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1.
J Mater Sci Mater Med ; 35(1): 37, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38916635

ABSTRACT

The current clinical application of glaucoma drainage devices is made of non-degradable materials. These non-degradable drainage devices often trigger inflammatory responses and scar proliferation, possibly leading to surgical failure. We developed a biodegradable material hydroxyapatite-coated magnesium (HA-Mg) as a glaucoma drainage device. Twelve New Zealand white rabbits were randomly assigned to three groups: HA-Mg drainage plate group (6 right eyes), trabeculectomy group (6 right eyes), and control group (12 left eyes). Results showed that all HA-Mg drainage plates were completely degraded ~4 months postoperatively. At the 5th month postoperatively, there was no statistical difference in the corneal endothelium density between the HA-Mg drainage plate group and the control group (p = 0.857). The intraocular pressure (IOP) level in the HA-Mg drainage plate implantation group was lower than in the other two groups. The trypan blue dye still drained from the anterior chamber to the subconjunctiva 5 months after HA-Mg drainage plate implantation. HE staining revealed the scleral linear aqueous humor drainage channel and anterior synechia were observed after drainage plate completely degraded, with no obvious infiltration with the inflammatory cells. This study showed the safety and efficacy of HA-Mg glaucoma drainage plate in controlling IOP after implantation into the anterior chamber of rabbit eyes.


Subject(s)
Anterior Chamber , Glaucoma Drainage Implants , Glaucoma , Intraocular Pressure , Magnesium , Animals , Rabbits , Anterior Chamber/surgery , Glaucoma/surgery , Magnesium/chemistry , Durapatite/chemistry , Trabeculectomy/methods
2.
Exp Eye Res ; 225: 109284, 2022 12.
Article in English | MEDLINE | ID: mdl-36273575

ABSTRACT

Inflammation-driven scarring is a major contributor to surgical failure after subconjunctival bleb forming glaucoma surgery. The current gold standard anti-scarring adjuvant mitomycin C (MMC) has variable effectiveness and is associated with significant risks. Acetylsalicylic acid (ASA), when delivered locally, repurposes the typically pro-inflammatory cyclooxygenase (COX-2) signaling for the resolution of inflammation and mitigating inflammation-mediated fibrosis. The aim of this study is to compare the effects of ASA and MMC in an in vitro model of subconjunctival scarring. Glaucoma patient-derived Tenon's capsule fibroblasts (HTCFs) were treated with TGFß1 (2 ng/mL) plus or minus ASA (1600 µg/ml), or MMC (0.05, 0.1, 0.2 mg/mL). In vitro collagen contraction, MTT, LDH, immunofluorescence, and Western blot assays were performed. To elucidate the mechanistic effects of ASA in TGFß1-induced HTCFs, liquid chromatography tandem mass spectrometry (LC-MS/MS) was used to identify and measure pro-inflammatory and pro-resolving lipid mediator secretion. ASA was at least as effective as MMC in reducing TGFß1-induced HTCF-mediated collagen contraction, metabolic activity, and pro-fibrotic protein expression, with less cytotoxicity. Within cytokine-activated HTCFs, ASA significantly impaired secretion of pro-inflammatory lipid mediators prostaglandin E2 and 6-keto-prostaglandin F1α and significantly increased secretion of the pro-resolving mediators 5-hydroxyeicosatetraenoic acid (HETE), 15-HETE and 18-hydroxyeicosapentaenoic acid (HEPE). ASA reduces cytokine-induced myofibroblast transdifferentiation in HTCFs, being non-inferior to MMC in vitro. ASA's effects are associated with a unique lipid mediator expression profile, suggesting that the ASA-induced resolution of inflammation may be a promising strategy to mitigate inflammation-mediated scarring and could offer a novel alternative as a surgical adjuvant.


