69 patients who underwent ab interno TLO were reviewed. Logistic regression analysis was conducted to calculate the propensity score using 1:1 matched analysis, which indicates the likelihood of surgical success at 12 months. We set the outcome-related covariates as age, glaucoma type, mean deviation, preoperative intraocular pressure (IOP), the number of preoperative glaucoma eye drops and the presence or absence of combined cataract surgery. Fifty eyes per each surgery group were subsequently compared.

Results

The mean preoperative IOP was 32.5±11.2 mm Hg in the ab externo TLO group and 28.4±7.8 mm Hg in the ab interno TLO group (p=0.08). The mean postoperative IOP at 12 months was 18.3±7.4 mm Hg in the former group and 17.8±6.3 mm Hg in the latter (p=0.91). When surgical success was defined as a postoperative IOP of between 5 and 21 mm Hg with a more than 20% IOP reduction from baseline and no additional glaucoma surgery, the rate at 12 months was 78% in the ab externo TLO group and 74% in the ab interno TLO group (p=1.00).

Conclusion

The 1-year success rate was not significantly different between ab externo and ab interno TLO.

The Influence of Trabectome Surgery on Corneal Endothelial Cells

PURPOSE

The purpose of this study was to evaluate the influence of trabectome surgery on corneal endothelial cells by site.

METHODS

Retrospective observational study. Trabectome surgeries were performed on 159 eyes of 132 adult Japanese patients. Corneal endothelial cells were measured at the center (C), inferior (I), nasal inferior (NI), nasal superior (NS), superior (S), temporal superior (TS), and temporal inferior (TI) sectors at <1 month preoperatively and 3, 6, 12, 24, and 36 months postoperatively, for changes in corneal endothelial cell density (ECD), coefficient of variation (CV), and incidence of hexagonal cells (6A).

RESULTS

Mean preoperative ECD in all groups were 2401±451 (SD)  cells/mm (C), 2366±450 cells/mm (I), 2397±479 cells/mm (NI), 2476±554 cells/mm (NS), 2493±596 cells/mm (S), 2464±558 cells/mm (TS), and 2329±510 cells/mm (TI). The 12-month postoperative mean ECDs were 2344±480 cells/mm (C), 2312±469 cells/mm (I), 2325±536 cells/mm (NI), 2473±517 cells/mm (NS), 2438±607 cells/mm (S), 2227±578 cells/mm (TS), and 2193±523 cells/mm (TI). There was no change in ECD in all sectors before and after surgery. ECD decreased at the TS and TI in combination with cataract surgery (2620±430 and 2445±384 cells/mm) preoperatively to 2264±501 and 2216±477 cells/mm at 12 months postoperatively. CV and 6A did not change at all sites in all surgical procedures before and after surgery.

CONCLUSIONS

Trabectome surgery involves minimal effects to corneal endothelial cells, although long-term prospective studies with greater sample sizes are necessary to confirm this conclusion.

Can a contact lens sensor predict the success of trabectome surgery?

PURPOSE

We examined whether a contact lens sensor (CLS) is useful for the postoperative evaluation of trabectome surgery. We investigated the correlations between the outcomes of trabectome surgery and the output of a CLS.

METHODS

We examined 24 consecutive eyes of patients with pseudo-exfoliation glaucoma. In each eye, the intraocular pressure (IOP) fluctuations over 24 h were measured with the SENSIMED Triggerfish CLS before and at 3 months after the trabectome surgery. We divided the patients into success (n = 12 eyes) and failure (n = 12 eyes) groups; success was defined as a postoperative IOP level ≤ 21 mmHg plus an IOP reduction ≥ 20% relative to the preoperative IOP value with or without anti-glaucoma medications. We investigated CLS parameters that correlate with surgical outcomes by performing a Cox hazard regression analysis. We determined the maximum value, minimum value, and range of IOP fluctuation as CLS parameters.

RESULTS

The mean follow-up period was 38.0 ± 3.0 months. The success rate was 50%. The postoperative range of IOP fluctuation during the nocturnal period with the CLS was significantly correlated with the surgical results (p = 0.024).

CONCLUSIONS

A smaller range of IOP fluctuation was significantly correlated with better surgical outcomes. We were able to predict the surgical success after trabectome surgery at 3 months using the CLS. Thus, CLS results could be a new surgical evaluation parameter.

Early Results of Goniotomy with the Kahook Dual Blade, a Novel Device for the Treatment of Glaucoma

PURPOSE

To report the outcomes of patients who underwent goniotomy with the Kahook Dual Blade (KDB) either as a standalone procedure or in combination with cataract extraction.

