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Gong Z, Johnstone MA, Wang RK. iStent insertion orientation and impact on trabecular meshwork motion resolved by optical coherence tomography imaging. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:076008. [PMID: 39070082 PMCID: PMC11283271 DOI: 10.1117/1.jbo.29.7.076008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 07/02/2024] [Accepted: 07/03/2024] [Indexed: 07/30/2024]
Abstract
Significance The iStent is a popular device designed for glaucoma treatment, functioning by creating an artificial fluid pathway in the trabecular meshwork (TM) to drain aqueous humor. The assessment of iStent implantation surgery is clinically important. However, current tools offer limited information. Aim We aim to develop innovative assessment strategies for iStent implantation using optical coherence tomography (OCT) to evaluate the position and orientation of the iStent and its biomechanical impact on outflow system dynamics. Approach We examined four iStents in the two eyes of a glaucoma patient. Three-dimensional (3D) OCT structural imaging was conducted for each iStent, and a semi-automated algorithm was developed for iStent segmentation and visualization, allowing precise measurement of position and orientation. In addition, phase-sensitive OCT (PhS-OCT) imaging was introduced to measure the biomechanical impact of the iStent on the outflow system quantified by cumulative displacement (CDisp) of pulse-dependent trabecular TM motion. Results The 3D structural image processed by our algorithm definitively resolved the position and orientation of the iStent in the anterior segment, revealing substantial variations in relevant parameters. PhS-OCT imaging demonstrated significantly higher CDisp in the regions between two iStents compared to locations distant from the iStents in both OD ( p = 0.0075 ) and OS ( p = 0.0437 ). Conclusions Our proposed structural imaging technique improved the characterization of the iStent's placement. The imaging results revealed inherent challenges in achieving precise control of iStent insertion. Furthermore, PhS-OCT imaging unveiled potential biomechanical alterations induced by the iStent. This unique methodology shows potential as a valuable clinical tool for evaluating iStent implantation.
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Affiliation(s)
- Zhaoyu Gong
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
| | - Murray A. Johnstone
- University of Washington, Department of Ophthalmology, Seattle, Washington, United States
| | - Ruikang K. Wang
- University of Washington, Department of Bioengineering, Seattle, Washington, United States
- University of Washington, Department of Ophthalmology, Seattle, Washington, United States
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Hengerer FH, Auffarth GU, Conrad-Hengerer I. 7-Year Efficacy and Safety of iStent inject Trabecular Micro-Bypass in Combined and Standalone Usage. Adv Ther 2024; 41:1481-1495. [PMID: 38363465 PMCID: PMC10960914 DOI: 10.1007/s12325-024-02788-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 01/17/2024] [Indexed: 02/17/2024]
Abstract
INTRODUCTION This study evaluated 7-year effectiveness and safety of second-generation trabecular micro-bypass implantation (iStent inject) either in combination with cataract surgery or as a standalone procedure (Combined or Standalone subgroups, respectively) in eyes with open-angle glaucoma. METHODS This prospective, non-randomized, unmasked, longitudinal study included 125 consecutive iStent inject cases of a single surgeon at a large German academic hospital. Patients had considerable preoperative disease burden, with mean intraocular pressure (IOP) of 23.5 mmHg, 84.8% of eyes on ≥ 2 medications, and 38.4% of eyes with prior glaucoma surgery. IOP, medications, adverse events, and secondary surgeries were assessed through 7 years in the Overall cohort and in Combined (n = 81) and Standalone (n = 44) subgroups. RESULTS Over 7-year follow-up, mean IOP decreased by 36.2-40.0% in Overall eyes, 34.1-38.9% in Combined eyes, and 39.5-43.5% in Standalone eyes (p < 0.001 at all timepoints for all groups). Meanwhile, mean medications decreased by 59.3-71.3% in Overall eyes, 57.9-69.0% in Combined eyes, and 62.1-76.2% in Standalone eyes (p < 0.001 at all timepoints in all groups). At last follow-up (mean 77.4 months; 92.8% of patients with last visit at 6 or 7 years), 83.7% of Overall eyes, 82.3% of Combined eyes, and 86.4% of Standalone eyes had achieved ≥ 20% IOP reduction vs preoperative. At last follow-up vs preoperative, 100% of eyes in all groups had the same or lower IOP and 100% had the same or lower medication regimen. Safety outcomes were favorable, with no filtration surgeries and only 4.84% of eyes experiencing clinically significant visual field loss over 7 years of follow-up. CONCLUSION iStent inject implantation with or without phacoemulsification produced significant and durable 7-year reductions in IOP (~ 34-44% reduction) and medications (~ 58-76% reduction) while preventing filtering surgery in this cohort of patients with relatively high preoperative disease burden. Combined and Standalone cases had similarly favorable effectiveness and safety.
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Affiliation(s)
- Fritz H Hengerer
- David J Apple International Laboratory of Ophthalmic Pathology, Department of Ophthalmology, International Vision Correction Research Centre (IVCRC), Buergerhospital, University of Heidelberg, Frankfurt, Germany.
- University Eye Hospital, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.
| | - Gerd U Auffarth
- University Eye Hospital, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Ina Conrad-Hengerer
- University Eye Hospital, University of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
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Martini K, Baillif S, Nahon-Esteve S, Denis P, Martel A. Intraoperative iStent versus postoperative selective laser trabeculoplasty in early glaucoma patients undergoing cataract surgery: A retrospective comparative study. J Fr Ophtalmol 2024; 47:103956. [PMID: 37783587 DOI: 10.1016/j.jfo.2023.03.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 10/04/2023]
Abstract
PURPOSE To compare the efficacy and safety of iStent inject® versus 360° selective laser trabeculoplasty (SLT) in patients with early glaucoma undergoing cataract surgery. METHODS A retrospective non-randomized study was conducted in 73 eyes divided into two groups: cataract surgery+intraoperative iStent (n=40) versus cataract surgery+postoperative SLT at one month (n=33). The primary endpoint was intraocular pressure (IOP) lowering≥20% between baseline and 6 months postoperatively. The secondary endpoints were IOP lowering at 1, 6 and 12 months, and the mean number of IOP-lowering medications at 6 and 12 months. RESULTS The mean baseline IOP was 19.1 mmHg with no significant difference between groups. The mean baseline number of IOP-lowering medications was higher in the iStent group (n=1.95) compared to the SLT group (n=1.53; P=0.04). At 6 months, 18 (60%) patients in the SLT group and 20 (51%) patients in the iStent group achieved IOP lowering≥20% with no significant difference between groups (P=0.431). At 6 months, no difference in the mean number of IOP-lowering medications was found between groups (-0.92 and -0.89 in the iStent and SLT groups, respectively). Similar results were found at 12 months. CONCLUSION These results suggest similar safety and efficacy of intraoperative iStent and postoperative 360° SLT in lowering IOP and reducing glaucoma eye drops in early glaucoma patients undergoing cataract surgery. Treatment choice should be based on the ophthalmologist's experience and on the cost-benefit ratio.
