Outcome of phacoemulsification combined with excisional goniotomy using the Kahook Dual Blade in severe glaucoma patients at 6 months

A Randomized Controlled Trial Comparing STREAMLINE Canaloplasty to Trabecular Micro-Bypass Stent Implantation in Primary Open-Angle Glaucoma

Purpose

To report interim results of the VENICE study, a multi-center, randomized, controlled trial (RCT) comparing STREAMLINE Surgical System (STREAMLINE) canaloplasty with iStent inject W (iStent W) implantation in patients with mild-to-moderate primary open-angle glaucoma (POAG) undergoing phacoemulsification.

Patients and Methods

Safety and efficacy analyses involving the first 72 randomized eyes are included in this report. Following pre- (Screening) and post-medication washout (Eligibility) visits, one eye per subject was randomized 1:1 to STREAMLINE or iStent W after undergoing uncomplicated phacoemulsification. Subjects were evaluated postoperatively at Day 1, Week 1, Month 1, 3, and 6. Intraocular pressure (IOP) measurements, number of IOP-lowering medications, and adverse events (AEs) were assessed at each follow-up visit.

Results

Seventy-two eyes were randomized; 35 underwent STREAMLINE canaloplasty and 37 were implanted with the iStent W. Seventy eyes completed their 6-month follow-up. Both the mean morning post-washout Baseline IOP between STREAMLINE 24.86±3.05 mmHg and iStent W 25.16±3.41 mmHg and the mean IOP at 6 months between STREAMLINE eyes 16.52±3.63 mmHg and iStent W eyes 16.08±3.19 mmHg were not statistically significantly different (p=0.691 and 0.596, respectively). At 6 months, more eyes were on zero glaucoma medications in the STREAMLINE group (81.8%) compared to the iStent W group (78.4%). In medication-free eyes, the mean IOP was reduced from 24.80±2.79 mmHg to 16.00±3.40 mmHg and 24.60±3.18 mmHg to 15.80±2.21 mmHg in the STREAMLINE and iStent W groups, respectively (p=0.752). Both groups showed reduction in IOP-lowering medications at every visit, compared to pre-washout (Screening), with STREAMLINE resulting in numerically fewer medications 0.20±0.48 compared to iStent W 0.40±0.79 at 6 months (P=0.384). AEs were mild and self-limited.

Conclusion

To our knowledge, the VENICE trial is the first RCT involving canaloplasty. These interim findings demonstrated comparable IOP and medication reduction between STREAMLINE canaloplasty and iStent W implantation, when combined with phacoemulsification.

Risk factors for hyphema following goniotomy or trabecular bypass stent placement combined with phacoemulsification

PURPOSE

To report the rates and risk factors for layered hyphemas after goniotomy (PG) and trabecular bypass stent (PTBS) surgery combined with phacoemulsification.

METHODS

Patient data was obtained using a retrospective chart review from adult patients (18 years of age or older) undergoing either PG or PTBS at the West Virginia University Eye Institute between 2013 and 2023. Generalized estimating equations were used to identify significant predictors of layered hyphema on post-operative day one. Predictors evaluated included age, race, glaucoma severity, glaucoma type, surgical time, complex cataract extraction, pre-operative intraocular pressure, post-operative day one intraocular pressure, peri-operative anti-thrombotic therapy (ATT) use, body mass index, and surgery type (i.e., PG or PTBS).

RESULTS

Of the 405 eyes from 279 patients included in the study, the overall layered hyphema rate was 10.1% in the whole sample. In multivariate generalized estimating equation model controlling for glaucoma stage and preoperative IOP, only surgery type (PG vs PTBS) predicted post-operative day one hyphema (β = 2.47, SE = 1.01, p = 0.02). The hyphema rates in the PG group and PTBS groups were 40/316 (12.7%) and 1/89 (1.1%), respectively. Eyes of patients on ATT had a hyphema rate of 16/189 (8.5%) compared to 25/216 (11.6%) in eyes of patients not on ATT.

CONCLUSIONS

Performing PG over PTBS was a significant predictor of a post-operative day one layered hyphema. No other systemic or ocular features, including the use of ATT, showed a statistically significant relationship with post-operative hyphemas.

KEY MESSAGES

What is Known. • The prevalence of minimally invasive glaucoma surgery has significantly increased in recent years. • Hyphema is a common postoperative complication of minimally invasive glaucoma surgery, however risk factors for hyphema in this setting have not been thoroughly evaluated.

WHAT IS NEW

• The use of perioperative antithrombotic therapy did not significantly increase the risk for postoperative hyphema following angle based minimally invasive glaucoma surgery. • Hyphema risk was significantly higher in patients undergoing goniotomy combined with phacoemulsification compared to trabecular bypass stent surgery with phacoemulsification.

Outcomes and risk factors for Kahook Dual Blade excisional goniotomy with concomitant phacoemulsification: a multicentre Canadian study

OBJECTIVE

To assess the outcomes and failure risk factors for Kahook Dual Blade (KDB) excisional goniotomy with cataract surgery (phaco-KDB) in eyes with various glaucoma subtypes and severities.

METHODS

This multisurgeon consecutive case series included glaucomatous eyes with cataract that underwent phaco-KDB and had a minimum follow-up of 12 months postoperatively. Efficacy was assessed by absolute and qualified surgical success (defined by different criteria) and changes in intraocular pressure (IOP) and antiglaucoma medication (AGM) at the last postoperative follow-up. Safety included best-corrected visual acuity, cup-to-disc ratio, visual field mean deviation, retinal nerve fibre layer thickness, and adverse events.

RESULTS

A total of 108 eyes of 89 patients with a median follow-up of 18 months (range, 12-47 months) were included. IOP decreased by 26% from 19.1 ± 5.0 mm Hg to 14.1 ± 3.5 mm Hg (p < 0.001), AGM use decreased by 29% from 2.4 ± 1.3 medications to 1.7 ± 1.3 (p < 0.001), and 25% of eyes became free of AGMs (vs 3% at baseline). Qualified success rates achieved for IOP cutoffs of 18, 15, and 12 mm Hg were 87%, 68%, and 46%, respectively. Higher baseline IOP and postoperative incidence of IOP spikes were associated with a higher risk of surgical failure. Best-corrected visual acuity improved postoperatively (p < 0.001), and visual field mean deviation, cup-to-disc ratio, and retinal nerve fibre layer thickness remained stable. Overall, safety was favourable, and adverse events were transient and not sight threatening.

CONCLUSION

This multicentre Canadian study provides real-world data that support the safety and efficacy of phaco-KDB in reducing IOP and AGM use with no evidence of disease progression during the follow-up period.

Outcomes of bent ab interno needle goniectomy with phacoemulsification in moderate to severe primary open angle glaucoma

PURPOSE

To assess the safety and efficacy of bent ab interno needle goniectomy (BANG) in moderate to severe primary open angle glaucoma (POAG) eyes undergoing phacoemulsification (phaco).

DESIGN

Single-arm, prospective, interventional study.

METHODS

POAG patients with medically uncontrolled intraocular pressure (IOP), >15 mmHg for moderate and >12 mmHg for severe POAG, with visually significant cataract were recruited. All patients underwent BANG using a 26-gauge needle to excise 30° of the trabecular meshwork, along with phaco. Primary outcome was IOP. Secondary outcomes were success rate, percentage reduction in IOP/antiglaucoma medications (AGMs), and intraoperative complications. Success at 12 months was defined as: criterion A: IOP <15 mmHg for moderate glaucoma or <12 mmHg for severe glaucoma with or without AGMs OR criterion B: reduction in number of AGMs by >1.

RESULTS

Thirty-two eyes of 32 patients underwent BANG + phaco. Mean age of the participants was 62.7 ± 8.4 years and there were 25 males and seven females. At 12 months, a significant decrease was noted in both IOP (from 17.6 ± 3.6 to 12 ± 1.6 mmHg, 31.8%; P < 0.001) and AGMs (from 3.7 ± 0.9 to 2.8 ± 0.8, 24.3%; P < 0.001). Twenty percent or more reduction in IOP was achieved in 62.5% (20/32) of eyes. Overall success (meeting either of the criteria A or B) at 12 months was achieved in 87.5% eyes. Mild postoperative hyphema was noted in 10 (31.2%) eyes, and two eyes (6.2%) required additional filtration surgery at 7 months.

