Intraocular pressure 3 to 4 hours and 20 hours after cataract surgery with and without ab interno trabeculectomy

Long-term outcomes of combined phacotrabeculectomy surgery in a Singapore tertiary hospital

PURPOSE

To describe the long-term outcomes of phacotrabeculectomy from a tertiary glaucoma service in Singapore.

DESIGN

Retrospective case series.

METHODS

Seven hundred ninety-six eyes of 698 patients who underwent phacotrabeculectomy surgery at the Singapore National Eye Centre between 2005 and 2007 with a minimum follow-up of three years were included. The primary outcome measure was intraocular pressure (IOP). Secondary outcomes included best-corrected visual acuity (BCVA), number of glaucoma medications, and surgical complications.

RESULTS

The mean age was 69.5 years, 51 % were male, and 86 % were Chinese. Most eyes had primary glaucoma (90.6 %). The mean follow-up duration was 9.4 years. The overall success rate at three years was 97 % if surgical success was defined as IOP ≤ 21 mm Hg, 92 % if IOP ≤ 18 mm Hg, 66 % if IOP ≤ 15 mm Hg. By Kaplan-Meier survival analysis over 13 years, the cumulative success rate fell from 98.1 % to 89.1 % if IOP ≤ 21 mm Hg, 98.1-76.9 % if IOP ≤ 18 mm Hg, 98-50.3 % if IOP ≤ 15 mm Hg. The postoperative IOP improved significantly at all time points (P < 0.05) and 72 % had at least 20 % IOP reduction. There was a slight improvement in postoperative BCVA (P < 0.05). The mean number of glaucoma medications was reduced postoperatively (P < 0.001). There were no significant risk factors for surgical failure.

CONCLUSIONS

Phacotrabeculectomy was found to be safe, resulting in clinically significant IOP lowering for 13 years with reduced dependency on glaucoma medications and improved BCVA.

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.

Ab Interno Goniotomy with the Kahook Dual Blade in a Monocular Patient with Mucous Membrane Pemphigoid and Refractory Open Angle Glaucoma: A Case Report

Purpose

To describe the case of a monocular patient with ocular mucous membrane pemphigoid (MMP) and open angle glaucoma refractory to medical treatment, who was successfully managed with ab interno goniotomy at the time of cataract surgery.

Methods

A 63-year-old woman with a history of severe MMP presented with exacerbation of the disease in both eyes. Vision was 20/80 in the right eye and light perception in the left eye. Symblepharon formation, trichiasis and forniceal foreshortening were present in the right eye, while the cornea of the left eye was completely conjunctivalized. Following aggressive systemic immunosuppressive therapy with corticosteroids and cyclophosphamide, the disease was brought under control. However, the patient developed a mature cataract and high intraocular pressure (IOP) of 28 mmHg on maximal medical therapy. Due to the high risk of ocular MMP exacerbation with glaucoma filtration surgery, the decision was made to proceed with cataract extraction combined with ab interno goniotomy with the Kahook Dual Blade.

Results

There were no intraoperative complications. The IOP has remained in the 12–14 mmHg range without any topical glaucoma medications over a total follow up of 3.5 years.

Conclusion

Ab interno goniotomy using the Kahook Dual Blade can significantly reduce IOP and medication burden in MMP cases, where any type of conjunctival incisional surgery could induce disease flare up. In this case, it represented a safe and effective surgical procedure for ocular MMP with concomitant refractory open angle glaucoma.

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.

Intraocular Pressure After Cataract Surgery Combined With Ab Interno Trabeculectomy Versus Trabecular Micro-bypass Stent: An Intrasubject Same-surgeon Comparison

PRECIS

Combining Trabectome or iStent with phacoemulsification equally reduces intraocular pressure (IOP) and IOP-lowering medication burden during a 24-month follow-up, with a possible advantage to the Trabectome in the early postoperative period.

PURPOSE

Intrasubject same-surgeon comparison between phacoemulsification combined with Trabectome (Phaco/Trabectome) versus one first-generation iStent (Phaco/iStent).

SETTINGS

Private glaucoma and cataract practice.

DESIGN

This is a retrospective interventional case series.

