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Chan W, Zhang C, Mittal A, Fink A, Michalovic S, Weiner A. Effect of Preoperative Trabecular Meshwork Pigmentation and Other Eye Characteristics on Outcomes of Combined Phacoemulsification/Minimally Invasive Glaucoma Surgery. Ophthalmol Glaucoma 2024; 7:271-281. [PMID: 38185378 DOI: 10.1016/j.ogla.2024.01.001] [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: 09/16/2023] [Revised: 12/15/2023] [Accepted: 01/03/2024] [Indexed: 01/09/2024]
Abstract
PURPOSE To investigate associations between pigmentation of the trabecular meshwork (PTM) and other preoperative eye characteristics and outcomes of minimally invasive glaucoma surgery combined with phacoemulsification (Phaco/MIGS). DESIGN Retrospective interventional case series. PARTICIPANTS Academic glaucoma clinic patients with symptomatic cataract and glaucoma treated with combined Phaco/MIGS. METHODS Analyzing preoperative PTM, intraocular pressure (IOP), IOP-lowering medications and visual acuity (VA) data in relation to Phaco/MIGS outcomes. MAIN OUTCOME MEASURES Pigmentation of the trabecular meshwork and other preoperative eye characteristics in relation to Phaco/MIGS success defined as postoperative IOP between 5 and 21 mmHg and IOP reduction of ≥ 20% and/or a reduction of ≥ 1 IOP-medications compared to baseline, and final IOP, IOP-lowering medications and VA. RESULTS A total of 265 eyes (172 patients, mean age, 73.5 [standard deviation, 10.0], range 35-95 years, male 40.0%) were identified and categorized with high PTM (108 eyes, 40.8%) or low PTM (157 eyes, 59.2%). The high PTM group, compared with the low PTM group, demonstrated higher preoperative IOP (16.7 [standard error 0.4] vs. 15.2 [0.4] mmHg, P = 0.009), included more eyes with primary open-angle glaucoma (POAG, P = 0.03), fewer eyes with normal-tension glaucoma (NTG, P = 0.01), and fewer eyes with mild stage glaucoma (P = 0.001). Compared to baseline, final IOP decreased by 6.5 [2.4]% and 13.4 [3.0]% (P = 0.075) to 13.5 [0.3] mmHg and 13.6 [0.4] mmHg (P = 0.77) in the low and high PTM groups, respectively, and IOP-lowering medications decreased by 34.6 [4.9]% (n = 116) and 18.1 [7.3]% (n = 85), respectively (P = 0.062). Surgical success was 59.9% and 58.3%, respectively (P = 0.87). It was positively associated with higher preoperative IOP (hazard ratio 1.08 [95% confidence interval 1.04-1.12] P < 0.0001) and higher number of preoperative IOP-medications (1.20 [1.05-1.37] P = 0.007), negatively associated with history of selective laser trabeculoplasty (SLT, 0.40 [0.23-0.68] P = 0.0009) and longer axial length (0.87 [0.80-0.94], P = 0.0006), but was not associated with PTM. CONCLUSIONS Higher PTM was associated with POAG rather than NTG, with more severe glaucoma and higher preoperative IOP, but not with Phaco/MIGS success. Surgical success was positively associated with higher preoperative IOP and number of IOP-medications and negatively associated with history of SLT and longer axial length. These findings may help guide glaucoma surgeons in surgical planning and patient counseling. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.
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Affiliation(s)
- Weilin Chan
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo/State University of New York (SUNY), Buffalo, New York
| | - Charles Zhang
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo/State University of New York (SUNY), Buffalo, New York
| | - Abhiniti Mittal
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo/State University of New York (SUNY), Buffalo, New York
| | - Andrew Fink
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo/State University of New York (SUNY), Buffalo, New York
| | - Sharon Michalovic
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo/State University of New York (SUNY), Buffalo, New York
| | - Asher Weiner
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo/State University of New York (SUNY), Buffalo, New York.
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Yamagishi-Kimura R, Honjo M, Aihara M. Effect of a fixed combination of ripasudil and brimonidine on aqueous humor dynamics in mice. Sci Rep 2024; 14:7861. [PMID: 38570526 PMCID: PMC10991514 DOI: 10.1038/s41598-024-58212-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 03/26/2024] [Indexed: 04/05/2024] Open
Abstract
Ripasudil-brimonidine fixed-dose combination (K-232) simultaneously targets three different intraocular pressure (IOP) lowering mechanisms, increasing trabecular meshwork outflow and uveoscleral outflow, and reducing aqueous humor production Vascularly, ripasudil induces transient vasodilation, brimonidine transient vasoconstriction. Investigating effects on IOP, aqueous dynamics, and EVP in mice eyes by microneedle and constant-pressure perfusion methods, and on cytoskeletal and fibrotic proteins changes in HTM cells by a gel contraction assay and immunocytochemistry. Ripasudil, K-232, and brimonidine droplets significantly reduced IOP at 30 min, with K-232 sustaining the effect at 60 min. For EVP, only K-232 exhibited reduced EVP until 60 min after instillation. In vitro, ripasudil inhibited gel contractility and TGFβ2-induced fibrotic changes, whereas brimonidine did not. K-232 significantly lowered IOPs in mice by combining the effects of ripasudil and brimonidine. Brimonidine alone also showed IOP reductions with enhanced outflow facility, and the drug did not interfere with the effects of ripasudil on the trabecular meshwork outflow; K-232 and ripasudil alone both significantly lowered the EVP and enhanced outflow facility, demonstrating that K-232 efficiently reduces IOPs.
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Affiliation(s)
- Reiko Yamagishi-Kimura
- Department of Ophthalmology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 1138655, Japan
| | - Megumi Honjo
- Department of Ophthalmology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 1138655, Japan.
| | - Makoto Aihara
- Department of Ophthalmology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 1138655, Japan
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Irie A, Nakashima KI, Inoue T, Kojima S, Takihara Y, Takahashi E. Trabeculotomy Using the Kahook Dual Blade for Exfoliation Glaucoma and Primary Open Angle Glaucoma: Comparison of Outcomes According to Incision Range. J Glaucoma 2024; 33:270-276. [PMID: 38506849 DOI: 10.1097/ijg.0000000000002323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Accepted: 10/09/2023] [Indexed: 03/21/2024]
Abstract
PRCIS Large amount of trabeculotomy with Kahook Dual Blade (KDB) confers better intraocular pressure (IOP) lowering. PURPOSE We compared the postoperative outcomes of trabeculotomy using the KDB in patients with exfoliation glaucoma (EXG) and primary open angle glaucoma between the 120-degree incision and the 210- to 240-degree incision groups. PATIENTS AND METHODS We retrospectively analyzed the postoperative outcomes of trabeculotomy performed using the KDB in 101 eyes with EXG and primary open angle glaucoma, who received 120- and 210- to 240-degree incisions at Kumamoto University Hospital between April 25, 2018, and August 11, 2021. Kaplan-Meyer survival curves were used to assess the outcomes. Surgical failure was defined as IOP ≥21 mm Hg (criterion A) and ≥19 mm Hg (criterion B), or an IOP ≤4 mm Hg in either criterion and the need for additional glaucoma surgery. RESULTS In total, 64 and 37 eyes were included in the 120 and 210- to 240-degree groups, respectively. The 210- to 240-degree group had a higher 1-year success rate compared with the 120-degree group, both when considering all eyes and when considering only those with EXG (P<0.05). CONCLUSIONS In trabeculotomy with KDB, a 210- to 240-degree incision was more effective than a 120-degree incision in lowering IOP in EXG cases.
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Affiliation(s)
- Anna Irie
- Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | | | - Toshihiro Inoue
- Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Sachi Kojima
- Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Yuji Takihara
- Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Eri Takahashi
- Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
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Maheshwari D, Grover DS, Ramakrishnan R, Pillai MR, Chautani D, Kader MA. Early Outcomes of Combined Phacoemulsification and Ab Interno Tanito Microhook Trabeculotomy in Open-Angle Glaucoma. Ophthalmol Glaucoma 2024; 7:123-130. [PMID: 37839794 DOI: 10.1016/j.ogla.2023.10.007] [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: 05/03/2023] [Revised: 10/01/2023] [Accepted: 10/03/2023] [Indexed: 10/17/2023]
Abstract
PURPOSE To study the early postoperative efficacy and safety of an Ab Interno microhook trabeculotomy (microLOT) combined with cataract surgery in patients with open-angle glaucoma. METHODS This prospective, randomized, interventional study was conducted on consecutive patients with visually significant cataract and mild-moderate open-angle glaucoma. One hundred fourteen patients were included for analysis. The patients were randomized to undergo microhook trabeculotomy with phacoemulsification (group 1) or phacoemulsification alone (group 2). All patients were evaluated on postoperative day 1, 15, and 30, as well as 3, 6, and 12 months postoperatively. A P value < 0.05 was considered statistically significant. Baseline and follow-up visits were compared to determine significant differences in the number of antiglaucoma medications (AGMs), intraocular pressure (IOP), and best-corrected visual acuity. RESULTS There were 57 patients in each group. The baseline characteristics were similar between the 2 groups, except the number of AGMs, which was greater in group 2. The mean preoperative IOP for group 1 (phaco-microLOT) was 26.5 mmHg ± 5.2 and group 2 (phaco-alone group) was 25.3 mmHg ± 3.1 which decreased to 12.5 mmHg ±3.6 (P < 0.001) and 20.0 mmHg ± 2.7(P < 0.001) at 12 months, respectively. Logarithm of the minimum angle of resolution visual acuity improved from 0.48 (interquartile range [IQR], 0.30-0.60) preoperatively to 0.00 (0.00-0.18) postoperatively (P < 0001) in group 1 and improved from 0.30 (IQR, 0.30-0.48) to 0.00 (0.00-0.00) in group 2 (P < 0.001). In group 1, the mean (standard deviation [SD]) AGM used preoperatively was 0.6 (0.9) which was significantly reduced to 0.2 (0.5) at 12 months postoperatively, whereas in group 2, at 12 months, the mean (SD) AGM used was reduced from 1.4 (0.6) to 1.1 (0.9). In group 1, 90.3% of eyes achieved complete success at the end of 1 year. The most common complication was hyphema, noted in 4 patients with 1 eye requiring an anterior chamber washout. CONCLUSION Ab interno microhook trabeculotomy (microLOT) combined with phacoemulsification in patients with open-angle glaucoma is an efficacious procedure with relatively minimal complications. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Devendra Maheshwari
- Department of Glaucoma, Aravind Eye Hospital & PG Institute of Ophthalmology, Tirunelveli, India.
| | | | - Rengappa Ramakrishnan
- Department of Glaucoma, Aravind Eye Hospital & PG Institute of Ophthalmology, Tirunelveli, India
| | - Madhavi Ramanatha Pillai
- Department of Glaucoma, Aravind Eye Hospital & PG Institute of Ophthalmology, Tirunelveli, India
| | - Drishti Chautani
- Department of Glaucoma, Aravind Eye Hospital & PG Institute of Ophthalmology, Tirunelveli, India
| | - Mohideen Abdul Kader
- Department of Glaucoma, Aravind Eye Hospital & PG Institute of Ophthalmology, Tirunelveli, India
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Harvey DH, Sugali CK, Mao W. Glucocorticoid-Induced Ocular Hypertension and Glaucoma. Clin Ophthalmol 2024; 18:481-505. [PMID: 38379915 PMCID: PMC10878139 DOI: 10.2147/opth.s442749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 01/22/2024] [Indexed: 02/22/2024] Open
Abstract
Glucocorticoid (GC) therapy is indicated in many diseases, including ocular diseases. An important side-effect of GC therapy is GC-induced ocular hypertension (GIOHT), which may cause irreversible blindness known as GC-induced glaucoma (GIG). Here, we reviewed the pathological changes that contribute to GIOHT including in the trabecular meshwork and Schlemm's canal at cellular and molecular levels. We also discussed the clinical aspects of GIOHT/GIG including disease prevalence, risk factors, the type of GCs, the route of GC administration, and management strategies.
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Affiliation(s)
- Devon Hori Harvey
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN, USA
- Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Chenna Kesavulu Sugali
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN, USA
- Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Weiming Mao
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN, USA
- Eugene and Marilyn Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN, USA
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6
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Zhang Y, Yu P, Zhang Y, Sugihara K, Zhu X, Zhang Y, Yang X, Li X, Liu Y, Zhang H, Yan X, Zhang H, Lin F, Song Y, Gao X, Yuan H, Tang G, Zhou W, Fan S, Dang G, Tang L, Chen W, Wang N, Park KH, Barton K, Aung T, Lam DSC, Weinreb RN, Xie L, Tanito M, Zeng L, Zhang X. Influence of Goniotomy Size on Treatment Safety and Efficacy for Primary Open-Angle Glaucoma: A Multicenter Study. Am J Ophthalmol 2023; 256:118-125. [PMID: 37573988 DOI: 10.1016/j.ajo.2023.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 08/01/2023] [Accepted: 08/02/2023] [Indexed: 08/15/2023]
Abstract
PURPOSE To compare the efficacy and safety of 120-, 240-, and 360-degree goniotomy (GT) with or without phacoemulsification with intraocular lens implantation (PEI) for patients with primary open-angle glaucoma (POAG). DESIGN Multicenter, retrospective, comparative, nonrandomized interventional study. METHODS Patients diagnosed with POAG who underwent GT with or without PEI were included, and divided into 6 groups: 1) standalone 120-degree GT (120GT); 2) standalone 240-degree GT (240GT); 3) standalone 360-degree GT (360GT); 4) PEI + 120GT; 5) PEI + 240GT; and 6) PEI + 360GT. Data on intraocular pressure (IOP), the number of ocular hypotensive medications, and complications were collected and compared. Success was defined as a postoperative IOP within the range of 6 to 18 mm Hg and a 20% reduction from baseline without further glaucoma surgery. Complete success and qualified success were defined as the above without and with ocular hypotensive medications, respectively. RESULTS Three hundred eight eyes of 231 patients were included with a mean follow-up of 14.4 ± 8.6 months (6.0-48.0 months). There were no significant differences in the reductions in IOP and number of medications and cumulative survival probability for complete and qualified success rates among the 3 groups of standalone GT and PEI + GT. The 360GT group had the highest proportion of hyphema with or without PEI. CONCLUSIONS 120GT, 240GT, and 360GT with or without PEI showed similar efficacy in reducing IOP and medications used in POAG. 360GT with or without PEI was more likely to cause hyphema compared with 120GT or 240GT. 120GT with or without PEI was sufficient for treating POAG with or without cataract..
