Relationship between selective laser trabeculoplasty and excisional goniotomy outcomes in glaucomatous eyes

Historical and Contemporary Debates in Schlemm's Canal-Based MIGS

Glaucoma is one of the primary causes of blindness worldwide. Canal opening surgery, a type of minimally invasive glaucoma surgery (MIGS) applied in cases of mild to moderate glaucoma, has gained increasing popularity in recent years due to its efficacy in reducing the intraocular pressure, its safety profile, the simplicity of its technique, and the reduced likelihood of compromised vision. Nevertheless, the existing body of histopathological studies remains insufficient for a comprehensive understanding of post-surgical wound healing. Consequently, debates persist among researchers regarding the mechanism through which Schlemm's canal opening surgery reduces the intraocular pressure, as well as the surgical techniques that may impact the outcomes and the factors influencing surgical success. As the history of MIGS is relatively short and lacks sufficient systemic reviews or meta-analyses evaluating the influence of individual factors, this review was conducted to illuminate the disparities in researchers' opinions at the current stage of research.

Influence of Laser Trabeculoplasty on Combined Phacoemulsification/Kahook Dual Blade Goniotomy

Purpose

To investigate the influence of laser trabeculoplasty (LTP) on subsequent surgery with combined phacoemulsification/Kahook Dual Blade goniotomy (phaco-KDB) in patients with open-angle glaucoma or intraocular hypertension.

Patients and Methods

Patients undergoing phaco-KDB between 2019 and 2021 were divided into previously LTP treated and previously non-LTP treated, and LTP-treatment included argon laser trabeculoplasty (ALT) and selective laser trabeculoplasty (SLT). The primary goal was to investigate if previous LTP influenced later surgical outcome of phaco-KDB. The secondary goal was to investigate if the outcome of LTP could be predictive of the outcome of subsequent phaco-KDB. We also compared IOP- and medication reductions between LTP and non-LTP treated patients.

Results

A total of 111 LTP treated patients were compared to 139 non-LTP treated patients. In LTP treated patients, surgical success of phaco-KDB was 82.9%, compared to 88.5% in non-LTP treated patients (P=0.20). Reductions in IOP and medications were similar between groups. Furthermore, within the LTP group, patients with successful LTP-treatment had a subsequent surgical success of phaco-KDB in 80.7%, compared to 83.0% in patients with unsuccessful LTP-treatment (P=0.765).

Conclusion

Previous LTP treatment does not predict the outcome of phaco-KDB. Furthermore, no correlation was found between the LTP effect and a later surgical success of phaco-KDB.

Risk Factors for Hyphema Following Kahook Dual Blade Goniotomy Combined With Phacoemulsification

PRCIS

Hyphema development after Kahook Dual Blade (KDB) excisional goniotomy was significantly associated with postoperative day 1 intraocular pressure (IOP) ≤12 mm Hg, male sex, and narrow iridocorneal angles, but not with continuation of anticoagulation or antiplatelet therapy.

PURPOSE

To identify risk factors of hyphema development after KDB goniotomy combined with phacoemulsification.

METHODS

In all, 202 eyes in 145 patients who received a KDB goniotomy combined with phacoemulsification between February 21, 2017 and February 18, 2020 were evaluated for preoperative factors that were predictive of postoperative hyphema. Hyphema was defined as the development of ≥1 mm layered blood in the anterior chamber. The primary outcome was the association between various preoperative factors and the development of postoperative hyphema. Binomial logistic regression was used to analyze risk factors of hyphema development while controlling for other variables.

RESULTS

Hyphema occurred in 8.4% (17/202) of patients on day 1 after KDB goniotomy combined with phacoemulsification. Male sex ( P =0.008), angle closure glaucoma ( P =0.036), and postoperative day 1 IOP ≤12 mm Hg ( P =0.049) were significantly correlated with hyphema development while controlling for other variables. Preoperative anticoagulation and antiplatelet therapy had no association with hyphema development ( P =0.538).

CONCLUSIONS

Postoperative hyphema was associated with male sex, narrow iridocorneal angles, and a postoperative day 1 IOP lower than typical episcleral venous pressure when controlling for other variables. Preoperative anticoagulation or antiplatelet therapy was not associated with developing postoperative hyphema in this study; however, further investigation is needed before recommendations can be made.