PATIENTS AND METHODS

This retrospective chart review included 111 eyes of 90 patients who underwent KDB goniotomy from January to November 2016 at Glaucoma Associates of Texas. KDB goniotomy was combined with cataract surgery in 100 eyes. The main outcome measures were postoperative intraocular pressure (IOP) and number of IOP lowering medications.

RESULTS

Preoperatively, mean IOP was 17.1 ± 4.7 mmHg (range 8-34 mmHg) and mean number of IOP lowering medications was 2.4 ± 1.3 (range 0-6). Postoperatively, mean IOP was 14.9 mmHg, 13.9 mmHg, 14.1 mmHg, 14.4 mmHg, and 14.7 mmHg at 1, 3, 6, 9, and 12 months follow-up, respectively (all p <0.004). Mean numbers of IOP lowering medications were 0.8, 1.0, 1.0, 1.0, and 1.6 at 1, 3, 6, 9, and 12 months follow-up, respectively (all p <0.001). The cumulative reoperation rates for uncontrolled IOP after KDB were 0%, 1.0%, 2.1%, and 4.6% at 3, 6, 9, and 12 months, respectively. Eyes with a preoperative IOP >21 mmHg were significantly more likely to undergo reoperation (p = 0.038, log-rank test). There were no serious complications at any time point in the follow-up period.

CONCLUSION

The Kahook Dual Blade results in a reduction in IOP and use of glaucoma medications after one year of follow-up. Further prospective studies are needed to fully characterize safety and efficacy.

Hydrus microstent implantation for surgical management of glaucoma: a review of design, efficacy and safety

With the advent of microinvasive glaucoma surgery (MIGS), the spectrum of modalities available to manage patients with this chronic and heterogeneous condition has broadened. Despite its novelty however, there has been a rapid evolution in the development of a multitude of devices, each targeting a structure along the aqueous drainage pathway. A growing body of evidence has demonstrated IOP and medication burden reduction, and a more favorable safety profile with MIGS procedures in contrast to traditional incisional surgeries. Among the array of MIGS, the Hydrus® Microstent (Ivantis, Inc., Irvine, CA) is a recent FDA approved device, designed to bypass the trabecular meshwork and provide a scaffold for Schlemm’s canal. The objective of this article is to review the Hydrus from conception to clinical use, and present data on its efficacy and safety to date. The available literature has shown promise, however inherent to all novel devices, only long-term monitoring will ensure sustained IOP control and an acceptable safety profile. Surgical advancements in glaucoma have revolutionized the field, and continued research and development will establish these approaches in clinical treatment algorithms.

Similar Performance of Trabectome and Ahmed Glaucoma Devices in a Propensity Score-matched Comparison

PURPOSE

To apply propensity score matching to Ahmed glaucoma drainage implants (AGI) to trabectome-mediated ab interno trabeculectomy (AIT). Recent data suggest that AIT can produce results similar to AGI traditionally reserved for more severe glaucoma.

METHODS

AGI and AIT patients with at least 1 year of follow-up were included. The primary outcome measures were intraocular pressure (IOP), glaucoma medications, and a Glaucoma Index (GI) score. GI reflected glaucoma severity based on visual field, the number of preoperative medications, and preoperative IOP. Score matching used a genetic algorithm consisting of age, sex, type of glaucoma, concurrent phacoemulsification, baseline number of medications, and baseline IOP. Patients without a close match were excluded.

RESULTS

Of 152 patients, 34 AIT patients were matched to 32 AGI patients. Baseline characteristics including ethnicity, IOP, the number of medications, glaucoma type, the degree of visual field loss and GI were not significantly different between AIT and AGI. AIT had a preoperative IOP of 23.6±8.1 mm Hg compared with 26.5+10.6 mm Hg for AGI. At 12 months, the mean IOP was 15.0±9 mm Hg for AIT versus 15.0±4 mm Hg for AGI (P=0.8), whereas the number of drops was 2.3±2.2 for AIT versus 3.6±1.3 for AGI (P=0.016). Only 6 AIT patients (17.6%) required further surgery within the first 12 months versus 9 (28%) for AGI. Success, defined as IOP<21 mm Hg, <20% reduction and no reoperation, was achieved in 76% of AIT versus 69% of AGI (P=0.48). Complications occurred in 13% of AGI and 0.8% of AIT.

