Understanding Perspectives on Presbyopia and Use of Pilocarpine HCl 1.25% Twice Daily from Participants of the Phase 3 VIRGO Study.

INTRODUCTION: The phase 3, randomized, vehicle-controlled, 14-day VIRGO study evaluated the efficacy and safety of twice-daily dosing of pilocarpine hydrochloride ophthalmic solution 1.25% (Pilo) in presbyopia. On VIRGO exit, a companion study was conducted to assess the patient experience with presbyopia and satisfaction with Pilo. METHODS: Recruited individuals completed the Presbyopia Patient Satisfaction Questionnaire (PPSQ) plus a three-part exit survey, or a live interview. The PPSQ evaluated respondents' experience with Pilo. Survey parts 1 and 2 evaluated experience managing presbyopia before and during VIRGO, respectively; part 3 assessed future possibilities of using Pilo in real-world situations. The interview further informed the interviewees' experience with presbyopia and Pilo. The primary endpoint was responders (%) in each rating category of the PPSQ items 1-7; the secondary endpoints were summary of categorical (survey) and qualitative (interviews) responses. RESULTS: The PPSQ and survey included 62 participants who received Pilo (N = 28) or vehicle (N = 34) in VIRGO; the interview included ten participants (Pilo, N = 4; vehicle, N = 6). Per the PPSQ, 64.3% of Pilo users reported vision improvement, including 17.9% with complete improvement; ≥ 46.4% were satisfied/very satisfied with their ability to perform daily activities, see up close unaided, and read in dim light. Among vehicle users, these percentages were 35.3%, 0%, and ≤ 23.5%, respectively. In both subgroups, ≥ 67.9% were interested in using Pilo or Pilo and eyeglasses/contact lenses in the future. Per the interview, vehicle users (n = 6/6) found the eyedrop easy to use but none experienced meaningful near-vision improvements, stopped using other correction method(s) part of the day, were satisfied with the eyedrop, preferred it over their previous correction method(s), or would continue using it if prescribed. Conversely, 75% (n = 3/4) of Pilo users responded positively to each of these six criteria. CONCLUSIONS: Findings validate the VIRGO results and improve our understanding of the patient experience, demonstrating improved vision and satisfaction with Pilo (vs. vehicle) when performing daily activities.

Canaloplasty and Trabeculotomy with the OMNI System in Patients with Open-Angle Glaucoma: Two-Year Results from the ROMEO Study.

Purpose: To provide extended safety and effectiveness follow-up for eyes treated with circumferential canaloplasty and trabeculotomy (CP+TR) that were included in the 12-month ROMEO study. Setting: Seven multi-subspecialty ophthalmology practices located in 6 states (Arkansas, California, Kansas, Louisiana, Missouri, and New York). Design: Retrospective, multicenter, IRB approved. Subjects: Eligible eyes had mild-moderate glaucoma and were treated with CP+TR with cataract surgery or as a standalone intervention. Methods: Main outcome measures were mean IOP, mean number of ocular hypotensive medications, mean change in number of medications, proportion of patients with a ≥20% reduction in IOP or with IOP ≤18 mmHg, and proportion of patients medication free. Safety outcomes were adverse events and secondary surgical interventions (SSI). Results: Eight surgeons at 7 centers contributed 72 patients stratified by pre-operative intraocular pressure (IOP); >18 mmHg (Grp1), ≤18 mmHg (Grp2). Mean follow-up of 2.1 years (min 1.4, max 3.5). 2-year IOP (SD) was 15.6 mmHg (-6.1 mmHg, -28% from baseline) on 1.4 medications (-0.9, -39%) for Grp1 with cataract surgery; 14.7 mmHg (-7.4 mmHg, -33% from baseline) on 1.6 medications (-0.7, -15%) for Grp1 standalone, 13.7 mmHg (-0.6 mmHg, -4.2%) on 1.2 medications (-0.8, -35%) for Grp2 with cataract surgery, 13.3 mmHg (-2.3 mmHg, -14.7%) on 1.2 medications (-1.0, -46%) for Grp2 standalone. The proportion of patients at 2 years with either a ≥20% IOP reduction or IOP between 6 and 18 mmHg and no increase in medication or SSI was 75% (54 of 72, 95% CI 69.9%, 80.1%). One-third of patients (24 of 72) were medication free whereas 9 of 72 were pre-surgical. No device-related adverse events during extended follow-up; 6 eyes (8.3%) required additional surgical or laser intervention for IOP control after 12 months. Conclusion: CP+TR provides effective IOP control that is sustained for 2 years or more.