Netarsudil as a Predictor of Response for MicroPulse Transscleral Laser Therapy: A Pilot Study

PURPOSE

To investigate the role of netarsudil as an outcome predictor of MicroPulse transscleral laser therapy (MPTLT).

DESIGN

Retrospective comparative study.

SUBJECTS

Forty-seven eyes in 33 adult patients with glaucoma with a minimum of 1 month of follow-up after netarsudil treatment and 3 months of follow-up after MPTLT were included. Eyes receiving intraocular pressure (IOP)-lowering procedures in the interim were excluded.

INTERVENTION

Ophthalmic eyedrops of netarsudil at 0.02%, followed by MPTLT treatment.

MAIN OUTCOME MEASURES

Correlation of success between netarsudil and MPTLT. Netarsudil success was defined as an IOP reduction ≥ 20% from baseline, whereas MPTLT success was defined as an IOP reduction ≥ 20% without additional IOP-lowering medications. Secondary outcomes included success rates, mean IOP reduction, adverse effects after each treatment, and netarsudil discontinuation rate.

RESULTS

We found a positive correlation between the netarsudil response and the subsequent MPTLT response (odds ratio, 3.73; 95% confidence interval, 1.05-13.24; P = 0.041). Among netarsudil responders, 73.7% (14/19) of eyes subsequently responded to MPTLT, whereas among netarsudil nonresponders, 42.8% (12/28) of eyes subsequently responded to MPTLT (P = 0.037). From netarsudil, 44.4% of eyes were successful; from MPTLT, 55.3% of eyes were successful. The mean IOP reductions were 2.83 ± 5.74 mmHg from netarsudil and 3.15 ± 6.43 mmHg from MPTLT. Overall, the rate of netarsudil discontinuation was 55.3%. The most common reasons for netarsudil discontinuation were adverse effects (48.9%), followed by high cost (19.1%). The most common adverse effects to netarsudil were conjunctival hyperemia (48.9%) and blurred vision (8.5%). There were no adverse events reported after MPTLT. After MPTLT, 29.8% of eyes required additional IOP-lowering procedures.

CONCLUSIONS

The netarsudil response may serve as a predictive marker of the MPTLT response, with over 70% of netarsudil responders subsequently responding favorably to MPTLT in this study.

Comparison of Outcomes for Laser Trabeculoplasty after Kahook Dual Blade Goniotomy Versus in Goniotomy-Naive Eyes

Introduction

This was a comparison of laser trabeculoplasty (LTP) outcomes in eyes with prior Kahook Dual Blade (KDB) goniotomy versus in goniotomy-naive control eyes.

Methods

This was a retrospective matched comparative case series. We identified a cohort of patients undergoing LTP between February 2017 and July 2020 at University of Missouri. Patients were grouped by history of KDB goniotomy versus goniotomy-naivety as a control group. Inclusion criteria included age at least 18 years, minimum of 6 months follow-up after LTP, and minimum period of 6 months between KDB goniotomy and LTP. All KDB procedures were combined with uncomplicated phacoemulsification. Patients who had any additional intraocular pressure (IOP)-lowering procedures between KDB goniotomy and LTP were excluded. Patients in the control group received a single LTP procedure.

Primary outcome consisted of the comparison of LTP success, defined as IOP reduction of at least 20% or reduction of glaucoma medications from pre-LTP baseline. Secondary outcomes included IOP and medication reduction from pre-LTP baseline.

Results

Twenty-one eyes of 19 patients with history of KDB goniotomy and 42 eyes of 36 control patients without previous angle or laser procedures were included. Baseline characteristics including age, gender, ethnicity, type and severity of glaucoma, baseline IOP, and baseline medications were matched between groups. The LTP success rate was higher in the control group, but was not statistically significant (64% vs 57%, p = 0.58). IOP reduction was only significant in the control eyes (2.50 ± 4.0 mmHg, p = 0.01 vs 2.35 ± 4.7 mmHg, p = 0.08). The number of glaucoma medications was not significantly reduced in either group.

Conclusion

LTP may have a limited IOP- and medication-lowering effect in eyes with a history of KDB goniotomy compared to goniotomy-naive eyes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40123-021-00378-7.