CONCLUSION

A 30-degree BANG with phaco in patients of POAG appears to be a safe, effective and affordable MIGS for developing countries.

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.

Long-Term Efficacy of Successful Excisional Goniotomy with the Kahook Dual Blade

Purpose

To report clinical outcomes of successful excisional goniotomy with the Kahook Dual Blade (KDB), through 60 months.

Patients and methods

This was a noncomparative, single-surgeon, retrospective review of eyes receiving successful KDB goniotomy with or without concomitant phacoemulsification between October 2015 and January 2016 with five years of uninterrupted follow-up. Intraocular pressure (IOP), number of glaucoma medications, best corrected visual acuity (BCVA), and complications were recorded. Primary outcomes included changes from baseline in IOP, medication use, and BCVA, through five years.

Results

Fifty-two eyes of 28 patients were analyzed. Most eyes had mild primary open angle glaucoma (73%). Of the eyes analyzed, 41 underwent combined surgery and 11 underwent standalone surgery. With all eyes combined, mean (standard deviation) baseline IOP was 21.0 (4.1) mmHg and mean baseline medication use was 1.8 (1.1) medications per eye. Across time points at months 6, 12, 24, 36, 48, and 60, mean postoperative IOP ranged from 13.0 to 13.7 mmHg, representing mean reductions of 7.3-8.0 mmHg (34.7-38.3%; p <0.0001 at every time point). Similarly, mean medication use ranged from 0.4 to 0.6 medications per eye, representing mean reductions of 1.2-1.4 medications (66-75.5%; p <0.0001 at every time point). Mean logMAR BCVA improved from 0.321 (0.177) preoperatively to 0.015 (0.035) at month 60 (p < 0.0001).

Conclusion

In eyes not requiring secondary surgical procedures (eg, long-term surgical successes), excisional goniotomy provided clinically and statistically significant reductions in both IOP and the need for medications that were highly consistent through five years of follow-up. KDB goniotomy appears to be highly successful in Caucasian patients with open angle glaucoma on ≥1 IOP-lowering medications at baseline and with no history of prior ocular surgery. Successful excisional goniotomy with the KDB can be expected to improve long-term glaucoma-related visual outcomes through IOP reduction and to improve quality of life through medication reduction.

Outcomes of iStent Inject Versus Kahook Dual Blade Surgery in Glaucoma Patients Undergoing Cataract Surgery

PRCIS

iStent Inject implantation (iStent) or Kahook Dual Blade goniotomy (KDB) in combination with phacoemulsification have a similar IOP-lowering effect in all stages of glaucoma, and medications are significantly reduced, especially after KDB.

PURPOSE

To compare the 2-year efficacy and safety of iStent or KDB in combination with phacoemulsification in eyes with mild to advanced open angle glaucoma.

METHODS

A retrospective chart review of 153 patients that received iStent or KDB in combination with phacoemulsification at a single center between March 2019 and August 2020. The main outcome parameters at 2 years were: (1) intraocular pressure (IOP)-reduction ≥20%, with a postoperative IOP ≤18 mm Hg, and (2) a reduction of ≥1 medication. Results were stratified by glaucoma grade.

RESULTS

After 2 years, mean IOP was reduced from 20.3±6.1 to 14.2±4.1 mm Hg in the phaco-iStent group ( P <0.001) and from 20.1±6.1 to 14.7±3.6 mm Hg in the phaco-KDB group ( P <0.001). The mean number of medications was reduced from 3.0±0.9 to 2.6±1.1 in the Phaco-iStent group ( P =0.001) and from 2.3±1.0 to 1.5±1.3 in the Phaco-KDB group ( P <0.001). Success regarding IOP-reduction ≥20% with a postoperative IOP ≤18 mm Hg was met by 46% in the phaco-iStent group and by 51% in the phaco-KDB group. A reduction of ≥1 medication was met by 32% in the phaco-iStent group and by 53% in the phaco-KDB group ( P =0.013). Eyes with mild to moderate and advanced glaucoma responded equally well to the success criteria.

CONCLUSIONS

iStent and KDB, in combination with phacoemulsification, both lowered IOP effectively in all stages of glaucoma. More medications were reduced after KDB, suggesting that it may be a more effective procedure compared with iStent.

Factors associated with 1-year outcomes and transient intraocular pressure elevation in minimally invasive glaucoma surgery using Kahook Dual Blades

In this retrospective case-control study, we aimed to investigate the mid- to long-term outcomes and factors involved in minimally invasive glaucoma surgery using the Kahook Dual Blade. Of the 229 cases since 2018 in which the dual blades were used for glaucoma surgery at the Tenri Hospital, 133 eyes of 98 patients who followed up for more than 3 months were included. Intraocular pressure (IOP), number of drops score, and need for reoperation were evaluated on day 1 and at 1, 3, 6, 9, and 12 months postoperatively. Intraocular pressure spikes occurred in 25 patients postoperatively (18.8%), occurring at approximately 4.5 days (1-10.25). The preoperative number of eye drops used and ocular axial length were found to be associated with the occurrence of spikes (OR = 1.45, 95% CI 1.02-2.06; P = 0.025 and OR = 1.41, 95% CI 0.98-1.25; P = 0.072, respectively). At the 12-month mark, no significant relationship was found between the presence of spikes or incisional extent scores and the amount of change in IOP and number of drops scores. Patients with severe visual field impairment, high preoperative IOP and drop scores, and long ocular axial length may require more frequent follow-ups after surgery to check for spikes.

[Ab interno trabeculotomy without/with cataract operation-An alternative treatment before or instead of trabeculectomy in patients with high intraocular pressure?]

BACKGROUND

Trabeculotomy with the Kahook knife is a new ab interno minimally invasive glaucoma surgery (MIGS) procedure. The MIGS are usually performed in early to intermediate glaucoma eyes. In this retrospective study we analyzed the intraocular pressure (IOP) and topical glaucoma eye drop therapy (Meds) reduction achieved by the Kahook trabeculotomy (TO) without (n = 19) or with (n = 18) combined cataract operation (Cat-TO) as initial treatment before or to avoid filtering surgery.

MATERIAL AND METHODS

A total of 37 eyes of 37 patients were examined when IOP was > 21 mm Hg in at least 2 examinations despite the maximum tolerable Meds applied. Cat-TO was performed in 18 phakic eyes (primary open-angle glaucoma, POAG = 11, pseudoexfoliation glaucoma, PEX = 5, ocular hypertension, OHT = 2). In 19 pseudophakic eyes (POAG = 12, PEX = 6, OHT = 1) an isolated TO was executed. Complete success (no Meds) and relative success (irrespective of Meds) for IOP ≤ 21 mm Hg, ≤ 18 mm Hg, ≤ 16 mm Hg were evaluated 2, 6 and 12 months postoperatively.

RESULTS

The IOP was significantly reduced from preoperatively to 2 months after Cat-TO as well as after TO (Cat-TO: 26.8 ± 5.9 mm Hg to 16.0 ± 2.9 mm Hg, p < 0.001; TO: IOD 28.2 ± 5.6 mm Hg to 16.3 ± 3.5 mm Hg, p < 0.001). Meds reduction after Cat-TO as well as after TO was not significant (Cat-TO: 2.1 ± 1.3 to 1.3 ± 1.3, p = 0.11; TO: Meds 2.7 ± 1.1 to 2.2 ± 1.3, p = 0.23); however, Meds reduction after 6 and 12 months was significantly greater in the Cat-TO group compared to the TO group (p = 0.02). The IOP and Meds did not change significantly from 2 to 6 months. After Cat-TO, qualified success after 12 months for IOP ≤ 18 mm Hg was 61% (11/18) and for IOP ≤ 16 mm Hg 28% (5/18). After TO, qualified success after 12 months for TO was 47% (9/19) for IOP ≤ 18 mm Hg and 26% (5/19) for IOP ≤ 16 mm Hg. The intervention was not sufficient for 7 patients after TO and 2 patients after Cat-TO (IOP two times > 21 mm Hg).