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Affiliation(s)
- K Martini
- Ophthalmology Department, University Hospital of Nice, 30, voie Romaine, 06000 Nice, France.
| | - S Baillif
- Ophthalmology Department, University Hospital of Nice, 30, voie Romaine, 06000 Nice, France
| | - S Nahon-Esteve
- Ophthalmology Department, University Hospital of Nice, 30, voie Romaine, 06000 Nice, France
| | - P Denis
- Ophtalmology Department, University Hospital of La-Croix-Rousse, grande rue de la Croix-Rousse, Lyon, France
| | - A Martel
- Ophthalmology Department, University Hospital of Nice, 30, voie Romaine, 06000 Nice, France
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Gallardo MJ, Porter M. Efficacy and Safety of Pairing iStent Inject Trabecular Micro-Bypass and iAccess Precision Blade Goniotomy in Patients with Open-Angle Glaucoma. Ophthalmol Ther 2023; 12:1973-1987. [PMID: 37178443 PMCID: PMC10287603 DOI: 10.1007/s40123-023-00726-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
INTRODUCTION This study evaluated efficacy and safety of implanting two second-generation trabecular micro-bypass stents (iStent inject/iStent inject W) with phacoemulsification, either with or without iAccess Precision Blade goniotomy, in patients with mild-to-moderate open-angle glaucoma (OAG). METHODS This retrospective, non-randomized, unmasked, dual-arm, single-site, multi-surgeon, consecutive case series evaluated all OAG eyes that underwent phacoemulsification and iStent inject implantation either as a dual procedure (group A) or paired with iAccess goniotomy (group B) from July 2020 to May 2022. Effectiveness outcomes analyzed from 1 month onward included intraocular pressure (IOP), proportions of eyes with IOP ≤ 12/≤ 15/≤ 18, proportion medication-free, and medication number. Safety outcomes at all timepoints included adverse events and secondary surgeries. RESULTS In group A, mean IOP reduced from 14.9 ± 3.2 mmHg on 1.22 ± 1.31 mean medications preoperatively (n = 63) to 13.5 ± 2.5 mmHg on 0.24 ± 0.61 medications at month 3 (n = 34; p = 0.048 IOP, p < 0.001 medications). In group B, mean IOP reduced from 16.0 ± 4.2 mmHg on 1.12 ± 1.07 medications preoperatively (n = 93) to 12.2 ± 2.3 mmHg on 0.57 ± 1.27 medications at month 3 (n = 23; p < 0.001 IOP, p = 0.003 medications). From preoperative to 3 months, the percent of eyes with IOP ≤ 12 mmHg remained at 32.4% in group A (p = 1.0) and rose from 21.7% to 60.9% in group B (p = 0.0177); eyes with IOP ≤ 15 mmHg rose from 52.9% to 76.5% in group A (p = 0.0963) and from 43.5% to 91.3% in group B (p = 0.0034). Adjusting for baseline between-group differences, group B had significantly greater postoperative IOP reduction than group A (p = 0.043); medication reductions were similar. Safety was favorable in both groups. CONCLUSIONS Phacoemulsification and iStent inject with or without iAccess Precision Blade goniotomy produced clinically meaningful and safe IOP and medication reductions. The paired iStent inject + iAccess + phacoemulsification procedure enabled greater IOP reduction and lower IOP thresholds than iStent inject + phacoemulsification. The study provides some of the first data on this paired approach and on the novel iAccess Precision Blade.
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Affiliation(s)
- Mark J. Gallardo
- El Paso Eye Surgeons, PA, 1201 North Mesa Street, Suite G, El Paso, TX 79902 USA
- Department of Ophthalmology, Texas Tech University Health Sciences Center in Lubbock, 3601, 4th St, Lubbock, TX 79430 USA
| | - Matthew Porter
- El Paso Eye Surgeons, PA, 1201 North Mesa Street, Suite G, El Paso, TX 79902 USA
- Department of Ophthalmology, Texas Tech University Health Sciences Center in Lubbock, 3601, 4th St, Lubbock, TX 79430 USA
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Effectiveness and Safety of iStent Infinite Trabecular Micro-Bypass for Uncontrolled Glaucoma. J Glaucoma 2023; 32:9-18. [PMID: 36260288 PMCID: PMC9722368 DOI: 10.1097/ijg.0000000000002141] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 10/07/2022] [Indexed: 01/24/2023]
Abstract
PRCIS The iStent Infinite Trabecular Micro-Bypass System implanted in patients with open angle glaucoma (OAG) (uncontrolled by prior surgical or medical therapy) was effective in reducing mean diurnal intraocular pressure with a favorable safety profile. PURPOSE The purpose of this study is to evaluate safety and effectiveness of the iStent infinite Trabecular Micro-Bypass System in patients with OAG uncontrolled by prior surgical or medical therapy. DESIGN Prospective, multicenter, single-arm, open-label clinical trial. METHODS Implantation of iStent infinite (3 iStent inject W stents) was performed as a stand-alone surgical procedure in eyes with OAG uncontrolled by prior incisional or cilioablative surgeries or maximum tolerated medical therapy (MTMT). Prospectively declared effectiveness endpoints were proportion of eyes achieving ≥20% mean diurnal intraocular pressure (MDIOP) reduction from baseline at month 12 on the same or fewer intraocular pressure (IOP)-lowering medication classes (responder endpoint) and mean change in MDIOP from baseline at month 12. Safety parameters included visual acuity, slit-lamp and fundus examinations, gonioscopy, perimetry, surgical complications, and adverse events. RESULTS Seventy-two eyes of 72 patients (mean age 71.9 y) with preoperative mean medicated MDIOP of 23.4±2.8 mm Hg on a mean of 3.1±0.9 IOP-lowering medication classes were enrolled: 61 eyes with failed prior surgery/ies (Failed-Surgery subgroup) and 11 eyes uncontrolled on MTMT (MTMT subgroup). A total of 76.1% of all enrolled patients met the responder endpoint (73.4% Failed-Surgery, 90.9% MTMT), with mean reduction (SE) in MDIOP at month 12 of 5.9(0.6) mm Hg [5.5(0.7) mm Hg Failed-Surgery subgroup, 8.1(0.9) mm Hg MTMT subgroup]. For patients on the same or fewer medication(s) as baseline, 53.0% achieved ≥30% MDIOP reduction without surgical interventions/other events. Safety was favorable, with no explants, infection, or device-related interventions or hypotony. CONCLUSIONS iStent infinite stand-alone surgery achieved clinically significant IOP reduction and favorable safety in patients with OAG uncontrolled by prior therapy.
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Paletta Guedes RA, Gravina DM, Paletta Guedes VM, Chaoubah A. Standalone Implantation of 2-3 Trabecular Micro-Bypass Stents (iStent inject ± iStent) as an Alternative to Trabeculectomy for Moderate-to-Severe Glaucoma. Ophthalmol Ther 2022; 11:271-292. [PMID: 34825352 PMCID: PMC8770764 DOI: 10.1007/s40123-021-00424-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 11/01/2021] [Indexed: 12/04/2022] Open
Abstract
INTRODUCTION This retrospective consecutive study compared standalone implantation of multiple (2-3) trabecular micro-bypass stents (iStent inject ± iStent) (Multi-Stent group) vs trabeculectomy + mitomycin C (Trab group) in moderate to severe open-angle glaucoma (OAG). METHODS Eligible patients underwent Multi-Stent or Trab surgery from 2018 to 2020 and had at least 3-month follow-up; visual field mean deviation (VF MD) - 6 dB or worse; inadequate prior response to maximum medications ± laser procedures; and had trabeculectomy as their next planned intervention. Primary effectiveness, safety-adjusted treatment success, was defined as ≥ 20% intraocular pressure (IOP) reduction on the same or fewer medications, without clinically significant safety events (severe complications, secondary surgeries, reinterventions). Secondary effectiveness included mean IOP and medications; qualified and complete attainment of target IOP (≤ 21/18/15/12 mmHg and > 6 mmHg); health-economic and quality-of-life (QoL) measures; and 2-vs-3-stent subgroup analysis. RESULTS The baseline groups (n = 70 Multi-Stent/40 Trab) were similar: mean IOP (21.1 mmHg/22.3 mmHg); medications (2.87/3.10 medications); disease stage (30%/35% severe); VF MD (- 10.1 dB/- 10.4 dB); and mean last follow-up (LFU, 13.1 months/15.7 months) (all differences non-significant). Primary effectiveness: treatment success at LFU was 62.9% vs 30.0% in Multi-Stent vs Trab eyes, respectively (p = 0.001). Secondary effectiveness: At LFU in Multi-Stent vs Trab groups, respectively: mean IOP decreased by 31% to 14.2 mmHg (p < 0.001) vs by 43% to 12.5 mmHg (p < 0.001); mean medications decreased by 51% to 1.31 medications (p < 0.001) vs by 84% to 0.43 medications (p < 0.001). Multi-Stent eyes, compared to Trab eyes, had fewer visits ± reinterventions within 3 months (3.6 vs 6.1, p < 0.001); longer time to first reintervention (12.2 months vs 4.5 months, p = 0.01); fewer total reinterventions (0.26 vs 0.75, p = 0.006); and earlier lifting of postoperative restrictions (12.6 vs 32.1 days, p < 0.001). In 2-vs-3-stent analysis, there was a trend toward more 3-stent eyes achieving target IOP than 2-stent eyes. Visual fields remained stable in both Multi-Stent and Trab eyes. CONCLUSION Implanting 2-3 trabecular micro-bypass stents was a viable alternative to trabeculectomy for moderate-to-severe OAG, with clinically appropriate IOP/medication reductions and higher safety-adjusted treatment success vs trabeculectomy.