CONCLUSIONS

A propensity score-matched comparison of AIT and AGI showed an equivalent IOP reduction through 1 year. Surprisingly, the AGI group required more glaucoma medications than the AIT group at 6 and 12 months.

Transient ciliochoroidal detachment after 360-degree suture trabeculotomy ab interno for open-angle glaucoma: 12-month follow-up

Objectives

To investigate the effects of ciliochoroidal detachment (CCD) after 360-degree suture trabeculotomy ab interno (360S-LOT ab interno) on intraocular pressure (IOP) and postoperative complications during a 12-month follow-up.

Methods

We prospectively examined 44 eyes of 44 patients for 12 months after 360S-LOT ab interno surgery. Inclusion criteria were open-angle glaucoma including primary open-angle glaucoma, normal tension glaucoma, and exfoliation glaucoma without previous glaucoma surgeries. CCD was detected by swept-source anterior segment optical coherence tomography. Outcome measures were the course of IOP, the number of medications, and the postoperative complications of the CCD group compared with those of the non-CCD group.

Results

CCD appeared in 21 eyes (47.7%) within postoperative day 7 and disappeared within postoperative month 1 in 19 of 21 eyes. Although the IOP on postoperative day 1 in the CCD group (11.9 ± 7.7 mmHg) was significantly lower than that in the non-CCD group (19.2 ± 12.8 mmHg) (P = 0.020), the difference in the postoperative IOP between the groups decreased with time. No significant difference was seen in the number of medications and postoperative complications.

Conclusions

CCD occurred in approximately half of patients after 360S-LOT ab interno and may have the transient effect of lowering the IOP immediately after surgery. Postoperative CCD had no effect on the later IOP, the number of medications and postoperative complications throughout 12-month of follow-up.

Long-term follow-up of intraocular pressure and pressure-lowering medication in patients after ab-interno trabeculectomy with the Trabectome

BACKGROUND

The minimally invasive ab-interno trabeculectomy (AIT) via electro-ablation with the Trabectome has been on the European market since 2009. Many studies have proven the safety and efficacy of the procedure. Up until now, studies investigating the long-term effect of AIT have been sparse. In this study, we present long-term results of AIT in patients with primary and secondary open-angle glaucoma.

METHODS

In a retrospective monocentric study, the data of all the patients having undergone the procedure in 2010 at our institution were recorded. Data was collected during routine examinations at our institution. In total, 81 eyes of 74 patients (46 patients with primary open-angle glaucoma (POAG), 28 patients with pseudoexfoliative glaucoma (PEXG)) were included. At every examination, the intraocular pressure (IOP) was measured using Goldmann applanation tonometry and the number of IOP-lowering medication was registered. Statistical analysis was done using the Kaplan-Meier analysis or Dunnett's t test, respectively.

RESULTS

For both groups (POAG and PEXG), we found a significant lowering of the IOP (28% for POAG and 26% for PEXG) and a significant reduction of the number of IOP-lowering medication (32% for POAG and 29% for PEXG) after a median follow-up period of 3.5 years.

CONCLUSION

In patients with open-angle glaucoma and especially pseudoexfoliative glaucoma, ab-interno trabeculectomy is an effective surgical procedure to significantly lower the intraocular pressure on a long-term basis.

Supraciliary microstent implantation for open-angle glaucoma: multicentre 3-year outcomes

Objective

To describe the safety and effectiveness of CyPass supraciliary microstent implantation alone in eyes with open-angle glaucoma (OAG) followed up for up to 3 years.

Methods and analysis

This registry study included subjects with primary or secondary OAG who underwent CyPass Micro-Stent implantation alone at 12 sites in four European countries to reduce intraocular pressure (IOP) and/or use of IOP-lowering medications. The primary safety outcome was the incidence of adverse events. Secondary efficacy outcomes included mean changes from baseline in IOP and IOP-lowering medications. Eyes were subgrouped into those with low (< 21 mm Hg) and high (> 21 mm Hg) baseline IOP.

Results

This study included 225 eyes of 178 patients, with mean baseline IOP of 22.6 ± 6.7 mm Hg and a mean 2.2 ± 1.2 medications per eye. Common ocular adverse events included device obstruction (10.2%), IOP elevation > 10 mm Hg during follow-up (8.9%), retinal complications (4.4%) and loss of > 2 lines of best-corrected visual acuity (2.7%). Seventy-one eyes (31.6%) required secondary glaucoma surgery, with trabeculectomy (33 eyes) and second microstent implantation (13 eyes) being most common. At months 6–36, mean IOP reductions ranged from 4.4 to 5.1 mm Hg (15.8%–19.5%) and mean medication reductions from 0.2 to 1.2 (9.1%–54.5%). Mean IOP reduction was greater in eyes with higher than lower baseline IOP. Both subgroups showed reductions of 0.5–1.0 medication at 12–18 months.