CONCLUSION

The first year results show that TO as well as Cat-TO are effective minimally invasive interventions to delay or even avoid a filtrating operation. In case of Meds intolerance and target IOP ≤ 16 mm Hg Cat-TO is not sufficient.

Three-Year Outcomes of a Schlemm Canal Microstent (Hydrus Microstent) with Concomitant Phacoemulsification in Open-Angle Glaucoma

PURPOSE

HORIZON trials have reported the medium- and long-term outcomes of the Hydrus microstent. However, outside of randomized clinical trials, outcomes beyond 24 months have not been previously reported. Here, we examine the 3-year outcomes of the Hydrus microstent with cataract surgery outside of a randomized clinical trial setting.

DESIGN

Single-surgeon consecutive case series.

PARTICIPANTS

Glaucomatous eyes that underwent implantation of a Hydrus microstent with concomitant cataract surgery at a single ophthalmology center in Montreal, Canada.

METHODS

Success was defined according to the absence of specific failure criteria: (A) glaucoma reoperation; (B) selective laser trabeculoplasty; (C) intraocular pressure (IOP) < 5 mmHg, > 18 mmHg, or increase in the number of antiglaucoma medications (AGMs) used (after the first postoperative month), or loss of light perception due to glaucoma; (D) aggregation of criteria A-C. Predictors of treatment failure and postoperative changes in IOP and AGM use were assessed. Safety included best-corrected visual acuity (BCVA), cup-to-disc ratio (CDR), retinal nerve fiber layer (RNFL) thickness, ganglion cell inner plexiform layer (GC-IPL) thickness, visual field mean deviation (VF-MD) and pattern standard deviation (VF-PSD), and adverse events.

MAIN OUTCOME MEASURES

Surgical success, predictors of treatment failure, postoperative changes in IOP and AGM use, and structural and functional markers of disease stability.

RESULTS

One hundred six eyes were included. The 3-year surgical success according to Criteria A to D was 86%, 83%, 91%, and 67%, respectively. Intraocular pressure decreased by 26.5% from 18.9 ± 4.8 to 13.9 ± 2.3 mmHg (P < 0.001) and AGM use reduced by 33% from 3.0 ± 1.2 to 2.0 ± 1.2 medications (P < 0.001). The postoperative improvement in BCVA was preserved (P < 0.001). The structural and functional markers of disease stability, including CDR, RNFL, and GC-IPL thickness, as well as VF-MD and VF-PSD, remained stable (P > 0.05). Postoperative adverse events were few and transient.

CONCLUSIONS

The 36-month results from this study show that the Hydrus microstent with phacoemulsification is safe and effective in reducing the IOP and AGM among patients with mild to severe open-angle glaucoma and can slow down the disease progression by preserving both structural and functional parameters.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

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.

Outcomes and risk factors for ab interno trabeculotomy with a Kahook Dual Blade

PURPOSE

To verify the surgical results and risk factors for ab interno trabeculotomy using a Kahook Dual Blade (KDB-LOT) in patients with various glaucoma types.

METHODS

This study was a retrospective case series of 205 eyes that underwent KDB-LOT. For Kaplan-Meier survival analysis, criterion A was defined as a ≤ 20% reduction in intraocular pressure (IOP) from baseline. Criteria B, C, and D were IOPs of ≤ 21, 18, and 15 mmHg, respectively. The Cox proportional hazard (CPH) model investigated prognostic factors.

RESULTS

The mean (SD) IOP decreased from 24.7 (7.98) to 17.6 (4.80) mmHg in all cases, from 21.3 (6.88) to 17.8 (3.52) mmHg in primary open-angle glaucoma (POAG), from 25.4 (7.32) to 17.1 (4.65) mmHg in exfoliation glaucoma, from 30.6 (8.88) to 17.8 (8.29) mmHg in uveitic glaucoma, and from 30.8 (7.29) to 17.3 (0.83) mmHg in steroid-induced glaucoma at 1 year after KDB-LOT. The Kaplan-Meier survival analysis showed that patients with POAG had the best prognosis under criteria B and C, and the 1-year survival rate in patients under criterion D was less than 35% for any disease type. CPH analysis revealed that age and KDB-LOT with phacoemulsification were good prognostic factors. Risk factors for surgical failure were previous cataract surgery, selective laser trabeculoplasty, and postoperative peripheral anterior synechiae.

CONCLUSION

KDB-LOT was effective in treating patients with several glaucoma types but showed difficulty in pushing IOP below 15 mmHg. Prognostic factors should be considered when making decisions regarding surgical indications.

Risk factors of surgical failure in combined phacoemulsification and excisional goniotomy for angle-closure glaucoma

PURPOSE

To evaluate the therapeutic success, and risk factors for combined phacoemulsification and Kahook Dual Blade excisional goniotomy (Phaco/KDB) in primary angle-closure glaucoma (PACG).

METHODS

A retrospective review was conducted on glaucoma patients who underwent Phaco/KDB between September 2019 and August 2021 at 2 ophthalmology centers. Complete success was defined as unmedicated intraocular pressure (IOP) ≤ 18 mmHg with no further glaucoma surgery, while the medicated IOP ≤ 18 mmHg was defined as qualified success with lesser medications than at baseline.

RESULTS

Seventy-two eyes (64 patients) with a mean age of 67.1 ± 8.1 years were included in this study, and 70.2% were female. The mean medicated baseline IOP decreased from 23.4 ± 8.1 to 16.6 ± 3.9 mmHg at an average of 11.6 ± 3.7 months of follow-up (- 29.1%; P < 0.00). Medications decreased from 2.6 ± 1.3 to 0.4 ± 0.9 (- 82.6%; P < 0.001). Complete success and qualified success were achieved in 65.3% and 79.2% of eyes, respectively. Male gender [hazard ratio (HR): 6.00 (1.57-22.9); P = 0.009] was observed a risk factor for surgical failure, whereas higher axial length (HR:0.37 (0.16-0.86); P = 0.021), and a combined circumferential goniosynechialysis procedure (HR: 0.13 (0.02-0.74); P = 0.022) lowered the risk of surgical failure. Hyphema, postoperative shallowing anterior chamber, and IOP spike were the most common complications. The cumulative survival proportion for qualified success at 12 months was 82.5% ± 0.05 (95% CI, 0.70-0.90).

CONCLUSION

Phaco/KDB provided acceptable therapeutic success rate and may, therefore, be recommended in patients with coexisting cataract and PACG. Identifying patients with risk factors preoperatively may help clinicians predict surgical success.

Coarsened Exact Matching of Excisional to Plasma-ablative Ab Interno Trabeculectomy

Aim

To compare ab interno trabeculectomy by trabecular meshwork (TM) excision to plasma-mediated ablation in primary open-angle glaucoma (POAG) patients.

Methods

Retrospectively collected data of TrabEx+ (TEx) (n = 56) and Trabectome (T) (n = 99) patients were compared by coarsened exact matching to reduce confounding and matched based on baseline intraocular pressure (IOP) and age. The primary outcomes were IOP and the number of glaucoma medications. Complications and the need for additional glaucoma surgery were assessed. Patients were followed for up to 1 year.

Results

A total of 53 TEx could be matched to T. Baseline IOP was 16.5 ± 4.6 mm Hg in both; age was 73.7 ± 8.8 and 71.5 ± 9.9 years in TEx and T, respectively. TEx was taking more medications than T (p < 0.001). IOP was reduced to 14.8 ± 4.3 in TEx and to 13.4 ± 3.4 in T at 6 months, and to 14.9 ± 6.0 (p = 0.13) in TEx and to 14.1 ± 3.8 mm Hg (all p < 0.05) in T at 12 months. Medications were reduced at both 6 and 12 months (p < 0.05). No differences were seen between TEx and T at 6 and 12 months. In TEx, only one serious complication occurred, and two patients required further glaucoma surgery.

Conclusion

Although both groups had a baseline IOP considered low for ab interno trabeculectomy, IOP and medications were reduced further at 6 and 12 months. IOP reduction did not reach significance in TEx at 12 months. The intergroup comparison did not reveal any significant differences. Both had a low complication rate.