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Affiliation(s)
- Yu Zhang
- From the State Key Laboratory of Ophthalmology (Yu Zhang, Yingzhe Zhang, F.L., Y.S., X.G., W.C., Xiulan Zhang), Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, Guangdong, China
| | - Ping Yu
- Department of Ophthalmology (P.Y., L.Z.), Chengdu First People's Hospital, Chengdu, Sichuan, China
| | - Yingzhe Zhang
- From the State Key Laboratory of Ophthalmology (Yu Zhang, Yingzhe Zhang, F.L., Y.S., X.G., W.C., Xiulan Zhang), Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, Guangdong, China
| | - Kazunobu Sugihara
- Department of Ophthalmology (K.S., M.T.), Shimane University Faculty of Medicine, Izumo, Japan
| | - Xiaomin Zhu
- Department of Ophthalmology (X.Z., L.X.), The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yao Zhang
- Department of Ophthalmology (Yao Zhang, L.T.), West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Xiao Yang
- Jinan Mingshui Eye Hospital (X.Y., X.L., S.F.), Jinan, Shandong, China
| | - Xiaoyan Li
- Department of Ophthalmology (X.L.), Handan City Eye Hospital (The Third Hospital of Handan), Handan, Hebei, China
| | - Yacong Liu
- Cangzhou Aier Eye Hospital (Y.L., W.Z.), Aier Eye Hospital Group, Cangzhou, Hebei, China
| | - Hengli Zhang
- Department of Ophthalmology (Hengli Zhang, X.Y., G.T.), Shijiazhuang People's Hospital, Shijiazhuang, Hebei, China
| | - Xiaowei Yan
- Department of Ophthalmology (Hengli Zhang, X.Y., G.T.), Shijiazhuang People's Hospital, Shijiazhuang, Hebei, China
| | - Hengkai Zhang
- Department of Ophthalmology (Hengkai Zhang, H.Y.), The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Fengbin Lin
- From the State Key Laboratory of Ophthalmology (Yu Zhang, Yingzhe Zhang, F.L., Y.S., X.G., W.C., Xiulan Zhang), Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, Guangdong, China
| | - Yunhe Song
- From the State Key Laboratory of Ophthalmology (Yu Zhang, Yingzhe Zhang, F.L., Y.S., X.G., W.C., Xiulan Zhang), Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, Guangdong, China
| | - Xinbo Gao
- From the State Key Laboratory of Ophthalmology (Yu Zhang, Yingzhe Zhang, F.L., Y.S., X.G., W.C., Xiulan Zhang), Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, Guangdong, China
| | - Huiping Yuan
- Department of Ophthalmology (Hengkai Zhang, H.Y.), The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Guangxian Tang
- Department of Ophthalmology (Hengli Zhang, X.Y., G.T.), Shijiazhuang People's Hospital, Shijiazhuang, Hebei, China
| | - Wenzong Zhou
- Cangzhou Aier Eye Hospital (Y.L., W.Z.), Aier Eye Hospital Group, Cangzhou, Hebei, China
| | - Sujie Fan
- Department of Ophthalmology (X.L.), Handan City Eye Hospital (The Third Hospital of Handan), Handan, Hebei, China
| | - Guangfu Dang
- Department of Ophthalmology (G.D.), The First Affiliated Hospital of Shandong First Medical University and Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China
| | - Li Tang
- Department of Ophthalmology (Yao Zhang, L.T.), West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Weirong Chen
- From the State Key Laboratory of Ophthalmology (Yu Zhang, Yingzhe Zhang, F.L., Y.S., X.G., W.C., Xiulan Zhang), Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, Guangdong, China
| | - Ningli Wang
- Beijing Tongren Eye Center (N.W.), Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Ki Ho Park
- Department of Ophthalmology (K.H.P.), Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Keith Barton
- NIHR Biomedical Research Centre (K.B.), Moorfields Eye Hospital NHS Foundation Trust, UCL Institute of Ophthalmology, London, United Kingdom
| | - Tin Aung
- Singapore Eye Research Institute (T.A.), Singapore National Eye Center, Singapore, Republic of Singapore
| | - Dennis S C Lam
- International Eye Research Institute of The Chinese University of Hong Kong (Shenzhen) (D.S.C.L.), Shenzhen, China
| | - Robert N Weinreb
- Hamilton Glaucoma Center (R.N.W.), Viterbi Family Department of Ophthalmology, and Shiley Eye Institute, University of California San Diego, La Jolla, California, USA
| | - Lin Xie
- Department of Ophthalmology (X.Z., L.X.), The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Masaki Tanito
- Department of Ophthalmology (K.S., M.T.), Shimane University Faculty of Medicine, Izumo, Japan
| | - Liuzhi Zeng
- Department of Ophthalmology (P.Y., L.Z.), Chengdu First People's Hospital, Chengdu, Sichuan, China.
| | - Xiulan Zhang
- From the State Key Laboratory of Ophthalmology (Yu Zhang, Yingzhe Zhang, F.L., Y.S., X.G., W.C., Xiulan Zhang), Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, Guangdong, China.
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7
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Chan PPM, Larson MD, Dickerson JE, Mercieca K, Koh VTC, Lim R, Leung EHY, Samuelson TW, Larsen CL, Harvey A, Töteberg-Harms M, Meier-Gibbons F, Shu-Wen Chan N, Sy JB, Mansouri K, Zhang X, Lam DSC. Minimally Invasive Glaucoma Surgery: Latest Developments and Future Challenges. Asia Pac J Ophthalmol (Phila) 2023; 12:537-564. [PMID: 38079242 DOI: 10.1097/apo.0000000000000646] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 10/12/2023] [Indexed: 12/21/2023] Open
Abstract
The development of minimally invasive glaucoma surgeries (MIGSs) was intended to provide safe and modestly efficacious modalities for early intervention of mild-to-moderate glaucoma, with minimal trauma and rapid recovery. They were mainly ab interno procedures that reduce intraocular pressure by facilitating the aqueous outflow by bypassing the trabecular meshwork resistance, reinforcing the uveoscleral flow via the supraciliary space, and reducing aqueous production by the ciliary body. While the cumulating evidence helps shape the role of the available MIGS, the exponential new development and advancement in this field has expanded the territory of MIGS. Apart from developing subconjunctival MIGS filtration devices (Xen gel stent and PRESERFLO MicroShunt), there is a tendency to revisit the "traditional" MIGS for alternative use and to modify the procedures with consideration of the fundamental aqueous outflow physiology. Combined MIGS has also been suggested, based on the theory that their different mechanisms may provide additive or synergistic effects. The advancement of laser procedures is also promising and could supplement unmet needs along the glaucoma treatment algorithm. This review examines the broad array of MIGS, updates the recent findings, discusses their potential alternative applications, and explores future challenges.
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Affiliation(s)
- Poemen P M Chan
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
- Department of Ophthalmology and Visual Sciences, Lam Kin Chung. Jet King-Shing Ho Glaucoma Treatment and Research Centre, The Chinese University of Hong Kong, Hong Kong, China
| | | | - Jaime E Dickerson
- Sight Sciences, Menlo Park, CA, USA
- University of North Texas Health Science Center, North Texas Eye Research Institute, Fort Worth, TX, USA
| | | | - Victor Teck Chang Koh
- Department of Ophthalmology, National University Health System, Singapore
- Centre for Innovation and Precision Eye Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ridia Lim
- Department of Ophthalmology, Sydney Eye Hospital, Sydney, Australia
- Save Sight Institute, Sydney Medical School, The University of Sydney, Sydney, Australia
| | - Enne Hiu Ying Leung
- The C-MER Dennis Lam & Partners Eye Center, C-MER International Eye Care Group, Hong Kong, China
| | - Thomas W Samuelson
- Minnesota Eye Consultants, Bloomington, MN, US
- Department of Ophthalmology, University of Minnesota, MN, US
| | - Christine L Larsen
- Minnesota Eye Consultants, Bloomington, MN, US
- Department of Ophthalmology, University of Minnesota, MN, US
| | | | - Marc Töteberg-Harms
- Department of Ophthalmology, Augusta University, Medical College of Georgia, Augusta, GA, USA
| | | | | | - Jessica Belle Sy
- Department of Ophthalmology, Sydney Eye Hospital, Sydney, Australia
- Baguio General Hospital and Medical Center, Baguil City, Benguet, Philippines
| | - Kaweh Mansouri
- Glaucoma Center, Swiss Visio, Clinique de Montchoisi, Lausanne, Switzerland
| | - Xiulan Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Dennis S C Lam
- The C-MER Dennis Lam & Partners Eye Center, C-MER International Eye Care Group, Hong Kong, China
- The International Eye Research Institute of The Chinese University of Hong Kong (Shenzhen), Shenzhen, China
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8
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Strohmaier CA, Wanderer D, Zhang X, Agarwal D, Toomey CB, Wahlin K, Zhang HF, Stamer WD, Weinreb RN, McDonnell FS, Huang AS. Greater Outflow Facility Increase After Targeted Trabecular Bypass in Angiographically Determined Low-low Regions. Ophthalmol Glaucoma 2023; 6:570-579. [PMID: 37348815 PMCID: PMC10917462 DOI: 10.1016/j.ogla.2023.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/31/2023] [Accepted: 06/14/2023] [Indexed: 06/24/2023]
Abstract
PURPOSE To investigate the impact of trabecular bypass surgery targeted to angiographically determined high- vs. low-aqueous humor outflow areas on outflow facility (C) and intraocular pressure (IOP). DESIGN Ex vivo comparative study. SUBJECTS Postmortem ex vivo porcine and human eyes. METHODS Porcine (n = 14) and human (n = 13) whole globes were acquired. In both species, anterior segments were dissected, mounted onto a perfusion chamber, and perfused using Dulbecco's phosphate buffered solution containing glucose in a constant flow paradigm to achieve a stable baseline. Fluorescein was perfused into the anterior chamber and used to identify baseline segmental high- and low-flow regions of the conventional outflow pathways. The anterior segments were divided into 2 groups, and a 5 mm needle goniotomy was performed in either a high- or low-flow area. Subsequently, C and IOP were quantitatively reassessed and compared between surgery in baseline "high-flow" and "low-flow" region eyes followed by indocyanine green angiography. MAIN OUTCOME MEASURES Outflow facility. RESULTS In all eyes, high- and low-flow segments could be identified. Performing a 5-mm goniotomy increased outflow facility to a variable extent depending on baseline flow status. In the porcine high-flow group, C increased from 0.31 ± 0.09 to 0.39 ± 0.09 μL/mmHg/min (P = 0.12). In the porcine low-flow group, C increased from 0.29 ± 0.03 to 0.56 ± 0.10 μL/mmHg/min (P < 0.001). In the human high-flow group, C increased from 0.38 ± 0.20 to 0.41 ± 0.20 μL/mmHg/min (P = 0.02). In the human low-flow group, C increased from 0.25 ± 0.11 to 0.32 ± 0.11 μL/mmHg/min (<0.001). There was statistically significant greater increase in C for eyes where surgery was targeted to baseline low-flow regions in both porcine (0.07 ± 0.09 vs. 0.27 ± 0.13, P = 0.007 μL/mmHg/min, high vs low flow) and human eyes (0.03 ± 0.03 vs. 0.07 ± 0.02, P = 0.03 μL/mmHg/min, high vs. low flow). CONCLUSIONS Targeting surgery to low-flow areas of the trabecular meshwork yields higher overall facility increase and IOP reduction compared to surgery in high-flow areas. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Clemens A Strohmaier
- Department of Ophthalmology and Optometry, Kepler University Hospital, Johannes Kepler University, Linz, Austria; The Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, University of California, San Diego, California.
| | - Daniel Wanderer
- The Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, University of California, San Diego, California
| | - Xiaowei Zhang
- The Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, University of California, San Diego, California
| | - Devansh Agarwal
- The Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, University of California, San Diego, California
| | - Christopher B Toomey
- The Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, University of California, San Diego, California
| | - Karl Wahlin
- The Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, University of California, San Diego, California
| | - Hao F Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois
| | - W Daniel Stamer
- Department of Biomedical Engineering, Duke University, Durham, North Carolina
| | - Robert N Weinreb
- The Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, University of California, San Diego, California
| | | | - Alex S Huang
- The Viterbi Family Department of Ophthalmology, Hamilton Glaucoma Center, Shiley Eye Institute, University of California, San Diego, California
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9
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Johnstone M, Xin C, Martin E, Wang R. Trabecular Meshwork Movement Controls Distal Valves and Chambers: New Glaucoma Medical and Surgical Targets. J Clin Med 2023; 12:6599. [PMID: 37892736 PMCID: PMC10607137 DOI: 10.3390/jcm12206599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/09/2023] [Accepted: 08/30/2023] [Indexed: 10/29/2023] Open
Abstract
Herein, we provide evidence that human regulation of aqueous outflow is by a pump-conduit system similar to that of the lymphatics. Direct observation documents pulsatile aqueous flow into Schlemm's canal and from the canal into collector channels, intrascleral channels, aqueous veins, and episcleral veins. Pulsatile flow in vessels requires a driving force, a chamber with mobile walls and valves. We demonstrate that the trabecular meshwork acts as a deformable, mobile wall of a chamber: Schlemm's canal. A tight linkage between the driving force of intraocular pressure and meshwork deformation causes tissue responses in milliseconds. The link provides a sensory-motor baroreceptor-like function, providing maintenance of a homeostatic setpoint. The ocular pulse causes meshwork motion oscillations around the setpoint. We document valves entering and exiting the canal using real-time direct observation with a microscope and multiple additional modalities. Our laboratory-based high-resolution SD-OCT platform quantifies valve lumen opening and closing within milliseconds synchronously with meshwork motion; meshwork tissue stiffens, and movement slows in glaucoma tissue. Our novel PhS-OCT system measures nanometer-level motion synchronous with the ocular pulse in human subjects. Movement decreases in glaucoma patients. Our model is robust because it anchors laboratory studies to direct observation of physical reality in humans with glaucoma.
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Affiliation(s)
- Murray Johnstone
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA;
| | - Chen Xin
- Beijing Tongren Eye Center, Beijing Institute of Ophthalmology, Beijing 100730, China
- Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
| | - Elizabeth Martin
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
| | - Ruikang Wang
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA;
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
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10
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Kicińska AK, Rękas M. Safety and Efficacy of Three Modifications of Canaloplasty to Treat Open-Angle Glaucoma: 3-Year Outcomes. J Clin Med 2023; 12:6475. [PMID: 37892612 PMCID: PMC10607351 DOI: 10.3390/jcm12206475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
BACKGROUND This is a report of 3-year results of a prospective assessment of three modifications of canaloplasty (C): ab externo (ABeC), mini-canaloplasty (miniABeC), and ab interno (ABiC) performed concomitantly with cataract removal in subjects suffering from primary open-angle glaucoma (POAG). METHODS Forty-eight individuals were randomized for one of the surgeries: ABeC, miniABeC, or ABiC and cataract removal-16 eyes for each group. Follow-up examinations were carried out on the day of the surgery, on days 1 and 7, after 1, 3, 6 months, and at 1, 2, and 3 years. Complete and qualified success was an IOP ≤ 15 mmHg without or with antiglaucoma eye drops, respectively. The IOP reduction of 20% or more was considered an additional success criterion. RESULTS Within three years the probability of qualified success was ABiC and miniABeC-94%, ABeC-100%, and of complete success ABiC-75%, miniABeC-100%. At the 3-year follow-up, the median IOP decreased from 22 to 15 mmHg in the ABeC group (p = 0.001), from 22 to 15 mmHg in the miniABeC group 15 (p < 0.001), and from 21 to 15 mmHg in the ABiC group (p = 0.001) compared to the post-washout stage. The IOP dropped by 20% or more without medications in 56.2% of patients post ABiC, 68.8% post miniABeC and 75% post ABeC. The median number of antiglaucoma medications dropped in all three groups; at the 3-year follow-up, only one patient following ABeC and four subjects following miniABeC required treatment. One patient required reoperation and further intensification of topical treatment-post miniABeC. The levels of IOP, CDVA, and success probability at the 36-month follow-up showed no significant difference for individual groups. CONCLUSIONS ABeC, miniABeC, and ABiC have significant IOP-lowering potential in individuals diagnosed with POAG at a mild to moderate stage and no history of IOP ≥ 30 mmHg with a good safety profile.
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Affiliation(s)
- Aleksandra K. Kicińska
- Ophthalmology Department, Military Institute of Medicine—National Research Institute, 04-141 Warsaw, Poland;
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11
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Asaoka R, Nakakura S, Mochizuki T, Ishida A, Fujino Y, Ishii K, Obana A, Tanito M, Kiuchi Y. Which is More Effective and Safer? Comparison of Propensity Score-Matched Microhook Ab Interno Trabeculotomy and iStent Inject. Ophthalmol Ther 2023; 12:2757-2768. [PMID: 37548906 PMCID: PMC10441850 DOI: 10.1007/s40123-023-00777-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 07/17/2023] [Indexed: 08/08/2023] Open
Abstract
INTRODUCTION The purpose of this study was to compare the surgical outcomes between ab interno trabeculotomy (LOT) and iStent inject W implantation (iStent) both combined with cataract surgery, matching the background factors including age, intraocular pressure (IOP), medication score, central corneal thickness (CCT), and axial length. METHODS A total of 100 eyes from 75/79 patients with primary open-angle glaucoma were included in the LOT/iStent groups. The background factors were matched between the two groups using the propensity score. RESULTS There were no significant differences in age, IOP, medication score, CCT, and axial length, preoperatively. The postoperative medication scores were 1.3 ± 1.2 and 1.2 ± 1.2 in the LOT and iStent groups. The postoperative IOPs were 12.8 ± 2.8 and 13.1 ± 2.4 mmHg in the LOT and iStent groups, respectively. The changes in the medication score were - 0.64 ± 1.4 and - 0.44 ± 1.6 in the LOT and iStent groups, respectively. The changes in the IOP were - 2.1 ± 3.3 and - 1.5 ± 3.0 mmHg in the LOT and iStent groups, respectively. These values were not significantly different between the two groups. The postoperative IOP and changes in the IOP were significantly associated with preoperative IOP and CCT. There was no significant difference in the occurrence of postoperative complications (hyphema, 11.0% and 6.0%, and transient ocular hypertension, 8.0% and 5.0%, in the LOT and iStent groups, respectively). CONCLUSION LOT and iStent have similar surgical outcomes with sufficient safety. Postoperative IOP was significantly associated with preoperative IOP and CCT in both groups.