METHODS

Data collected at 3 to 4 and 20 to 24 hours and up to 30 months following Phaco/Trabectome in 1 eye and Phaco/iStent in the contralateral eye in patients with bilateral visually-significant cataract and open-angle glaucoma. Evaluations included IOP, intraocular pressure-lowering medications (IOPmeds), visual acuity, and complications.

RESULTS

Forty-five patients (90 eyes) were identified (age 76.5, 57 to 95 y). At 3 to 4 hours, IOP was above baseline in 12 and 13 eyes following Phaco/Trabectome and Phaco/iStent, respectively, but the degree of IOP elevation was smaller (P=0.048) following Phaco/Trabectome: 4.3 mm Hg, 2.0 to 6.6 mm Hg (95% confidence interval) versus Phaco/iStent: 8.7 mm Hg, 3.8 to 13.6 mm Hg. At 20 to 24 hours, compared with baseline, IOP was significantly lower after Phaco/Trabectome (P=0.004) but not after Phaco/iStent (P=0.14) although the rate of hyphema was higher following Phaco/Trabectome (12/45 vs. 2/45 eyes, P=0.007). IOP reduction from baseline at 3 to 4 hours was significantly larger (P=0.020) in the 21 eyes with hyphema: -3.9, -6.4 to -1.4 versus the 69 eyes without hyphema: -0.3, -2.0 to +1.4. At 1, 6, 12, and 24 months, IOP and number of IOPmeds were similar and significantly lower compared with baseline following either procedure. No complications were encountered in either group.

CONCLUSIONS

Combined phacoemulsification with either Trabectome or first-generation iStent similarly lowers IOP and IOPmeds burden at 1, 6, 12, and 24 months following surgery. The Trabectome may have an advantage in lowering IOP faster and lessening the degree of IOP elevations in the early postoperative period.

Combined Phacoemulsification and 360-Degree Endocyclophotocoagulation with and without a Kahook Dual Blade in Patients with Primary Open-Angle Glaucoma

Purpose

The present study aimed to compare the outcomes of combined phacoemulsification and 360-degree endocyclophotocoagulation with and without goniotomy using a Kahook Dual Blade in patients with glaucoma.

Patients and Methods

We enrolled 37 patients, 21 of whom underwent combined phacoemulsification with 360-degree endocyclophotocoagulation and goniotomy using a Kahook Dual Blade (tri-modal therapy (T-MT) group). The remaining 16 patients underwent phacoemulsification with endocyclophotocoagulation (bi-modal therapy (B-MT) group). Visual acuity, intraocular pressure, and number of glaucoma medications were recorded before the study and postoperatively on the first day, at week 1, and at 1, 3, 6, 9, and 12 months. Surgical success was defined as an IOP ≤12 mmHg and ≥6 mmHg or an at least 20% reduction in IOP from baseline with (qualified success) or without medications (complete success).

Results

Forty-nine eyes were included. Baseline mean IOP was 16.96±3.66 mmHg and 15.64±4.88 mmHg in the T-MT and B-MT groups (p=0.122), respectively. At the 12-month follow-up, mean IOP values were 11.44±2.15 mmHg and 12.45±1.90 mmHg (p=0.031) in the T-MT and B-MT groups, respectively. Complete success rates were 37% in the T-MT group and 31% in the B-MT group, while qualified success rates were 74% and 50%, respectively. Glaucoma medications decreased from 2.0±1.4 to 0.8±1.0 (p<0.001) in the T-MT group and from 1.5±1.3 to 1.0±1.5 in the B-MT group (p=0.032). Similar improvements in visual acuity were observed in both groups. Complications were mild and resolved without intervention.

Conclusion

The tri-modal treatment is safe and may be more effective in reducing IOP and glaucoma medication requirements than bi-modal treatment.

Combining Baerveldt Implant with Trabectome Negates Tube Fenestration: A Coarsened-matched Comparison

Purpose

To assess the efficacy and survival rate of the Trabectome-mediated ab interno trabeculectomy combined with non-fenestrated Baerveldt glaucoma implant compared with the Baerveldt glaucoma implant alone.