Clinical significance

This study investigated subtle differences between a plasma-ablative device, the T, and an excisional device, the TEx, by applying coarsened exact matching. IOP and medications were reduced in both groups at 6 and 12 months, although IOP reduction did not reach significance in TEx at 12 months. The intergroup comparison did not reveal any significant differences, with both devices having a low complication rate.

How to cite this article

Dakroub M, Verma-Fuehring R, Strzalkowska A, et al. Coarsened Exact Matching of Excisional to Plasma-ablative Ab Interno Trabeculectomy. J Curr Glaucoma Pract 2023;17(1):9-14.

Kahook Dual-Blade Goniotomy with and without Phacoemulsification in Medically Uncontrolled Glaucoma

Purpose

To evaluate the 2-year efficacy and safety of Kahook dual-blade (KDB) goniotomy in patients with medically uncontrolled glaucoma.

Methods

This was a retrospective case-series study of 90 consecutive patients with primary open-angle glaucoma (POAG) or pseudoexfoliation glaucoma (PEXG) that underwent KDB goniotomy alone (KDB-alone group) or KDB goniotomy in combination with phacoemulsification (KDB-phaco group) during 2019-2020. All patients were uncontrolled on three or more medications. Surgical success was defined as an IOP reduction ≥20% and/or a reduction of one or more medications at 24 months. We also report IOP levels and number of medications from baseline to 24 months, as well as the need for further glaucoma interventions.

Results

At 24 months, mean IOP had reduced from 24.8±8.3 to 15.0±5.3 mmHg in the KDB-alone group (P<0.001) and from 22.3±5.8 to 13.9±3.0 mmHg in the KDB-phaco group (P<0.001). Medications had reduced from 3.5±0.6 to 3.1±0.9 in the KDB-alone group (P=0.047) and from 3.3±0.5 to 2.3±1.1 in the KDB-phaco group (P<0.001). An IOP reduction ≥20% and/or a reduction with one or more medications was achieved by 47% of eyes in the KDB-alone group and by 76% of eyes in the KDB-phaco group. Eyes with PEXG and POAG responded equally well to the success criteria. During the 24-month follow-up, additional glaucoma surgery or transscleral photocoagulation was performed in 28% of eyes in the KDB-alone group and in 12% of eyes in the KDB-phaco group.

Conclusion

In patients with medically uncontrolled glaucoma, KDB had a significant IOP-lowering effect after 24 months, but success rates were higher when KDB was performed in combination with cataract surgery compared to stand-alone treatment.

Three-year clinical outcomes of phacoemulsification combined with excisional goniotomy using the kahook dual blade for cataract and open-angle glaucoma in Saudi Arabia

PURPOSE

The aim of this study was to describe the changes in intraocular pressure (IOP), IOP-reducing drugs, and visual acuity (VA) through up to 3 years of follow-up in patients undergoing combined phacoemulsification and excisional goniotomy with the Kahook Dual Blade (KDB-phaco) by a single surgeon in Saudi Arabia.

METHODS

The health records of 55 eyes of 47 patients undergoing KDB-phaco by a single surgeon were reviewed. Data were extracted from visits occurring preoperatively (n = 55), intraoperatively (n = 55), and 1-day (n = 55), 2 weeks (n = 55), 4-6 weeks (n = 49), 2-3 months (n = 55), and 6 (n = 55), 9 (n = 55), 12 (n = 55), 18 (n = 49), 24 (n = 46), and 36 months (n = 16) postoperatively. Data collection included IOP, IOP-lowering medications, and VA at each time point. Adverse events were also collected. Paired t-tests were used to compare IOP, medications, and VA at each time point to preoperative values.

RESULTS

Mean (standard error) baseline IOP was 20.4 (0.7) mmHg and through up to 36 months of follow-up (minimum 12 months, mean 26.1 [1.0] months) ranged from 13.6 to 14.1 mmHg; significant reductions (P < 0.0007) of 5.7-7.0 mmHg (23.0%-29.5%) were achieved at every time point. Medications were reduced from 3.2 (0.1) to 0.2-2.0 (reductions of 1.2-3.1 medications [50.0%-94.9%]; P < 0.0001 at every time point). At months 24 and 36, the mean IOP was 13.9 (0.3) and 13.9 (0.5) mmHg and mean medications were 1.4 (0.2) and 2.0 (0.4). Mean logMAR VA improved from 1.0 (0.1) preoperatively to (0.2 [0.0]; P < 0.001) by month 6 and remained stable thereafter through the duration of follow-up.

CONCLUSION

KDB-phaco significantly lowered IOP approximately 30% by day 1 with consistency and durability through 3 years. Medication use was reduced by >50% through 36 months. Mean logMAR VA improved from 1.0 to 0.2 (Snellen equivalent 20/200-20/32). This procedure provides meaningful long-term reductions in IOP and the need for IOP-lowering medications without compromising visual rehabilitation in Saudi Arabian eyes with cataract and glaucoma.

Six months' follow-up of combined phacoemulsification-kahook dual blade excisional goniotomy

PURPOSE

This study reports on the combination of excisional goniotomy and cataract extraction in the management of glaucoma in terms of intraocular pressure (IOP) and glaucoma medication reduction.

METHODS

This is a retrospective case series. Twenty-eight eyes of 22 patients with the diagnosis of cataract and ocular hypertension or glaucoma of any stage underwent combined phacoemulsification and Kahook Dual Blade (KDB) goniotomy, between March 2019 and September 2020. The parameters evaluated were postoperative best-corrected visual acuity, mean IOP reduction, number of IOP-lowering medications, and the surgical success rate defined as IOP reduction >20% and/or reduction in glaucoma medications >1.

RESULTS

The mean IOP reduction at 6 months was 4.5 mmHg (P = 0.0007), which translates to 24.9% reduction from preoperative IOP. The mean preoperative number of glaucoma medications was 2.9 ± 1.0 (median of 3). It was reduced to 1.1 ± 1.1 (median of 1.5), 1.46 ± 1.17 (median of 2), 1.44 ± 1.28 (median of 2), and 1.56 ± 1.28 (median of 2) at 1 week, 1 month, 3 months, and 6 months, respectively. Twenty-nine percent (8/28) of the patients were off glaucoma medications at 6 months and 46% (13/28) had a reduction of more than 50% of their glaucoma medications.

CONCLUSION

Combined phacoemulsification-KDB excisional goniotomy may be an effective and safe alternative to more invasive filtering surgery in glaucoma patients of any stage.

Risk factors for intraocular pressure elevation in a six-month period after ab interno trabeculotomy using a Kahook Dual Blade

BACKGROUND

To examine the risk factors for an early postoperative intraocular pressure (IOP) increase after ab interno trabeculotomy using a Kahook Dual Blade (KDB trabeculotomy).

METHODS

A retrospective study was performed in 76 exfoliation glaucoma (EXG) eyes and 56 primary open angle glaucoma (POAG) eyes that underwent KDB trabeculotomy, with or without cataract surgery at Kumamoto University Hospital. Postoperative high IOP was classified as IOP≥20 mmHg (within three months after surgery, whether persistent or temporary), transient IOP≥20 mmHg (IOP≥20 mmHg after surgery, then dropped below 20 mmHg), and the presence of IOP spikes (≥ 10 mmHg from baseline). Risk factors were examined using logistic regression analysis.

RESULTS

The preoperative mean IOP (SD) was 24.98 (7.23) mmHg in patients with EXG and 21.28 (6.58) mmHg in patients with POAG. IOP was reduced by 32.1% in patients with EXG and by 17.7% in patients with POAG at 6 months after surgery. Postoperative IOP≥20 mmHg was observed in 56.6% of EXG patients and in 51.8% of POAG patients. IOP spikes occurred in 15.8% of EXG patients and in 14.3% of POAG patients. Logistic regression analysis showed that factors with significant odds ratios (ORs) were age (OR = 0.866, 95% CI = 0.793-0.945), preoperative medication use (OR = 2.02, 95% CI = 1.17-3.49), trabeculotomy in combination with cataract surgery (OR = 0.0674, 95% CI = 0.015-0.303), and IOP at day 1 (OR = 1.41, 95% CI = 1.18-1.68) for postoperative IOP≥20 mmHg, the IOP at day 1 (OR = 1.1, 95% CI = 1.03-1.17) for transient IOP≥20 mmHg, and age (OR = 0.948, 95% CI = 0.901-0.997) and preoperative IOP (OR = 0.83, 95% CI = 0.736-0.936) for IOP spikes.