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Grants
- 19H01114 Ministry of Education, Science, Techonology, Sports and Cultrue of Japan
- 18KK0253 Ministry of Education, Science, Techonology, Sports and Cultrue of Japan
- 20K09784 Ministry of Education, Science, Techonology, Sports and Cultrue of Japan
- 20K18337 Ministry of Education, Science, Techonology, Sports and Cultrue of Japan
- Japan Glaucoma Society
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Affiliation(s)
- Ryo Asaoka
- Department of Ophthalmology, Seirei Hamamatsu General Hospital, 2-12-12 Sumiyoshi, Naka-Ku, Hamamatsu City, Shizuoka, Japan.
- Seirei Christopher University, Shizuoka, Japan.
| | - Shunsuke Nakakura
- Department of Ophthalmology, Saneikai Tsukazaki Hospital, Hyogo, Japan
| | - Tsukasa Mochizuki
- Department of Ophthalmology and Visual Science, Hiroshima University, Hiroshima, Japan
| | - Akiko Ishida
- Department of Ophthalmology, Faculty of Medicine, Shimane University, Shimane, Japan
| | - Yuri Fujino
- Department of Ophthalmology, Seirei Hamamatsu General Hospital, 2-12-12 Sumiyoshi, Naka-Ku, Hamamatsu City, Shizuoka, Japan
- Department of Ophthalmology, Faculty of Medicine, Shimane University, Shimane, Japan
| | - Kaori Ishii
- Department of Ophthalmology, Seirei Hamamatsu General Hospital, 2-12-12 Sumiyoshi, Naka-Ku, Hamamatsu City, Shizuoka, Japan
| | - Akira Obana
- Department of Ophthalmology, Seirei Hamamatsu General Hospital, 2-12-12 Sumiyoshi, Naka-Ku, Hamamatsu City, Shizuoka, Japan
| | - Masaki Tanito
- Department of Ophthalmology, Faculty of Medicine, Shimane University, Shimane, Japan
| | - Yoshiaki Kiuchi
- Department of Ophthalmology and Visual Science, Hiroshima University, Hiroshima, Japan
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12
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Bhartiya S, Aktas Z, Ichhpujani P. Is GATT the Answer? J Curr Glaucoma Pract 2023; 17:167-168. [PMID: 38269261 PMCID: PMC10803277 DOI: 10.5005/jp-journals-10078-1425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024] Open
Abstract
How to cite this article: Bhartiya S, Aktas Z, Ichhpujani P. Is GATT the Answer? J Curr Glaucoma Pract 2023;17(4):167-168.
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Affiliation(s)
- Shibal Bhartiya
- Department of Glaucoma Services, Fortis Memorial Hospital, Gurugram, Haryana, India
| | - Zeynep Aktas
- Department of Ophthalmology, School of Medicine, Atilim University, Ankara, Turkey
| | - Parul Ichhpujani
- Department of Ophthalmology, Glaucoma Service, Government Medical College, Chandigarh, India
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13
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Wagner IV, Ang B, Checo L, Simsek D, Draper C, Dorairaj S. Spotlight on Schlemm's Canal MicroStent Injection in Patients with Glaucoma. Clin Ophthalmol 2023; 17:1557-1564. [PMID: 37288002 PMCID: PMC10243342 DOI: 10.2147/opth.s388293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/30/2023] [Indexed: 06/09/2023] Open
Abstract
Minimally invasive glaucoma surgery (MIGS) has revolutionized glaucoma care with its favorable safety profile and ability to delay or minimize the need for traditional, bleb-based procedures. Microstent device implantation is a type of angle-based MIGS, which reduces intraocular pressure (IOP) through bypass of the juxtacanalicular trabecular meshwork (TM) and facilitation of aqueous outflow into the Schlemm's canal. Although there are limited microstent devices on the market, multiple studies have evaluated the safety and efficacy of iStent® (Glaukos Corp.), iStent Inject® (Glaukos Corp.), and Hydrus® Microstent (Alcon) in the treatment of mild-to-moderate open-angle glaucoma, with and without concurrent phacoemulsification. This review attempts to provide a comprehensive evaluation of injectable angle-based microstent MIGS devices in the treatment of glaucoma.
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Affiliation(s)
| | - Bryan Ang
- Department of Ophthalmology, Tan Tock Seng Hospital, Singapore
| | - Leticia Checo
- Department of Ophthalmology, Mayo Clinic, Jacksonville, FL, USA
| | - Derya Simsek
- Department of Ophthalmology, Baskent University Medical School, Ankara, Turkey
| | | | - Syril Dorairaj
- Department of Ophthalmology, Mayo Clinic, Jacksonville, FL, USA
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Karimi A, Crouch DJ, Razaghi R, Crawford Downs J, Acott TS, Kelley MJ, Behnsen JG, Bosworth LA, Sheridan CM. Morphological and biomechanical analyses of the human healthy and glaucomatous aqueous outflow pathway: Imaging-to-modeling. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2023; 236:107485. [PMID: 37149973 DOI: 10.1016/j.cmpb.2023.107485] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/09/2023] [Accepted: 03/13/2023] [Indexed: 05/09/2023]
Abstract
BACKGROUND AND OBJECTIVE Intraocular pressure (IOP) is maintained via a dynamic balance between the production of aqueous humor and its drainage through the trabecular meshwork (TM), juxtacanalicular connective tissue (JCT), and Schlemm's canal (SC) endothelium of the conventional outflow pathway. Primary open angle glaucoma (POAG) is often associated with IOP elevation that occurs due to an abnormally high outflow resistance across the outflow pathway. Outflow tissues are viscoelastic and actively interact with aqueous humor dynamics through a two-way fluid-structure interaction coupling. While glaucoma affects the morphology and stiffness of the outflow tissues, their biomechanics and hydrodynamics in glaucoma eyes remain largely unknown. This research aims to develop an image-to-model method allowing the biomechanics and hydrodynamics of the conventional aqueous outflow pathway to be studied. METHODS We used a combination of X-ray computed tomography and scanning electron microscopy to reconstruct high-fidelity, eye-specific, 3D microstructural finite element models of the healthy and glaucoma outflow tissues in cellularized and decellularized conditions. The viscoelastic TM/JCT/SC complex finite element models with embedded viscoelastic beam elements were subjected to a physiological IOP load boundary; the stresses/strains and the flow state were calculated using fluid-structure interaction and computational fluid dynamics. RESULTS Based on the resultant hydrodynamics parameters across the outflow pathway, the primary site of outflow resistance in healthy eyes was in the JCT and immediate vicinity of the SC inner wall, while the majority of the outflow resistance in the glaucoma eyes occurred in the TM. The TM and JCT in the glaucoma eyes showed 1.32-fold and 1.13-fold larger beam thickness and smaller trabecular space size (2.24-fold and 1.50-fold) compared to the healthy eyes. CONCLUSIONS Characterizing the accurate morphology of the outflow tissues may significantly contribute to constructing more accurate, robust, and reliable models, that can eventually help to better understand the dynamic IOP regulation, hydrodynamics of the aqueous humor, and outflow resistance dynamic in the human eyes. This model demonstrates proof of concept for determining changes to outflow resistance in healthy and glaucomatous tissues and thus may be utilized in larger cohorts of donor tissues where disease specificity, race, age, and gender of the eye donors may be accounted for.
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Affiliation(s)
- Alireza Karimi
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Devon J Crouch
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L7 8TX, United Kingdom
| | - Reza Razaghi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, United States
| | - J Crawford Downs
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Ted S Acott
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States; Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, Oregon, United States
| | - Mary J Kelley
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States; Department of Integrative Biosciences, Oregon Health & Science University, Portland, Oregon, United States
| | - Julia G Behnsen
- Department of Mechanical, Materials, and Aerospace Engineering, University of Liverpool, Liverpool, L69 6GB, United Kingdom
| | - Lucy A Bosworth
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L7 8TX, United Kingdom
| | - Carl M Sheridan
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L7 8TX, United Kingdom.
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15
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Kelly RA, McDonnell FS, De Ieso ML, Overby DR, Stamer WD. Pressure Clamping During Ocular Perfusions Drives Nitric Oxide-Mediated Washout. Invest Ophthalmol Vis Sci 2023; 64:36. [PMID: 37358489 PMCID: PMC10297780 DOI: 10.1167/iovs.64.7.36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 05/30/2023] [Indexed: 06/27/2023] Open
Abstract
Purpose The aim of this study was to test the hypothesis that nitric oxide (NO) mediates a pressure-dependent, negative feedback loop that maintains conventional outflow homeostasis and thus IOP. If true, holding pressure during ocular perfusions will result in uncontrolled production of NO, hyper-relaxation of the trabecular meshwork, and washout. Methods Paired porcine eyes were perfused at constant pressure of 15 mm Hg. After 1 hour acclimatization, one eye was exchanged with N5-[imino(nitroamino)methyl]-L-ornithine, methyl ester, monohydrochloride (L-NAME) (50 µm) and the contralateral eye with DBG, and perfused for 3 hours. In a separate group, one eye was exchanged with DETA-NO (100 nM) and the other with DBG and perfused for 30 minutes. Changes in conventional outflow tissue function and morphology were monitored. Results Control eyes exhibited a washout rate of 15% (P = 0.0026), whereas eyes perfused with L-NAME showed a 10% decrease in outflow facility from baseline over 3 hours (P < 0.01); with nitrite levels in effluent positively correlating with time and facility. Compared with L-NAME-treated eyes, significant morphological changes in control eyes included increased distal vessel size, number of giant vacuoles, and juxtacanalicular tissue separation from the angular aqueous plexi (P < 0.05). For 30-minute perfusions, control eyes showed a washout rate of 11% (P = 0.075), whereas DETA-NO-treated eyes showed an increased washout rate of 33% from baseline (P < 0.005). Compared with control eyes, significant morphological changes in DETA-NO-treated eyes also included increased distal vessel size, number of giant vacuoles and juxtacanalicular tissue separation (P < 0.05). Conclusions Uncontrolled NO production is responsible for washout during perfusions of nonhuman eyes where pressure is clamped.
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Affiliation(s)
- Ruth A. Kelly
- Ophthalmology Department, Duke University, Durham, North Carolina, United States
| | - Fiona S. McDonnell
- Ophthalmology Department, Duke University, Durham, North Carolina, United States
- Ophthalmology Department, University of Utah, Utah, United States
| | - Michael L. De Ieso
- Ophthalmology Department, Duke University, Durham, North Carolina, United States
| | - Darryl R. Overby
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - W. Daniel Stamer
- Ophthalmology Department, Duke University, Durham, North Carolina, United States
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Suzuki K, Shinmei Y, Hirooka K, Kanaya R, Shinkai A, Kijima R, Chin S, Ito YM, Ishida S. Reduction of Intraocular Pressure and Aqueous Outflow Resistance After Modified 360-degree Suture Trabeculotomy. J Glaucoma 2023; 32:204-209. [PMID: 36223302 DOI: 10.1097/ijg.0000000000002135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 09/27/2022] [Indexed: 11/26/2022]
Abstract
PRCIS Decreasing aqueous outflow resistance at trabecular meshwork is the main mechanism of modified 360-degree suture trabeculotomy (ST), and the preoperative C-value, which shows aqueous outflow resistance, is likely to be useful for predicting intraocular pressure (IOP) reduction. PURPOSE To clarify the mechanism of IOP reduction and the preoperative prognostic predictor of modified 360-degree ST. MATERIALS AND METHODS Forty-three eyes of 32 patients with glaucoma who underwent ST at Hokkaido University Hospital between April 2017 and February 2020 were enrolled. The records of postoperative IOP and coefficient of aqueous outflow (C-value) after ST were reviewed from clinical charts retrospectively. Preoperative IOP and C-values were also reviewed and considered as the baseline. RESULTS Although the differences were not significant, IOP decreased to 15.4±3.3 mm Hg at 3 months ( P =0.10) and 16.1±3.8 mm Hg at 6 months ( P =0.21). In addition, there were significant decreases in anti-glaucoma medication scores at both 3 and 6 months after surgery ( P <0.01). The C-value increased significantly to 0.24±0.11 µL/min/mm Hg at 3 months ( P <0.01) and increased significantly to 0.27±0.14 µL/min/mm Hg at 6 months ( P <0.01). The rates of change in IOP were negatively correlated with that in the C-value at 3 months ( r =-0.49 P <0.01) and 6 months ( r =-0.46 P <0.01). The success rate (IOP<21 mm Hg, IOP reduction>20%) was greater in the low baseline C-value group (≤0.17) than high baseline C-value group (>0.17) ( P <0.05), and the baseline IOP and C-values were statistically significant in association with the success ( P <0.05) at 6 months. CONCLUSIONS Increased conventional outflow by the elimination of the aqueous outflow resistance at the trabecular meshwork is the main mechanism of IOP reduction after ST. Preoperative examination of tonographic outflow facility may be useful for predicting the IOP reduction and outcome of ST.
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Affiliation(s)
- Kayo Suzuki
- Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo
| | - Yasuhiro Shinmei
- Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo
| | - Kiriko Hirooka
- Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo
| | - Rina Kanaya
- Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo
| | - Akihiro Shinkai
- Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo
| | - Riki Kijima
- Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo
| | - Shinki Chin
- Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo
| | - Yoichi M Ito
- Data Science Center, Promotion Unit, Institute of Health Science Innovation for Medical Care, Hokkaido University Hospital, Hokkaido, Japan
| | - Susumu Ishida
- Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo
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Rao A, Khan S, Mukherjee S. 'Microincisional trabeculectomy for glaucoma". PLoS One 2023; 18:e0286020. [PMID: 37205654 DOI: 10.1371/journal.pone.0286020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 05/06/2023] [Indexed: 05/21/2023] Open
Abstract
PURPOSE To evaluate the short-term clinical outcomes of microincisional trabeculectomy (MIT), a new technique of ab-interno trabeculectomy. METHODS Consecutive patients with open-angle glaucoma identified from the hospital database that underwent MIT with or without cataract surgery between September 2021 to June 2022 at a tertiary eye centre in East India, were screened. Those with a follow-up of < 6 months or with incomplete data were excluded. MIT was done ab-interno using microscissors and microforceps in 2-4 clock hours of the nasal angle via a temporal incision. The intraocular pressure (IOP) reduction at 6 months, and reduction in the number of medications after surgery were analysed. Surgical success (IOP>6 and <22 mm Hg), complications, angle features on anterior segment optical coherence tomography (ASOCT), and the need for additional surgeries were analysed. RESULTS We included thirty-two eyes of 32 patients with open-angle glaucoma (including n = 9 eyes that underwent concurrent cataract surgery) with a preoperative mean IOP of 22 ±11.1 mm Hg and visual field index of 47±37.9%. All eyes achieved >30% IOP reduction, with a final IOP of 14±6.9 mm Hg at 6 months. Surgical success in 31 of 32 eyes with complete success seen in 28 eyes with none of the eyes requiring >1 medication for IOP control. Hyphema was seen in 4 eyes, while transient IOP spikes at 1 day-1 month were seen in 5 eyes, none of which required any additional interventions. One eye with persistent raised IOP at 1 month required incisional trabeculectomy for uncontrolled IOP with 2 medications. CONCLUSION MIT, a new technique of ab-interno trabeculectomy, is effective in terms of IOP control and reduction in the number of medications while having fewer complications. Long-term studies comparing the efficacy of MIT with incisional trabeculectomy, or other procedures are warranted in the future.
