A deep dive into hyperbaric environments and intraocular pressure-a systematic review.

Purpose: SCUBA diving exposes participants to a unique hyperbaric environment, but few studies have examined the effects of such an environment on intraocular pressure (IOP) and glaucoma. This systematic review aims to consolidate recent literature findings regarding the impact of increased atmospheric pressure on IOP and glaucoma. Methods: Three online databases were searched to identify publications encompassing the subjects of diving or increased atmospheric pressure in conjunction with IOP or glaucoma. Three reviewers independently screened the publications and identified eligible articles. Relevant data was extracted from each article. The heterogeneity of the data precluded the conduct of a meta-analysis. Results: Nine studies met the inclusion criteria. Six experimental studies employed hyperbaric chambers to measure IOP under simulated diving conditions. Among these, IOP exhibited a reduction with increased atmospheric pressures in four studies, while the findings of two studies were inconclusive. One study measured IOP pre- and post-dive and another measured IOP with and without a diving mask. Post-dive, a decrease in IOP was observed, and a statistically significant reduction was noted when subjects wore a diving mask. A retrospective study examining the incidence of acute angle closure glaucoma attack found no association with weather or atmospheric pressure. Conclusion: The majority of studies found IOP to decrease with increased atmospheric pressure and after diving. The mechanisms underlying this reduction remain incompletely understood, with potential contributors including changes in ocular blood flow, sympathetic responses, and increased oxygenation. Hyperbaric chambers may have potential in future glaucoma treatments, but more studies are required to draw reliable conclusions regarding the safety of diving for glaucoma patients.

Surgical outcomes of excisional goniotomy using the kahook dual blade in severe and refractory glaucoma: 12-month results.

OBJECTIVES: To describe the efficacy and safety of goniotomy with trabecular meshwork excision using the Kahook Dual Blade (KDB, New World Medical Inc., Rancho Cucamonga, CA) in patients with severe or refractory glaucoma. METHODS: This retrospective multicentre case series reports on 40 eyes with severe or refractory open-angle glaucoma that underwent standalone or combined KDB goniotomy and were followed for 12 months post-operatively in the United-States, Mexico and Switzerland. Surgical success was defined as an intraocular pressure (IOP) reduction ≥20% from baseline at 12 months, with fewer medications than preoperatively. Mean IOP and antiglaucoma medication reduction, probabilities of achieving an IOP ≤16 or 18 mmHg, and adverse events were also analysed. RESULTS: Mean IOP decreased from 18.1 ± 5.0 mmHg at baseline to 14.8 ± 3.7 mmHg at 12 months (18.2% reduction, P < 0.001). Concomitantly, the mean number of glaucoma medications decreased from 2.5 ± 1.4 to 1.7 ± 1.2 (32% reduction, P = 0.002). The proportion of eyes achieving an IOP reduction of more than 20% from baseline was 37.5% (n = 15) at 12 months. At 12 months, 67.5% and 82.5% achieved a medicated IOP ≤ 16 and ≤18 mmHg, respectively. No severe complications were reported. CONCLUSION: Excisional goniotomy with KDB achieves a statistically significant IOP and antiglaucoma medication reduction in severe or refractory glaucoma over a period of 12 months. While its efficacy decreases with time, its favourable safety profile makes it a potentially useful primary or adjunctive procedure in high-risk eyes.

Updates on the Diagnosis and Management of Glaucoma.

Glaucoma is the leading cause of blindness throughout the world (after cataracts); therefore, general physicians should be familiar with the diagnosis and management of affected patients. Glaucomas are usually categorized by the anatomy of the anterior chamber angle (open vs narrow/closed), rapidity of onset (acute vs chronic), and major etiology (primary vs secondary). Most glaucomas are primary (ie, without a contributing comorbidity); however, several coexisting ophthalmic conditions may serve as the underlying etiologies of secondary glaucomas. Chronic glaucoma occurs most commonly; thus, regular eye examinations should be performed in at-risk patients to prevent the insidious loss of vision that can develop before diagnosis. Glaucoma damages the optic nerve and retinal nerve fiber layer, leading to peripheral and central visual field defects. Elevated intraocular pressure (IOP), a crucial determinant of disease progression, remains the only modifiable risk factor; thus, all current treatments (medications, lasers, and operations) aim to reduce the IOP. Pharmacotherapy is the usual first-line therapy, but noncompliance, undesirable adverse effects, and cost limit effectiveness. Laser and surgical treatments may lower IOP significantly over long periods and may be more cost effective than pharmacotherapy, but they are plagued by greater procedural risks and frequent treatment failures. Traditional incisional procedures have recently been replaced by several novel, minimally invasive glaucoma surgeries with improved safety profiles and only minimal decreases in efficacy. Minimally invasive glaucoma surgeries have dramatically transformed the surgical management of glaucoma; nevertheless, large, randomized trials are required to assess their long-term efficacy.