Subject(s)
Glaucoma , Tenon Capsule , Humans , Tenon Capsule/metabolism , Mitomycin/pharmacology , Myofibroblasts/metabolism , Cell Transdifferentiation , Aspirin/pharmacology , Aspirin/metabolism , Cytokines/metabolism , Chromatography, Liquid , Tandem Mass Spectrometry , Fibroblasts/metabolism , Glaucoma/metabolism , Cicatrix/metabolism , Collagen/metabolism , Fibrosis , Inflammation/metabolism , Lipids , Cells, Cultured
3.
Ophthalmology ; 126(2): 223-232, 2019 02.
Article in English | MEDLINE | ID: mdl-30278197

ABSTRACT

PURPOSE: The effectiveness of selective laser trabeculoplasty (SLT) was compared with argon laser trabeculoplasty (ALT) in a randomized clinical trial for patients with medically uncontrolled open-angle glaucoma who have previously received 360° SLT. DESIGN: An active equivalence parallel armed randomized control trial. PARTICIPANTS: Patients with open-angle glaucoma including pigmentary dispersion syndrome and pseudoexfoliation syndrome were enrolled into the study from 7 different sites across Canada. METHODS: One setting of 180° of either SLT or ALT was assigned randomly and applied to each participant. MAIN OUTCOME MEASURES: The change in intraocular pressure (IOP) from baseline to 12 months was compared between the 2 groups. RESULTS: A total of 132 patients were recruited, 2 of which dropped out early in the study, leaving 130 patients who completed the study as per protocol. For those, the study's primary outcome was calculated. The IOP change at 1 year in comparison to baseline for SLT vs. ALT was found to be different by 0.33 mmHg between the 2 groups (3.16 for SLT and 2.83 for ALT) and was not statistically significant (P = 0.71) Further analysis, though, showed that SLT had a significantly lower IOP reduction at early time points: 1 week and 1 month, but this effect was lost by 3 months. Corresponding to this finding was the strong trend for ALT to fail more quickly than SLT. Although repeatable, the first repeat SLT reduced IOP to only about half compared with initial SLT treatment. CONCLUSIONS: The comparison at 12 months following the laser therapy showed that both modalities lowered the IOP with approximately 3 mmHg, yet essentially all of the time-to-failure analyses favored SLT over ALT. The repeat SLT effect was found to be half of the initial treatment.


Subject(s)
Exfoliation Syndrome/surgery , Glaucoma, Open-Angle/surgery , Laser Therapy/methods , Lasers, Gas/therapeutic use , Trabecular Meshwork/surgery , Trabeculectomy/methods , Aged , Equivalence Trials as Topic , Female , Glaucoma, Open-Angle/physiopathology , Humans , Intraocular Pressure/physiology , Male , Middle Aged , Single-Blind Method , Tonometry, Ocular , Treatment Outcome
4.
Exp Eye Res ; 182: 65-73, 2019 05.
Article in English | MEDLINE | ID: mdl-30910611

ABSTRACT

Dysregulated wound healing and subsequent fibrosis represents the most common cause of failure in glaucoma filtration surgery. Primary means to prevent this outcome are the anti-metabolite surgical adjuvants, however, topical corticosteroids are commonly used postoperatively to permit further control of wound healing and development of the filtration bleb. Unfortunately, they carry important side effects such as raised intraocular pressure, cataract and increased infection risk. Non-steroidal anti-inflammatory drugs (NSAIDs) show promising results in clinical trials as an alternative wound modulatory drug. NSAIDs exhibit non-inferiority to steroids in terms of post-operative intraocular pressure control and secondary IOP lowering interventions, however there is little known about the differing effects these drugs exert on human Tenon's capsule fibroblast (HTCF) mediated wound healing. The purpose of this study was to assess the individual effects of dexamethasone and indomethacin on the extracellular matrix modifying actions of HTCFs in vitro. To this end, HTCFs were cultured in 3D collagen matrices as well as in 2D monolayers and exposed to clinically relevant concentrations of dexamethasone or indomethacin for up to seven days. HTCF-mediated wound healing functions were assayed through collagen matrix contraction, extracellular matrix morphology, estimation of HCTF proliferation and differentiation into myofibroblasts within the collagen matrices, as well as western blot. Both drugs significantly reduced HTCF-mediated collagen contraction relative to control however there was a significant trend towards greater inhibition with indomethacin exposure compared to dexamethasone. Indomethacin exposure significantly reduced HTCF-mediated collagen remodelling activity compared vehicle control, whereas dexamethasone was unable to reduce remodelling activity at any of the studied exposures. Both drugs reduced myofibroblast differentiation, however indomethacin alone demonstrated an inhibitory effect on final cell number relative to control whereas dexamethasone had no significant effect at any studied exposure. These findings demonstrate that both steroidal and NSAID treatment can mitigate HTCF-mediated collagen contraction and αSMA expression. However, NSAIDs may function to better impede HTCF proliferation and remodelling activity. Taken in the context of previous glaucoma surgical trials, NSAIDs appear to be a viable alternative to steroids for post-operative wound modulation.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Dexamethasone/pharmacology , Fibroblasts/drug effects , Glaucoma/surgery , Indomethacin/pharmacology , Tenon Capsule/drug effects , Wound Healing/drug effects , Collagen/metabolism , Fibroblasts/metabolism , Humans , Tenon Capsule/metabolism
5.
Clin Exp Ophthalmol ; 47(6): 787-794, 2019 08.
Article in English | MEDLINE | ID: mdl-30816600