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Affiliation(s)
- Aparna Rao
- Glaucoma Service, LV Prasad Eye Institute, Patia, Bhubaneswar, India
| | - Sardar Khan
- Glaucoma Service, LV Prasad Eye Institute, Patia, Bhubaneswar, India
| | - Sujoy Mukherjee
- Glaucoma Service, LV Prasad Eye Institute, Patia, Bhubaneswar, India
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Asafali F, Rajamani M, Ramamurthy C, Chaya CJ, M V. Relationship of degrees of gonioscopy assisted transluminal trabeculotomy and trabecular shelf to success using a marker suture technique. Eye (Lond) 2023; 37:132-138. [PMID: 35031703 PMCID: PMC9829732 DOI: 10.1038/s41433-021-01838-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 10/05/2021] [Accepted: 11/01/2021] [Indexed: 01/17/2023] Open
Abstract
OBJECTIVE To evaluate the safety and efficacy of gonioscopy-assisted transluminal trabeculotomy (GATT) using a marker suture which could be a viable low cost alternative to an illuminated micro catheter, by helping the surgeon identify obstruction to suture passage, and estimate the degree of Schlemm's canal cannulated. SUBJECT/METHODS Thirty four eyes with 360° of open angles with uncontrolled IOP despite maximal medical therapy, non-compliant to medical therapy or failed incisional glaucoma surgery underwent GATT. 5-0 or 6-0 Prolene® suture was used to cannulate Schlemm's canal. An 8-0 Vicryl® suture was tied around the trailing portion of the Prolene® suture and acted as a guide to estimate the length of Schlemm's canal negotiated. The degree of trabecular shelf seen was noted postoperatively. RESULTS Mean baseline IOP was 24.7 ± 8.8 mm Hg (range 13-54 mmHg). Six patients had appositional angle closure and the rest had open angles. Patients were followed up for a period of 45.0 ± 14.6weeks (range 6 weeks-2 years). The mean IOP 6 weeks after surgery was 13 ± 3.3 mm Hg, and at 1 year was 13.5 ± 2.6 mm Hg. Mean degrees of cannulation achieved was 264.5 ± 84.0˚ (90-360˚). The mean number of medications prior to surgery was 2.1 ± 1.0 and at 6 months review was 0.15 ± 0.3. The absolute success was 92.6% 1 year after surgery. Nine patients lost some of their trabecular shelf in the postoperative period, but this did not seem to affect the short term success rate. DISCUSSION Suture GATT is a safe and effective procedure to lower IOP even in patients with partial cannulation. Adding a marker suture is a useful adjunct to help identify the length of Schlemm's canal successfully cannulated and monitor progress of the Prolene® suture.
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Affiliation(s)
- Fasna Asafali
- Department of Glaucoma, The Eye Foundation, 582A, D.B.Road, R.S. Puram, Coimbatore, 641002, Tamilnadu, India
| | - Muralidhar Rajamani
- Department of Glaucoma, The Eye Foundation, 582A, D.B.Road, R.S. Puram, Coimbatore, 641002, Tamilnadu, India.
| | - Chitra Ramamurthy
- Department of Glaucoma, The Eye Foundation, 582A, D.B.Road, R.S. Puram, Coimbatore, 641002, Tamilnadu, India
| | - Craig J Chaya
- Department of Ophthalmology & Visual Sciences, University of Utah, Salt Lake City, USA
| | - Vaishnavi M
- Department of Glaucoma, The Eye Foundation, 582A, D.B.Road, R.S. Puram, Coimbatore, 641002, Tamilnadu, India
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Karimi A, Halabian M, Razaghi R, Downs JC, Kelley MJ, Acott TS. Modeling the Endothelial Glycocalyx Layer in the Human Conventional Aqueous Outflow Pathway. Cells 2022; 11:3925. [PMID: 36497183 PMCID: PMC9740116 DOI: 10.3390/cells11233925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/30/2022] [Accepted: 12/03/2022] [Indexed: 12/07/2022] Open
Abstract
A layer of proteoglycans and glycoproteins known as glycocalyx covers the surface of the trabecular meshwork (TM), juxtacanalicular tissue (JCT), and Schlemm's canal (SC) inner wall of the conventional aqueous outflow pathway in the eye. This has been shown to play a role in the mechanotransduction of fluid shear stress and in the regulation of the outflow resistance. The outflow resistance in the conventional outflow pathway is the main determinant of the intraocular pressure (IOP) through an active, two-way, fluid-structure interaction coupling between the outflow tissues and aqueous humor. A 3D microstructural finite element (FE) model of a healthy human eye TM/JCT/SC complex with interspersed aqueous humor was constructed. A very thin charged double layer that represents the endothelial glycocalyx layer covered the surface of the elastic outflow tissues. The aqueous humor was modeled as electroosmotic flow that is charged when it is in contact with the outflow tissues. The electrical-fluid-structure interaction (EFSI) method was used to couple the charged double layer (glycocalyx), fluid (aqueous humor), and solid (outflow tissues). When the IOP was elevated to 15 mmHg, the maximum aqueous humor velocity in the EFSI model was decreased by 2.35 mm/s (9%) compared to the fluid-structure interaction (FSI) model. The charge or electricity in the living human conventional outflow pathway generated by the charged endothelial glycocalyx layer plays a minor biomechanical role in the resultant stresses and strains as well as the hydrodynamics of the aqueous humor.
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Affiliation(s)
- Alireza Karimi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Mahdi Halabian
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Reza Razaghi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - J. Crawford Downs
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Mary J. Kelley
- Departments of Ophthalmology and Integrative Biosciences, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Ted S. Acott
- Departments of Ophthalmology and Biochemistry and Molecular Biology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
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20
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Segmental outflow dynamics in the trabecular meshwork of living mice. Exp Eye Res 2022; 225:109285. [PMID: 36273576 DOI: 10.1016/j.exer.2022.109285] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/10/2022] [Accepted: 10/14/2022] [Indexed: 12/29/2022]
Abstract
Aqueous humour does not drain uniformly through the trabecular meshwork (TM), but rather follows non-uniform or "segmental" routes. In this study, we examined whether segmental outflow patterns in the TM change over time in living mice and whether such changes are affected by age. Segmental outflow patterns were labelled by constant-pressure infusion of fluorescent tracer microparticles into the anterior chamber of anesthetised C57BL/6J mice at 3 or 8 months of age. Two different tracer colours were infused at separate time points with an interval of Δt = 0, 2, 7 or 14 days. In a separate experiment, one tracer was infused in vivo while the second tracer was infused ex vivo after 2 days. The spatial relationship between the two tracer patterns was analysed using the Pearson's correlation coefficient, r. In 3-month-old mice, there was a time-dependent decay in r, which was near unity at Δt = 0 and near zero at Δt = 14 days. In 8-month-old mice, r remained elevated for 14 days. Segmental outflow patterns measured in young mice ex vivo were not significantly different from those measured in vivo after accounting for the expected changes over 2 days. Therefore, segmental outflow patterns are not static in the TM but redistribute over time, achieving near complete loss of correlation by 2 weeks in young healthy mice. There is an age-related decline in the rate at which segmental outflow patterns redistribute in the TM. Further research is needed to understand the dynamic factors controlling segmental outflow.
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21
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Wagner IV, Stewart MW, Dorairaj SK. Updates on the Diagnosis and Management of Glaucoma. Mayo Clin Proc Innov Qual Outcomes 2022; 6:618-635. [PMID: 36405987 PMCID: PMC9673042 DOI: 10.1016/j.mayocpiqo.2022.09.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Glaucoma is the leading cause of blindness throughout the world (after cataracts); therefore, general physicians should be familiar with the diagnosis and management of affected patients. Glaucomas are usually categorized by the anatomy of the anterior chamber angle (open vs narrow/closed), rapidity of onset (acute vs chronic), and major etiology (primary vs secondary). Most glaucomas are primary (ie, without a contributing comorbidity); however, several coexisting ophthalmic conditions may serve as the underlying etiologies of secondary glaucomas. Chronic glaucoma occurs most commonly; thus, regular eye examinations should be performed in at-risk patients to prevent the insidious loss of vision that can develop before diagnosis. Glaucoma damages the optic nerve and retinal nerve fiber layer, leading to peripheral and central visual field defects. Elevated intraocular pressure (IOP), a crucial determinant of disease progression, remains the only modifiable risk factor; thus, all current treatments (medications, lasers, and operations) aim to reduce the IOP. Pharmacotherapy is the usual first-line therapy, but noncompliance, undesirable adverse effects, and cost limit effectiveness. Laser and surgical treatments may lower IOP significantly over long periods and may be more cost effective than pharmacotherapy, but they are plagued by greater procedural risks and frequent treatment failures. Traditional incisional procedures have recently been replaced by several novel, minimally invasive glaucoma surgeries with improved safety profiles and only minimal decreases in efficacy. Minimally invasive glaucoma surgeries have dramatically transformed the surgical management of glaucoma; nevertheless, large, randomized trials are required to assess their long-term efficacy.
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Key Words
- ACA, anterior chamber angle
- ACG, angle-closure glaucoma
- AIT, ab-interno trabeculotomy
- CAI, carbonic anhydrase inhibitor
- CE, cataract extraction
- GDD, glaucoma drainage device
- IOP, intraocular pressure
- KDB, Kahook Dual Blade
- MIGS, minimally invasive glaucoma surgery
- MMC, mitomycin C
- OAG, open-angle glaucoma
- OCT, optical coherence tomography
- ONH, optic nerve head
- PGA, prostaglandin analog
- PGI, PAUL glaucoma implant
- POAG, primary open-angle glaucoma
- RNFL, retinal nerve fiber layer
- SLT, selective laser trabeculoplasty
- TM, trabecular meshwork
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Affiliation(s)
- Isabella V. Wagner
- Department of Ophthalmology, Mayo Clinic School of Medicine, Jacksonville, FL
| | - Michael W. Stewart
- Department of Ophthalmology, Mayo Clinic School of Medicine, Jacksonville, FL
| | - Syril K. Dorairaj
- Department of Ophthalmology, Mayo Clinic School of Medicine, Jacksonville, FL
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22
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Jiang J, Xu J, Tao Y, Hu C, Zhang C, Sun X, Ye C, Zhang S, Liang Y. A Novel and Reversible Experimental Primate Ocular Hypertension Model: Blocking Schlemm's Canal. Ophthalmic Res 2022; 66:354-366. [PMID: 36380650 DOI: 10.1159/000527099] [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: 03/23/2022] [Accepted: 08/14/2022] [Indexed: 12/23/2023]
Abstract
INTRODUCTION The purpose of this study was to establish a novel and reversible experimental ocular hypertension primate model by blocking Schlemm's canal. METHODS A model was induced in adult cynomolgus monkeys (n = 4) by blocking Schlemm's canal with an inserted microcatheter (200 μm diameter); it was removed 6 weeks later from one monkey to reverse the elevated intraocular hypertension. All animals were monitored for 11 months; weekly measurements of intraocular pressure and biweekly examinations with spectral domain optical coherence tomography and disc photography were performed. Histopathology of the eye and retinal ganglion cell counts were completed at the end of the study. RESULTS The intraocular pressure of the blocked eyes was significantly higher than that of the contralateral eyes at 1 month after the blockage (p < 0.001); the mean intraocular pressure was similar to the contralateral eye from 1 week to 11 months after the microcatheter was removed in monkey A (p = 0.170). The mean intraocular pressure of the blocked eyes of the remaining monkeys was significantly higher than that of the contralateral eyes throughout the follow-up period (p < 0.001). The fundus imaging showed decreases in the retinal nerve fibre layer thickness, and localized defects were observed in two blocked eyes. A histological examination demonstrated that the number of retinal ganglion cells in the blocked eyes of monkeys A, B, and C was significantly decreased compared with the control. CONCLUSION Schlemm's canal blockage alone in the monkey model produces sustained elevation of intraocular pressure, which presents a novel animal model for studying the pathogenesis of glaucoma.
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Affiliation(s)
- Junhong Jiang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
| | - Jing Xu
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
| | - Yan Tao
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
| | - Cheng Hu
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
| | - Cong Zhang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
| | | | - Cong Ye
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
- Glaucoma Institute, Wenzhou Medical University, Wenzhou, China
| | - Shaodan Zhang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
- Glaucoma Institute, Wenzhou Medical University, Wenzhou, China
| | - Yuanbo Liang
- The Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, China
- Glaucoma Institute, Wenzhou Medical University, Wenzhou, China
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23
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Suture trabeculotomy ab interno for secondary glaucoma in Japanese patients with Val30Met hereditary transthyretin amyloidosis. Sci Rep 2022; 12:19330. [PMID: 36369333 PMCID: PMC9652217 DOI: 10.1038/s41598-022-23150-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 10/25/2022] [Indexed: 11/13/2022] Open
Abstract
We retrospectively evaluated surgical outcomes of suture trabeculotomy (SLOT) ab interno for secondary glaucoma in 18 eyes of 12 patients with hereditary transthyretin (ATTRv) amyloidosis with Val30Met mutation. SLOT ab interno was performed between May 2015 and January 2020. All the participants were followed up for at least 12 months. The primary outcome measure was Kaplan-Meier survival. Failure of this treatment was defined as an intraocular pressure (IOP) of ≥ 22 mmHg and a < 20% IOP reduction with or without medication or as additional operations needed to reduce IOP. The mean postoperative follow-up period was 3.5 years (1.2-6.1 years). The SLOT ab interno procedure alone was performed in 17 eyes (94%). Fifteen eyes (83%) had a 360° incision made in Schlemm's canal and 3 eyes (17%) had a 180° incision performed. Cumulative survival values were 0.83, 0.63, and 0.22 at 1, 2, and 3 years, respectively. Ten eyes (56%) needed additional surgery, such as repeated SLOT ab interno, Ahmed glaucoma valve implantation, or MicroPulse transscleral cyclophotocoagulation. Our results here, as well as our previous results with trabeculectomy, suggest that SLOT ab interno may not have a sufficiently long-term effect on secondary glaucoma because of ATTRv amyloidosis.
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24
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Karimi A, Razaghi R, Rahmati SM, Downs JC, Acott TS, Kelley MJ, Wang RK, Johnstone M. The Effect of Intraocular Pressure Load Boundary on the Biomechanics of the Human Conventional Aqueous Outflow Pathway. Bioengineering (Basel) 2022; 9:672. [PMID: 36354583 PMCID: PMC9687513 DOI: 10.3390/bioengineering9110672] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 10/28/2022] [Accepted: 11/08/2022] [Indexed: 09/29/2023] Open
Abstract
BACKGROUND Aqueous humor outflow resistance in the trabecular meshwork (TM), juxtacanalicular connective tissue (JCT), and Schlemm's canal (SC) endothelium of the conventional outflow pathway actively contribute to intraocular pressure (IOP) regulation. Outflow resistance is actively affected by the dynamic outflow pressure gradient across the TM, JCT, and SC inner wall tissues. The resistance effect implies the presence of a fluid-structure interaction (FSI) coupling between the outflow tissues and the aqueous humor. However, the biomechanical interactions between viscoelastic outflow tissues and aqueous humor dynamics are largely unknown. METHODS A 3D microstructural finite element (FE) model of a healthy human eye TM/JCT/SC complex was constructed with elastic and viscoelastic material properties for the bulk extracellular matrix and embedded elastic cable elements. The FE models were subjected to both idealized and a physiologic IOP load boundary using the FSI method. RESULTS The elastic material model for both the idealized and physiologic IOP load boundary at equal IOPs showed similar stresses and strains in the outflow tissues as well as pressure in the aqueous humor. However, outflow tissues with viscoelastic material properties were sensitive to the IOP load rate, resulting in different mechanical and hydrodynamic responses in the tissues and aqueous humor. CONCLUSIONS Transient IOP fluctuations may cause a relatively large IOP difference of ~20 mmHg in a very short time frame of ~0.1 s, resulting in a rate stiffening in the outflow tissues. Rate stiffening reduces strains and causes a rate-dependent pressure gradient across the outflow tissues. Thus, the results suggest it is necessary to use a viscoelastic material model in outflow tissues that includes the important role of IOP load rate.