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Affiliation(s)
- Ricardo Augusto Paletta Guedes
- Paletta Guedes Eye Institute, Juiz de Fora, Brazil.
- Federal University of Juiz de Fora, 79, Oscar Vidal Street, Juiz de Fora, MG, Brazil.
| | | | | | - Alfredo Chaoubah
- Federal University of Juiz de Fora, 79, Oscar Vidal Street, Juiz de Fora, MG, Brazil
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Singh IP, Sarkisian S, Hornbeak D, Katz LJ, Samuelson T. Treatment Success Across Different Levels of Preoperative Disease Burden: Stratified Two-Year Outcomes from the Pivotal Trial of iStent inject ® Trabecular Micro-Bypass in Primary Open-Angle Glaucoma and Cataract. Clin Ophthalmol 2021; 15:3231-3240. [PMID: 34376967 PMCID: PMC8349204 DOI: 10.2147/opth.s316270] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 06/23/2021] [Indexed: 12/28/2022] Open
Abstract
PURPOSE To examine effectiveness outcomes stratified by preoperative disease burden in the pivotal trial of iStent inject ® with cataract surgery (INJ) vs cataract surgery alone (CS). MATERIALS AND METHODS Prospective, 3:1 randomized, single-masked, concurrently-controlled, multicenter trial enrolling 505 subjects with cataract and mild-to-moderate primary open-angle glaucoma who underwent iStent inject implantation with phacoemulsification or phacoemulsification alone, and were followed for 2 years including annual medication washouts. Post hoc stratification was completed for baseline mean diurnal intraocular pressure (BL DIOP; Low-DIOP <25mmHg, Mid-DIOP ≥25 to <30 mmHg, High-DIOP ≥30mmHg) and preoperative medication burden (Low-Med 1 medication, Mid-Med 2 medications, High-Med ≥3 medications). RESULTS The 24-month primary and secondary effectiveness endpoints were met, with significant treatment-over-control differences in percent of eyes achieving ≥20% unmedicated DIOP reduction and in unmedicated DIOP reduction, respectively. In subgroup analyses, the proportions of INJ eyes achieving the primary endpoint remained steady across all BL DIOP (75.4%, 77.1%, 74.4% in Low/Mid/High-DIOP strata, respectively) and preoperative medication levels (76.8%, 70.8%, 79.7% in Low/Mid/High-Med strata, respectively); meanwhile, the proportions of CS eyes diminished with higher BL DIOP (64.5%, 63.6%, 33.3%, respectively) and more medications (69.0%, 63.3%, 29.4%, respectively). Regarding secondary effectiveness, postoperative DIOP reduction increased with higher BL DIOP in INJ eyes (6.2mmHg, 7.8mmHg, 9.8mmHg, respectively) but plateaued in CS eyes (5.2mmHg, 5.8mmHg, 5.4mmHg, respectively). INJ eyes also had consistent DIOP reduction regardless of preoperative medication burden (6.8mmHg, 6.7mmHg, 7.8mmHg, respectively), while DIOP reduction diminished with more medications in CS eyes (6.1mmHg, 5.0mmHg, 3.3mmHg, respectively). Safety was favorable, comparable to phacoemulsification alone. CONCLUSION Significant IOP reductions occurred across all levels of BL DIOP and preoperative medication burden in iStent inject eyes. DIOP reductions increased with higher BL DIOP and remained stable across all levels of preoperative medication burden, suggesting the device's potential utility in more medically challenging cases.
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Affiliation(s)
| | | | | | - L Jay Katz
- Glaukos Corporation, San Clemente, CA, USA
- Wills Eye Hospital, Philadelphia, PA, USA
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Saheb H, Donnenfeld ED, Solomon KD, Voskanyan L, Chang DF, Samuelson TW, Ahmed IIK, Katz LJ. Five-Year Outcomes Prospective Study of Two First-Generation Trabecular Micro-Bypass Stents (iStent®) in Open-Angle Glaucoma. Curr Eye Res 2020; 46:224-231. [PMID: 32715828 DOI: 10.1080/02713683.2020.1795881] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE To assess 5-year effectiveness and safety of 2 iStent® trabecular micro-bypass stents in eyes with open-angle glaucoma (OAG) not controlled on 1 medication. MATERIALS AND METHODS This prospective, interventional, single-arm, multi-surgeon study (NCT #1252862, clinicaltrials.gov) enrolled eyes with OAG, preoperative intraocular pressure (IOP) of 18-30 mmHg on 1 ocular hypotensive medication, and 22-38 mmHg after medication washout. Eyes underwent standalone implantation of 2 iStent devices and were followed through 60 months postoperatively. Efficacy was quantified by mean diurnal IOP and medication usage. Efficacy endpoints included the proportion of eyes with ≥20% IOP reduction versus baseline unmedicated IOP (primary efficacy), and the proportion of eyes with IOP ≤18 mmHg (secondary efficacy) without medication or secondary glaucoma surgery. Safety parameters included visual acuity, cup-to-disc ratio, visual field, and complications and adverse events. RESULTS Preoperative mean IOP on 1 medication was 20.6 ± 2.0 mmHg and post-washout unmedicated IOP was 24.1 ± 1.4 mmHg (n = 39). At 5 years postoperative, medication-free mean diurnal IOP reduced to 14.5 ± 2.2 mmHg, constituting a 40% decrease versus preoperative washed-out IOP (p < .0001). In addition, this 5-year medication-free IOP constituted a 30% decrease versus preoperative IOP on 1 medication (p < .0001). At Month 60, 89.7% (26/29) of eyes achieved the primary efficacy endpoint of ≥20% IOP reduction versus baseline unmedicated IOP, and 86.2% (25/29) of eyes achieved the secondary efficacy endpoint of IOP ≤18 mmHg, without medication or secondary glaucoma surgery. Throughout follow-up, 89.7-91.3% of eyes were on no medications. Favorable safety included no secondary glaucoma surgeries, minimal adverse events, and stable visual acuity, cup-to-disc ratio, and visual fields through 5 years postoperative. CONCLUSIONS This prospective interventional study demonstrates persistent 5-year reductions in IOP and freedom from medications, together with favorable safety, following implantation of 2 first-generation trabecular micro-bypass stents in eyes with OAG on 1 preoperative medication.