Using Enhanced Depth Imaging Optical Coherence Tomography-Derived Parameters to Discriminate between Eyes with and without Glaucoma: A Cross-Sectional Comparative Study.

INTRODUCTION: New technologies have been developed in order to decrease interpersonal influence and subjectivity during the glaucoma diagnosis process. Enhanced depth imaging spectral-domain OCT (EDI OCT) has turned up as a favorable tool for deep optic nerve head (ONH) structures assessment. OBJECTIVE: A prospective cross-sectional study was conducted to compare the diagnostic performance of different EDI OCT-derived parameters to discriminate between eyes with and without glaucoma. MATERIAL AND METHODS: The following ONH parameters were measured: lamina cribrosa (LC) thickness and area; prelaminar neural tissue (PLNT) thickness and area; average Bruch's membrane opening - minimum rim width (BMO-MRW), superior BMO-MRW, and inferior BMO-MRW. Peripapillary retinal nerve fiber layer (pRNFL) thickness was also obtained. RESULTS: Seventy-three participants were included. There were no significant differences between AUCs for average BMO-MRW (0.995), PLNT area (0.968), and average pRNFL thickness (0.975; p ≥ 0.089). However, AUCs for each of these 3 parameters were significantly larger than LC area AUC (0.701; p ≤ 0.001). Sensitivities at 80% specificity were: PLNT area = 92.3%, average BMO-MRW = 97.4%, and average pRNFL thickness = 94.9%. CONCLUSIONS: Comparing the diagnostic performance of different EDI OCT ONH parameters to discriminate between eyes with and without glaucoma, we found better results for neural tissue-based indexes (BMO-MRW and PLNT area) compared to laminar parameters. In this specific population, these neural tissue-based parameters (including PLNT area, which was investigated by the first time in the present study) had a diagnostic performance comparable to that of the conventional pRNFL thickness protocol.

Endophthalmitis following combined cataract extraction and placement of an iStent trabecular bypass device.

PURPOSE: To report a case of post-operative endophthalmitis following combined cataract extraction and minimally invasive glaucoma surgery with placement of the iStent drainage device. OBSERVATION: An 87-year-old woman with a nuclear sclerotic cataract and primary open angle glaucoma underwent elective phacoemulsification cataract extraction with iStent placement. Surgery was complicated only by the inability to properly place the second iStent despite several attempts. At 4 days post-operatively she was diagnosed with endophthalmitis. Despite the prompt intravitreal injections of broad spectrum antibiotics, she lost all perception of light. Cultures of anterior chamber aspirates failed to identify a causative organism. CONCLUSION AND IMPORTANCE: In what we believe to be the first report of endophthalmitis associated with placement of the iStent, complete loss of vision occurred. Surgeons need to be aware that iStent placement may be complicated by severe endophthalmitis.

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.

Glaucoma Surgery with Soaked Sponges with Mitomycin C vs Sub-Tenon Injection: Short-term Outcomes.