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Affiliation(s)
- Alireza Karimi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Reza Razaghi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | | | - J. Crawford Downs
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Ted S. Acott
- Departments of Ophthalmology and Biochemistry and Molecular Biology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Mary J. Kelley
- Departments of Ophthalmology and Integrative Biosciences, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Ruikang K. Wang
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Murray Johnstone
- Department of Ophthalmology, University of Washington, Seattle, WA 98195, USA
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25
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Karimi A, Razaghi R, Padilla S, Rahmati SM, Downs JC, Acott TS, Kelley MJ, Wang RK, Johnstone M. Viscoelastic Biomechanical Properties of the Conventional Aqueous Outflow Pathway Tissues in Healthy and Glaucoma Human Eyes. J Clin Med 2022; 11:6049. [PMID: 36294371 PMCID: PMC9605362 DOI: 10.3390/jcm11206049] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/11/2022] [Accepted: 10/12/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Although the tissues comprising the ocular conventional outflow pathway have shown strong viscoelastic mechanical response to aqueous humor pressure dynamics, the viscoelastic mechanical properties of the trabecular meshwork (TM), juxtacanalicular connective tissue (JCT), and Schlemm's canal (SC) inner wall are largely unknown. METHODS A quadrant of the anterior segment from two human donor eyes at low- and high-flow (LF and HF) outflow regions was pressurized and imaged using optical coherence tomography (OCT). A finite element (FE) model of the TM, the adjacent JCT, and the SC inner wall was constructed and viscoelastic beam elements were distributed in the extracellular matrix (ECM) of the TM and JCT to represent anisotropic collagen. An inverse FE-optimization algorithm was used to calculate the viscoelastic properties of the ECM/beam elements such that the TM/JCT/SC model and OCT imaging data best matched over time. RESULTS The ECM of the glaucoma tissues showed significantly larger time-dependent shear moduli compared to the heathy tissues. Significantly larger shear moduli were also observed in the LF regions of both the healthy and glaucoma eyes compared to the HF regions. CONCLUSIONS The outflow tissues in both glaucoma eyes and HF regions are stiffer and less able to respond to dynamic IOP.
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Affiliation(s)
- Alireza Karimi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Reza Razaghi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Steven Padilla
- Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA
| | | | - J. Crawford Downs
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Ted S. Acott
- Departments of Ophthalmology and Biochemistry and Molecular Biology, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Mary J. Kelley
- Departments of Ophthalmology and Integrative Biosciences, Casey Eye Institute, Oregon Health & Science University, Portland, OR 97239, USA
| | - Ruikang K. Wang
- Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA
- Department of Bioengineering, University of Washington, Seattle, WA 98105, USA
| | - Murray Johnstone
- Department of Ophthalmology, University of Washington, Seattle, WA 98109, USA
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26
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Bikuna‐Izagirre M, Aldazabal J, Extramiana L, Moreno‐Montañés J, Carnero E, Paredes J. Technological advances in ocular trabecular meshwork in vitro models for glaucoma research. Biotechnol Bioeng 2022; 119:2698-2714. [PMID: 35836364 PMCID: PMC9543213 DOI: 10.1002/bit.28182] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 05/17/2022] [Accepted: 07/12/2022] [Indexed: 11/13/2022]
Abstract
Glaucoma is the leading cause of irreversible blindness worldwide and is characterized by the progressive degeneration of the optic nerve. Intraocular pressure (IOP), which is considered to be the main risk factor for glaucoma development, builds up in response to the resistance (resistance to what?) provided by the trabecular meshwork (TM) to aqueous humor (AH) outflow. Although the TM and its relationship to AH outflow have remained at the forefront of scientific interest, researchers remain uncertain regarding which mechanisms drive the deterioration of the TM. Current tissue-engineering fabrication techniques have come up with promising approaches to successfully recreate the TM. Nonetheless, more accurate models are needed to understand the factors that make glaucoma arise. In this review, we provide a chronological evaluation of the technological milestones that have taken place in the field of glaucoma research, and we conduct a comprehensive comparison of available TM fabrication technologies. Additionally, we also discuss AH perfusion platforms, since they are essential for the validation of these scaffolds, as well as pressure-outflow relationship studies and the discovery of new IOP-reduction therapies.
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Affiliation(s)
- Maria Bikuna‐Izagirre
- Tecnun School of EngineeringUniversity of NavarraSan SebastiánSpain
- Biomedical Engineering CenterUniversity of NavarraPamplonaSpain
| | - Javier Aldazabal
- Tecnun School of EngineeringUniversity of NavarraSan SebastiánSpain
- Biomedical Engineering CenterUniversity of NavarraPamplonaSpain
| | - Leire Extramiana
- Departamento de oftalmología ClínicaClínica Universidad de NavarraPamplonaEspaña
| | | | - Elena Carnero
- Departamento de oftalmología ClínicaClínica Universidad de NavarraPamplonaEspaña
| | - Jacobo Paredes
- Tecnun School of EngineeringUniversity of NavarraSan SebastiánSpain
- Biomedical Engineering CenterUniversity of NavarraPamplonaSpain
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27
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Mimura T, Noma H, Inoue Y, Kawashima M, Kitsu K, Mizota A. Early Postoperative Effect of Ripasudil Hydrochloride After Trabeculectomy on Secondary Glaucoma: A Randomized Controlled Trial. Open Ophthalmol J 2022. [DOI: 10.2174/18743641-v16-e2206201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Purpose:
To evaluate the effect of Rho-associated kinase inhibitor (ripasudil hydrochloride hydrate; ripasudil) eye drops on postoperative intraocular pressure (IOP) after trabeculectomy in eyes with uveitic glaucoma.
Design:
This was a prospective, observational, controlled, and randomized study.
Methods:
Sixteen eyes of 16 patients with uveitic glaucoma who underwent trabeculectomy without mitomycin C were randomly treated without ripasudil (8 eyes) and with ripasudil (8 eyes). Postoperative IOP and surgical outcomes 3 months after surgery were compared between the two groups.
Results:
No patient discontinued treatment due to the lack of efficacy or adverse effects of ripasudil during the 3-month study period in the ripasudil group. The mean IOP (mmHg) in the control and ripasudil groups were 42.5 ± 9.8 mmHg /43.9 ± 11.7 mmHg (p = 0.82) at baseline, 14.3 ± 4.9 mmHg /9.0 ± 3.7 mmHg (p = 0.04) at 1 week, 16.3 ± 4.2 mmHg /10.6 ± 3.0 mmHg (p = 0.01) at 1 month, and 16.0 ± 3.4 mmHg /12.5 ± 2.3 mmHg (p = 0.04) at 3 months. The number of laser suture lysis procedures (2.0 ± 0.5 vs 0.4 ± 0.7), the rate of bleb revision by needling (50.0% vs 0.0%), and the mean number of antiglaucoma medications (1.6 ± 1.5 vs. 0.1 ± 0.3) after trabeculectomy were higher in the control group than in the ripasudil group (all p < 0.05). A multivariate analysis showed that the IOP reduction rate at 3 months after surgery was associated with the use of ripasudil and baseline IOP (all p < 0.05).
Conclusion:
This study demonstrated the therapeutic efficacy, safety, and tolerability of ripasudil for 3 months postoperatively. Ripasudil may effectively reduce postoperative IOP and increase the success rate of trabeculectomy in patients with uveitic glaucoma.
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28
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Hann CR, Bentley MD, Vercnocke A, Roy Chowdhury U, Fautsch MP. Evaluation of neural innervation in the human conventional outflow pathway distal to Schlemm's canal. Exp Eye Res 2022; 221:109132. [PMID: 35636488 PMCID: PMC10493174 DOI: 10.1016/j.exer.2022.109132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/29/2022] [Accepted: 05/23/2022] [Indexed: 11/26/2022]
Abstract
The distal outflow pathway of the human eye consists of the outer wall of Schlemm's canal, collector channels, and the deep-scleral, mid-scleral and episcleral vessels. It is the last region of transit for aqueous humor before returning to the venous system. While the trabecular meshwork, scleral spur, and inner wall of Schlemm's canal have been extensively analyzed to define their contributions to aqueous outflow, the role of the distal outflow pathway is not completely understood. Collector channels, emanating from Schlemm's canal were previously thought to be passive conduits for aqueous humor. However, recent studies have shown many collector channels contain flap-like appendages which move with changes in pressure. These findings, along with studies demonstrating innervation of episcleral vessels, have led to questions regarding whether other structures in the distal outflow pathway are under neural regulation and how this may influence aqueous humor outflow. This study evaluates the innervation of the outer wall of Schlemm's canal and collector channels, along with the deep-scleral, mid-scleral and episcleral vasculature with microcomputed tomography and 3-dimensional reconstruction, correlative light microscopy, immunohistochemistry, and transmission electron microscopy. Peripheral, autonomic, and sensory nerve fibers were found to be present adjacent to Schlemm's canal outer wall endothelium, collector channel endothelium, and in the different regions of the distal outflow vasculature. Nerves were more commonly identified in regions that contained collector channels when compared to regions without collector channels. These findings regarding the neural anatomy suggest an active neural regulation of aqueous humor outflow throughout the proximal and distal regions of the conventional outflow pathway.
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Affiliation(s)
- Cheryl R Hann
- Department of Ophthalmology, Mayo Clinic, Rochester, MN, USA.
| | | | - Andrew Vercnocke
- Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
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29
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Roy Chowdhury U, Fautsch MP. Isolation and Culture of Vascular Distal Outflow Pathway (VDOP) Cells From Human Donor Eyes. Curr Protoc 2022; 2:e528. [PMID: 36005888 PMCID: PMC9531896 DOI: 10.1002/cpz1.528] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Glaucoma, a progressive neurodegenerative ocular disease, is the leading cause of irreversible blindness worldwide. Elevated intraocular pressure (IOP) is the most common-and the only treatable-risk factor for glaucoma. IOP is generated by the balance between production and removal of aqueous humor in the anterior part of the eye, and the latter happens either through the uveoscleral or the conventional pathway. Although both pathways are important for aqueous humor removal, dysfunction within the conventional pathway is more commonly associated with increased resistance leading to elevated IOP and glaucoma. The conventional pathway can be separated into proximal (trabecular meshwork and inner wall of Schlemm's canal) and distal (outer wall of Schlemm's canal, collector channels, and episcleral vasculature) regions. Both regions contribute resistance to aqueous humor removal, but the proximal region has been studied more extensively due to the availability of model systems. In contrast, little is known about the role of the distal region in outflow resistance, largely due to the lack of suitable in vitro models. To address this, we have developed a novel method of isolating and culturing vascular distal outflow pathway (VDOP) cells from the distal outflow region of human eyes. VDOP cells can be used to study the physiological and molecular functions of cells in the distal outflow region and can help in the development of ocular hypotensive drugs that specifically target this area. We also provide a protocol describing immunohistochemical methods to validate the molecular profile of these cells, utilizing cell surface markers that distinguish them from adjacent cells. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Isolation and culture of VDOP cells Basic Protocol 2: Analysis of cell surface markers.
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Sosnowik S, Swain DL, Fan S, Toris CB, Gong H. Morphological changes to Schlemm's canal and the distal aqueous outflow pathway in monkey eyes with laser-induced ocular hypertension. Exp Eye Res 2022; 219:109030. [PMID: 35283108 PMCID: PMC9133064 DOI: 10.1016/j.exer.2022.109030] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 01/31/2022] [Accepted: 03/06/2022] [Indexed: 11/04/2022]
Abstract
Though roughly 30-50% of aqueous outflow resistance resides distal to Schlemm's canal (SC), the morphology of the conventional outflow pathway distal to SC has not been thoroughly evaluated. This study examined the morphological changes along proximal and distal aspects of the conventional aqueous outflow pathway and their association with decreased outflow facility in an experimental model of glaucoma in cynomolgus macaques. Nd:YAG laser burns were made to 270-340 degrees of the trabecular meshwork (TM) of one eye (n = 6) or both eyes (n = 2) of each monkey to induce ocular hypertension. Distinct regions of the TM were left unlasered. Contralateral eyes (n = 5) were not lasered and were utilized as controls. Monkeys were sacrificed ≥58 months after their last laser treatment. All eyes were enucleated and perfused at 15 mmHg for 30 min to measure outflow facility. Two pairs of eyes were also perfused with fluorescein to examine segmental outflow. All eyes underwent perfusion-fixation for 1 h. Anterior segments were cut into radial wedges and processed for light and electron microscopy. Width, height, and cross-sectional area (CSA) of SC were compared between high- and low-flow regions of control eyes, and between non-lasered regions of laser-treated eyes and control eyes. Number and CSA of intrascleral veins (ISVs) were compared between non-lasered and lasered regions of laser-treated eyes and control eyes, and between high- and low-flow regions of control eyes. Scleral collagen fibril diameter was compared between control eyes and lasered and non-lasered regions of laser-treated eyes. Median outflow facility was significantly decreased in laser-treated eyes compared to control eyes (P = 0.02). Median CSA and height of SC were smaller in high-flow regions than low-flow regions of control eyes (P < 0.05). Median width of SC was not significantly different between high- and low-flow regions of control eyes (P > 0.05). Median CSA, width, and height of SC were not different between non-lasered regions and control eyes (P > 0.05). SC was partially or completely obliterated in lasered regions. Median number of ISVs was significantly decreased in lasered regions compared to non-lasered regions (P < 0.01) and control eyes (P < 0.01). Median CSA of ISVs did not differ between these groups (P > 0.05). Median number and CSA of ISVs were not significantly different between high- and low-flow regions of control eyes (P > 0.05). Lasered regions displayed looser scleral stroma and smaller median diameter of collagen fibrils adjacent to the TM compared to non-lasered regions (P < 0.05) and control eyes (P < 0.05). Dense TM, partial to complete obliteration of SC, and a decreased number of patent ISVs may account in part for the decreased outflow facility in monkey eyes with laser-induced ocular hypertension. The significance of changes in scleral structure in laser-treated eyes warrants further investigation.
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Affiliation(s)
- Shayna Sosnowik
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USA
| | - David L Swain
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USA; Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA
| | - Shan Fan
- Department of Ophthalmology and Visual Science, University of Nebraska Medical Center, Omaha, NE, USA
| | - Carol B Toris
- Department of Ophthalmology and Visual Science, University of Nebraska Medical Center, Omaha, NE, USA; Department of Ophthalmology and Visual Sciences, The Ohio State University, Columbus, OH, USA
| | - Haiyan Gong
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, USA; Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, USA.
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Karimi A, Razaghi R, Rahmati SM, Downs JC, Acott TS, Wang RK, Johnstone M. Modeling the biomechanics of the conventional aqueous outflow pathway microstructure in the human eye. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2022; 221:106922. [PMID: 35660940 PMCID: PMC10424784 DOI: 10.1016/j.cmpb.2022.106922] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/16/2022] [Accepted: 05/26/2022] [Indexed: 05/27/2023]
Abstract
BACKGROUND AND OBJECTIVE Intraocular pressure (IOP) is determined by aqueous humor outflow resistance, which is a function of the combined resistance of Schlemm's canal (SC) endothelium and the trabecular meshwork (TM) and their interactions in the juxtacanalicular connective tissue (JCT) region. Aqueous outflow in the conventional outflow pathway results in pressure gradient across the TM, JCT, and SC inner wall, and induces mechanical stresses and strains that influence the geometry and homeostasis of the outflow system. The outflow resistance is affected by alteration in tissues' geometry, so there is potential for active, two-way, fluid-structure interaction (FSI) coupling between the aqueous humor (fluid) and the TM, JCT, and SC inner wall (structure). However, our understanding of the biomechanical interactions of the aqueous humor with the outflow connective tissues and its contribution to the outflow resistance regulation is incomplete. METHODS In this study, a microstructural finite element (FE) model of a human eye TM, JCT, and SC inner wall was constructed from a segmented, high-resolution histologic 3D reconstruction of the human outflow system. Three different elastic moduli (0.004, 0.128, and 51.5 MPa based on prior reports) were assigned to the TM/JCT complex while the elastic modulus of the SC inner wall was kept constant at 0.00748 MPa. The hydraulic conductivity was programmed separately for the TM, JCT, and SC inner wall using a custom subroutine. Cable elements were embedded into the TM and JCT extracellular matrix to represent the directional stiffness imparted by anisotropic collagen fibril orientation. The resultant stresses and strains in the outflow system were calculated using fluid-structure interaction method. RESULTS The higher TM/JCT stiffness resulted in larger stresses, but smaller strains in the outflow connective tissues, and resulted in a 4- and 5-fold larger pressure drop across the SC inner wall, respectively, compared to the most compliant model. Funneling through µm-sized SC endothelial pores was evident in the models at lower tissue stiffness, but aqueous flow was more turbulent in models with higher TM/JCT stiffness. CONCLUSIONS The mechanical properties of the outflow tissues play a crucial role in the hydrodynamics of the aqueous humor in the conventional outflow system.