Canaloplasty and trabeculotomy with the OMNI® surgical system in OAG with prior trabecular microbypass stenting.

PURPOSE: Evaluate effectiveness and safety outcomes for patients treated with canaloplasty and trabeculotomy previously treated with a trabecular microbypass stent (TBS). METHODS: Retrospective, multicenter, IRB approved study. Patients treated with TBS (iStent/iStent inject, Glaukos) and subsequently with OMNI surgical system (OSS) (Sight Sciences). From 5 practices in 5 US states. Open-angle glaucoma (OAG), minimum 3 months follow-up after OSS surgery, Pre-OSS IOP ≥ 17 mmHg on ≥ 1 medication. No glaucoma procedures between TBS and OSS. ENDPOINTS: proportion with ≥ 20% reduction in IOP, IOP between 6 and 18 mmHg, mean IOP, change in IOP, mean number of medications. Adverse events and secondary surgical interventions (SSI). Mann-Whitney rank sum test compared pre-OSS IOP and medications with follow-up. RESULTS: Twenty seven patients. Average age (SD) 72.2 (10.8), 22/27 primary OAG (82%), mean MD - 6.2 (7.0) dB. Mean IOP before OSS 22.3 (4.3) mmHg on 2.2 (1.3) medications. At last follow-up (mean 11 months) IOP was 17.2 mmHg on 1.8 medications, - 5.1 mmHg (- 23%, p < .001), - 0.4 meds (- 18%, p = .193); ≥ 20% IOP reduction (41%), IOP ≤ 18 (56%). Adverse events were non-serious. Hyphema > 1 mm (3, 11%), BCVA decrease (4, 15%), IOP spike (2, 7%). SSI (4, 15%) had higher pre-OSS IOP (23.4 mmHg) and worse MD (- 9.6 dB). CONCLUSION: Patients uncontrolled by medication and a prior TBS would once have been candidates for trabeculectomy and tube shunts. OSS offered a minimally invasive option that provided IOP control and avoidance of traditional surgery for the majority over follow-up averaging 11 months and up to 42 months.

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.

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.

Quality of Life in Primary Open-Angle Glaucoma and Cataract: An Analysis of VFQ-25 and OSDI From the iStent inject® Pivotal Trial.

OBJECTIVE: To assess quality of life (QOL) as measured by patient-reported outcomes (PRO) within the iStent inject® pivotal trial. DESIGN: Randomized controlled trial analysis of secondary outcomes. METHODS: The Vision Function Questionnaire (VFQ-25) and Ocular Surface Disease Index (OSDI) questionnaire were administered at baseline and at months 1, 6, 12, and 24. PRO responders were defined as patients reaching improvement based on minimally important differences. RESULTS: A total of 505 patients were randomized (386 iStent inject® [Glaukos], 119 surgery alone). The iStent inject® group exhibited a greater percentage of PRO responders across all follow-up visits over 24 months, averaging 58.0% vs 45.8%; P < .05 for VFQ-25 composite scores and 56.7% vs 48.9%; P < .05 for OSDI composite scores. Odds of being a responder in the iStent inject® group was 60% (P < .05) higher for the VFQ-25 and 32% (P > .05) higher for the ODSI. Driving (49.0% vs 28.8%; P < .05), ocular pain (59.3% vs 47.2%; P < .05), and general vision (71.8% vs 60.0%; P < .05) were the VFQ-25 subscales responsible for differences between treatment groups. At month 24, 76.5% of VFQ-25 responders and 62.5% of nonresponders were medication free regardless of treatment group (P < .05). CONCLUSIONS: Exploratory analysis suggests that by reducing medication dependence, implantation with the micro-scale iStent inject® device with cataract surgery may improve QOL vs cataract surgery alone over 24 months, with improvements influenced by ocular symptoms and vision-related activities.

Canaloplasty and Trabeculotomy with the OMNI System in Pseudophakic Patients with Open-Angle Glaucoma: The ROMEO Study.