CONCLUSION

Although KDB trabeculotomy is an effective treatment for patients with EXG and POAG, patients who take multiple preoperative medications and have a high IOP on day 1 require careful follow-up to prevent postoperative IOP elevation.

Predictive Factors of Outcomes in Kahook Dual Blade Excisional Goniotomy Combined with Phacoemulsification

Aim

To identify factors that were significant predictors of Kahook Dual Blade (KDB) excisional goniotomy outcomes.

Materials and methods

One hundred and thirty-two eyes from 99 adult glaucoma patients who underwent combined KDB and phacoemulsification (KDB-phaco) with a minimum 6-month follow-up were assessed for baseline patient characteristics to determine correlation to the success of KDB-phaco at 6 and 12 months postoperatively. Success was defined as ≥20% intraocular pressure (IOP) reduction or ≥1 medication reduction as well as IOP ≤18 mm Hg without any additional IOP-lowering procedures after KDB-phaco.

Results

63.6% (84/132) and 46.1% (41/89) of cases were successful at the 6- and 12-month follow-ups, respectively. KDB-phaco reduced patient's preoperative IOP (in mm Hg) from 17.6 ± 4.6 to 14.9 ± 3.2 at 6 months (15.3%, p < 0.001) and 15.4 ± 4.7 at 12 months (12.5%, p = 0.001). KDB-phaco reduced patient's preoperative IOP-lowering medications from 2 ± 1.2 to 1.1 ± 1.2 at 6 months (45%, p < 0.001) and 1.32 ± 1.3 at 12 months (34%, p < 0.001). At 6 months, patients on >1 IOP lowering medication had a greater chance of meeting our success criteria (p = 0.037). Visually significant postoperative hyphema was not associated with the use of anticoagulation (p = 0.943) but was significantly associated with postoperative day 1 IOP ≤ 10 mm Hg (p = 0.011).

Conclusion

Patients who underwent KDB-phaco significantly reduced their IOP and medication burden at both 6 and 12 months compared with their baseline preoperative values. KDB-phaco outcome was associated with higher baseline IOP-lowering medications and increased rate of hyphema was associated with lower postoperative day 1 IOP, regardless of anticoagulation status. Age, ethnicity, prior laser trabeculoplasty, type and severity of glaucoma, and baseline preoperative IOP were not associated with surgical success.

Clinical significance

Patients with a higher number of baseline medications may experience a greater probability of success following KDB-phaco.

How to cite this article

Pratte EL, Cho J, Landreneau JR, et al. Predictive Factors of Outcomes in Kahook Dual Blade Excisional Goniotomy Combined with Phacoemulsification. J Curr Glaucoma Pract 2022;16(1):47-52.

Outcomes of combined single-use dual blade goniotomy and cataract surgery

Purpose

Single-use dual blade goniotomy (SBG) is a novel ab interno procedure that removes three to five clock hours of trabecular meshwork (TM). We analysed the reduction of intraocular pressure (IOP) and topical glaucoma medication (Meds) in eyes following combined cataract surgery and SBG (Cat-SBG).

Methods

IOP and Meds were evaluated retrospectively in 55 eyes of 38 patients. 44 eyes had high tension glaucoma (HTG) and eleven eyes had normal tension glaucoma (NTG). Complete success (no Meds) and qualified success (with Meds) for IOP levels ≤ 21, ≤ 18 , ≤ 16 mmHg or ≥ 20% IOP reduction at the two- and six-month follow-up were evaluated.

Results

IOP and Meds were significantly reduced from before to two months after Cat-SBG in HTG- and NTG-patients (HTG: IOP 19.4 ± 3.3 to 15.1 ± 3.3 mmHg; p < 0.001; Meds 2.1 ± 1.3 to 0.8 ± 1.3; p < 0.001; NTG: IOP 14.0 ± 2.3 to 11.5 ± 2.3 mmHg; p = 0.004; Meds 1.6 ± 0.7 to 0.3 ± 0.7; p < 0.001). IOP and Meds did not change significantly from two to six months after Cat-SBG.

In HTG, complete and qualified success rates were 43% (19/44) and 93% (41/44) for IOP ≤ 18 mmHg, 36% (16/44) and 64% (28/44) for IOP ≤ 16 mmHg and 30% (13/44) and 43% (19/44) for ≥ 20% IOP reduction six months after surgery. In NTG, complete and qualified success was 81% (9/11) and 100% (11/11) for IOP ≤ 18 and ≤ 16 mmHg, and 27% (3/11) for IOP reduction ≥ 20%.

IOP and Meds reduction were comparable between HTG and NTG eyes.

Only minor postoperative complications occurred.

Conclusion

Cat-SBG is an efficient method to significantly lower IOP in patients with HTG and NTG.

Response to netarsudil in goniotomy-treated eyes and goniotomy-naïve eyes: a pilot study

PURPOSE

To compare the intraocular pressure (IOP)-lowering effects of netarsudil on goniotomy-treated eyes versus goniotomy-naïve control eyes.

METHODS

Retrospective cohort study of 70 eyes from 49 adult glaucoma patients treated with netarsudil. Thirty-five eyes received sectoral goniotomy using Kahook Dual Blade (KDB) combined with cataract surgery with minimum of 3 months prior to netarsudil treatment. Thirty-five eyes in the control cohort received only cataract surgery prior to netarsudil. Primary outcome was treatment success, defined as ≥ 20% decrease in IOP at minimum 1 month follow-up. Secondary outcome measures included percent of IOP reduction, adverse effects of medication, medication discontinuation rate, and relationship between KDB goniotomy response and netarsudil response.

RESULTS

Eighty-three percent of KDB-treated eyes achieved netarsudil treatment success compared to 54% of control eyes (P = .012). IOP reduction was 30.3 ± 16.2% (IQR 21-38%) in KDB-treated eyes and 19.4 ± 12.4% (IQR 9.2-30.8) in control eyes (P = .007). History of prior KDB increased the likelihood of success to netarsudil treatment compared to eyes without prior KDB, regardless of surgical response to KDB (odds ratio 4.51, 95% CI 1.34-15.14, P = .015). The overall rate of adverse effects of netarsudil was 42%, most commonly reported as conjunctival hyperemia, allergy, and blurred vision.

CONCLUSIONS

Netarsudil had a greater IOP-lowering effect in eyes treated with prior goniotomy and may serve as a promising adjunctive ocular hypotensive agent to further reduce IOP in eyes with prior goniotomy.

Long-Term Outcomes of a Kahook Dual Blade Procedure Combined with Phacoemulsification in Japanese Patients with Open-Angle Glaucoma

We retrospectively evaluated the long-term surgical outcomes of phacoemulsification combined with a Kahook dual blade (KDB) procedure in Japanese patients with open-angle glaucoma. The primary outcome was surgical success or failure. Surgical failure was indicated by a <20% reduction in preoperative intraocular pressure (IOP) or IOP > 18 mmHg (criterion A), IOP > 14 mmHg (criterion B), or requirement for reoperation. Glaucoma medications after surgery and postoperative complications were recorded. Surgical outcomes were compared between primary open-angle glaucoma (POAG) and exfoliation glaucoma (ExG) groups. The probability of success at 36 months postoperation was 52.5% using criterion A and 36.9% using criterion B. Mean IOP decreased significantly from 19.5 ± 6.9 mmHg preoperatively to 11.9 ± 2.7 mmHg at 36 months, and the mean number of glaucoma medications from 2.4 ± 1.4 to 1.6 ± 1.4 (both p < 0.01). IOP spikes were significantly more common in the ExG group (23.7% vs. 9.1%; p = 0.045), as was the need for additional glaucoma surgery (10.5% vs. 1.8%; p = 0.038). A KDB procedure combined with cataract surgery resulted in significant long-term decreases in IOP and the number of glaucoma medications. The complication rate was higher in eyes with ExG. Therefore, these eyes require more careful management after a KDB procedure.