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Affiliation(s)
- Hady Saheb
- Department of Ophthalmology, McGill University , Montreal, Quebec, Canada
| | - Eric D Donnenfeld
- Ophthalmic Consultants of Long Island , Rockville Centre, New York, USA
| | - Kerry D Solomon
- Carolina Eyecare Physicians , Mt Pleasant, South Carolina, USA
| | | | | | | | - Iqbal Ike K Ahmed
- Department of Ophthalmology, University of Toronto , Toronto, Ontario, Canada
| | - L Jay Katz
- Department of Ophthalmology, Wills Eye Hospital, Jefferson Medical College , Philadelphia, Pennsylvania, USA
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Wang C, Dang Y, Shah P, Esfandiari H, Hong Y, Loewen RT, Waxman S, Atta S, Xia X, Loewen NA. Intraocular pressure reduction in a pigmentary glaucoma model by Goniotome Ab interno trabeculectomy. PLoS One 2020; 15:e0231360. [PMID: 32298335 PMCID: PMC7162452 DOI: 10.1371/journal.pone.0231360] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 03/21/2020] [Indexed: 01/08/2023] Open
Abstract
PURPOSE To investigate whether microsurgical excision of trabecular meshwork (TM) in an ex vivo pigmentary glaucoma model can normalize the hypertensive phenotype. METHODS Eight eyes of a porcine pigmentary glaucoma model underwent 90° of microsurgical TM excision with an aspirating dual-blade (Goniotome (G)). 24 hours later, additional 90° of TM were removed. Anterior segments with sham surgeries served as the control (C). Outflow facility and intraocular pressure (IOP) were analyzed. Histology with hematoxylin and eosin (H&E) was obtained. RESULTS After the first 90° TM excision, IOP was significantly lower in G (10.2±2.4 mmHg, n = 7) than C (20.0±2.0mmHg, n = 8, P<0.01). Outflow facility in G (0.38±0.07 μl/min/mmHg) was higher than C (0.16±0.02 μl/min/mmHg, P<0.01). After the second 90° TM excision, IOP in G (6.46±0.81 mmHg, n = 7) was significantly lower than C (20.3±1.7 mmHg, n = 8, P<0.001), while the outflow facility in G (0.50±0.05 μl/min/mmHg, n = 7) was higher than C (0.16±0.01 μl/min/mmHg, n = 8, P<0.001). Compared to the first excision, excision of an additional 90° did not change of IOP (P = 0.20) or outflow facility (P = 0.17) further. CONCLUSIONS Excision of 90° of TM in a pigmentary glaucoma model using an aspirating dual-blade decreased IOP and increased outflow facility.
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Affiliation(s)
- Chao Wang
- Department of Ophthalmology, University of Würzburg, Würzburg, Germany
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Department of Ophthalmology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Yalong Dang
- Department of Ophthalmology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Priyal Shah
- Department of Ophthalmology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Hamed Esfandiari
- Department of Ophthalmology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Ying Hong
- Department of Ophthalmology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Ralitsa T. Loewen
- Department of Ophthalmology, University of Würzburg, Würzburg, Germany
- Department of Ophthalmology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Susannah Waxman
- Department of Ophthalmology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Sarah Atta
- Department of Ophthalmology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Xiaobo Xia
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Nils A. Loewen
- Department of Ophthalmology, University of Würzburg, Würzburg, Germany
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Lindstrom R, Sarkisian SR, Lewis R, Hovanesian J, Voskanyan L. Four-Year Outcomes of Two Second-Generation Trabecular Micro-Bypass Stents in Patients with Open-Angle Glaucoma on One Medication. Clin Ophthalmol 2020; 14:71-80. [PMID: 32021070 PMCID: PMC6968820 DOI: 10.2147/opth.s235293] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Accepted: 12/17/2019] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION This study evaluated long-term reductions in intraocular pressure (IOP) and medication following implantation of 2 second-generation trabecular micro-bypass stents (iStent inject®) in eyes with open-angle glaucoma (OAG) not controlled on 1 preoperative medication. MATERIAL AND METHODS In this prospective interventional multi-surgeon study, standalone implantation of 2 iStent inject stents was performed in 57 eyes of 57 subjects with OAG, preoperative IOP of 18-30 mmHg on 1 medication, and preoperative post-washout IOP of 22-38 mmHg. The main outcome measures included the proportions of eyes achieving medication-free IOP ≤18 mmHg, IOP ≤15 mmHg, or ≥20% IOP reduction versus preoperative unmedicated IOP. Assessments included IOP, medications, visual acuity, visual field, pachymetry, complications, and interventions. Subjects were followed for 48 months with follow-up continuing in all eyes. RESULTS At Month 48 (n=57), 95% of eyes achieved an IOP reduction of ≥20% without medication versus preoperative washout IOP; and although they had eliminated medication, 81% of eyes still had an IOP reduction of ≥20% versus preoperative IOP on 1 medication. Mean 48-month unmedicated IOP decreased by 46% to 13.2±1.6 mmHg vs 24.4±1.3 mmHg preoperatively (p<0.0001), with 95% of medication-free eyes having IOP ≤18mmHg and 82% having IOP ≤15mmHg. Over the course of follow-up, 3 eyes had medication added and 1 eye underwent a secondary glaucoma surgery, and safety parameters were favorable. DISCUSSION Standalone iStent inject implantation in OAG patients on 1 preoperative medication resulted in average IOP reduction to ≤15 mmHg with the elimination of medication and favorable safety through 48 months. TRIAL REGISTRATION ClinicalTrials.gov identifier, NCT02868190.
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Affiliation(s)
| | | | | | | | - Lilit Voskanyan
- S.V. Malayan Ophthalmology Centre, Glaucoma Department, Yerevan, Armenia
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Neuhann R, Neuhann T. Second-generation trabecular micro-bypass stent implantation: Retrospective analysis after 12- and 24-month follow-up. EYE AND VISION (LONDON, ENGLAND) 2020; 7:1. [PMID: 31938714 PMCID: PMC6953161 DOI: 10.1186/s40662-019-0169-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 12/19/2019] [Indexed: 01/15/2023]
Abstract
BACKGROUND The study aimed to investigate the 24-month safety and efficacy of implantation of two second-generation iStent inject trabecular micro-bypass stents with concomitant cataract surgery. METHODS This consecutive case series included 164 eyes of 109 patients implanted with the iStent inject® device with concomitant cataract surgery. The series was comprised of eyes with primary open-angle glaucoma (n = 84), pseudoexfoliation glaucoma (n = 42), normal-tension glaucoma (n = 18), and ocular hypertension (n = 20). All 164 eyes reached 9-14 months of follow-up ("12-month consistent cohort"), with a subset of 88 eyes reaching 21-26 months of follow-up ("24-month consistent cohort"). Performance outcome measures included intraocular pressure (IOP) and number of glaucoma medications. Safety outcomes included intra- or postoperative complications, the need for secondary procedures and corrected distance visual acuity. Comparisons of change in continuous (e.g., IOP) and categorical (e.g., proportions of eyes on zero medications) measures between baseline and postoperative times were made with the paired t-test and McNemar's chi-squared test, respectively. RESULTS At 12 months postoperatively, IOP was reduced by 25.5% (from 20.0 ± 5.5 mmHg to 14.9 ± 2.0 mmHg; p < 0.001); at 24 months postoperatively, IOP was reduced by 26.6% (from 20.3 ± 6.1 mmHg to 14.9 ± 1.9 mmHg; p < 0.001). At 12 months postoperatively, mean number of glaucoma medications was reduced by 85.0% (from 2.0 ± 1.0 to 0.3 ± 0.8 medications; p < 0.001); at 24 months postoperatively, mean number of medications was reduced by 81.0% (from 2.1 ± 1.1 to 0.4 ± 0.8 medications; p < 0.001). After 12 months, 96.3% of eyes had an IOP ≤ 18 mmHg and 58.5% of eyes had an IOP ≤ 15 mmHg, with 81.1% of eyes free of any medication, compared to 1.8% of eyes medication-free in the 12-month cohort at baseline. After 24 months, 98.9% of eyes had an IOP ≤ 18 mmHg and 53.4% of eyes had an IOP ≤ 15 mmHg, with 72.7% free of medication compared to 1.1% of eyes medication-free in the 24-month cohort at baseline. Overall, a high safety profile was observed with no significant postoperative complications. CONCLUSIONS The insertion of iStent inject (comprised of two second-generation trabecular micro-bypass stents) with cataract surgery effectively provides a sustained reduction in IOP with a markedly improved medication burden up to 24 months postoperatively.