AIM: The aim of this study is to compare the outcomes, success rates, complications, and number of interventions of the trabeculectomy surgery with mitomycin C (MMC) in two different techniques: conventional soaked sponges and sub-Tenon injection. MATERIALS AND METHODS: An observational retrospective study was performed with 79 eyes of 64 participants who underwent a glaucoma surgery with MMC. The conventional sponge soaked with MMC 0.03% for 3 minutes over the scleral flap (group I) and the subtenon injection of 0.1 mL of MMC 0.03% (group II) techniques were used to deliver the MMC. The data collected were patient demographics, preoperative intraocular pressure (IOP), central corneal thickness (CCT), number of pre- and postoperative ocular hypotensive drugs, postoperative complications, number of interventions, and need of further glaucoma surgery. RESULTS: Seventy-nine eyes were divided into two: 39 eyes (49.37%) in group I and 40 eyes (50.63%) in group II. Trabeculectomy was performed in 53.17% and phacotrabeculectomy in 46.83%. The IOP decreased from 18.0 ± 11.0 mm Hg at the baseline to 10.0 ± 3.0 mm Hg at the last visit in group I and, in group II, from 16.0 ± 10.0-13.0 ± 6.0 mm Hg (median ± ID), p < 0.001. There were no significant differences between the groups regarding demographics, median follow-up, IOP in baseline, CCT, drugs reduction, success criteria adopted, postsurgical interventions, surgical complications, and need for new procedures (p > 0.05). CONCLUSION: Sub-Tenon injection of MMC is a safe and as effective as the conventional soaked sponge method in trabeculectomies. This method reduces surgical time and sponge-related risks with equivalent surgical efficacy. CLINICAL SIGNIFICANCE: As trabeculectomy is still the most common surgical procedure to reduce IOP and scar formation is one of the main causes of surgical failure, it is important to develop surgical techniques to improve its outcomes. HOW TO CITE THIS ARTICLE: Guimarães MEV, de Pádua Soares Bezerra B, et al. Glaucoma Surgery with Soaked Sponges with Mitomycin C vs Sub-Tenon Injection: Short-term Outcomes. J Curr Glaucoma Pract 2019;13(2):50-54.

Outcomes of Micropulse Transscleral Cyclophotocoagulation in Eyes With Good Central Vision.

PRECIS: This study is the first to report micropulse transscleral cyclophotocoagulation (MP-TSCPC) use in only good vision patients. MP-TSCPC significantly reduced intraocular pressure (IOP) and glaucoma medication use without any significant reduction in visual acuity at every postoperative follow-up point. PURPOSE: To evaluate outcomes of MP-TSCPC in eyes with baseline best-corrected visual acuity (BCVA) of ≥20/60. METHODS: A retrospective review of patients who underwent MP-TSCPC at Mayo Clinic and Ross Eye Institute from July 2016 to August 2017 with BCVA of ≥20/60, and a minimum of 3 months follow-up. RESULTS: A total of 61 eyes of 46 patients (68.80±17.12 y) underwent MP-TSCPC with a mean follow-up of 10.2±3.1 months. Mean IOP and mean number of glaucoma medications used were significantly reduced from baseline at every follow-up time point (P<0.0001). At month 12, mean IOP was reduced 40.2% from baseline with 85.4% of the patients having an IOP reduction of ≥20%, and mean glaucoma medication use reduced by 0.82±0.53 with 79.6% of the patients having a reduction of ≥1 medication. There was no significant reduction in BCVA from baseline at any follow-up point (P>0.05), except for 10 eyes with a vision loss of ≥2 lines and 5 out of 10 eyes had cataract progression. The probability of complete success (IOP range, 6 to 21 mm Hg or ≥20% IOP reduction; BCVA loss ≤2 lines, no reoperation for glaucoma) was 74.14%, 83.61%, 84.21%, and 75.0% at months 1, 3, 6, 12, respectively. The probability of qualified success (above criteria for IOP, no reoperation and BCVA loss >2 lines) was 81.03%, 91.80%, 94.74%, and 93.75% at months 1, 3, 6, 12, respectively. CONCLUSIONS: MP-TSCPC should be considered earlier in the management of glaucoma and can possibly be offered as an alternative to incisional glaucoma surgeries.

12-Month Retrospective Comparison of Kahook Dual Blade Excisional Goniotomy with Istent Trabecular Bypass Device Implantation in Glaucomatous Eyes at the Time of Cataract Surgery.