Comparison of Different Procedures in a Combination of Ab Interno Microhook Trabeculotomy and Cataract Surgery

The purpose of this study was to compare the clinical outcomes of ab interno microhook trabeculotomy (µLOT) before and after cataract surgery for the combination of µLOT and cataract surgery. This retrospective case series included 40 eyes that underwent µLOT combined with cataract surgery at Kochi University Hospital. Groups 1 (20 eyes) and 2 (20 eyes) included eyes that underwent µLOT before and after cataract surgery, respectively. The patient characteristics and clinical outcomes were also analyzed. The mean preoperative intraocular pressure (IOP) in Groups 1 and 2 (26.1 ± 12.2 mmHg and 20.6 ± 8.8 mmHg) was reduced significantly to 14.1 ± 3.3 mmHg and 12.9 ± 3.2 mmHg, respectively, at 5–7 months postoperatively. The median preoperative number of antiglaucoma medications in Groups 1 and 2 (4.0 and 3.5) also decreased significantly, to 2.5 and 1.0, respectively, at 5–7 months postoperatively. Postoperative hyphema with niveau formation in Groups 1 and 2 was observed in one eye (5.0%) and six eyes (30.0%), respectively. For the combination of µLOT and cataract surgery, performing µLOT before cataract surgery may be less likely to result in postoperative hyphema with niveau formation.

A Review of Excisional Goniotomy Performed with the Kahook Dual Blade for Glaucoma Management

Aim

To review the published literature describing clinical outcomes of excisional goniotomy using the Kahook Dual Blade (KDB) for the management of glaucoma.

Background

A family of less invasive glaucoma procedures-including excisional goniotomy with the KDB-has been developed to provide moderate reductions in intraocular pressure and/or medication burden in eyes with therapeutic needs that may not warrant the risks associated with more traditional procedures such as trabeculectomy and tube-shunt implantation. This review's goal is to synthesize the existing literature into a compendium of excisional goniotomy's indications, technique, efficacy and safety outcomes, and optimal place in glaucoma management.

Review results

Excisional goniotomy with the KDB effectively lowers IOP and reduces the medication burden in eyes with POAG and other forms of glaucoma across the spectrum of both baseline IOP and disease severity. The procedure exhibits a safety profile that is on par with other angle-based surgical interventions and enhanced safety compared to filtration procedures. It can be performed by comprehensive ophthalmologists as well as glaucoma specialists. This procedure as a standalone operation delivers IOP reductions consistent with filtration surgery, and in combination with cataract surgery delivers both IOP and medication reductions at least as great as other minimally invasive procedures.

Conclusion

Given the broad base of evidence supporting its use in a wide variety of clinical scenarios, excisional goniotomy with the KDB can play a meaningful role in the achievement of patient-specific glaucoma therapy goals.

Clinical significance

These aggregate findings support the efficacy and safety of excisional goniotomy with the KDB and clarify the patient profiles best suited for this procedure.

How to cite this article

Dorairaj S, Radcliffe NM, Grover DS, et al. A Review of Excisional Goniotomy Performed with the Kahook Dual Blade for Glaucoma Management. J Curr Glaucoma Pract 2022;16(1):59-64.

Gonioscopy-assisted transluminal trabeculotomy versus goniotomy with Kahook dual blade in patients with uncontrolled juvenile open-angle glaucoma: a retrospective study

Background

To compare the efficacy and safety of gonioscopy-assisted transluminal trabeculotomy (GATT) and Kahook Dual Blade (KDB) excisional goniotomy in patients with uncontrolled juvenile open-angle glaucoma (JOAG).

Methods

Thirty-three patients (46 eyes) were included in this single-center, retrospective, comparative study and treated with GATT (36 eyes) or KDB goniotomy (13 eyes). Intraocular pressure (IOP), number of glaucoma medications, adverse events, and additional anti-glaucoma procedures were collected during pre- and postoperative visits. Surgical success was defined as 6 mmHg ≤ IOP ≤ 18 mmHg and ≥ 20% IOP reduction from baseline with (partial success) or without (complete success) IOP-lowering medications.

Results

The mean ± SD preoperative IOP was 30.48 ± 12.9 mmHg and 26.08 ± 13.1 mmHg (P = 0.164) on 3.71 ± 0.46 and 3.08 ± 0.86 (P = 0.023) glaucoma medications in GATT and KDB group, respectively. At 3 months, the mean ± SD IOP was 15.48 ± 5.93 mmHg and 20.0 ± 10.8 mmHg after GATT and KDB, respectively (P = 0.072). The percentage of IOP lowering from baseline was 44.4 in the GATT group and 14.1 in the KDB group (P = 0.011). The mean reduction in medications was 2.6 ± 1.7 and 0.8 ± 1.2 three months after GATT and KDB, respectively (P < 0.001). Cumulative proportion of partial and complete success were 65.6 and 44.7% in the GATT group, 30.8 and 15.4% in the KDB group at 6 months. Additional procedures were required in 13.9% of cases after GATT and in 61.5% after KDB (P = 0.001). Patients in the GATT group with prior anti-glaucoma procedures and postoperative IOP spikes were more likely to fail, while those with complete trabeculotomy had a better prognosis.

Conclusions

Reduction of IOP and medications were greater after GATT in uncontrolled JOAG eyes. Whereas, more additional IOP-lowering procedures were required after KDB goniotomy.

Trial registration

This study was registered under the Chinese Clinical Trial Registry (ChiCTR2000034172, 27/06/2020).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-02159-z.

Initial experience with phacoemulsification and goniotomy using the Kahook dual blade in advanced open-angle glaucoma: Six-month outcomes in Indian eyes

Purpose:

The aim of this study was to report our initial experience on the outcomes of phacoemulsification in combination with goniotomy using the Kahook Dual Blade (KDB) in eyes with advanced open-angle glaucoma (OAG).

Methods:

The outcomes of phaco-goniotomy with KDB in advanced OAG in Indian eyes were retrospectively analyzed. Based on the Hodapp-Anderson-Parrish criteria of visual field defects, severe glaucoma (mean deviation on standard automated perimetry worse than 12 dB) was considered as advance glaucoma. Preoperative, intraoperative, and postoperative data were collected through 6 months of follow-up. Outcome measures included antiglaucoma medications (AGM), the proportion of eyes achieving >1AGM reduction, intraocular pressure (IOP), and visual acuity.

Results:

Median (interquartile range) number of AGM in eyes that underwent phaco-KDB goniotomy reduced from 2 (2,3) at baseline to 1 (0,1) at 6 months (P = 0.002). Median IOP reduced from 20 (20,26) mmHg at baseline to 14 (12,15) mmHg at 6 months (P = 0.02). The proportion of eyes achieving >1 medication reduction was 88% eyes (8/9). Adverse events noted were IOP spike (22 mmHg) in 2 eyes and intra-op hyphema in 1 eye on postoperative day-1, both resolved in a week with conservative management. Except one eye with central corneal scar due to prior pterygium surgery, 8 eyes had 20/20 vision at 1 week which was maintained till last follow-up.

Conclusion:

Phacoemulsification with KDB Goniotomy significantly lowered the need for AGM with moderate IOP reduction in advanced OAG eyes. There were no serious complications and the visual recovery was good and early.

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.

12-month clinical outcomes of combined phacoemulsification and ab interno trabeculectomy for open-angle glaucoma in the United Kingdom

BACKGROUND/OBJECTIVES

To describe intraocular pressure (IOP) and ocular hypotensive medication outcomes of combined phacoemulsification and ab interno trabeculectomy with the Kahook Dual Blade (KDB; New World Medical, Inc, Rancho Cucamonga, CA) in adults with cataract and open-angle glaucoma (OAG).

SUBJECTS/METHODS

Retrospective chart review of existing medical records. Data collected included intraocular pressure (IOP) and IOP-lowering medication use preoperatively and through up to 24 months postoperatively. Paired t-tests were utilized to compare preoperative to postoperative mean IOP and mean medications used.