Conclusion

CyPass microstent implantation demonstrated a safety profile consistent with other minimally invasive glaucoma surgeries and effectively lowered IOP for up to 3 years in eyes with OAG.

Evaluation of episcleral venous fluid wave during gonioscopy assisted transluminal trabeculotomy in patients with advanced glaucoma

PURPOSE

To evaluate episcleral venous fluid wave (EVFW) during GATT surgery in patients with advanced stage open angle glaucoma and to investigate its relationship with the severity of glaucoma.

METHODS

In all, 34 eyes of 28 open angle glaucoma patients who underwent GATT surgery were included into study. The extent of EVFW was evaluated using surgical records of patients and it was defined as number of clock hours. Correlations between the extent of EVFW and GAAT surgical outcomes as determined by intraocular pressures (IOP) and postoperative antiglaucoma medication needs were investigated. The impact of preoperative maximum IOP on EVFW was also evaluated.

RESULTS

There was a significant correlation between IOPs and the extent of the EVFW at 1st, 3rd, 6th and 12th months follow-up visits. 10 of (%29.4) 34 eyes required antiglaucoma medications after the surgery. Mean extents of EVFW in patients who needed and did not need medications during follow-ups were 2.6 ± 1.0 (1-4) and 5.9 ± 1.5 (3-8) clock hours and the difference was statistically significant. Cutoff value of <4.5 clock hours for the EVFW (sensitivity 79.2%, specifity 100%) was found to be associated with the need for additional antiglaucoma medication.

CONCLUSIONS

The extent of EVFW might be a valuable prognostic indicator for the surgical success of GATT since trabeculotomy is circumferential in this surgical technique making all collector channels accessible.

Five-year clinical outcomes of combined phacoemulsification and trabectome surgery at a single glaucoma center

PURPOSE

To analyze the 5-year results of trabectome ab interno trabeculectomy of a single glaucoma center.

METHOD

In this retrospective interventional single-center case series, data of 93 patients undergoing ab interno trabeculotomy between September 2010, and December 2012 were included. Kaplan-Meier analysis was performed using success criteria defined as postoperative intraocular pressure (IOP) ≤ 21 mmHg, and > 20% reduction from preoperative IOP, and no need for further glaucoma surgery. Risk factors for failure were identified using Cox proportional hazards ratio (HR).

RESULTS

The retention rate for 5-year follow-up was 66%. The cumulative probability of success at 1, 2, 3, 4, and 5 years was 82.6%, 76.7%, 73.9%, 72.3%, and 67.5%. Risk factors for failure were lower baseline IOP (HR = 0.27, P = 0.001), younger age (HR = 0.25, P = 0.02), and higher central corneal thickness (HR = 0.18, P = 0.01). Exfoliative glaucoma was associated with a higher success rate (HR = 0.39, P = 0.02). IOP was decreased significantly from 20.0 ± 5.6 mmHg at baseline to 15.6 ± 4.6 mmHg at 5-year follow-up (P = 0.001). The baseline number of glaucoma medications was 1.8 ± 1.2, which decreased to 1.0 ± 1.2 medications at 5 years.

CONCLUSION

Trabectome surgery was associated with a good long-term efficacy and safety profile in this single-center case series with a high retention rate.

Is Newer Necessarily Better? The Evolution of Incisional Glaucoma Surgery Over the Last 100 Years

PURPOSE

To examine the progress made in glaucoma incisional surgery and determine if there has been sufficient progress to meet the needs of glaucoma patients.

DESIGN

Perspective (literature review).

METHODS

This is a retrospective assessment of key milestones in the evolution of glaucoma incisional surgery and an evaluation of the risks and the benefits of these procedures. Benefits are defined as effective reduction in intraocular pressure (IOP) and protecting visual function, while risks are defined as safety and complications for our patients. Quality of life is also considered.

RESULTS

Although advances have been made in the last 100 years, the trabeculectomy, a procedure that was described more than 50 years ago, remains the optimal choice for reducing IOP among those patients who require pressures in the teens, who do not respond to medications and prior laser therapy.