PURPOSE: To compare the efficacy and safety of combined cataract extraction and either excisional goniotomy performed with the Kahook Dual Blade (KDB; phaco-KDB group) or single iStent trabecular bypass implantation (phaco-iStent group) in eyes with mild to moderate glaucoma and visually significant cataract. METHODS: This was a retrospective analysis of 315 eyes from 230 adults with mild or moderate glaucoma treated with one or more intraocular pressure (IOP)-lowering medications (190 eyes of 134 subjects in the phaco-KDB group and 125 eyes of 96 subjects in the phaco-iStent group) that required no subsequent surgical intervention for IOP control through 12 months of follow-up. Data included best-corrected visual acuity (BCVA), IOP, and IOP-lowering medications, collected preoperatively and at 1 week and 1, 3, 6, and 12 months postoperatively as well as intraoperative and postoperative adverse events. The primary efficacy outcomes were the proportion of subjects in each group achieving ≥ 20% IOP reduction and ≥ 1 medication reduction at month 12. Subgroup analysis by baseline IOP (≤ 18 mmHg vs. > 18 mmHg) was also performed. RESULTS: Mean (standard error) baseline IOP was 18.2 (0.3) mmHg in the phaco-KDB group and 16.7 (0.3) mmHg in the phaco-iStent group (p = 0.001). Statistically significant mean IOP and mean IOP medication reductions from baseline were achieved at all time points in both groups. Mean IOP reductions were significantly greater in the phaco-KDB group than in the phaco-iStent group at all time points including month 12 [- 5.0 (0.3) mmHg vs. - 2.3 (0.4) mmHg, p < 0.001], while mean medication reductions were similar between groups at all time points except week 1, when greater mean medication reduction was seen in the phaco-iStent group (- 1.23 vs. - 0.60 medications, p < 0.001). At month 12, IOP reductions ≥ 20% were achieved by 64.2% and 41.6% (p < 0.001) in the phaco-KDB and phaco-iStent groups, respectively, and IOP medication reductions of ≥ 1 medication were achieved by 80.4% and 77.4% (p = 0.522), respectively. Intraocular pressure subgroup analysis revealed significant reductions in IOP-lowering medications without compromise of IOP control in lower IOP subgroups and significant reductions in both IOP and IOP-lowering medications in the higher IOP subgroups. The most common adverse events were transient IOP elevations and transient anterior chamber inflammation, which occurred with similar frequency in both groups and resolved spontaneously. CONCLUSION: Goniotomy with the KDB lowered IOP significantly more than iStent implantation, with few adverse events in both groups. In eyes with mild to moderate glaucoma undergoing combined cataract extraction and glaucoma surgery, goniotomy with the KDB can safely deliver statistically significant and clinically meaningful reductions in both IOP and IOP medication burden through 12 months of follow-up. FUNDING: New World Medical, Inc., provided funding for the study, medical writing assistance, Rapid Service Fees, and the open access fee.

Structure-function relationships in glaucoma using enhanced depth imaging optical coherence tomography-derived parameters: a cross-sectional observational study.

BACKGROUND: To investigate structural and functional correlations in glaucoma patients using enhanced depth imaging spectral-domain optical coherence tomography (EDI OCT)-derived parameters. METHODS: We prospectively enrolled healthy participants and glaucomatous patients with a wide range of disease stages. All participants underwent visual field (VF) testing (SITA - Standard 24-2; Carl Zeiss Meditec, Dublin, CA) and EDI OCT imaging (Spectralis; Heidelberg Engineering Co., Heidelberg, Germany). The following optic nerve head parameters were measured on serial vertical EDI OCT B-scans by two experienced examiners masked to patients clinical data: lamina cribrosa (LC) thickness and area, prelaminar neural tissue thickness and area, anterior LC depth, Bruch's membrane opening (BMO) and average, superior, and inferior BMO-minimum rim width (BMO-MRW). Only good quality images were considered, and whenever both eyes were eligible, one was randomly selected for analysis. Scatter plots were constructed to investigate correlations between each anatomic parameter and patient's VF status (based on VF index [VFI] values). RESULTS: A total of 73 eyes of 73 patients were included. All EDI OCT parameters evaluated differed significantly between glaucomatous and control eyes (P ≤ 0.045). A secondary analysis, in which glaucomatous patients were divided according to VF mean deviation index values into 3 groups (mild [G1; > - 6 dB], moderate [G2; - 6 to - 12 dB] and advanced [G3; <- 12 dB] glaucoma), revealed that average BMO-MRW was the EDI OCT parameter that presented more significant differences between the different stages of glaucoma. Significant structure-function correlations were found between VFI values and prelaminar neural tissue area (R2 = 0.20, P = 0.017), average BMO-MRW (R2 = 0.35, P ≤ 0.001), superior BMO-MRW (R2 = 0.21, P = 0.012), and inferior BMO-MRW (R2 = 0.27, P = 0.002). No significant correlations were found for LC area and anterior LC depth (P ≥ 0.452). CONCLUSIONS: Evaluating the distribution pattern and structure-function correlations of different laminar and prelaminar EDI OCT-derived parameters in glaucomatous patients, we found better results for neural tissue-based indexes (compared to LC-derived parameters). The diagnostic utility of each parameter deserves further investigations.