RESULTS

Data from 32 eyes of 26 subjects were analyzed. Subjects were predominantly Caucasian (25/26) had mean (standard error) age of 79.3 (1.2) years, and eyes had moderate-advanced OAG (mean visual field mean deviation -8.3 [1.3] dB). Mean IOP was 19.8 (0.8) mmHg at baseline and 15.5 (0.6) mmHg (p<0.0001) after mean follow-up of 11.5 (1.0) months; IOP reductions of ≥20% were achieved in 20/32 eyes (62.5%). Mean medication use declined from 2.4 (0.2) medications per eye at baseline to 0.5 (0.2) at last follow-up (p<0.0001); 23/32 eyes (71.9%) were medication-free at last follow-up. No vision-threatening complications were observed.

CONCLUSIONS

Combined phacoemulsification and ab interno trabeculectomy with the KDB safely provided mean IOP reductions of 21.7% and mean IOP medication reductions of 83% after mean follow-up of 12 months in eyes with moderate to advanced OAG. This procedure provides medication-independence in most eyes with statistically and clinically significant IOP reductions.

Long term outcome of combined phacoemulsification and excisional goniotomy with the Kahook Dual Blade in different subtypes of glaucoma

To characterize changes in intraocular pressure (IOP) and IOP-lowering medications through up to 2 years of follow-up in patients undergoing combined phacoemulsification and excisional goniotomy with the Kahook Dual Blade (phaco-KDB), with simultaneous goniosynechialysis in cases of angle-closure glaucoma. Prospective, non-comparative, interventional case series. Consecutive patients with medically-treated glaucoma and visually-significant cataract underwent combined surgery. Analysis was conducted on open-angle (OAG) and angle-closure (ACG) glaucoma groups separately. Thirty-seven patients with OAG (24 with primary OAG and 13 with pseudoexfoliation glaucoma) and 11 with ACG were enrolled. In OAG eyes, mean (standard error) baseline IOP was 21.1 (0.9) mmHg and through 24 months of follow-up was reduced by 6.4-7.7 mmHg (24.6-32.1%; p ≤ 0.0001 at all time points). In ACG eyes, mean baseline IOP was 20.8 (1.6) mmHg and was reduced by 6.1-8.77 mmHg (23.4-39.0%; p ≤ 0.0353). Mean medications were reduced by 61.9-89.1% (p ≤ 0.0001) in OAG eyes and by 56.3-87.3% (p ≤ 0.0004) in ACG eyes. Phaco-KDB significantly lowered IOP ~ 30% and medications by > 50% through 24 months. This combined procedure provides meaningful long-term reductions in IOP and need for IOP-lowering medication and does not adversely affect visual rehabilitation in eyes with cataract and glaucoma.

Twelve-month results of ab interno trabeculectomy with Kahook Dual Blade: an interventional, randomized, controlled clinical study

PURPOSE

To evaluate the efficacy and safety profile of Kahook Dual Blade ab interno trabeculectomy combined with phacoemulsification compared to stand-alone conventional cataract surgery.

METHODS

A single-center longitudinal, randomized controlled trial was conducted. Patients older than 18 years with coexisting cataract and open-angle glaucoma or ocular hypertension were invited to participate. Preoperative and postoperative clinical data were collected and analyzed preoperatively and at months 1, 3, 6, and 12 after the procedure. Main outcome measures included best corrected visual acuity, intraocular pressure, number of glaucoma medications, endothelial cell count, and standard automated perimetry.

RESULTS

Forty-two eyes from 33 patients were randomly allocated to the combined cataract and KDB (treatment, n = 21) or cataract alone (control, n = 21) groups. Intraocular pressure decreased from 17.9 ± 3.5 to 16.0 ± 2.2 mmHg and from 17.3 ± 2.5 to 15 ± 3.2 mmHg at the last visit in the treatment and control groups (p = 0.47). The use of glaucoma medications was reduced from a median (IQR) 1 (1-2) to 0 (0-0) in the treatment group and from 1 (1-2) to 0 (0-1) in the control group, with no significant differences between groups at the 12-month visit (p = 0.47). Best corrected visual acuity, endothelial cell count, and standard automated perimetry remained similar during follow-up in both groups.

CONCLUSIONS

In patients with well-controlled, mild-to-moderate glaucoma, adding ab interno trabeculectomy with KDB to phacoemulsification might not be more effective than phacoemulsification alone to reach mid-teens IOP values. Both procedures showed similar safety profiles.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04202562, December 17, 2019 retrospectively registered.

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

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

Outcomes of phacoemulsification and endoscopic cyclophotocoagulation performed with dual blade ab interno trabeculectomy or trabecular micro-bypass stent insertion

BACKGROUND/OBJECTIVE

To report the initial outcomes of phacoemulsification, endoscopic cyclophotocoagulation, and dual blade ab interno trabeculectomy (PEcK), and compare them to those of phacoemulsification, endoscopic cyclophotocoagulation, and trabecular micro-bypass stent insertion (ICE-1).

SUBJECTS/METHODS

Patients from January 2018 to December 2019 that underwent PEcK or ICE-1 at a tertiary referral centre were included in this retrospective comparative case series. Patients were excluded if they had additional concomitant procedures, less than 6 weeks (42 days) of follow-up or were not at least 18 years old. Intraocular pressure (IOP), number of glaucoma medications, and best-corrected visual acuity were collected preoperatively and postoperatively at 6 weeks, 3, 6, and 12 months. Kaplan-Meier survival analysis and Cox proportional-hazards regression were conducted to elucidate any factors associated with survival time.

RESULTS

The mean preoperative IOP was 18.3 ± 5.9 mmHg in the PEcK group (53 eyes) and 14.7 ± 4.3 mmHg in the ICE-1 group (23 eyes) (p = 0.004) on 3.3 ± 1.3 and 1.7 ± 0.93 glaucoma medications (p < 0.001), respectively. Twelve months postoperatively the mean IOP reduction was 5.1 ± 4.4 mmHg and 2.3 ± 4.0 mmHg (p = 0.08), and the mean medication reduction was 1.6 ± 1.5 and 0.97 ± 0.66 (p = 0.10), in the PEcK and ICE-1 groups, respectively. Kaplan-Meier survival analysis did not reveal any differences in treatment survival.

CONCLUSIONS

Both PEcK and ICE-1 provide clinically relevant reductions in IOP and glaucoma medication burden, however the PEcK procedure may confer greater reductions in IOP. The procedures did not differ with regard to Kaplan-Meier survival probability.

Twelve-month surgical outcome and prognostic factors of stand-alone ab interno trabeculotomy in Japanese patients with open-angle glaucoma

The purpose of the study was to evaluate the 12-month surgical outcome and prognostic factors of stand-alone ab interno trabeculotomy. The changes in the intraocular pressure (IOP) and medication score and the success rate of the surgery were analyzed. Thirty-four eyes of 29 patients with primary open-angle glaucoma (POAG; n = 16) or pseudoexfoliation glaucoma (PEG; n = 18) with a 12-month follow-up period were included in the study. The decreases in IOP and medication score from the baseline to the all-time-point were statistically significant (P < 0.001). The surgical success rates were 97.1%, 76.5%, and 44.0% at 3 months (90 days), 6 months (180 days), and 12 months (365 days), respectively. A mixed effect Cox model revealed that the type of glaucoma (POAG) was significantly associated with surgical failure (P = 0.044). Furthermore, the surgical success rate was significantly higher in eyes with PEG than it was in those with POAG (P = 0.019). Stand-alone ab interno trabeculotomy significantly lowered both the IOP and the medication score in patients with glaucoma, although almost one quarter of the cases needed additional glaucoma surgeries. The surgical success rate was significantly higher in eyes with PEG than it was in those with POAG.

Excisional Goniotomy in Latino Patients with Open-Angle Glaucoma: Outcomes Through 24 Months

Purpose

To characterize the efficacy of combined phacoemulsification and excisional goniotomy with the Kahook Dual Blade (KDB-phaco) in eyes of Latino adults with cataract and open-angle glaucoma (OAG).