ABSTRACT

BACKGROUND: Primary open angle glaucoma (POAG) patients have hallmark increases in intraocular pressure (IOP) and noted dysfunction of the trabecular meshwork (TM). Connexin43 (Cx43) is a gap junction widely expressed on the TM that is important for intercellular communication. The human gene is known as gap junction alpha-1 (GJA1). Since the role of Cx43 in the TM is not fully understood, we set out to determine the effect of excess mechanical stretch on cultured human trabecular meshwork cells (hTMCs) and to specifically investigate the effect of stretch on Cx43 expression and function. METHODS: Primary hTMCs were cultured and subjected to 48 hours of 15% cyclic mechanical stretch at a frequency of 1 Hz. Levels of apoptosis and necrosis secondary to stretch were investigated using colorimetric assays. The effect of stretch on gap junction Cx43 and GJA1 was investigated by RT-PCR, immunoblotting and immunofluorescence. The migration of Lucifer Yellow dye was used to assess intercellular communication. RESULTS: Stretch significantly increased the rates of apoptosis and necrosis in hTMCs. The increased rate of injury in stretched hTMCs was further associated with significant upregulation of GJA1 mRNA and Cx43 protein. Upregulation of Cx43 protein was concomitant to increased intercellular communication. CONCLUSIONS: We have shown stretch to increase GJA1 gene and Cx43 protein expression, as well as intercellular communication. We have further shown stretch to be injurious to hTMCs. Upregulation of Cx43 in the hTM subsequent to stretch is a novel finding, which may be useful in elucidating the mechanism of TM injury in POAG patients.


Subject(s)
Connexin 43/genetics , Connexin 43/metabolism , Gene Expression Regulation/physiology , Stress, Mechanical , Trabecular Meshwork/metabolism , Adult , Apoptosis , Cell Communication/physiology , Cell Survival , Cells, Cultured , Fluorescent Antibody Technique, Indirect , Gap Junctions , Humans , Immunoblotting , Male , Necrosis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Trabecular Meshwork/pathology , Up-Regulation
6.
Clin Exp Ophthalmol ; 45(5): 520-528, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28013525

ABSTRACT

BACKGROUND: Microinvasive glaucoma surgery (MIGS) is a relatively new addition to the glaucoma treatment paradigm. Small metallic stents are inserted into the trabecular meshwork in order to increase aqueous humour drainage. MIGS procedures are rapidly being adopted owing to a more favourable side effect profile when compared with traditional surgery. Remarkably, this rapid rate of utilization has occurred without any published studies on the effect of metal alloys used in these stents on human trabecular meshwork cells (HTMCs). Therefore, this study aimed to determine the effect of candidate metal alloys for MIGS on HTMC morphology, viability and function. METHODS: Human trabecular meshwork cells were cultured on the surfaces of titanium (polished and sandblasted), a titanium-nickel (nitinol) alloy and glass (as control substratum). Fluorescence imaging was used to assess cell morphology and spreading. A lactate dehydrogenase cytotoxicity assay, cell death detection ELISA, MTT cell viability assay, BrdU cell proliferation assay and fibronectin ELISA were also conducted. RESULTS: Cells cultured on sandblasted titanium exhibited significantly greater spreading than cells cultured on other substrata. In comparison, HTMCs cultured on nitinol displayed poor spreading. Significantly more cell death, by both necrosis and apoptosis, occurred on nitinol than on titanium and glass. Also, cell viability and proliferation were suppressed on nitinol compared with titanium or glass. Finally, HTMCs on both titanium and nitinol produced greater amounts of fibronectin than cells grown on glass. CONCLUSIONS: Substratum topography and metal alloy composition were found to impact morphology, viability and function of primary HTMC cultures.