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Affiliation(s)
- Raphael Neuhann
- Ophthalmologikum Dr.Neuhann, Augentagesklinik Marienplatz, Marienplatz 18-19, 80331 Munich, Germany
| | - Tobias Neuhann
- Ophthalmologikum Dr.Neuhann, Augentagesklinik Marienplatz, Marienplatz 18-19, 80331 Munich, Germany
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Manning D. Real-world Case Series of iStent or iStent inject Trabecular Micro-Bypass Stents Combined with Cataract Surgery. Ophthalmol Ther 2019; 8:549-561. [PMID: 31422555 PMCID: PMC6858412 DOI: 10.1007/s40123-019-00208-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Indexed: 10/28/2022] Open
Abstract
INTRODUCTION This real-world retrospective case series assessed 12-month effectiveness and safety following implantation of iStent® or iStent inject® trabecular micro-bypass with cataract surgery. METHODS Consecutive patients were implanted with either iStent (comprising 1 stent) or iStent inject (comprising 2 stents), together with cataract surgery. Most patients had primary open-angle glaucoma. Effectiveness outcomes through 12 months included intraocular pressure (IOP) and glaucoma medications. Proportional analyses were completed for eyes achieving IOP ≤ 18 mmHg, IOP ≤ 15 mmHg, or IOP reduction ≥ 20% from preoperative; and eyes on 0 medications or ≥ 2 medications. Safety outcomes included adverse events, secondary surgeries, visual acuity, and visual fields. RESULTS This analysis included 137 eyes (67 iStent, 70 iStent inject) with cataract and mild to moderate glaucoma or ocular hypertension. Over 73% of eyes in both groups had early disease, and ~ 22% had prior glaucoma surgery. At 12 months postoperatively, mean IOP decreased from 18.4 ± 4.2 mmHg to 14.2 ± 2.5 mmHg in iStent eyes (p < 0.0001), and from 20.4 ± 5.6 mmHg to 14.4 ± 2.1 mmHg in iStent inject eyes (p < 0.0001). The IOP reduction was significantly greater for iStent inject eyes than iStent eyes (6.0 mmHg versus 4.2 mmHg reduction, p = 0.034). Both groups had high proportions of patients achieving the 12-month IOP endpoints, although consistently greater proportions reached these endpoints after iStent inject than iStent: 95.7% versus 92.5% had IOP ≤ 18 mmHg, respectively; 74.3% versus 71.6% had IOP ≤ 15 mmHg, respectively; and 68.6% versus 62.7% had IOP reduction ≥ 20% from baseline, respectively. Mean medication burden at 12 months decreased from 1.8 ± 0.7 to 0.3 ± 0.5 medications in iStent eyes (84.0% reduction, p < 0.0001), and from 1.3 ± 0.9 to 0.1 ± 0.3 medications in iStent inject eyes (94.7% reduction, p < 0.0001). Significantly more iStent inject eyes were medication-free at 12 months than iStent eyes (92.9% versus 76.1% medication-free, respectively; p = 0.0068). Favorable safety included few adverse events, no secondary glaucoma surgeries, and stable visual acuity and visual fields in both groups. CONCLUSION Significant and safe IOP and medication reductions were achieved through 12 months after iStent or iStent inject implantation with cataract surgery. iStent inject eyes had greater absolute IOP reduction and more eyes medication-free versus iStent eyes. FUNDING Glaukos Corporation.
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Affiliation(s)
- David Manning
- Hunter Cataract and Eye Centre, Charlestown, NSW, Australia.
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Guedes RAP, Gravina DM, Lake JC, Guedes VMP, Chaoubah A. One-Year Comparative Evaluation of iStent or iStent inject Implantation Combined with Cataract Surgery in a Single Center. Adv Ther 2019; 36:2797-2810. [PMID: 31440981 PMCID: PMC6822971 DOI: 10.1007/s12325-019-01067-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Indexed: 11/20/2022]
Abstract
INTRODUCTION This retrospective consecutive case series assessed 12-month effectiveness and safety of iStent® or iStent inject® trabecular micro-bypass implants with cataract surgery in patients with open-angle glaucoma (OAG) in a real-world clinical setting. METHODS Effectiveness outcomes consisted of intraocular pressure (IOP) reduction; glaucoma medication reduction; proportions of eyes achieving IOP < 18, < 15, or < 12 mmHg; and proportional analysis of medication usage. Safety outcomes included adverse events, secondary surgeries, and best-corrected visual acuity (BCVA). RESULTS This evaluation included 58 eyes with OAG (35 iStent, 23 iStent inject), with 96.6% of eyes having mild or moderate glaucoma. Diagnoses included primary open-angle glaucoma (the majority; 72.4%), pseudoexfoliative glaucoma, and pigmentary glaucoma. Baseline mean IOP and medications were statistically comparable between groups: 16.1 ± 3.6 mmHg on a mean of 1.8 ± 0.8 medications in the iStent group, and 16.2 ± 3.1 mmHg on a mean of 1.7 ± 0.8 medications in the iStent inject group. Twelve months after stent-cataract surgery, mean IOP was significantly lower in the iStent inject group than in the iStent group (13.1 mmHg vs. 15.4 mmHg, respectively; p < 0.001), and the percent reduction in IOP from baseline was significantly greater in iStent inject eyes than in iStent eyes (19.1% vs. 4.3% reduction, respectively; p < 0.001). At 12 months postoperative, significantly greater proportions of iStent inject eyes than iStent eyes achieved IOP < 18 mmHg (100% vs. 80.0% of eyes, respectively; p = 0.035), IOP < 15 mmHg (73.9% vs. 34.3% of eyes, respectively; p = 0.003), and IOP < 12 mmHg (26.1% vs. 0% of eyes, respectively; p = 0.002). Meanwhile, both groups achieved significant medication reductions at 12 months vs. baseline (94.1% reduction in iStent inject eyes, p < 0.0001; and 72.2% reduction in iStent eyes, p < 0.0001), with the percent reduction being significantly greater in iStent inject eyes than in iStent eyes (p = 0.023). At 12 months, mean number of medications was significantly lower in iStent inject eyes than iStent eyes (0.1 vs. 0.5 medications, respectively; p = 0.021), and significantly more iStent inject eyes (95.7%) than iStent eyes (71.4%) were off medications entirely (p = 0.021). A similarly high safety profile was observed in both groups. CONCLUSION iStent or iStent inject implantation with cataract surgery resulted in substantial and safe reductions in IOP and medications through 12 months postoperative. Consistent with prior observations, greater efficacy was observed with iStent inject than with iStent. FUNDING The Rapid Service Fees were funded by Glaukos Corporation.
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Affiliation(s)
- Ricardo Augusto Paletta Guedes
- Paletta Guedes Eye Institute, Juiz de Fora, Minas Gerais, Brazil.
- Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil.
| | | | | | | | - Alfredo Chaoubah
- Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
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Guedes RAP, Gravina DM, Lake JC, Guedes VMP, Chaoubah A. Intermediate Results of iStent or iStent inject Implantation Combined with Cataract Surgery in a Real-World Setting: A Longitudinal Retrospective Study. Ophthalmol Ther 2019; 8:87-100. [PMID: 30721523 PMCID: PMC6393257 DOI: 10.1007/s40123-019-0166-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Indexed: 11/02/2022] Open
Abstract
INTRODUCTION In this real-world, retrospective, comparative study we evaluated 6-month performance and safety in consecutive eyes following implantation of the iStent® or iStent inject® trabecular micro-bypass device with concomitant cataract surgery. METHODS Performance outcomes included intraocular pressure (IOP) reduction; glaucoma medication reduction; proportions of eyes achieving an IOP of < 18, < 16, < 14, or < 12 mmHg; and proportions of eyes on 0, 1, 2, or ≥ 3 medications. Safety outcomes included adverse events, secondary surgeries, and best-corrected visual acuity (BCVA). RESULTS A total of 73 eyes with open-angle glaucoma and cataract were included in the study; of these, 38 eyes were implanted with the iStent device and 35 were implanted with the iStent inject device. The two groups of patients had similar baseline characteristics, with the exception of mean age and medication burden (both higher in patients receiving the iStent inject device); over 90% of eyes in both groups had early glaucoma. At 6 months after surgery, mean IOP had fallen from 16.5 ± 3.9 to 13.9 ± 2.3 mmHg in eyes with the iStent implant (p < 0.001), and from 17.3 ± 3.0 to 12.7 ± 1.8 mmHg in those with the iStent inject implant (p < 0.001). This reduction was significantly greater in the iStent inject eyes than in the iStent eyes (26.6 vs. 15.8%) (p = 0.005). Significantly more eyes receiving the iStent inject device compared to the iStent device achieved an IOP of < 18 mmHg at 6 months post surgery (100 vs. 86.8%) (p = 0.033). Average medication usage was reduced from 1.8 to 0.4 medications in iStent eyes (p < 0.001) and from 2.3 to 0.4 medications in iStent inject eyes (p < 0.001). Over 70% of eyes in both groups became medication-free by 6 months post implantation. Adverse events in iStent eyes were mild and resulted in no sequelae; two iStent eyes underwent non-penetrating deep sclerectomy during follow-up. No complications or secondary surgeries were noted in iStent inject eyes. All eyes in both groups maintained or showed improved BCVA versus baseline. CONCLUSION Significant and safe IOP and medication reductions were observed after iStent or iStent inject implantation with concomitant cataract surgery. Trends toward greater effectiveness and fewer adverse events were observed with the iStent inject device compared with the iStent device. FUNDING Article processing charges were provided by Glaukos Corporation.