Six-Month Outcomes of Goniotomy Performed with the Kahook Dual Blade as a Stand-Alone Glaucoma Procedure.

INTRODUCTION: To characterize the reduction in intraocular pressure (IOP) and IOP-lowering medication use following goniotomy via trabecular meshwork excision performed using the Kahook Dual Blade as a stand-alone procedure in adult eyes with glaucoma uncontrolled on a regimen of 1-3 topical IOP-lowering medications. METHODS: In this retrospective analysis, data from consecutive patients undergoing goniotomy with the Kahook Dual Blade by 11 surgeons were analyzed. Preoperative, intraoperative, and postoperative follow-up data through 6 months of follow-up were collected. The primary efficacy endpoint was IOP reduction from preoperative baseline; reduction in IOP-lowering medication use was a secondary endpoint. RESULTS: Data were collected from 53 eyes of 42 subjects. Mean (± SE) preoperative IOP was 23.5 ± 1.1 mmHg, and from day 1 through 6 months of postoperative follow-up mean IOP reductions of 7.0-10.3 mmHg (29.8-43.8%; p < 0.001 at each time point) were observed. Mean preoperative medication use was 2.5 ± 0.2 medications per eye and was reduced by month 6 to 1.5 ± 0.2 (a 40.0% reduction; p < 0.05). Eyes with higher baseline IOP experienced mean IOP reductions of 13.7 mmHg (- 46.4%) at month 6, while eyes with lower baseline IOP experienced mean IOP reductions of 3.8 mmHg (- 21.0%) at month 6. Mean medications were reduced by 1.3 medications in high-IOP eyes and by 0.9 in low-IOP eyes at month 6. No significant sight-threatening adverse events were observed. CONCLUSIONS: Goniotomy via trabecular meshwork excision performed using the Kahook Dual Blade effectively and safely lowered IOP when performed as a stand-alone procedure in eyes with glaucoma. The significant drop in IOP met or exceeded the recommended targets for these glaucoma patients. FUNDING: New World Medical, Inc.

Increased Iris Stiffness in Patients With a History of Angle-Closure Glaucoma: An Image-Based Inverse Modeling Analysis.

Purpose: Previous studies have shown that iris mechanical properties may play a role in the pathophysiology of primary angle-closure glaucoma (PACG). Such studies, however, were not conducted in vivo and as such were limited in application and scope, especially for the development of diagnostic methods or new treatment options. The purpose of this study was to quantify in vivo iris mechanical properties both in patients with a history of angle-closure glaucoma and in healthy volunteers. Methods: We acquired optical coherence tomography scans of anterior segments under standard and dim light conditions. Using a combination of finite element simulation and an inverse fitting algorithm, we quantified the stiffness of the iris. Results: The irides in the eyes of patients with a history of PACG were significantly stiffer when compared with healthy control irides, a result consistent with ex vivo studies. This result was independent of the compressibility assumption (incompressible: 0.97 ± 0.14 vs. 2.72 ± 0.71, P = 0.02; compressible: 0.89 ± 0.13 vs. 2.57 ± 0.69, P = 0.02) when comparing the normalized elastic modulus of the iris between patients with PACG and healthy controls. Conclusions: Our noninvasive, in vivo quantification is free of numerous ethical issues and potential limitations involved with ex vivo examinations. If further studies confirm that the iris stiffness is an omnipresent PACG risk factor and a mechanistic role between increased iris stiffness and angle-closure glaucoma does exist, treatment methods such as lowering the iris stiffness can be developed.

12-Month Outcomes of Goniotomy Performed Using the Kahook Dual Blade Combined with Cataract Surgery in Eyes with Medically Treated Glaucoma.