PURPOSE: Provide outcomes up to 12 months postsurgically for sequential canaloplasty and trabeculotomy with the OMNI surgical system (Sight Sciences, Inc) in pseudophakic patients with mild to moderate open-angle glaucoma. DESIGN: Retrospective, multicenter, single-arm study conducted at 10 multi-subspecialty ophthalmology practices and surgery centers located in 7 states (Arkansas, California, Kansas, Louisiana, Missouri, New York, and Texas). PARTICIPANTS: Eligible patients were pseudophakic, with mild/moderate open-angle glaucoma, 12-month follow-up, and medicated intraocular pressure (IOP) ≤36 mmHg on ≤4 medications preoperatively. One eye per patient was enrolled. METHODS: Institutional Review Board approved. All available cases meeting eligibility criteria were enrolled. Analysis of secondary end points was stratified by baseline (BL) IOP (>18 mmHg in group 1 and ≤18 mmHg in group 2) recognizing that treatment goals differed depending on BL IOP. MAIN OUTCOME MEASURES: Primary success was defined as the proportion of patients with ≥20% reduction in IOP from BL or IOP between 6 and 18 mmHg (inclusive) and on the same or fewer medications without secondary surgical intervention (SSI). Other effectiveness end points included mean IOP and number of medications at 12 months. Safety end points were best-corrected visual acuity (BCVA), adverse events (AEs), and SSIs. RESULTS: Forty-eight patients were enrolled, 24 in each group. Primary success was met by 73%. Mean IOP was reduced in group 1 (21.8 to 15.6 mmHg, P < 0.0001) and remained controlled in group 2 (15.4 to 13.9 mmHg, P = 0.24). Medications went from 1.7 ± 1.3 to 1.2 ± 1.3 (P = 0.024) in group 1 and from 2.0 ± 1.3 to 1.3 ± 1.3 (P = 0.003) in group 2. Adverse events were typical for the patient population undergoing angle surgery. Those reasonably related to the procedure were mild inflammation (13%), IOP spikes (6%), hyphema, corneal edema, and BCVA loss (all 4%). Five patients (10%) required an SSI. CONCLUSIONS: The sequential combination of canaloplasty followed by trabeculotomy performed as stand-alone procedures using the OMNI system in pseudophakic patients with open-angle glaucoma provides effective IOP reduction or sustained IOP control and meaningful medication reduction for up to 12 months postoperatively.

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.

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.

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.

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.

The Effects of Glaucoma Drainage Devices on Oxygen Tension, Glycolytic Metabolites, and Metabolomics Profile of Aqueous Humor in the Rabbit.

PURPOSE: Glaucoma drainage device (GDD) implantation can lead to corneal decompensation. We evaluated changes over time in oxygen tension and in the metabolic environment of the aqueous humor after GDD implantation in the rabbit eye. METHODS: Ahmed Glaucoma Valves were implanted in the left eyes of eight male New Zealand white rabbits. Right eyes were used as a control. Oxygen tension was measured immediately before surgery and at 1 and 2 months postoperation. Aqueous humor was collected from the surgical and control eyes at 1, 2, and 5 months postoperation. Aqueous humor samples collected at 1 and 5 months postoperation were selected for broad-spectrum metabolomics analysis using ultra-performance liquid chromatography-time of flight-mass spectrometry (UPLC TOF-MS). Multivariate analysis methods were used to identify metabolite profiles that separated the surgical and control eye at 1 and 5 months. RESULTS: There was a significant decrease in oxygen tension in aqueous humor of the surgical eyes (9 mm Hg, 95% confidence interval [CI]: -14.7 to -3.5). Differences in the metabolic profiles between the surgical and control eye at 1 and 5 months were observed, as were differences for the surgical eye at 1 and 5 months. In addition, a metabolite profile was identified that differentiated the surgical eyes at 1 and 5 months. CONCLUSION: Changes in the oxygen tension and metabolic intermediates occur within the aqueous humor as early as 1 month after GDD implantation. TRANSLATIONAL RELEVANCE: Corneal decompensation following GDD implantation could be secondary to disruption of the normal aqueous circulation, resulting in hypoxia and an altered metabolic profile. Alterations to the GDD design might minimize aqueous disruption and prevent corneal decompensation.