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Affiliation(s)
| | | | - Jonathan Clive Lake
- Cataract and Glaucoma Department, Brasilia Vision Hospital, Brasilia, DF, Brazil
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Abstract
SIGNIFICANCE Noncompliance is a problem affecting glaucoma patients. Approaches to improve adherence include the use of drug-delivery systems and safer forms of surgery. Minimally invasive glaucoma surgery (MIGS) has reduced complications, particularly in combination with cataract surgery, and with its good intraocular pressure (IOP) reduction may reduce or eliminate glaucoma medications.Glaucoma is a progressive disease and a leading cause of irreversible blindness. Elevated IOP is the most important risk factor, but effective medical management is dependent on patient adherence. This review summarizes the adherence problem in glaucoma and the efforts, including MIGS, to provide effective IOP control that is not dependent on patient compliance.The current understanding of patient adherence to pharmacological treatment of glaucoma is discussed including the challenges facing glaucoma patients. Historical approaches to providing IOP control in a sustained and reliable way are presented culminating in a review of the burgeoning use of MIGS devices.It is estimated that, in the United States, 27% of prescriptions written, across all medications, are not filled or are filled but not taken. For ocular hypotensive medications, even when filled, a large percentage (which varies widely by study) are not instilled as prescribed. To address this problem, methods for sustained drug delivery have been and continue to be developed, as well as surgical and laser approaches. Most recently, MIGS devices have gained popularity because of the ease of implantation during cataract surgery, favorable safety profile, and the possibility for effective and long-lasting IOP lowering, as well as the reduction or elimination of need for IOP-lowering medication.Poor adherence to treatment is relatively common among glaucoma patients and is associated with progression of disease. Recommending MIGS implantation during cataract surgery may offer optometrists a valuable treatment option in managing glaucoma patients, particularly where good adherence is in doubt.
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Dang Y, Wang C, Shah P, Waxman S, Loewen RT, Hong Y, Esfandiari H, Loewen NA. Outflow enhancement by three different ab interno trabeculectomy procedures in a porcine anterior segment model. Graefes Arch Clin Exp Ophthalmol 2018; 256:1305-1312. [PMID: 29721662 PMCID: PMC7804591 DOI: 10.1007/s00417-018-3990-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/29/2018] [Accepted: 04/11/2018] [Indexed: 12/11/2022] Open
Abstract
PURPOSE To evaluate three different microincisional ab interno trabeculectomy procedures in a porcine eye perfusion model. METHODS In perfused porcine anterior segments, 90° of trabecular meshwork (TM) was ablated using the Trabectome (T; n = 8), Goniotome (G; n = 8), or Kahook device (K; n = 8). After 24 h, additional 90° of TM was removed. Intraocular pressure (IOP) and outflow facility were measured at 5 and 10 μl/min perfusion to simulate an elevated IOP. Structure and function were assessed with canalograms and histology. RESULTS At 5 μl/min infusion rate, T resulted in a greater IOP reduction than G or K from baseline (76.12% decrease versus 48.19% and 47.96%, P = 0.013). IOP reduction between G and K was similar (P = 0.420). Removing another 90° of TM caused an additional IOP reduction only in T and G but not in K. Similarly, T resulted in the largest increase in outflow facility at 5 μl/min compared with G and K (first ablation, 3.41 times increase versus 1.95 and 1.87; second ablation, 4.60 versus 2.50 and 1.74) with similar results at 10 μl/min (first ablation, 3.28 versus 2.29 and 1.90 (P = 0.001); second ablation, 4.10 versus 3.01 and 2.01 (P = 0.001)). Canalograms indicated circumferential flow beyond the ablation endpoints. CONCLUSIONS T, G, and K significantly increased the outflow facility. In this model, T had a larger effect than G and K.
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Affiliation(s)
- Yalong Dang
- Department of Ophthalmology, University of Pittsburgh School of Medicine, 203 Lothrop St, Suite 819, Pittsburgh, PA, 15213, USA
| | - Chao Wang
- Department of Ophthalmology, University of Pittsburgh School of Medicine, 203 Lothrop St, Suite 819, Pittsburgh, PA, 15213, USA
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Priyal Shah
- Department of Ophthalmology, University of Pittsburgh School of Medicine, 203 Lothrop St, Suite 819, Pittsburgh, PA, 15213, USA
- Institute of Ophthalmology and Visual Science, Rutgers New Jersey Medical School, Newark, NJ, USA
| | - Susannah Waxman
- Department of Ophthalmology, University of Pittsburgh School of Medicine, 203 Lothrop St, Suite 819, Pittsburgh, PA, 15213, USA
| | - Ralitsa T Loewen
- Department of Ophthalmology, University of Pittsburgh School of Medicine, 203 Lothrop St, Suite 819, Pittsburgh, PA, 15213, USA
| | - Ying Hong
- Department of Ophthalmology, University of Pittsburgh School of Medicine, 203 Lothrop St, Suite 819, Pittsburgh, PA, 15213, USA
| | - Hamed Esfandiari
- Department of Ophthalmology, University of Pittsburgh School of Medicine, 203 Lothrop St, Suite 819, Pittsburgh, PA, 15213, USA
| | - Nils A Loewen
- Department of Ophthalmology, University of Pittsburgh School of Medicine, 203 Lothrop St, Suite 819, Pittsburgh, PA, 15213, USA.
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Katz LJ, Erb C, Carceller Guillamet A, Fea AM, Voskanyan L, Giamporcaro JE, Hornbeak DM. Long-term titrated IOP control with one, two, or three trabecular micro-bypass stents in open-angle glaucoma subjects on topical hypotensive medication: 42-month outcomes. Clin Ophthalmol 2018; 12:255-262. [PMID: 29440867 PMCID: PMC5798569 DOI: 10.2147/opth.s152268] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose Evaluate long-term outcomes after one, two, or three trabecular micro-bypass stents implanted in a standalone procedure in eyes with open-angle glaucoma taking ocular hypotensive medication. Patients and methods Prospective randomized ongoing study of 119 subjects (109 with 42-month follow-up) with open-angle glaucoma, preoperative intraocular pressure (IOP) 18-30 mmHg on one to three glaucoma medications, and unmedicated (post-washout) IOP 22-38 mmHg. Subjects were randomized to receive one (n=38), two (n=41), or three (n=40) iStent trabecular micro-bypass stents in a standalone procedure. Postoperatively, IOP was measured with medication and annually following washout. Data included IOP, medications, gonioscopy, pachymetry, visual field, visual acuity, adverse events, and slit-lamp and fundus examinations. Results Preoperative mean medicated IOP was 19.8±1.3 mmHg on 1.71 medications in one-stent eyes, 20.1±1.6 mmHg on 1.76 medications in two-stent eyes, and 20.4±1.8 mmHg on 1.53 medications in three-stent eyes. Post-washout IOP prior to stent implantation was 25.0±1.2, 25.0±1.7, and 25.1±1.9 mmHg in the three groups, respectively. Postoperatively, Month 42 medicated IOP was 15.0±2.8, 15.7±1.0 and 14.8±1.3 mmHg in the three groups, and post-washout IOP (Months 36-37) was 17.4±0.9, 15.8±1.1 and 14.2±1.5 mmHg, respectively. IOP reduction ≥20% without medication was achieved in 89%, 90%, and 92% of one-, two-, and three-stent eyes, respectively, at Month 12; and in 61%, 91%, and 91% of eyes, respectively, at Month 42. The need for additional medication remained consistent at Months 12 and 42 in multi-stent eyes (four two-stent eyes and three three-stent eyes at both time points), whereas it increased in single-stent eyes (four eyes at Month 12 versus 18 eyes at Month 42). Safety parameters were favorable in all groups. Conclusion The standalone implantation of either single or multiple iStent® device(s) produced safe, clinically meaningful IOP and medication reductions through 42 months postoperatively, with incrementally greater and more sustained reductions in multi-stent eyes.