Subject(s)
Alloys/pharmacology , Filtering Surgery/methods , Glaucoma Drainage Implants , Glaucoma/pathology , Minimally Invasive Surgical Procedures , Trabecular Meshwork/ultrastructure , Apoptosis , Cell Proliferation , Cell Survival , Cells, Cultured , Colorimetry , Enzyme-Linked Immunosorbent Assay , Glaucoma/metabolism , Glaucoma/surgery , Humans , Microscopy, Electron, Scanning , Microscopy, Fluorescence , Trabecular Meshwork/drug effects , Trabecular Meshwork/metabolism
7.
Clin Exp Ophthalmol ; 44(1): 33-42, 2016.
Article in English | MEDLINE | ID: mdl-26241518

ABSTRACT

BACKGROUND: Matrix metalloproteinases (MMPs) are reported to contribute to the mechanism of argon laser trabeculoplasty, but it is unknown whether they are also secreted after selective laser trabeculoplasty (SLT). The aim of this study was to investigate whether human primary trabecular meshwork (HTM) cells secrete MMP-3 after stimulation by SLT. The relationship between SLT and the two principal forms of cell death, apoptosis and necrosis, was also examined. METHODS: Non-pigmented primary HTM cells were challenged with melanin granules to artificially introduce pigmentation. Isolated non-pigmented HTM cells and 1:1 co-cultures of pigmented and non-pigmented cells were treated with 0.5-1.5 mJ SLT. Cellular metabolic activity (CMA) was quantified using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Apoptosis and necrosis were measured using a cell death ELISA and a lactate dehydrogenase assay, respectively. MMP-3 secretion was measured by ELISA. RESULTS: Co-cultures exhibited a dose-dependent decline in CMA and a dose-dependent increase in necrosis 4 and 24 h after SLT. Non-pigmented cells did not undergo necrosis and displayed a trend towards increased CMA. Apoptosis was reduced in non-pigmented cells but elevated in co-cultures. Increased MMP-3 secretion was observed from co-cultures but not isolated non-pigmented cells. CONCLUSIONS: Pigmentation is necessary for both post-SLT cell death and MMP-3 secretion. SLT appears to have a hormetic effect on non-pigmented HTM cells.


Subject(s)
Laser Therapy , Matrix Metalloproteinase 3/metabolism , Trabecular Meshwork/enzymology , Trabecular Meshwork/surgery , Trabeculectomy , Apoptosis , Cells, Cultured , Coculture Techniques , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay , Humans , L-Lactate Dehydrogenase/metabolism , Lasers, Solid-State/therapeutic use , Melanins/pharmacology , Necrosis , Tetrazolium Salts , Thiazoles , Trabecular Meshwork/pathology
8.
Clin Exp Ophthalmol ; 43(2): 164-72, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25041649

ABSTRACT

BACKGROUND: Benzalkonium chloride (BAK) is a controversial ophthalmic preservative because of its prominent side-effect profile. In this study, we examined the mechanism of BAK toxicity in human trabecular meshwork cells (HTMC) and compared the effects of BAK with tafluprost free acid, which is an active form of tafluprost commercially available in a preservative-free formulation. METHODS: Primary HTMC were treated with different BAK concentrations over various exposure times. Cell viability was quantified using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenol tetrazolium bromide assay, and apoptosis was measured by enzyme-linked immunosorbent assay. The cell viability of primary HTMC exposed to various concentrations and times of tafluprost free acid was also determined. Cells were treated with BAK and tafluprost free acid for 30 min at 37°C, and cell viability was again assessed. The effect of BAK on the gap junction protein Connexin-43 (Cx43) expression was subsequently examined. RESULTS: BAK treatment resulted in a dose- and time-dependent decline in cell viability. Apoptosis increased following BAK treatment. Tafluprost-free acid treatment did not significantly affect cell viability. Tafluprost co-treatment with BAK resulted in an increase in cell viability as compared with BAK treatment alone. BAK treatment upregulated Cx43 expression in HTMC. CONCLUSIONS: These results demonstrate that BAK is harmful to the health of cultured HTMC. Tafluprost is both safe and cytoprotective against BAK for these HTMC. The effect of tafluprost on the gap junctions of the HTM should be further investigated.