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Affiliation(s)
- Alireza Karimi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, 1670 University Boulevard, VH 372B, Birmingham, AL 35294, USA.
| | - Reza Razaghi
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, 1670 University Boulevard, VH 372B, Birmingham, AL 35294, USA
| | | | - J Crawford Downs
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham, 1670 University Boulevard, VH 372B, Birmingham, AL 35294, USA
| | - Ted S Acott
- Ophthalmology and Biochemistry and Molecular Biology, Casey Eye Institute, Oregon Health & Science University, Portland, OR, USA
| | - Ruikang K Wang
- Department of Ophthalmology, University of Washington, Seattle, WA, USA; Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Murray Johnstone
- Department of Ophthalmology, University of Washington, Seattle, WA, USA
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Histological analysis of trabeculotomy - An investigation on the intraocular pressure lowering mechanism. Exp Eye Res 2022; 219:109079. [PMID: 35439528 DOI: 10.1016/j.exer.2022.109079] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 04/09/2022] [Accepted: 04/11/2022] [Indexed: 11/22/2022]
Abstract
The primary aim of trabeculotomy (TLO) and/or minimally invasive glaucoma surgery (MIGS) is to produce a direct communication between the anterior chamber (AC) and collector channels (CC), which is believed to be the process by which intraocular pressure (IOP) is normalized. However, we previously reported our finding of the large opening of the Schlemm's canal (SC) into the AC in eyes with failed TLO (Amari et al., 2015). If the routes from the AC to the CC by TLO/MIGS are direct, IOP should be stabilized at around aqueous vein pressure if the SC and CC are undamaged. However, in eyes in which TLO/MIGS is successful, IOP usually stays at around the middle or high teens post surgery. In this current study, we retrospectively investigated the specific reason for middle- or high-teens IOP following TLO/MIGS via the histological examination of trabeculectomy (TRAB) specimens that include the area of previous TLO/MIGS in eyes with failed TLO or insufficient IOP control following TLO by specifically focusing on the behavior of the SC endothelium (SCE). Patient background, maximum IOP prior to TLO/MIGS and TRAB, the number medications administered, and elapsed time between TLO/MIGS and TRAB were reviewed. In 42 TRAB specimens of 31 120-180° TLO eyes (Group A; 27 ab-externo and 4 ab-interno eyes) and 11 360° suture TLO eyes (Group B), SC length (SCL), the site of the incision in the trabecular meshwork (TM) [i.e., the center (CEN)/anterior-tip (TIP)], and TM opening into the AC [i.e., open (OPN)/closed (CLS)] were histologically investigated. The correlation between the clinical parameters of the maximum IOP of pre-TLO/MIGS, the maximum IOP of pre-TRAB, the percentage of IOP reduction (PIR), and the histological results were statistically evaluated. Our findings revealed a significant negative correlation between the maximum IOP of pre-TRAB and SCL (P = 0.0167), and a significantly higher PIR in the eyes with OPN than those with CLS in Group A (P = 0.0045). However, no significant difference in SCL was found between the OPN and CLS eyes in both groups. In comparison to Group A, a higher percentage of OPN (82%) yet a smaller SCL (P = 0.0024) was observed in Group B. No significant correlation between clinical and histological parameters was found in Group B. In both groups, the common finding was sealing of the SC openings by SC endothelium (SCE) and no direct communication between the AC and the CC. This fact indicates that the nature by which SCE seals off the opened SC lumen into the AC created by TLO may be very important for maintaining the blood-aqueous barrier. Based on these results, we concluded that accessibility for aqueous humor to the SC and preservation of the SC may be important for lowering IOP by TLO. However, the opening of the SC into the AC (OPN type) does not guarantee an adequate IOP lowering effect if the SC is widely collapsed. Thus, TLO may be improved only by eliminating the most resistant part of the TM with minimal SCE damage.
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Gosling D, Wang H, Auger G. Early Results of Irrigating Goniectomy With TrabEx+: A Novel Device for the Treatment of Open-angle Glaucoma. J Glaucoma 2022; 31:268-273. [PMID: 35131982 PMCID: PMC8963515 DOI: 10.1097/ijg.0000000000001994] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 01/19/2022] [Indexed: 12/02/2022]
Abstract
PRCIS Irrigating goniectomy with the TrabEx+ device can lower intraocular pressure (IOP) in patients with glaucoma, as a standalone procedure or combined with cataract surgery. PURPOSE The aim was to describe the efficacy and safety of irrigating goniectomy performed using the TrabEx+ device, either as a standalone procedure or combined with cataract surgery, in eyes with medically treated open-angle glaucoma. METHODS A retrospective case series of eyes treated by a single surgeon at a single UK teaching hospital. Data was collected at follow-up visits at 1 week, 3, 6, 12, 18, and 24 months postoperatively. Primary outcomes included IOP and glaucoma medication reduction after surgery. Proportion of eyes achieving >20% IOP reduction, IOP <21 mm Hg, and no reoperation were classified as surgical success. RESULTS Seventy-three consecutive eyes of 64 patients (mean age 68.4±13.7 y) were enrolled. 62% were treated as combined procedures with cataract surgery. Overall, mean IOP decreased from 31.3±7.3 to 20.9±10.4 mm Hg at the latest follow-up (34% reduction) (P<0.001) at the latest follow-up (16.1±10.3 mo) with mean preoperative medications decreased from 2.9±1.2 to 1.9±1.3 (P<0.001). 73% met the definition of success at latest follow-up. Postoperative complications were recorded including hyphaema (17%), uveitis (3%), hypotony (1%), and persistent vitreous hemorrhage (1%). Eighteen percent required reoperation because of treatment failure. CONCLUSION TrabEx+ appears to be effective in lowering IOP and medication with or without cataract surgery. However, long-term safety and efficacy will be better understood in a prospective study with longer follow-up.
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Jabłońska J, Lewczuk K, Konopińska J, Mariak Z, Rękas M. Microinvasive glaucoma surgery: a review and classification of implant-dependent procedures and techniques. Acta Ophthalmol 2022; 100:e327-e338. [PMID: 33988310 PMCID: PMC9291507 DOI: 10.1111/aos.14906] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 03/08/2021] [Accepted: 04/22/2021] [Indexed: 12/25/2022]
Abstract
The aim of this article is to discuss how physiology and anatomical background affect the effectiveness of implant‐dependent microinvasive glaucoma surgery (MIGS). First, we provide a micro view of aqueous outflow and tissue behaviour. Second, we review studies exploring the mechanisms of the pressure‐lowering effect of MIGS, as well as tissue behaviour during aqueous flow and tissue motion. We also describe and classify microinvasive surgical procedures and the most important types of implants, as well as their mechanisms of action, implantation techniques and efficacy. Further, we summarize the indications and surgical results presented in recent studies, providing an evidence‐based update on novel and emerging MIGS techniques for the treatment of open‐angle glaucoma. These data can help surgeons to personalize the management of glaucoma and to choose the best MIGS option for individual glaucoma patients.
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Affiliation(s)
- Joanna Jabłońska
- Department of Ophthalmology Military Institute of Medicine Warsaw Poland
| | - Katarzyna Lewczuk
- Department of Ophthalmology Military Institute of Medicine Warsaw Poland
| | - Joanna Konopińska
- Department of Ophthalmology Medical University of Bialystok Białystok Poland
| | - Zofia Mariak
- Department of Ophthalmology Medical University of Bialystok Białystok Poland
| | - Marek Rękas
- Department of Ophthalmology Military Institute of Medicine Warsaw Poland
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McDowell CM, Kizhatil K, Elliott MH, Overby DR, van Batenburg-Sherwood J, Millar JC, Kuehn MH, Zode G, Acott TS, Anderson MG, Bhattacharya SK, Bertrand JA, Borras T, Bovenkamp DE, Cheng L, Danias J, De Ieso ML, Du Y, Faralli JA, Fuchshofer R, Ganapathy PS, Gong H, Herberg S, Hernandez H, Humphries P, John SWM, Kaufman PL, Keller KE, Kelley MJ, Kelly RA, Krizaj D, Kumar A, Leonard BC, Lieberman RL, Liton P, Liu Y, Liu KC, Lopez NN, Mao W, Mavlyutov T, McDonnell F, McLellan GJ, Mzyk P, Nartey A, Pasquale LR, Patel GC, Pattabiraman PP, Peters DM, Raghunathan V, Rao PV, Rayana N, Raychaudhuri U, Reina-Torres E, Ren R, Rhee D, Chowdhury UR, Samples JR, Samples EG, Sharif N, Schuman JS, Sheffield VC, Stevenson CH, Soundararajan A, Subramanian P, Sugali CK, Sun Y, Toris CB, Torrejon KY, Vahabikashi A, Vranka JA, Wang T, Willoughby CE, Xin C, Yun H, Zhang HF, Fautsch MP, Tamm ER, Clark AF, Ethier CR, Stamer WD. Consensus Recommendation for Mouse Models of Ocular Hypertension to Study Aqueous Humor Outflow and Its Mechanisms. Invest Ophthalmol Vis Sci 2022; 63:12. [PMID: 35129590 PMCID: PMC8842499 DOI: 10.1167/iovs.63.2.12] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/08/2021] [Indexed: 01/07/2023] Open
Abstract
Due to their similarities in anatomy, physiology, and pharmacology to humans, mice are a valuable model system to study the generation and mechanisms modulating conventional outflow resistance and thus intraocular pressure. In addition, mouse models are critical for understanding the complex nature of conventional outflow homeostasis and dysfunction that results in ocular hypertension. In this review, we describe a set of minimum acceptable standards for developing, characterizing, and utilizing mouse models of open-angle ocular hypertension. We expect that this set of standard practices will increase scientific rigor when using mouse models and will better enable researchers to replicate and build upon previous findings.
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Affiliation(s)
- Colleen M. McDowell
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | | | - Michael H. Elliott
- University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Darryl R. Overby
- Department of Bioengineering, Imperial College London, United Kingdom
| | | | - J. Cameron Millar
- Department of Pharmacology & Neuroscience, and North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Markus H. Kuehn
- Department of Ophthalmology and Visual Sciences and Institute for Vision Research, The University of Iowa; Center for the Prevention and Treatment of Visual Loss, Veterans Affairs Medical Center, Iowa City, Iowa, United States
| | - Gulab Zode
- Department of Pharmacology & Neuroscience, and North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Ted S. Acott
- Ophthalmology and Biochemistry and Molecular Biology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Michael G. Anderson
- Department of Molecular Physiology and Biophysics and Department of Ophthalmology and Visual Sciences, The University of Iowa; Center for the Prevention and Treatment of Visual Loss, Veterans Affairs Medical Center, Iowa City, Iowa, United States
| | | | - Jacques A. Bertrand
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Terete Borras
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
| | | | - Lin Cheng
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States
| | - John Danias
- SUNY Downstate Health Sciences University, Brooklyn, New York, United States
| | - Michael Lucio De Ieso
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Yiqin Du
- Department of Ophthalmology, University of Pittsburgh, Pennsylvania, United States
| | - Jennifer A. Faralli
- Department of Pathology and Laboratory Medicine, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Rudolf Fuchshofer
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Preethi S. Ganapathy
- Department of Ophthalmology and Visual Sciences, SUNY Upstate Medical University, Syracuse, New York, United States
| | - Haiyan Gong
- Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Samuel Herberg
- Department of Ophthalmology and Visual Sciences, SUNY Upstate Medical University, Syracuse, New York, United States
| | | | - Peter Humphries
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland
| | - Simon W. M. John
- Department of Ophthalmology, Columbia University, New York, New York, United States
| | - Paul L. Kaufman
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Kate E. Keller
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Mary J. Kelley
- Department of Ophthalmology and Department of Integrative Biosciences, Oregon Health & Science University, Portland, Oregon, United States
| | - Ruth A. Kelly
- Ocular Genetics Unit, Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland
| | - David Krizaj
- Department of Ophthalmology, University of Utah School of Medicine, Salt Lake City, Utah, United States
| | - Ajay Kumar
- Department of Ophthalmology, University of Pittsburgh, Pennsylvania, United States
| | - Brian C. Leonard
- Department of Surgical and Radiological Sciences, University of California, Davis, Davis, California, United States
| | - Raquel L. Lieberman
- Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, United States
| | - Paloma Liton
- Department of Ophthalmology and Department of Pathology, Duke University, Durham, North Carolina, United States
| | - Yutao Liu
- Department of Cellular Biology and Anatomy, James & Jean Culver Vision Discovery Institute, Augusta University, Augusta, Georgia, United States
| | - Katy C. Liu
- Duke Eye Center, Duke Health, Durham, North Carolina, United States
| | - Navita N. Lopez
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, United States
| | - Weiming Mao
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Timur Mavlyutov
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Fiona McDonnell
- Duke Eye Center, Duke Health, Durham, North Carolina, United States
| | - Gillian J. McLellan
- Department of Surgical Sciences and Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Philip Mzyk
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Andrews Nartey
- College of Optometry, University of Houston, Houston, Texas, United States
| | - Louis R. Pasquale
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, New York, United States
| | - Gaurang C. Patel
- Ophthalmology Research, Regeneron Pharmaceuticals, Tarreytown, New York, United States
| | | | - Donna M. Peters
- Department of Pathology and Laboratory Medicine, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | | | - Ponugoti Vasantha Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
| | - Naga Rayana
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Urmimala Raychaudhuri
- Department of Neurobiology, University of California, Irvine, Irvine, California, United States
| | - Ester Reina-Torres
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Ruiyi Ren
- Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Douglas Rhee
- Case Western Reserve University School of Medicine, Cleveland, Ohio, United States
| | - Uttio Roy Chowdhury
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States
| | - John R. Samples
- Washington State University, Floyd Elson College of Medicine, Spokane, Washington, United States
| | | | - Najam Sharif
- Santen Inc., Emeryville, California, United States
| | - Joel S. Schuman
- Department of Ophthalmology and Department of Physiology and Neuroscience, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States; Departments of Biomedical Engineering and Electrical and Computer Engineering, New York University Tandon School of Engineering, Brooklyn, New York, United States; Center for Neural Science, College of Arts and Science, New York University, New York, New York, United States
| | - Val C. Sheffield
- Department of Pediatrics and Department of Ophthalmology and Visual Sciences, University of Iowa Carver College of Medicine, Iowa City, Iowa, United States
| | - Cooper H. Stevenson
- Department of Pharmacology & Neuroscience, and North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Avinash Soundararajan
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | | | - Chenna Kesavulu Sugali
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Yang Sun
- Veterans Affairs Palo Alto Health Care System, Stanford University, Palo Alto, California, United States
| | - Carol B. Toris
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, Nebraska, United States; Department of Ophthalmology and Vision Sciences, The Ohio State University, Columbus, Ohio, United States
| | | | - Amir Vahabikashi
- Cell and Developmental Biology Department, Northwestern University, Chicago, Illinois, United States
| | - Janice A. Vranka
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Ting Wang
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Colin E. Willoughby
- Genomic Medicine, Biomedical Sciences Research Institute, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Chen Xin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Hongmin Yun
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Hao F. Zhang
- Biomedical Engineering Department, Northwestern University, Evanston, Illinois, United States
| | - Michael P. Fautsch
- Biomedical Engineering Department, Northwestern University, Evanston, Illinois, United States
| | | | - Abbot F. Clark
- Department of Pharmacology and Neuroscience, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - C. Ross Ethier
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology; Emory University School of Medicine, Emory University, Atlanta, Georgia, United States
| | - W. Daniel Stamer
- Duke Ophthalmology, Duke University, Durham, North Carolina, United States
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Mori S, Murai Y, Ueda K, Sakamoto M, Kurimoto T, Yamada‐Nakanishi Y, Nakamura M. Comparison of efficacy and early surgery-related complications between one-quadrant and two-quadrant microhook ab interno trabeculotomy: a propensity score matched study. Acta Ophthalmol 2021; 99:898-903. [PMID: 33576191 DOI: 10.1111/aos.14787] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 01/18/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE We compared the 1-year outcomes and early surgery-related complications between 1-quadrant and 2-quadrant microhook ab interno trabeculotomy (TLO). METHODS Medical chart extraction was performed on 47 consecutive patients with 1-quadrant incision and 37 consecutive patients with 2-quadrant incision of trabecular meshwork. Logistic regression analysis was conducted to calculate the propensity score to create a 1:1 match for a comparative analysis of 1-year postoperative success. Success was defined as postoperative intraocular pressure (IOP) between 5-21 mmHg, >20% IOP reduction from baseline, and no additional glaucoma surgery. Outcome-related covariates were age, glaucoma type, mean deviation of visual field tests, preoperative IOP, the number of preoperative glaucoma eye drops and the presence of combined cataract surgery. Thirty eyes from each group were compared. RESULTS The median preoperative IOP was not different between the 1-quadrant and 2-quadrant groups (28.5 mmHg, quartile range 23-33.5 versus 27 mmHg, 23.3-30.0, p = 0.47). There was no difference in median postoperative IOP at 1 year (15 mmHg versus 16 mmHg, p = 0.80). The success rate was 73% in the 1-quadrant group versus 70% in the 2-quadrant group (p = 1.00). The 2-quadrant group had a significantly higher proportion of patients with transiently elevated IOP (47%) than the 1-quadrant (17%; Fisher's exact test, p = 0.02). There was no difference of hyphema formation (Fisher's exact test, p = 0.18). CONCLUSION The 1-year success rate was not significantly different between 1- and 2-quadrant incisions of microhook TLO. However, the 2-quadrant TLO showed significantly higher proportion of post-surgical transient IOP elevation.