CONCLUSIONS

Appropriate patient selection, careful attention to surgical technique, and intensive follow-up of patients will optimize the results of a trabeculectomy. Newer procedures must be carefully studied in well-designed clinical trials to determine comparative levels of safety and efficacy to this gold standard. Advances in drug delivery and minimally invasive glaucoma surgery may ultimately produce the best outcome for glaucoma patients in the future.

Two-year outcomes of ab interno trabeculectomy with the Trabectome for Chinese primary open angle glaucoma: a retrospective multicenter study

AIM

To evaluate the 2-year efficacy and safety of ab interno trabeculectomy with the Trabectome in Chinese primary open angle glaucoma (POAG) patients.

METHODS

This was a multicenter, retrospective, observational study and included POAG patients with or without visually-significant cataracts. The Chinese patients were enrolled from three glaucoma centers and a group of comparable Japanese POAG patients was analyzed from our international Trabectome database. The patients received Trabectome or a combined surgery with phacoemulsification and intraocular lens implantation. The primary outcome was intraocular pressure (IOP) reduction. Secondary outcomes included reduction of glaucoma medications, surgical complications, and success at 2y. Success was defined as: 1) IOP≤21 mm Hg and at least 20% IOP reduction from baseline after 3mo at any two consecutive visits; 2) no additional glaucoma surgery required.

RESULTS

A total of 42 Chinese POAG patients from three glaucoma centers were enrolled. Twelve patients underwent Trabectome surgery combined with phacoemulsification and intraocular lens implantation while the remainder underwent Trabectome surgery alone. Thirteen patients had a history of failed glaucoma surgery and were considered as complicated cases. In China data, the mean preoperative IOP was 21.4±1.23 mm Hg. The Trabectome lowered IOP to 17.9±1.8 mm Hg at 2y (P=0.05). The number of glaucoma medications also decreased significantly from a baseline of 2.0±0.9 to 1.1±0.8 at 2y post-surgery (P=0.04). The overall 2-year success rate was 78%, with patients undergoing combined surgery having a higher success rate compared with those undergoing Trabectome surgery alone (100% vs 76%). In Japan data, the mean preoperative IOP was 20.8±7.7 mm Hg. The Trabectome lowered IOP to 12.20±2.0 mm Hg at 2y. The number of glaucoma medications also decreased significantly from a baseline of 2.1±0.9 to 3.4±0.6 at 2y post-surgery. In all patients, no major complications were seen.

CONCLUSION

Surgery with the Trabectome appears to be an efficient and safe procedure in Chinese POAG patients in the long-term.

Combined glaucoma and cataract surgery: Comparison of viscocanalostomy, endocyclophotocoagulation, and ab interno trabeculectomy

PURPOSE

To compare outcomes of phacoemulsification combined with viscocanalostomy, endocyclophotocoagulation (ECP), or ab interno trabulectomy for intraocular pressure (IOP) control and safety in eyes with open-angle glaucoma and visually significant cataract.

SETTING

Farabi Eye Hospital, Tehran, Iran.

DESIGN

Retrospective case series.

METHODS

Medical records of patients who had combined surgery and were followed for at least 1 year were reviewed. Complete success, postoperative IOP, number of medications at each visit, and complications were evaluated and compared before and after adjustments for confounders.

RESULTS

Forty-six eyes had combined phacoviscocanalostomy, 35 had phaco-ECP, and 28 eyes phaco-ab interno trabulectomy. The groups were matched for baseline IOP (P = .24). At the final follow-up (mean 17.2 months ± 5.5 [SD]), the phacoviscocanalostomy group had the lowest mean IOP (13.5 ± 4.7 mm Hg, 29% decrease) (P = .01). There was no significant difference in the final IOP between phaco-ECP and phaco-ab interno trabulectomy (16.4 ± 3.9 mm Hg, 20% decrease versus 15.8 ± 4.2 mm Hg, 15% decrease) (P = .88). The reduction in the number of medications was greater with phacoviscocanalostomy (77%) than with phaco-ECP (40%) and phaco-ab interno trabulectomy (44%) (P = .01). Phacoemulsification-ab interno trabulectomy had the fewest complications. Intraocular pressure spikes were more frequent in the phaco-ECP group (20%) than in the other groups (4%) (P = .05).

CONCLUSIONS

All procedures significantly lowered IOP. Phacoemulsification-ab interno trabulectomy resulted in fewest complications and phacoviscocanalostomy led to the largest IOP drop and largest reduction of medications.