INTRODUCTION: To describe the 12-month efficacy and safety of goniotomy performed using the Kahook Dual Blade (KDB) in combination with cataract surgery in eyes with medically treated open-angle glaucoma (OAG). METHODS: This was a prospective, interventional case series conducted at seven centers in North America. Consecutive patients with medically treated OAG and visually significant cataract underwent phacoemulsification combined with goniotomy (PE + goniotomy) using KDB. Indications for glaucoma surgery included reduction of intraocular pressure (IOP) and reduction of IOP-lowering medications. De-identified data were collected and included pre-, intra-, and postoperative data on IOP, the use of IOP-lowering medications, and adverse events through 12 months of follow-up. RESULTS: Among 52 eyes undergoing surgery, mean IOP was reduced from 16.8 ± 0.6 mmHg at baseline to 12.4 ± 0.3 mmHg at month 12 (P < 0.001), a 26.2% reduction. Mean IOP across time points ranged from 12.4-13.3 mmHg during follow-up. The mean number of topical IOP-lowering medications was reduced from 1.6 ± 0.2 at baseline to 0.8 ± 0.1 at month 12 (P < 0.05), a 50.0% reduction. At month 12, 57.7% of eyes had IOP reduction ≥ 20% from baseline, and 63.5% were on ≥ 1 fewer IOP-lowering medications. In subgroup analysis, 84.6% of eyes with lower mean baseline IOP were using ≥ 1 fewer medications at month 12, and 100% of eyes with higher mean baseline IOP had IOP reductions ≥ 20%. The most common postoperative adverse events were pain/irritation (n = 4, 7.7%), opacification of the posterior lens capsule (n = 2, 3.8%), and IOP spike > 10 mmHg (n = 2, 3.8%). CONCLUSION: PE + goniotomy using the KDB significantly lowers both IOP and dependence on IOP-lowering medications in eyes with OAG. Adverse events were not sight-threatening and typically resolved spontaneously. FUNDING: New World Medical, Inc.

Goniotomy Using the Kahook Dual Blade in Severe and Refractory Glaucoma: 6-Month Outcomes.

PURPOSE: The purpose of the study is to describe short-term efficacy and safety of goniotomy with trabecular meshwork excision using the Kahook Dual Blade (KDB, New World Medical Inc., Rancho Cucamonga, CA) in patients with severe or refractory glaucoma. METHOD: Retrospective multicentric case series of 53 eyes with severe or refractory glaucoma as defined by ICD-10 conducted in the United States, Mexico, and Switzerland. Primary efficacy outcome was a ≥20% decrease in intraocular pressure (IOP) from baseline at 6 months. Secondary efficacy outcome measures were probability of achieving an IOP≤14 or 18 mm Hg at 6 months and the mean IOP change from baseline at 6 months. Medication use required to obtain target IOP at last follow up and adverse effects were analyzed. RESULTS: The proportion of eyes achieving an IOP reduction of >20% from preoperative baseline at 6 months was 57.7% (n=30). The mean IOP decreased from 18.4±6.1 mm Hg at baseline to 13.9±3.5 mm Hg at month 6 (23.9% reduction; P<0.001). At 6 months, 63.5% and 92.3% achieved an IOP≤14 and ≤18 mm Hg, respectively, and the mean number of glaucoma medications was reduced by 1.2±1.3 (36.6%) compared with baseline (P<0.001). The most common adverse event was hyphema (n=29, 34.9%) with spontaneous resolution in all cases. No severe complications were reported. One case presented with uncontrolled IOP and required glaucoma drainage device surgery at 1 month. CONCLUSIONS: Goniotomy with trabecular meshwork excision using the KDB could be an alternative surgery for severe or refractory glaucoma, significantly reducing IOP and medication use at 6 months, with a low rate of complications.

A multicenter retrospective comparison of goniotomy versus trabecular bypass device implantation in glaucoma patients undergoing cataract extraction.