Subject(s)
Apoptosis/drug effects , Benzalkonium Compounds/toxicity , Cytoprotection/drug effects , Preservatives, Pharmaceutical/toxicity , Prostaglandins F/pharmacology , Trabecular Meshwork/drug effects , Cell Survival/drug effects , Cells, Cultured , Connexin 43/metabolism , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay , Humans , Microscopy, Confocal , Tetrazolium Salts/metabolism , Thiazoles/metabolism , Time Factors , Trabecular Meshwork/metabolism , Trabecular Meshwork/pathology
9.
Clin Exp Ophthalmol ; 43(5): 443-8, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25495256

ABSTRACT

BACKGROUND: To assess the effects of amniotic membrane extract (AMX) on cellular activity of primary human corneal epithelial (HCE) cells under mechanical and oxidative stress, and on human limbal cells under oxidative stress. METHODS: Corneal mechanical stress was simulated with a linear scratch in confluent HCE cell plates, then incubated with 0.1% AMX for 48 and 72 h. Subjecting HCE cultures to 0.5 mmol/L tertiary-butylhydroperoxide for 1 h simulated an oxidative stress. 0.1% AMX-treated cultures were compared with controls at 24 and 48 h using cellular viability assay, along with 12-h AMX pretreatment and human limbal cell comparisons. RESULTS: Mechanical stress on HCE cultures revealed a statistically significant distance ratio at 48 and 72 h in favour of 0.1% AMX-treated cultures (P = 0.021 and 0.035, respectively). Oxidative stress did not reveal any significant difference in cellular viability of AMX-treated versus control cultures. Twelve hour AMX pre-treatment prior to oxidative stress revealed a significant difference after 24 h from oxidative injury (73.3% AMX vs. 66.0% control, P = 0.035), but not after 48 h. Human limbal cells demonstrated significantly improved oxidative viability compared with HCE cells, with (91.0% vs. 82.0% control, P = 0.017) and without 0.1% AMX pre-treatment (91.2% vs. 83.7% control, P = 0.019). CONCLUSIONS: HCE cells treated with AMX healed faster after mechanical insult, suggesting a potential benefit in acute corneal injuries. Under oxidative stress, human limbal cells, a more proliferative cell type, showed superior viability compared with HCE cells.


Subject(s)
Amnion/chemistry , Epithelium, Corneal/drug effects , Limbus Corneae/drug effects , Tissue Extracts/pharmacology , Cell Proliferation/drug effects , Cell Survival , Epithelium, Corneal/cytology , Humans , Limbus Corneae/cytology , Oxidative Stress , Stress, Mechanical , Wound Healing/physiology , tert-Butylhydroperoxide/toxicity
10.
J Biol Chem ; 288(25): 18146-61, 2013 Jun 21.
Article in English | MEDLINE | ID: mdl-23640897

ABSTRACT

Homeostasis is essential for cell survival. However, homeostatic regulation of surface epithelia is poorly understood. The eye surface, lacking the cornified barrier of skin, provides an excellent model. Tears cover the surface of the eye and are deficient in dry eye, the most common eye disease affecting at least 5% of the world's population. Only a tiny fraction of the tear proteome appears to be affected, including lacritin, an epithelium-selective mitogen that promotes basal tearing when topically applied to rabbit eyes. Here we show that homeostasis of cultured corneal epithelia is entirely lacritin-dependent and elucidate the mechanism as a rapid autophagic flux to promptly restore cellular metabolism and mitochondrial fusion in keeping with the short residence time of lacritin on the eye. Accelerated flux appears to be derived from lacritin-stimulated acetylation of FOXO3 as a novel ligand for ATG101 and coupling of stress-acetylated FOXO1 with ATG7 (which remains uncoupled without lacritin) and be sufficient to selectively divert huntingtin mutant Htt103Q aggregates largely without affecting non-aggregated Htt25Q. This is in keeping with stress as a prerequisite for lacritin-stimulated autophagy. Lacritin targets the cell surface proteoglycan syndecan-1 via its C-terminal amino acids Leu(108)-Leu(109)-Phe(112) and is also available in saliva, plasma, and lung lavage. Thus, lacritin may promote epithelial homeostasis widely.