Methods

Health records of consecutive Latino patients undergoing KDB-phaco were retrospectively reviewed. Intraocular pressure (IOP) and IOP-lowering medication use were recorded at baseline and each postoperative visit through up to 24 months. Primary outcomes were reductions in IOP and medication use from baseline; secondary outcomes were the proportions of eyes achieving IOP reductions of ≥20% and medication reductions ≥1 medication from baseline. Subgroup analysis was conducted in eyes with high and low baseline IOP.

Results

Data from 44 eyes of 32 Latino patients with OAG were analyzed. Mean IOP was 17.8 (0.7) mmHg at baseline and postoperatively ranged from 12.4 to 13.8 mmHg (p≥0.0003), representing mean IOP reductions of 4.2–4.6 mmHg (19.7–23.1%). Mean medication was 1.5 (0.2) medications per eye at baseline and postoperatively ranged from 0.2 to 1.0 (p≥0.0061), representing mean medication reductions of 0.7–1.2 medications per eye (47.1–87.2%). In the low baseline IOP group (<18 mmHg), mean IOP was significantly reduced through Month 24 and medications through Month 12; in the high baseline IOP group (≥18 mmHg), IOP and medications were significantly reduced through Month 24. From Months 1–24, IOP reductions of ≥20% were achieved by 48.4–56.2% of eyes in the full cohort, by 20.0–33.3% in the low IOP group, and by 66.7–100% in the high IOP group; medication reductions of ≥1 medication were achieved by 72.0–95.6%, 64.7–94.2%, and 87.5–100% of eyes, respectively.

Conclusion

Combined KDB-phaco in eyes of Latino patients with glaucoma and cataract significantly lowers IOP and the need for IOP-lowering medications for up to 24 months and should be considered for such patients who warrant IOP reduction, medication reduction, or both.

Comparison of 12-Month Outcomes of Kahook Dual Blade Excisional Goniotomy Performed by Attending versus Resident Surgeons

Objective Kahook Dual Blade goniotomy (KDB) has proven effective in lowering intraocular pressure (IOP) and reducing the medication burden in patients with glaucoma. This study compares outcomes up to 12 months postoperatively after KDB combined with phacoemulsification (phaco-KDB) between an ophthalmology attending and residents.

Methods A retrospective analysis was performed on 160 eyes of 113 patients who received a phaco-KDB performed by either an ophthalmology attending or a resident under direct guidance of the attending. Data for each patient was collected preoperatively and at 1 day, 1 week, 1 month, 3 months, 6 months, and 12 months postoperatively. The primary outcome measure was surgical success, defined as 20% IOP reduction or at least 1 medication reduction at 12 months. The secondary outcome measures included mean IOP and medication reduction at each postoperative time point, adverse events, operating time, and survival time, defined as time to failure to meet the criteria for surgical success or requiring a secondary IOP-lowering procedure.

Results Preoperative mean IOP was comparable between the two groups (p = 0.585), while baseline medications were higher in the attending group (p = 0.040). Rate of successful outcomes was similar in both groups at 12 months (73.3% attending vs. 87.5% residents, p = 0.708). Mean IOP reduction (1.7 vs. 4.3%, p = 0.278) and medication reduction (0.7 vs. 0.6, p = 0.537) also did not differ at 12 months. Presence of adverse events was similar between the groups (21.6 vs. 27.3%, p = 0.938). The survival time was significantly longer in the attending group (356.3 ± 20.2 days vs. 247.1 ± 26.8 days, p = 0.003). Resident cases took ∼10 minutes longer compared with attending cases (p < 0.001).

Conclusion IOP lowering outcomes and rate of adverse events of KDB were similar whether the primary surgeon was an attending or a resident surgeon. The survival time was significantly longer in the attending group, but overall success rate was 77.5% for both groups. This suggests phaco-KDB is an effective procedure that can be safely performed by a trainee under direct supervision of an experienced surgeon.

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.

Predictive Factors for Outcomes of Selective Laser Trabeculoplasty

We sought to  determine predictive factors for selective laser trabeculoplasty (SLT) outcome. 252 eyes from 198 adult patients with open-angle glaucoma who underwent SLT between July 2016 and February 2018 with a minimum 6 month follow up were reviewed. We defined success as ≥20% IOP reduction or ≥1 medication reduction without an IOP lowering procedure. We also evaluated the relationship of these factors to postoperative IOP elevation >5 mmHg (IOP spikes). Our primary outcome measure was association between age, type and severity of glaucoma, pigmentation of the trabecular meshwork (PTM), total energy delivered, and baseline intraocular pressure (IOP) with success. At 2 and 6 months, 33.6% (76/226) and 38.5% (97/252) of eyes met success criteria respectively. Baseline IOP > 18 mmHg was significantly associated with success both at 2 and 6 months, reducing IOP by 5.4 ± 5.3 mmHg (23.7% reduction), whereas those with lower baseline remained at −0.7 ± 4.6 mmHg (4.9% increase) at 6 months (P < 0.001). No other baseline characteristics significantly predicted success or IOP spikes. Patients with higher baseline IOPs had greater success rates and mean IOP reduction at both 2 and 6 months following SLT. Age, type and severity of glaucoma, PTM, or total energy delivery had no association with procedural success or IOP spikes. Patients with higher baseline IOP may experience greater lowering of IOP after SLT. However, SLT may be equally successful for patients with a variety of other characteristics.

An Update on Microinvasive Glaucoma Surgery Concurrent With Cataract Extraction

Purpose of Review

In this article, we review the current options for microinvasive glaucoma surgery (MIGS) combined with cataract extraction in the USA and the efficacy of the various approaches.

Recent Findings

MIGS is a rapidly growing area of research and clinical interest. Available surgeries aim to reduce intraocular pressure by improving aqueous outflow through the trabecular or subconjunctival pathways or by reducing aqueous production.

Summary

Multiple approaches to MIGS are utilized in clinical practice. On average, these surgeries are safe and modestly effective in reducing intraocular pressure. Future research will demonstrate which surgical approaches are most efficacious, whether and how to combine MIGS, and the role of MIGS in improving patient quality of life.

Comparison Of Surgical Outcomes Of 360° Circumferential Trabeculotomy Versus Sectoral Excisional Goniotomy With The Kahook Dual Blade At 6 Months

Purpose

To compare reductions in intraocular pressure (IOP) and IOP-lowering medication use following sectoral excisional goniotomy with the Kahook Dual Blade (KDB) or 360° trabeculotomy (via either Trab360 or gonioscopy-assisted transluminal trabeculotomy [GATT]) in eyes with open-angle glaucoma (OAG) undergoing phacoemulsification cataract surgery.

Methods

A retrospective review was conducted to collect data from adult subjects with early to advanced primary or secondary OAG undergoing phacoemulsification combined with either KDB or 360° trabeculotomy (Trab360 or GATT) between August 1, 2016 and July 30, 2018 for which 6-month follow-up was available. Data collected included IOP, glaucoma medications, adverse events, and additional IOP-lowering procedures. The primary outcome measure was surgical success (≥20% IOP or ≥1 medication reduction without additional IOP-lowering procedures) at 6 months.

Results

Data were collected from 74 eyes of 61 subjects undergoing KDB excisional goniotomy and 27 eyes of 25 subjects undergoing 360° trabeculotomy (19 eyes of 17 subjects undergoing Trab360 and 8 eyes of 8 subjects undergoing GATT). At 6 months, 81.7% (58/71) of KDB eyes and 84.6% (22/26) of 360° trabeculotomy eyes achieved surgical successes (P=0.737). Mean IOP reductions and medication reductions were similar between groups at 6 months. However, more eyes undergoing KDB than Trab360/GATT achieved target IOP ≤18 mmHg (80.0% [56/70] vs 59.3% [16/27], P=0.040) and ≤15 mmHg (61.4% [43/70] vs 25.9% [7/27], P=0.003) without further IOP-lowering interventions at 6 months. The nature and frequency of adverse events were similar between groups.

Conclusions

Both KDB and Trab360 or GATT procedures similarly lowered both IOP and the need for IOP-lowering medications during the first 6 postoperative months. More eyes undergoing KDB excisional goniotomy than 360° trabeculotomy attained target IOP ≤18 mmHg and ≤15 mmHg at 6 months. A full 360° trabecular bypass may not be necessary to achieve maximal efficacy from this class of micro-invasive glaucoma procedures.