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Affiliation(s)
- L Jay Katz
- Glaucoma Service, Wills Eye Hospital, Philadelphia, PA, USA
| | - Carl Erb
- Glaucoma Service, Eye Clinic Wittenbergplatz, Berlin, Germany
| | | | - Antonio M Fea
- Department of Surgical Sciences, University of Torino, Torino, Italy
| | - Lilit Voskanyan
- Glaucoma Service, S. V. Malayan Ophthalmology Centre, Yerevan, Armenia
| | - Jane Ellen Giamporcaro
- Department of Clinical Research and Medical Affairs, Glaukos Corporation, San Clemente, CA, USA
| | - Dana M Hornbeak
- Department of Clinical Research and Medical Affairs, Glaukos Corporation, San Clemente, CA, USA
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Loewen RT, Brown EN, Scott G, Parikh H, Schuman JS, Loewen NA. Quantification of Focal Outflow Enhancement Using Differential Canalograms. Invest Ophthalmol Vis Sci 2017; 57:2831-8. [PMID: 27227352 PMCID: PMC5113980 DOI: 10.1167/iovs.16-19541] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To quantify regional changes of conventional outflow caused by ab interno trabeculectomy (AIT). Methods Gonioscopic, plasma-mediated AIT was established in enucleated pig eyes. We developed a program to automatically quantify outflow changes (R, package eye-canalogram, github.com) using a fluorescent tracer reperfusion technique. Trabecular meshwork (TM) ablation was demonstrated with fluorescent spheres in six eyes before formal outflow quantification with two-dye reperfusion canalograms in six additional eyes. Eyes were perfused with a central, intracameral needle at 15 mm Hg. Canalograms and histology were correlated for each eye. Results The pig eye provided a model with high similarity to AIT in human patients. Histology indicated ablation of TM and unroofing of most Schlemm's canal segments. Spheres highlighted additional circumferential and radial outflow beyond the immediate area of ablation. Differential canalograms showed that AIT caused an increase of outflow of 17 ± 5-fold inferonasally, 14 ± 3-fold superonasally, and also an increase in the opposite quadrants with a 2 ± 1-fold increase superotemporally, and 3 ± 3 inferotemporally. Perilimbal specific flow image analysis showed an accelerated nasal filling with an additional perilimbal flow direction into adjacent quadrants. Conclusions A quantitative, differential canalography technique was developed that allows us to quantify supraphysiological outflow enhancement by AIT.
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Affiliation(s)
- Ralitsa T Loewen
- Department of Ophthalmology University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States
| | - Eric N Brown
- Department of Ophthalmology, Vanderbilt University School of Medicine, Nashville, Tennessee, United States
| | - Gordon Scott
- Department of Ophthalmology University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States
| | - Hardik Parikh
- Department of Ophthalmology University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States 3School of Medicine, Rutgers State University of New Jersey, New Brunswick, New Jersey, United States
| | - Joel S Schuman
- Department of Ophthalmology University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States 4School of Medicine, New York University, New York, New York, United States
| | - Nils A Loewen
- Department of Ophthalmology University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States
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Schehlein EM, Kaleem MA, Swamy R, Saeedi OJ. Microinvasive Glaucoma Surgery: An Evidence-Based Assessment. EXPERT REVIEW OF OPHTHALMOLOGY 2017; 12:331-343. [PMID: 30026790 DOI: 10.1080/17469899.2017.1335597] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Introduction The advent of Microinvasive Glaucoma Surgery (MIGS) offers a novel approach in the treatment of glaucoma with the number of procedures developing at an exciting pace. Areas Covered MIGS procedures aim to lower intraocular pressure (IOP) via four mechanisms: (1) increasing trabecular outflow, (2) increasing outflow via suprachoroidal shunts, (3) reducing aqueous production, and (4) subconjunctival filtration. A comprehensive search for published studies for each Microinvasive Glaucoma Surgery (MIGS) device or procedure was undertaken using the electronic database PubMed. Search terms included 'minimally invasive glaucoma surgery', 'microincisional glaucoma surgery', and 'microinvasive glaucoma surgery'. A manual search for each device or procedure was also performed. After review, randomized control trials and prospective studies were preferentially included. Expert Opinion These procedures offer several benefits: an improved safety profile allowing for intervention in earlier stages of glaucoma, combination with cataract surgery, and decreased dependence on patient compliance with topical agents. Established MIGS procedures have proven efficacy and more recent devices and procedures show promising results. Despite this, further study is needed to assess the long term IOP-lowering effectiveness of these procedures. Particularly, rigorous study with more randomized control trials and head-to-head comparisons would allow for better informed clinical and surgical decision-making. MIGS offers new solutions for glaucoma treatment.
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Affiliation(s)
- Emily M Schehlein
- University of Maryland School of Medicine, Department of Ophthalmology and Visual Sciences, 419 W Redwood Street, Suite 420, Baltimore, MD 21201
| | - Mona A Kaleem
- University of Maryland School of Medicine, Department of Ophthalmology and Visual Sciences, 419 W Redwood Street, Suite 420, Baltimore, MD 21201
| | - Ramya Swamy
- University of Maryland School of Medicine, Department of Ophthalmology and Visual Sciences, 419 W Redwood Street, Suite 420, Baltimore, MD 21201
| | - Osamah J Saeedi
- University of Maryland School of Medicine, Department of Ophthalmology and Visual Sciences, 419 W Redwood Street, Suite 420, Baltimore, MD 21201
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Richter GM, Coleman AL. Minimally invasive glaucoma surgery: current status and future prospects. Clin Ophthalmol 2016; 10:189-206. [PMID: 26869753 PMCID: PMC4734795 DOI: 10.2147/opth.s80490] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Minimally invasive glaucoma surgery aims to provide a medication-sparing, conjunctival-sparing, ab interno approach to intraocular pressure reduction for patients with mild-to-moderate glaucoma that is safer than traditional incisional glaucoma surgery. The current approaches include: increasing trabecular outflow (Trabectome, iStent, Hydrus stent, gonioscopy-assisted transluminal trabeculotomy, excimer laser trabeculotomy); suprachoroidal shunts (Cypass micro-stent); reducing aqueous production (endocyclophotocoagulation); and subconjunctival filtration (XEN gel stent). The data on each surgical procedure for each of these approaches are reviewed in this article, patient selection pearls learned to date are discussed, and expectations for the future are examined.