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Affiliation(s)
- Sotaro Mori
- Department of Surgery Division of Ophthalmology Kobe University Graduate School of Medicine Kobe Japan
| | - Yusuke Murai
- Department of Surgery Division of Ophthalmology Kobe University Graduate School of Medicine Kobe Japan
| | - Kaori Ueda
- Department of Surgery Division of Ophthalmology Kobe University Graduate School of Medicine Kobe Japan
| | - Mari Sakamoto
- Department of Surgery Division of Ophthalmology Kobe University Graduate School of Medicine Kobe Japan
| | - Takuji Kurimoto
- Department of Surgery Division of Ophthalmology Kobe University Graduate School of Medicine Kobe Japan
| | - Yuko Yamada‐Nakanishi
- Department of Surgery Division of Ophthalmology Kobe University Graduate School of Medicine Kobe Japan
| | - Makoto Nakamura
- Department of Surgery Division of Ophthalmology Kobe University Graduate School of Medicine Kobe Japan
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Dada T, Mahalingam K, Bhartiya S. Minimally Invasive Glaucoma Surgery-to Remove or Preserve the Trabecular Meshwork: That is the Question? J Curr Glaucoma Pract 2021; 15:47-51. [PMID: 34720492 PMCID: PMC8543745 DOI: 10.5005/jp-journals-10078-1299] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
How to cite this article: Dada T, Mahalingam K, Bhartiya S. Minimally Invasive Glaucoma Surgery—to Remove or Preserve the Trabecular Meshwork: That is the Question? J Curr Glaucoma Pract 2021;15(2):47–51.
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Affiliation(s)
- Tanuj Dada
- Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Karthikeyan Mahalingam
- Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Shibal Bhartiya
- Department of Ophthalmology, Glaucoma Services, Fortis Memorial Hospital, Gurugram, Haryana, India
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Identification of Estrogen Signaling in a Prioritization Study of Intraocular Pressure-Associated Genes. Int J Mol Sci 2021; 22:ijms221910288. [PMID: 34638643 PMCID: PMC8508848 DOI: 10.3390/ijms221910288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 12/12/2022] Open
Abstract
Elevated intraocular pressure (IOP) is the only modifiable risk factor for primary open-angle glaucoma (POAG). Herein we sought to prioritize a set of previously identified IOP-associated genes using novel and previously published datasets. We identified several genes for future study, including several involved in cytoskeletal/extracellular matrix reorganization, cell adhesion, angiogenesis, and TGF-β signaling. Our differential correlation analysis of IOP-associated genes identified 295 pairs of 201 genes with differential correlation. Pathway analysis identified β-estradiol as the top upstream regulator of these genes with ESR1 mediating 25 interactions. Several genes (i.e., EFEMP1, FOXC1, and SPTBN1) regulated by β-estradiol/ESR1 were highly expressed in non-glaucomatous human trabecular meshwork (TM) or Schlemm’s canal (SC) cells and specifically expressed in TM/SC cell clusters defined by single-cell RNA-sequencing. We confirmed ESR1 gene and protein expression in human TM cells and TM/SC tissue with quantitative real-time PCR and immunofluorescence, respectively. 17β-estradiol was identified in bovine, porcine, and human aqueous humor (AH) using ELISA. In conclusion, we have identified estrogen receptor signaling as a key modulator of several IOP-associated genes. The expression of ESR1 and these IOP-associated genes in TM/SC tissue and the presence of 17β-estradiol in AH supports a role for estrogen signaling in IOP regulation.
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Okamoto Y, Akagi T, Kameda T, Suda K, Miyake M, Ikeda HO, Numa S, Kadomoto S, Uji A, Tsujikawa A. Prediction of trabecular meshwork-targeted micro-invasive glaucoma surgery outcomes using anterior segment OCT angiography. Sci Rep 2021; 11:17850. [PMID: 34497321 PMCID: PMC8426381 DOI: 10.1038/s41598-021-97290-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 08/19/2021] [Indexed: 02/07/2023] Open
Abstract
We performed a prospective, longitudinal study to investigate the association between the preoperative intrascleral vasculature assessed using anterior segment (AS)-optical coherence tomography angiography (OCTA) and surgical outcomes of trabecular meshwork-targeted micro- or minimally invasive glaucoma surgery (MIGS). We included 37 patients with primary open-angle glaucoma. Preoperative AS-OCTA images of the sclero-conjunctiva of the nasal corneal limbus were acquired in the superficial (conjunctival) and deep (intrascleral) layers. The vessel densities (VDs) of each layer were measured separately in the entire area, limbal side, and fornix area. Surgical success was determined by postoperative intraocular pressure (IOP) and IOP reduction. Twenty-three and 14 eyes were classified as having successful and unsuccessful outcomes, respectively. The deep VDs of the entire area and fornix area were significantly lower in the successful group (P = 0.031 and P = 0.009). The success rate was significantly higher for eyes with a lower deep VD than for eyes with a higher deep VD. A greater IOP reduction was significantly associated with lower deep VD in the fornix area (P = 0.022) and higher preoperative IOP (P < 0.001). These results indicate that intrascleral vasculature assessed using preoperative AS-OCTA was negatively correlated with surgical success and IOP reduction resulting from trabecular meshwork-targeted MIGS. AS-OCTA images might help predict MIGS outcomes.
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Affiliation(s)
- Yoko Okamoto
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tadamichi Akagi
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan ,grid.260975.f0000 0001 0671 5144Division of Ophthalmology and Visual Science, Niigata University Graduate School of Medical and Dental Sciences, 1-757, Asahimachi-dori, Chuo-ku, Niigata, 951-8510 Japan
| | - Takanori Kameda
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Kenji Suda
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masahiro Miyake
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Hanako Ohashi Ikeda
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Shogo Numa
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Shin Kadomoto
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Akihito Uji
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Akitaka Tsujikawa
- grid.258799.80000 0004 0372 2033Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
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Characteristics of glaucoma patients with intraocular pressure elevation early after trabectome surgery. Graefes Arch Clin Exp Ophthalmol 2021; 260:537-543. [PMID: 34468832 DOI: 10.1007/s00417-021-05355-1] [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: 04/01/2021] [Revised: 07/10/2021] [Accepted: 07/27/2021] [Indexed: 10/20/2022] Open
Abstract
PURPOSE To analyze the rate and time of occurrence of intraocular pressure (IOP) elevation early after trabectome surgery (TOM) and the characteristics of glaucoma patients recovering from IOP elevation. METHOD Four hundred sixty eyes of 460 glaucoma (191 primary and 269 secondary open-angle glaucoma) patients who underwent TOM were evaluated. IOP elevation early after TOM was diagnosed when IOP increased by more than 5 mmHg over baseline within 1 week to 3 months. If the IOP decreased with the administration of anti-glaucoma eye drops alone, patients were classified as recovered. If the IOP did not decrease despite additional anti-glaucoma eye drop use, patients were classified as non-recovered. The rate and time of occurrence of IOP elevation early after TOM were investigated. Demographic and ocular variables related to recovery and non-recovery were identified by multivariate logistic regression analysis. RESULTS Of the 460 patients, IOP elevation early after TOM occurred in 102 (22.2%). IOP elevation occurred most frequently at postoperative week 1. Of the 102 patients with IOP elevation, 55 (53.9%) recovered and 47 (46.1%) did not. A large hyphema size the day after surgery was associated with increased likelihood of recovery from IOP elevation (odds ratio [OR], 6.6). A history of past selective laser trabeculoplasty (SLT; OR, 0.10) and high baseline IOP (OR, 0.86) were associated with reduced likelihood of recovery from IOP elevation. CONCLUSION IOP elevation early after TOM occurred most frequently at postoperative week 1. Patients with a large hyphema size, no history of SLT, and a lower baseline IOP recovered from IOP elevation early after TOM. A large hyphema the day after surgery suggested an increased likelihood of recovery from IOP elevation.
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Yokoyama H, Takata M, Gomi F. One-year outcomes of microhook trabeculotomy versus suture trabeculotomy ab interno. Graefes Arch Clin Exp Ophthalmol 2021; 260:215-224. [PMID: 34338846 PMCID: PMC8763744 DOI: 10.1007/s00417-021-05333-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 07/11/2021] [Accepted: 07/15/2021] [Indexed: 11/30/2022] Open
Abstract
Purpose To compare clinical success rates and reductions in intraocular pressure (IOP) and IOP-lowering medication use following suture trabeculotomy ab interno (S group) or microhook trabeculotomy (μ group). Methods This retrospective review collected data from S (n = 104, 122 eyes) and μ (n = 42, 47 eyes) groups who underwent treatment between June 1, 2016, and October 31, 2019, and had 12-month follow-up data including IOP, glaucoma medications, complications, and additional IOP-lowering procedures. The Kaplan–Meier survival analysis was used to evaluate treatment success rates defined as normal IOP (> 5 to ≤ 18 mm Hg), ≥ 20% reduction of IOP from baseline at two consecutive visits, and no further glaucoma surgery. Results Schlemm’s canal opening was longer in the S group than in the μ group (P < 0.0001). The Kaplan–Meier survival analysis of all eyes showed cumulative clinical success rates in S and µ groups were 71.1% and 61.7% (P = 0.230). The Kaplan–Meier survival analysis of eyes with preoperative IOP ≥ 21 mmHg showed cumulative clinical success rates in S and μ groups were 80.4% and 60.0% (P = 0.0192). There were no significant differences in postoperative IOP at 1, 3, and 6 months (S group, 14.9 ± 5.6, 14.6 ± 4.5, 14.6 ± 3.9 mmHg; μ group, 15.8 ± 5.9, 15.2 ± 4.4, 14.7 ± 3.7 mmHg; P = 0.364, 0.443, 0.823), but postoperative IOP was significantly lower in the S group at 12 months (S group, 14.1 ± 3.1 mmHg; μ group, 15.6 ± 4.1 mmHg; P = 0.0361). There were no significant differences in postoperative numbers of glaucoma medications at 1, 3, 6, and 12 months (S group, 1.8 ± 1.6, 1.8 ± 1.5, 2.0 ± 1.6, 1.8 ± 1.5; μ group, 2.0 ± 1.6, 2.0 ± 1.6, 2.1 ± 1.6, 2.2 ± 1.7; P = 0.699, 0.420, 0.737, 0.198). Conclusion S and µ group eyes achieved IOP reduction, but μ group eyes had lower clinical success rates among patients with high preoperative IOP at 12 months. ![]()
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Affiliation(s)
- Hiroshi Yokoyama
- Department of Ophthalmology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo, 663-8501, Japan
| | - Masashi Takata
- Department of Ophthalmology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo, 663-8501, Japan.
| | - Fumi Gomi
- Department of Ophthalmology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo, 663-8501, Japan
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Hamanaka T, Sakurai T, Fuse N, Ishida N, Kumasaka T, Tanito M. Comparisons of Schlemm's canal and trabecular meshwork morphologies between juvenile and primary open angle glaucoma. Exp Eye Res 2021; 210:108711. [PMID: 34352267 DOI: 10.1016/j.exer.2021.108711] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 07/20/2021] [Accepted: 07/27/2021] [Indexed: 11/30/2022]
Abstract
The histologic differences in Schlemm's canal (SC) and trabecular meshwork (TM), obtained from the trabeculectomy specimens of different age-group glaucoma patients, were compared. This study involved 44 trabeculectomy specimens of 37 juvenile-onset open-angle glaucoma (JOAG) patients (Group A) and 24 trabeculectomy specimens of 24 elderly-onset primary OAG (POAG) patients (age range: 70-79 years, Group B) with no familial history of POAG. Clinical parameters of gender, maximum intraocular pressure (IOP), and the number of glaucoma medications used prior to trabeculectomy were investigated and compared between the two groups. From light microscopy photographs of hematoxylin-eosin, and immunohistochemical staining of markers for SC endothelium (SCE), the total SC length (TSC), comprised of the opened-SC length (OSC) and the closed-SC length (CSC), the percentage of CSC in TSC (%CSC), the percentage of positive SCE marker in CSC (%PinCSC), and the percentage of negative SCE marker in OSC (%NinOSC) were analyzed. Moreover, podoplanin staining patterns in the TM were investigated and compared between the two groups. Among the clinical parameters, the mean maximum IOP in Group A (33.41 ± 9.24 mmHg) was the only significant parameter when compared to that in Group B (22.96 ± 7.17 mmHg, P = 0.000003). TSC in Group A was significantly shorter than that in Group B (P = 0.00092), and %CSC (P = 0.00004) and %PinCSC (P = 0.00342) in Group B were significantly higher than those in Group A. No statistically significant difference in %NinOSC was found between Group A and Group B (P = 0.76060). Juxtacanalicular tissue (JCT) in Group A showed compact and weak staining with podoplanin, while the JCT and closed-SC area in Group B showed intense staining. In the Group A subjects, TSC (P = 0.04819) and OSC (P = 0.02867) were significantly shorter in the non-familial cases than in the familial cases. Platelet coagulations 10-37 μm in size at the defect of the SCE in the inner wall of the SC were observed in 8 eyes (18%) and 4 eyes (17%) in Group A and Group B, respectively. The platelets appeared to repair the SCE damage for maintaining the blood aqueous barrier in both groups of POAG eyes. Smaller SC diameters and accompanying TM abnormality were features observed in the young-onset JOAG patients, thus suggesting developmental abnormalities in the outflow routes. The collapse of SC lumen, presumably due to aging, was the feature observed in the elderly-onset POAG patients. In Group A, the significantly higher IOP, despite of no significant number of topical medications used prior to trabeculectomy, also suggested that JOAG eyes can be categorized as a distinct type of POAG from the eyes of elder-aged POAG patients. The SCE drop out observed in the glaucomatous eyes of the different age groups suggested that worsening of IOP control may possibly occur equally in both groups.