Methods

In this retrospective comparative case series, 175 eyes undergoing primary glaucoma surgery (Baerveldt–Trabectome [BT] group: 60 eyes and Baerveldt [B] group: 115 eyes) were included. Participants were identified using the procedural terminology codes. Groups were then matched by Coarsened Exact Matching that resulted in the inclusion of 51 eyes in each group. The primary outcome measure was surgical success defined as 5 mmHg < intraocular pressure (IOP) ≤ 21 mmHg, and IOP reduction ≥ 20% from baseline, and no need to reoperation for glaucoma. Secondary outcome measures were IOP, number of glaucoma medications, and best-corrected visual acuity (BCVA).

Results

The cumulative probability of success at one year was 61% in the BT group and 50% in the B group. IOP decreased from 23.5 ± 2.4 mmHg at baseline to 14.1 ± 2.7 mmHg at the final follow-up in the BT group (P = 0.001). The corresponding values for the B group were 23.2 ± 2.0 mmHg and 13.9 ± 1.6 mmHg, respectively (P = 0.001). There was no significant difference between the groups in terms of IOP at the final follow-up (P = 0.56). The number of medications at baseline was 2.3 ± 0.3 in both groups. However, the BT group needed fewer drops at all postoperative time intervals and used 1.1 ± 0.3 versus 2.0 ± 0.4 eye drops (group B) at the final follow-up visit (P = 0.004). Eyes in B with phacoemulsification had a significantly higher IOP on day 1 compared to B (23.2 ± 14.3 versus 17.9 ± 11.4, P = 0.041). During the one-year follow-up, 7 (13.7%) patients in BT group and 18 (35.2%) in B group experienced hypotony (P = 0.04). No dangerous hypotony or hypertension occurred in BT group. The mean BCVA at baseline was 0.64 ± 0.85 logMAR and changed to 0.55 ± 0.75 logMAR in BT and B groups, respectively (P = 0.663). The corresponding numbers for the final follow-up visit was 0.72 ± 1.07 and 0.63 ± 0.97 logMAR, respectively (P = 0.668).

Conclusion

We observed similar rates of success and IOP reduction using BT and B techniques. BT group needed fewer glaucoma medications. Tube fenestration was unnecessary in BT group resulting in less postoperative ocular hypotony and hypertension. The results of our study indicate that additional trabectome procedure makes Baerveldt glaucoma implant safer, easier to handle, and more predictable in the most vulnerable patients with advanced glaucoma.

Effect of a Schlemm's Canal Microstent on Early Postoperative Intraocular Pressure after Cataract Surgery: An Analysis of the HORIZON Randomized Controlled Trial

PURPOSE

To compare early postoperative intraocular pressure (IOP) in patients who underwent cataract surgery alone with those who underwent cataract surgery combined with implantation of a Hydrus Microstent (HMS) (Ivantis, Irvine, CA).

DESIGN

Subanalysis of data from the randomized controlled HORIZON trial, a multicenter trial including 26 US and 12 international sites.

PARTICIPANTS

Participants with mild/moderate primary open-angle glaucoma (POAG) and visually significant cataract with mean modified diurnal IOP between 22 and 34 mmHg after washout of IOP-lowering medications.

METHODS

A total of 556 subjects were randomized in a 2:1 ratio to undergo cataract surgery with placement of the HMS versus cataract surgery alone (no microstent [NMS]). All eyes were washed out of IOP-lowering medications before surgery and remained unmedicated until surgery. No IOP-lowering prophylaxis was used postoperatively. Comprehensive eye examination including measurement of intraocular pressure was conducted on postoperative day (POD) 1, week 1, and month 1.

MAIN OUTCOME MEASURES

Postoperative IOP >40 mmHg was analyzed as the primary outcome. Incidence of IOP increase >10 mmHg above baseline, unmedicated IOP, and mean IOP were analyzed as secondary outcomes.