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Affiliation(s)
- Grace M Richter
- UCLA Stein Eye Institute, Department of Ophthalmology, University of California, Los Angeles, CA, USA; USC Eye Institute, Department of Ophthalmology, Keck School of Medicine of University of Southern California, Los Angeles, CA, USA
| | - Anne L Coleman
- UCLA Stein Eye Institute, Department of Ophthalmology, University of California, Los Angeles, CA, USA
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Petrov SY, Vostrukhin SV, Aslamazova AE, Sherstneva LV. [Modern methods of minimally invasive glaucoma surgery]. Vestn Oftalmol 2016. [PMID: 28635828 DOI: 10.17116/oftalma2016132396-102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Over the years, glaucoma surgery has improved from iridectomy by A. Graefe and traumatizing procedures performed without magnification tools or microsurgical instrument to high-technology interventions that are not only microscopic, but also pathogenetically oriented. Various modifications of trabeculectomy, initially introduced by J. Cairns back in 1968, had been the gold standard for several decades and were notable for pronounced and stable hypotensive effects. However, there was also a strong association with such complications as choroidal detachment and hyphema, thus, boosting the development of so called nonfistulizing surgeries. Of the latter, the most widely used are non-penetrating procedures, including deep sclerectomy and viscocanalostomy. Although very safe, they appear unable to produce a truly long-lasting hypotensive effect. Moreover, just as fistulizing trabeculectomy, non-penetrating procedures damage the limbus and adjacent conjunctiva reducing the possibility of a second intervention. This fact together with other drawbacks mentioned above, on the one hand, and technical progress, on the other, were essential prerequisites for the appearance of a new type of surgery - minimally invasive glaucoma surgery (MIGS). Parameters that should be met for a procedure to be considered minimally invasive are debated. The main requirement has, however, been established: ab interno approach through a corneal incision. As surgical tools are enhanced and new techniques arise, options for glaucoma treatment widen greatly, ensuring our future move to higher level standards in the field. This review contains all recent data on minimally invasive techniques currently in use in glaucoma surgery or those under investigation. The authors have also analyzed effectiveness reports and present their conclusions regarding the current state of MIGS worldwide.
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Affiliation(s)
- S Yu Petrov
- Research Institute of Eye Diseases, 11 A, B Rossolimo St., Moscow, Russian Federation, 119021
| | - S V Vostrukhin
- Research Institute of Eye Diseases, 11 A, B Rossolimo St., Moscow, Russian Federation, 119021
| | - A E Aslamazova
- I.M. Sechenov First Moscow State Medical University, Ophthalmology Department, 8-2 Trubetskaya St., Moscow, Russian Federation, 119991
| | - L V Sherstneva
- I.M. Sechenov First Moscow State Medical University, Ophthalmology Department, 8-2 Trubetskaya St., Moscow, Russian Federation, 119991
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Katz LJ, Erb C, Carceller GA, Fea AM, Voskanyan L, Wells JM, Giamporcaro JE. Prospective, randomized study of one, two, or three trabecular bypass stents in open-angle glaucoma subjects on topical hypotensive medication. Clin Ophthalmol 2015; 9:2313-20. [PMID: 26715834 PMCID: PMC4686332 DOI: 10.2147/opth.s96695] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To assess the safety and efficacy of one, two, or three trabecular microbypass stents in eyes with primary open-angle glaucoma (OAG) not controlled on ocular hypotensive medication. A total of 119 subjects were followed for 18 months postoperatively. MATERIALS AND METHODS Subjects with medicated intraocular pressure (IOP) 18-30 mmHg and postmedication-washout baseline IOP 22-38 mmHg were randomized to implantation of one, two, or three stents. Ocular hypotensive medication was to be used if postoperative IOP exceeded 18 mmHg. RESULTS A total of 38 subjects were implanted with one stent, 41 subjects with two stents, and 40 subjects with three stents. Both month 12 IOP reduction ≥20% without ocular hypotensive medication vs baseline unmedicated IOP and month 12 unmedicated IOP ≤18 mmHg were achieved by 89.2%, 90.2%, and 92.1% of one-, two-, and three-stent eyes, respectively. Furthermore, 64.9%, 85.4%, and 92.1% of the three respective groups achieved unmedicated IOP ≤15 mmHg. Over the 18-month follow-up period, medication was required in seven one-stent subjects, four two-stent subjects, and three three-stent subjects. At 18 months, mean unmedicated IOP was 15.9±0.9 mmHg in one-stent subjects, 14.1±1.0 mmHg in two-stent subjects, and 12.2±1.1 mmHg in three-stent subjects. Month 18 IOP reduction was significantly greater (P<0.001) with implantation of each additional stent, with mean differences in reduction of 1.84 mmHg (95% confidence interval 0.96-2.73) for three-stent vs two-stent groups and 1.73 mmHg (95% confidence interval 0.83-2.64) for two-stent vs one-stent groups. Adverse events through 18 months were limited to cataract progression with best-corrected visual acuity loss and subsequent cataract surgery. CONCLUSION In this series, implantation of each additional stent resulted in significantly greater IOP reduction with reduced medication use. Titratability of stents as a sole procedure was shown to be effective and safe, with sustained effect through 18 months postoperatively in OAG not controlled with medication.
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Affiliation(s)
- L Jay Katz
- Wills Eye Hospital, Jefferson Medical College, Philadelphia, PA, USA
| | - Carl Erb
- Eye Clinic Wittenbergplatz, Berlin, Germany
| | | | - Antonio M Fea
- University Eye Clinic of the University of Turin, Turin, Italy
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Craven ER. Trabecular micro-bypass shunt (iStent®): basic science, clinical, and future). Middle East Afr J Ophthalmol 2015; 22:30-7. [PMID: 25624671 PMCID: PMC4302474 DOI: 10.4103/0974-9233.148346] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The trabecular bypass stent offers an alternative to filtration surgery. Patients who may be ideal candidates for considering this procedure are those with prior conjunctival surgery; for example, those who had a 360° peritomy from a scleral buckle might not do well with a trabeculectomy and there is no space for a tube. Highly myopic patients do not tolerate hypotony well, and the iSTB may be an option for some of these patients. I have used the iSTB in patients on anticoagulants who could not stop them, and they needed something beyond medications and laser to lower the IOP in subjects with open-angle glaucoma. Young patients, especially those with one eye, who need rapid visual recovery (for instance to return to work) may be good candidates to consider the iSTB as well. Because of the position used for clear corneal cataract surgery, the temporal approach is best for doing these. Therefore, if you are doing cataract surgery on someone who needs a lower IOP, you already are in the correct position to implant the devices. Patients may need some medications after the procedure to lower the IOP to the level desired. The results from Armenia are encouraging, given an IOP of 11.8 mmHg after 2 iSTB stents and taking daily travoprost. These results are difficult to reach even with a trabeculectomy. When selecting your fist patients, avoid those with the congested episcleral veins, look for patients with wide open angles, and if you can see aqueous veins at the slit-lamp it may indicate a viable outflow system. Probably avoid patients with IOPs over 35 mmHg. The micro-invasive trabecular bypass stents offer an alternative surgical intervention for select patients with open-angle glaucoma. Recent studies show that combining these micro-stents with medications can lead to as low of an intraocular pressure (IOP) as is achieved by many more invasive incisional surgeries. The technique is quite precise and learning the procedure is similar to clear corneal phacoemulsification followed by a goniotomy. Long-term data are starting to come in and the safety is favorable. The IOP success appears to be based on the patency of the outflow system for a given patient. Key factors in determining the success involve the placement of trabecular bypass devices into the canal of Schlemm and require a down-stream patency of the collector channel system and a low episcleral venous pressure. Because accessing the collector system may require placement by a patent channel, the placement of two stents, a longer stent with scaffolding or somehow imaging the outflow system may lead to the best control of the IOP.
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Affiliation(s)
- E Randy Craven
- Glaucma Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
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Abstract
Trabecular micro-bypass stents, commonly known as iStents, are micro-invasive glaucoma surgery (MIGS) devices used to treat open-angle glaucoma. Like other MIGS procedures that enhance trabecular outflow, the iStent lowers intraocular pressure (IOP) by creating a direct channel between the anterior chamber and Schlemm’s canal. iStents are typically implanted at the time of phacoemulsification for patients with open-angle glaucoma and visually significant cataracts. This review summarizes the published data regarding the efficacy, safety, and cost considerations of trabecular micro-bypass stents. Most studies found statistically significant reductions in mean IOP and ocular medication use after combined phacoemulsification with single or double iStent implantation. The devices were found to be very safe, with a safety profile similar to that of cataract surgery. Complications were infrequent, with the most common complications being temporary stent obstruction or malposition, which resolved with observation or secondary procedures. Future studies are needed to evaluate long-term outcomes, patient satisfaction, cost effectiveness, and expanded indications.
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Affiliation(s)
- Kim Le
- Department of Ophthalmology, McGill University, Montreal, QC, Canada
| | - Hady Saheb
- Department of Ophthalmology, McGill University, Montreal, QC, Canada
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