PURPOSE: The aim of this study was to compare intraocular pressure (IOP) outcomes in eyes with cataract and glaucoma undergoing phacoemulsification (phaco) in combination with goniotomy using the Kahook Dual Blade (KDB) or implantation of a single iStent trabecular bypass device. METHODS: Retrospective analysis of IOP and IOP-lowering medication reduction in eyes undergoing phaco-goniotomy with KDB (n=237) or phaco-iStent (n=198). Preoperative, intraoperative, and postoperative data were collected through 6 months of follow-up. Outcome measures included mean IOP reduction, mean reduction in IOP-lowering medications, and the proportion of eyes achieving ≥20% IOP reduction or ≥1 medication reduction from baseline. RESULTS: Mean IOP in the phaco-goniotomy with KDB group decreased from 17.9±4.4 mmHg at baseline to 13.6±2.7 mmHg at Month 6 (P<0.001), with mean medication use decreasing from 1.7±0.9 to 0.6±1.0 (P<0.001). In the phaco-iStent group, mean IOP decreased from 16.7±4.4 mmHg to 13.9±2.7 mmHg (P<0.001), with mean IOP-lowering medication use decreasing from 1.9±0.9 to 1.0±1.0 (P<0.001). Mean IOP reduction from baseline was significantly greater in the phaco-goniotomy with KDB group at Month 6 (phaco-goniotomy with KDB -4.2 mmHg [23.7%] vs phaco-iStent -2.7 mmHg [16.4%]; P<0.001). IOP-lowering medication reduction was greater in the phaco-goniotomy with KDB group compared to the phaco-iStent group (1.1 vs 0.9 medications, respectively; P=0.001). The most common adverse event was IOP spikes occurring in 12.6% of phaco-iStent eyes and 6.3% of phaco-goniotomy with KDB eyes (P=0.024). CONCLUSION: Goniotomy with the KDB combined with cataract surgery significantly lowers both IOP and the need for IOP-lowering medications compared to cataract extraction with iStent implantation in glaucomatous eyes through 6 months of postoperative follow-up.

Appropriate Objective Functions for Quantifying Iris Mechanical Properties Using Inverse Finite Element Modeling.

Quantifying the mechanical properties of the iris is important, as it provides insight into the pathophysiology of glaucoma. Recent ex vivo studies have shown that the mechanical properties of the iris are different in glaucomatous eyes as compared to normal ones. Notwithstanding the importance of the ex vivo studies, such measurements are severely limited for diagnosis and preclude development of treatment strategies. With the advent of detailed imaging modalities, it is possible to determine the in vivo mechanical properties using inverse finite element (FE) modeling. An inverse modeling approach requires an appropriate objective function for reliable estimation of parameters. In the case of the iris, numerous measurements such as iris chord length (CL) and iris concavity (CV) are made routinely in clinical practice. In this study, we have evaluated five different objective functions chosen based on the iris biometrics (in the presence and absence of clinical measurement errors) to determine the appropriate criterion for inverse modeling. Our results showed that in the absence of experimental measurement error, a combination of iris CL and CV can be used as the objective function. However, with the addition of measurement errors, the objective functions that employ a large number of local displacement values provide more reliable outcomes.

Goniotomy with a single-use dual blade: Short-term results.

PURPOSE: To evaluate the intraocular pressure (IOP)-lowering efficacy and safety of a single-use dual blade (Kahook) in patients with mild to end-stage glaucoma. SETTING: International multicenter ophthalmic care centers. DESIGN: Prospective interventional case series. METHODS: Consecutive patients with glaucoma who had phacoemulsification plus goniotomy with the single-use dual blade were enrolled in this study. Each center collected deidentified clinical data, including preoperative and postoperative IOP, medication use, adverse events, and whether additional surgery was required during a 6-month follow-up. RESULTS: Of the 71 eyes included in this study, 70% had primary open-angle glaucoma. Other diagnoses included angle-closure, pigmentary, pseudoexfoliative, and normal-tension glaucoma. Sixty-five percent of eyes were classified as having mild to moderate glaucoma and 35%, severe glaucoma. The mean baseline IOP decreased from 17.4 mm Hg ± 5.2 (SD) to 12.8 ± 2.6 mm Hg 6 months postoperatively and the hypotensive medication use decreased from 1.6 ± 1.3 to 0.9 ± 1.0, respectively (P < .001 and P = .005, respectively). The most common observation was blood reflux during surgery (39.4%). CONCLUSION: Single-use dual blade goniotomy plus phacoemulsification resulted in a significant and sustained reduction in IOP and a decrease in glaucoma medications after 6 months of follow-up.