RESULTS

A total of 369 eyes were randomized to the HMS group, and 187 eyes were randomized to cataract surgery alone. The HMS and NMS groups did not differ with respect to baseline demographic or ocular characteristics. On POD1, the incidence of IOP spike >40 mmHg was significantly higher at 14.4% in the NMS group compared with 1.4% in the HMS group (P < 0.001). The incidence of IOP increase ≥10 mmHg relative to baseline on POD1 was also significantly higher in the NMS group than in the HMS group (22.5% vs. 3.0%, P < 0.001). IOP in the NMS group was significantly higher than in the HMS group (27.6 vs. 17.0 mmHg, P < 0.001). In multivariable logistic regression analysis, higher baseline IOP predicted higher odds of POD1 IOP spike >40 mmHg, whereas the presence of HMS was associated with a lower likelihood of postoperative IOP spike.

CONCLUSIONS

The addition of an HMS at the time of cataract surgery lowered the risk of markedly elevated IOP in the early postoperative period in patients with glaucoma.

Stratification of phaco-trabectome surgery results using a glaucoma severity index in a retrospective analysis

Background

To stratify the outcomes of phacoemulsification combined with trabectome surgery using a new glaucoma severity index.

Methods

This is a retrospective, observational cohort study that included open angle glaucoma patients with visually significant cataract that had phacoemulsification combined with trabectome surgery. Exclusion criteria were follow-up less than 12 months, any other surgeries or diagnosis of neovascular or active uveitic glaucoma. Patients were stratified into four groups according to the Glaucoma Index (GI) that incorporated preoperative intraocular pressure (IOP), number of medications and visual field status. The primary outcome measures were IOP reduction and the success rate at 12 months. We examined the relationship between GI group and IOP and medications at one year with a linear regression analysis and survival with log-rank testing.

Results

Of 1374 patients, a total of 498 cases with 12 month follow-up were included in the study after applying the exclusion criteria. At one year, IOP of GI groups 1 through 4 was reduced by 2.9 ± 4.4, 3.6 ± 5.0, 3.9 ± 5.3, and 9.2 ± 7.6 mmHg for. Individuals in the next higher GI group had a 1.69 ± 0.2 mmHg larger IOP decrease. The success rate was 98%, 93%, 96% and 88% at one year for GI groups 1 to 4 (p < 0.05).

Conclusions

A substantial IOP reduction was seen in subjects with more advanced glaucoma suggesting that the trabecular meshwork is the primary impediment to outflow and its ablation benefits those eyes relatively more than in mild glaucoma. A larger IOP reduction can be expected in individuals with a higher GI group that indicates a clinically more challenging glaucoma.

Ab interno trabeculectomy: patient selection and perspectives

Ab interno trabeculectomy is one among several recently introduced minimally invasive glaucoma surgeries that avoid a conjunctival incision and full-thickness sclerostomy involved in traditional glaucoma surgery. Ablation of the trabecular meshwork and inner wall of Schlemm's canal is performed in an arcuate fashion via a clear corneal incision, alone or in combination with phacoemulsification cataract surgery. Intraocular pressure reduction following ab interno trabeculectomy is limited by resistance in distal outflow pathways and generally stabilizes in the mid-to-high teens. Relief of medication burden has been demonstrated by some studies. A very low rate of complications, most commonly transient hyphema and intraocular pressure elevations in the immediate postoperative period, have been reported. However, available data are derived from small retrospective and prospective case series. Randomized, controlled trials are needed to better elucidate the potential merits of ab interno trabeculectomy in the combined setting versus phacoemulsification cataract surgery alone and to compare it with other minimally invasive glaucoma surgeries.

Combined phacoemulsification and trabectome for treatment of glaucoma

Ab interno trabeculectomy with the trabectome is a microincisional glaucoma surgery modality with an electrosurgical device to ablate the trabecular meshwork and inner wall of Schlemm canal to restore conventional outflow along its physiological route, thereby decreasing intraocular pressure. The device was approved by the FDA in 2004 and has since gained widespread use. Trabectome can be performed on its own or combined with cataract surgery for the treatment of ocular hypertension or advanced glaucoma with similar intraocular pressure reduction. It can be used after failed classical glaucoma surgeries and in narrow angles. Postoperative average intraocular pressure is independent of preoperative pressure and can be expected to be near 15 mm Hg with a theoretical minimum close to episcleral venous pressure. In combination with tube shunts, low intraocular pressures can be achieved during the hypertensive phase and long term. Although early postoperative hyphema is common, complications are rare and similar to those seen in cataract surgery, resulting in a safety profile that is favorable compared to older glaucoma surgeries. Aqueous angiography that is under development will allow anatomically targeted ablation.