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Affiliation(s)
- Teruhiko Hamanaka
- Department of Ophthalmology, Japanese Red Cross Medical Center, Shibuya-Ku, Tokyo, Japan; Department of Ophthalmology, Ishida Eye Clinic, Joetsu, Japan.
| | - Tetsuro Sakurai
- School of General and Management Studies, Suwa University of Science, Suwa, Japan
| | - Nobuo Fuse
- Tohoku Medical Megabank Organization, Tohoku University, Sendai, Japan
| | - Nobuo Ishida
- Department of Ophthalmology, Ishida Eye Clinic, Joetsu, Japan
| | - Toshio Kumasaka
- Department of Pathology, Japanese Red Cross Medical Center, Tokyo, Japan
| | - Masaki Tanito
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo, Japan
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Effects of Preoperative Intraocular Pressure Level on Surgical Results of Microhook Ab Interno Trabeculotomy. J Clin Med 2021; 10:jcm10153327. [PMID: 34362110 PMCID: PMC8348769 DOI: 10.3390/jcm10153327] [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: 07/05/2021] [Revised: 07/26/2021] [Accepted: 07/26/2021] [Indexed: 11/17/2022] Open
Abstract
To assess the roles of preoperative intraocular pressure (IOP) level on the IOP reducing efficacy of microhook ab interno trabeculotomy (µLOT), 126 consecutive open-angle glaucomatous eyes (90 primary open angle glaucoma, 36 exfoliation glaucoma) of 126 Japanese subjects (60 men, 66 women; mean age ± standard deviation, 70.5 ± 11.4 years) who underwent µLOT alone (25 eyes, 20%) or combined µLOT and cataract surgery (101 eyes, 80%) were retrospectively included, and subdivided into four groups based on the quartile of preoperative IOP: Q1, ≤15 mmHg; Q2, 15–18 mmHg, Q3, 18–21 mmHg, and Q4, >21 mmHg. Preoperative and 12 months postoperative IOPs and numbers of antiglaucoma medications were compared among IOP groups. Factors associated with postoperative IOP were assessed using multivariate analysis, and the success of IOP control was assessed with various definitions. Postoperatively, IOP was significantly higher in Q3 (p < 0.0146) and Q4 (p = 0.0320) groups than Q1 group, while the number of medications was not significantly different among four IOP groups (p = 0.1966). Older age was associated with lower postoperative IOP, and higher preoperative IOP was associated with higher postoperative IOP, while sex, glaucoma type, surgical procedure, lens status, extent of trabeculotomy incision, and preoperative number of medications were not associated with postoperative IOP. The success rates for IOP ≤ 18 and ≤15 mmHg were higher in lower preoperative IOP groups (i.e., Q1 and Q2) than higher preoperative IOP groups (Q3 and Q4), while the success rate for ≥20% IOP reduction was higher in higher preoperative IOP groups than in lower preoperative IOP groups; the success rate for ≥0% IOP reduction was equivalent among groups. By reviewing the previous studies in ab interno trabeculotomy/goniotomy procedures, positive correlation between preoperative and postoperative IOPs was preserved throughout the studies and surgical procedures. After the µLOT, larger %IOP reduction was achieved in higher preoperative IOP groups than in lower preoperative IOP groups, while postoperative IOP was still lower than in lower preoperative IOP groups.
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Okada N, Hirooka K, Onoe H, Murakami Y, Okumichi H, Kiuchi Y. Comparison of Efficacy between 120° and 180° Schlemm's Canal Incision Microhook Ab Interno Trabeculotomy. J Clin Med 2021; 10:3181. [PMID: 34300347 PMCID: PMC8304718 DOI: 10.3390/jcm10143181] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/09/2021] [Accepted: 07/17/2021] [Indexed: 11/25/2022] Open
Abstract
We compared surgical outcomes in patients with either primary open-angle glaucoma or exfoliation glaucoma after undergoing combined phacoemulsification with either a 120° or 180° incision during a Schlemm's canal microhook ab interno trabeculotomy (μLOT-Phaco). This retrospective comparative case series examined 52 μLOT-Phaco eyes that underwent surgery between September 2017 and December 2020. Surgical qualified success was defined as an intraocular pressure (IOP) of ≤20 mmHg, ≥20% IOP reduction with IOP-lowering medications, and no additional glaucoma surgery. Success rates were evaluated by Kaplan-Meier survival analysis. The number of postoperative IOP-lowering medications and occurrence of complications were also assessed. Mean preoperative IOP in the 120° group was 16.9 ± 7.6 mmHg, which significantly decreased to 10.9 ± 2.7 mmHg (p < 0.01) and 11.1 ± 3.1 mmHg (p = 0.01) at 12 and 24 months, respectively. The mean number of preoperative IOP-lowering medications significantly decreased from 2.8 ± 1.4 to 1.4 ± 1.4 (p < 0.01) at 24 months. Mean preoperative IOP in the 180° group was 17.1 ± 7.0 mmHg, which significantly decreased to 12.1 ± 3.2 mmHg (p = 0.02) and 12.9 ± 1.4 mmHg (p = 0.01) at 12 and 24 months, respectively. The mean number of preoperative IOP-lowering medications significantly decreased from 2.9 ± 1.2 to 1.4 ± 1.5 (p < 0.01) at 24 months. The probability of qualified success at 24 months in the 120° and 180° groups was 50.4% and 54.6%, respectively (p = 0.58). There was no difference observed for hyphema formation or IOP spikes. Surgical outcomes were not significantly different between the 120° and 180° incisions in Schlemm's canal.
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Affiliation(s)
| | - Kazuyuki Hirooka
- Department of Ophthalmology and Visual Science, Hiroshima University, Hiroshima 734-8551, Japan; (N.O.); (H.O.); (Y.M.); (H.O.); (Y.K.)
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Farrar N, Yan DB, Johnson M. Modeling the effects of glaucoma surgery on intraocular pressure. Exp Eye Res 2021; 209:108620. [PMID: 34048778 DOI: 10.1016/j.exer.2021.108620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 04/13/2021] [Accepted: 05/10/2021] [Indexed: 11/27/2022]
Abstract
Minimally invasive glaucoma surgeries (MIGS) offer an effective way to lower intraocular pressure without inducing extensive trauma to the anterior segment. In order to predict their efficacy, an analytical model of the conventional aqueous humor outflow pathway is developed using a resistor network. The model describes outflow through the normal eye and allows for the effects of geometric changes in the outflow pathway as IOP changes. By selectively removing these resistors, the model can be used to examine and predict the outcomes of several surgical procedures currently used to treat glaucoma. Treatments examined include traditional trabeculectomy, several ab interno methods for trabeculotomy and trabeculectomy, as well as recently developed trabecular stents that bypass the trabecular meshwork and dilate Schlemm canal. The model's predictions for the efficacy of these procedures generally matched well with the efficacy determined in experimental studies, although it tended to somewhat overestimate the efficacy of these procedures. Matching the model to experimental data indicated that a partial trabeculotomy substantially increases flow to collector channels within that region and approximately 1.5 clock hours past the ends of the trabeculotomized region. Similarly, trabecular bypass stents substantially increase flow to collector channels up to 1.5 clock hours past the open ends of the stent. The resistor model we have developed can be used to predict the efficacy of a variety of MIGS procedures. Circumferential flow in Schlemm canal extends the efficacy of MIGS, but this effect is limited to a few clock hours.
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Affiliation(s)
- Nicholas Farrar
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, E310, Evanston, IL 60208, USA
| | - David B Yan
- Department of Ophthalmology and Vision Sciences, University of Toronto, 340 College Street, Suite 400, Toronto, ON. M5T 3A9, Canada
| | - Mark Johnson
- Department of Biomedical Engineering, Northwestern University, 2145 Sheridan Road, E310, Evanston, IL 60208, USA; Department of Mechanical Engineering, Northwestern University, 2145 Sheridan Road, Room B224, Evanston, IL 60208, USA; Department of Ophthalmology, Northwestern University, 645 N. Michigan Ave. Suite 440, Chicago, IL 60611, USA.
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Toris CB, Gagrani M, Ghate D. Current methods and new approaches to assess aqueous humor dynamics. EXPERT REVIEW OF OPHTHALMOLOGY 2021. [DOI: 10.1080/17469899.2021.1902308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Carol B. Toris
- Dept. Of Ophthalmology and Visual Science, University of Nebraska Medical Center, Omaha, NE, USA
- Dept. Of Ophthalmology and Visual Science, Case Western Reserve University, Cleveland, OH USA
| | - Meghal Gagrani
- Dept. Of Ophthalmology and Visual Science, University of Nebraska Medical Center, Omaha, NE, USA
| | - Deepta Ghate
- Dept. Of Ophthalmology and Visual Science, University of Nebraska Medical Center, Omaha, NE, USA
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De Ieso ML, Gurley JM, McClellan ME, Gu X, Navarro I, Li G, Gomez-Caraballo M, Enyong E, Stamer WD, Elliott MH. Physiologic Consequences of Caveolin-1 Ablation in Conventional Outflow Endothelia. Invest Ophthalmol Vis Sci 2021; 61:32. [PMID: 32940661 PMCID: PMC7500130 DOI: 10.1167/iovs.61.11.32] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Purpose Polymorphisms at the caveolin-1/2 locus are associated with glaucoma and IOP risk and deletion of caveolin-1 (Cav1) in mice elevates IOP and reduces outflow facility. However, the specific location/cell type responsible for Cav1-dependent regulation of IOP is unclear. We hypothesized that endothelial Cav1 in the conventional outflow (CO) pathway regulate IOP via endothelial nitric oxide synthase (eNOS) signaling. Methods We created a mouse with targeted deletion of Cav1 in endothelial cells (Cav1ΔEC) and evaluated IOP, outflow facility, outflow pathway distal vascular morphology, eNOS phosphorylation, and tyrosine nitration of iridocorneal angle tissues by Western blotting. Results Endothelial deletion of Cav1 resulted in significantly elevated IOP versus wild-type mice but not a concomitant decrease in outflow facility. Endothelial Cav1 deficiency did not alter the trabecular meshwork or Schlemm's canal morphology, suggesting that the effects observed were not due to developmental deformities. Endothelial Cav1 deletion resulted in eNOS hyperactivity, modestly increased protein nitration, and significant enlargement of the drainage vessels distal to Schlemm's canal. L-Nitro-arginine methyl ester treatment reduced outflow in Cav1ΔEC but not wild-type mice and had no effect on the size of drainage vessels. Endothelin-1 treatment decrease the outflow and drainage vessel size in both wild-type and Cav1ΔEC mice. Conclusions Our results suggest that hyperactive eNOS signaling in the CO pathway of both Cav1ΔEC and global Cav1 knockout mice results in chronic dilation of distal CO vessels and protein nitration, but that Cav1 expression in the trabecular meshwork is sufficient to rescue CO defects reported in global Cav1 knockout mice.
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Affiliation(s)
- Michael L De Ieso
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Jami M Gurley
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Mark E McClellan
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Xiaowu Gu
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Iris Navarro
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Guorong Li
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Maria Gomez-Caraballo
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Eric Enyong
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - W Daniel Stamer
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Michael H Elliott
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States.,Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
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48
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Konopińska J, Lewczuk K, Jabłońska J, Mariak Z, Rękas M. Microinvasive Glaucoma Surgery: A Review of Schlemm's Canal-Based Procedures. Clin Ophthalmol 2021; 15:1109-1118. [PMID: 33737802 PMCID: PMC7961128 DOI: 10.2147/opth.s293702] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 02/18/2021] [Indexed: 12/12/2022] Open
Abstract
Microinvasive glaucoma surgery has gained popularity over the past decade. It can be performed using three different mechanisms. In the present review, we focused on Schlemm’s canal (SC)-based surgery, which increases aqueous humor (AH) outflow into the aqueous veins by either removal of the trabecular meshwork (TM) or an increase in the tension in the TM. In primary open-angle glaucoma (POAG), the TM is the most likely region for increased AH outflow resistance. Theoretically, removal of the TM can improve the AH outflow; hence, glaucoma specialists focus on microsurgical dissection of the TM. In this review, we analyzed the available literature to examine SC-related microsurgical modalities based on the histopathological proofs of the localization of resistance of the AH outflow. First, we considered the role, anatomy, and physiology of the TM and SC. We referred to studies that describe the mechanisms and potential pathways, related to increased intraocular pressure in the POAG, that are targeted using the SC-related microsurgical interventions. Next, we took a closer look at the gonioscopic tools necessary for an ab-interno approach and explored incision canal surgery: ab-interno trabeculectomy using different instrumentation (Trabectome®, Kahook Dual Blade) and variations of the technique. Thereafter, we discussed ab-interno canaloplasty, explaining the technique and reviewing its effectiveness. Finally, we presented the scope for future research in the field. Although the iStent also targets SC by bypassing it, this device has been reviewed extensively elsewhere.
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Affiliation(s)
- Joanna Konopińska
- Department of Ophthalmology, Medical University of Bialystok, Białystok, Poland
| | - Katarzyna Lewczuk
- Department of Ophthalmology, Military Institute of Medicine, Warsaw, Poland
| | - Joanna Jabłońska
- Department of Ophthalmology, Military Institute of Medicine, Warsaw, Poland
| | - Zofia Mariak
- Department of Ophthalmology, Medical University of Bialystok, Białystok, Poland
| | - Marek Rękas
- Department of Ophthalmology, Military Institute of Medicine, Warsaw, Poland
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49
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Roy Chowdhury U, Bahler CK, Hann CR, Holman BH, Fautsch MP. Isolation and characterization of novel primary cells from the human distal outflow pathway. Sci Rep 2021; 11:4034. [PMID: 33597641 PMCID: PMC7890058 DOI: 10.1038/s41598-021-83558-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 02/01/2021] [Indexed: 12/01/2022] Open
Abstract
Ocular hypertension occurs due to increased resistance to aqueous humor removal through the conventional outflow pathway. Unlike the proximal region of the conventional outflow pathway, the distal region has not been well studied, mostly due to lack of model systems. Here we describe isolation and characterization of human primary vascular distal outflow pathway (VDOP) cells from the distal region of the conventional outflow pathway. Tissue from the distal region was isolated from human corneo-scleral rims, digested with collagenase type I (100 U/ml) and placed on gelatin coated plates to allow cellular growth in Dulbecco's Modified Eagle's Medium (low glucose) containing fetal bovine serum and antibiotic/antimycotic. VDOP cells showed consistent proliferation for up to 7 passages, retained endothelial-like nature of the parent tissues and showed a unique marker phenotype of Lectin+VEGFR2-CD34-NG2- that was distinct from neighboring trabecular meshwork (Lectin+VEGFR2-CD34-NG2+) and Schlemm's canal (Lectin+VEGFR2+CD34+NG2+) cells. Dexamethasone treated VDOP cells did not express myocilin and did not form cross-linked actin networks, in contrast to trabecular meshwork cells. These data show that VDOP cells are unique to the distal outflow region and can be used as a viable in vitro model system to understand the biology of the distal outflow pathway and intraocular pressure regulation.
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Affiliation(s)
- Uttio Roy Chowdhury
- Department of Ophthalmology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA.
| | - Cindy K Bahler
- Department of Ophthalmology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Cheryl R Hann
- Department of Ophthalmology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Bradley H Holman
- Department of Ophthalmology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
| | - Michael P Fautsch
- Department of Ophthalmology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, USA
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50
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Midterm Results of Microhook ab Interno Trabeculotomy in Initial 560 Eyes with Glaucoma. J Clin Med 2021; 10:jcm10040814. [PMID: 33671386 PMCID: PMC7922585 DOI: 10.3390/jcm10040814] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 12/19/2022] Open
Abstract
All the 560 glaucomatous eyes of 375 Japanese subjects (181 men, 194 women; mean age ± standard deviation, 76.0 ± 13.2 years) who underwent microhook ab interno trabeculotomy (µLOT) alone (159 eyes, 28%) or combined µLOT and cataract surgery (401 eyes, 72%) performed by one surgeon at Matsue Red Cross Hospital between May 2015 and March 2018 to control intraocular pressure (IOP) were retrospectively assessed. Preoperative and postoperative IOPs, numbers of antiglaucoma medications, the logarithm of the minimum angle of resolution visual acuity (logMAR VA), anterior chamber (AC) flare, visual field mean deviation (MD), and corneal endothelial cell density (CECD) were compared up to 36 months. Surgical complications and required interventions were described. The duration of the follow-up was 405 ± 327 (range, 2–1326) days. The mean preoperative IOP (20.2 ± 7.0 mmHg) and number of antiglaucoma medications (2.8 ± 1.1) decreased to 13.9 ± 4.5 mmHg (31% reduction, p < 0.0001) and 2.5 ± 1.0 (11% reduction, p < 0.0001), respectively, at the final visit. After combined surgery, compared with preoperatively, the final VA improved 0.11 logMAR (p < 0.0001), AC flare increased 4.5 photon counts/msec (p = 0.0011), MD improved 0.6 decibel (p < 0.0001), and the CECD decreased 6% (p < 0.0001). Layered hyphema (172 eyes, 31%) and hyphema washout (26 eyes, 5%) were the most common postoperative complication and intervention, respectively. At the final visit, 379 (69%) eyes achieved successful IOP control of ≤18 mmHg and ≥20% IOP reduction, and 349 (64%) eyes achieved successful IOP control of ≤15 mmHg and ≥20% IOP reduction. Older age, steroid-induced glaucoma, developmental glaucoma, and the absence of postoperative complications were associated with lower final IOP; exfoliation glaucoma, other types of glaucoma, and higher preoperative IOP were associated with higher final IOP. µLOT has a significant IOP-lowering potential in patients with glaucoma, and improves visual function when combined with cataract surgery.
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