Glaucoma Surgery Calculator: Limited Additive Effect of Phacoemulsification on Intraocular Pressure in Ab Interno Trabeculectomy

Purpose

To compare intraocular pressure (IOP) reduction and to develop a predictive surgery calculator based on the results between trabectome-mediated ab interno trabeculectomy in pseudophakic patients versus phacoemulsification combined with trabectome-mediated ab interno trabeculectomy in phakic patients.

Methods

This observational surgical cohort study analyzed pseudophakic patients who received trabectome-mediated ab interno trabeculectomy (AIT) or phacoemulsification combined with AIT (phaco-AIT). Follow up for less than 12 months or neovascular glaucoma led to exclusion. Missing data was imputed by generating 5 similar but non-identical datasets. Groups were matched using Coarsened Exact Matching based on age, gender, type of glaucoma, race, preoperative number of glaucoma medications and baseline intraocular pressure (IOP). Linear regression was used to examine the outcome measures consisting of IOP and medications.

Results

Of 949 cases, 587 were included consisting of 235 AIT and 352 phaco-AIT. Baseline IOP between groups was statistically significant (p≤0.01) in linear regression models and was minimized after Coarsened Exact Matching. An increment of 1 mmHg in baseline IOP was associated with a 0.73±0.03 mmHg IOP reduction. Phaco-AIT had an IOP reduction that was only 0.73±0.32 mmHg greater than that of AIT. The resulting calculator to determine IOP reduction consisted of the formula -13.54+0.73 × (phacoemulsification yes:1, no:0) + 0.73 × (baseline IOP) + 0.59 × (secondary open angle glaucoma yes:1, no:0) + 0.03 × (age) + 0.09 × (medications).

Conclusions

This predictive calculator for minimally invasive glaucoma surgery can assist clinical decision making. Only a small additional IOP reduction was observed when phacoemulsification was added to AIT. Patients with a higher baseline IOP had a greater IOP reduction.

Coarsened Exact Matching of Phaco-Trabectome to Trabectome in Phakic Patients: Lack of Additional Pressure Reduction from Phacoemulsification

Purpose

To compare intraocular pressure (IOP) after trabectome-mediated ab interno trabeculectomy surgery in phakic patients (T) and trabectome with same session phacoemulsification (PT) using Coarsened Exact Matching. Although phacoemulsification is associated with IOP reduction when performed on its own, it is not known how much it contributes in PT.

Methods

Subjects were divided into phakic T and PT. Exclusion criteria were follow-up for <12 months and additional glaucoma surgery. Demographics were compared by the Mann-Whitney U test and chi-squared test for continuous and categorical variables, respectively. Multiple imputation was utilized to avoid eliminating data with missing values. Groups were then matched using Coarsened Exact Matching based on age, race, type of glaucoma, baseline IOP, and number of preoperative glaucoma medications. Univariate linear regression was used to examine IOP reduction after surgery; those variables that were statistically significant were included in the final multivariate regression model.

Results

A total of 753 cases were included (T: 255, PT: 498). When all variables except for age were kept constant, there was an additional IOP reduction of 0.05±0.01 mmHg conferred for every yearly increment in age. Every 1 mmHg increase in baseline IOP correlated to an additional IOP reduction of 0.80±0.02 mmHg. Phacoemulsification was not found to be a statistically significant contributor to IOP when comparing T and PT (p≥0.05). T had a 21% IOP reduction to 15.9±3.5 mmHg (p<0.01) while PT had an 18% reduction to 15.5±3.6 mmHg (p<0.01). Number of medications decreased (p<0.01) in both groups from 2.4±1.2 to 1.9±1.3 and from 2.3±1.1 to 1.7±1.3, respectively.

Conclusion

Phacoemulsification does not make a significant contribution to postoperative IOP or number of medications when combined with trabectome surgery in phakic patients.