Subject(s)
Autophagy/drug effects , Epithelial Cells/drug effects , Forkhead Transcription Factors/metabolism , Glycoproteins/pharmacology , Metabolome/drug effects , Amino Acid Sequence , Autophagy-Related Protein 7 , Autophagy-Related Proteins , Cells, Cultured , Epithelial Cells/metabolism , Forkhead Box Protein O3 , Forkhead Transcription Factors/genetics , Glycoproteins/chemistry , Glycoproteins/genetics , Homeostasis/drug effects , Humans , Huntingtin Protein , Interferon-gamma/pharmacology , Mass Spectrometry , Molecular Sequence Data , Mutation , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Peptides/pharmacology , RNA Interference , Recombinant Proteins/pharmacology , Syndecan-1/genetics , Syndecan-1/metabolism , Tears/chemistry , Tears/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Ubiquitin-Activating Enzymes/genetics , Ubiquitin-Activating Enzymes/metabolism , Vesicular Transport Proteins/genetics , Vesicular Transport Proteins/metabolism
11.
Clin Exp Ophthalmol ; 42(7): 675-81, 2014.
Article in English | MEDLINE | ID: mdl-24330092

ABSTRACT

Selective laser trabeculoplasty is a safe and effective treatment for glaucoma, with greater cost effectiveness than its pharmacological and surgical alternatives. Nevertheless, although the basic science literature on selective laser trabeculoplasty continues to grow, there remains uncertainty over the mechanism by which laser trabeculoplasty reduces intraocular pressure. To address this uncertainty, the evidence behind several potential biological and mechanical mechanisms of selective laser trabeculoplasty were reviewed. In particular, cytokine secretion, matrix metalloproteinase induction, increased cell division, repopulation of burn sites and macrophage recruitment were discussed. Refining our understanding of these mechanisms is essential both to understanding the pathophysiology of ocular hypertension and developing improved therapies to treat the condition.


Subject(s)
Argon Plasma Coagulation , Glaucoma/surgery , Trabecular Meshwork/surgery , Trabeculectomy/methods , Humans , Intraocular Pressure
12.
Can J Ophthalmol ; 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38901468

ABSTRACT

OBJECTIVE: Because of increased evidence for safety and increased demands, there appears to be a recent adoption and endorsement of immediate sequential bilateral cataract surgery (ISBCS). This study aims to determine whether a paradigm shift has occurred in the delivery of cataract surgery in the province of Ontario and its the extent, if any, and to analyze the current role of ISBCS. DESIGN: Retrospective health records analysis. METHODS: We analyzed aggregate Ontario Health Insurance Plan claim counts for cataract surgeries between 2016 and 2022, categorizing cases into unilateral, ISBCS, and delayed sequential bilateral cataract surgery (DSBCS) cases. We examined trends, compared wait times for second surgeries in the DSBCS cohort with wait times for first surgeries, and used previously published cost estimates for ISBCS to estimate annual savings in Ontario. RESULTS: There were 1,122 ISBCS cases in 2016, which increased sixfold during the pandemic (2020-2021) and further increased to 11,876 cases in 2022. Unilateral and DSBCS cases decreased during the pandemic but rebounded in 2022 to 102% and 153% of baseline, respectively. ISBCS increased from 1% to 10%, unilateral cases decreased from 41% to 29% of total cases, and DSBCS increased from 58% to 61%. Median wait for patients' first and second surgeries increased from 65 to 87 days and 28 to 33 days, respectively. Using estimates, ISBCS saved approximately $19 million in 2022. CONCLUSION: Our study demonstrates a paradigm shift in Ontario in favour of ISBCS. ISBCS also may be a strategy to reduce increasing wait times while saving health care system dollars.

13.
Eye (Lond) ; 38(8): 1518-1528, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38326483

ABSTRACT

BACKGROUND: To investigate the effect of perioperative intraocular pressure (IOP) lowering medications on controlling postoperative IOP following uncomplicated phacoemulsification. METHODS: Ovid MEDLINE, EMBASE, and Cochrane CENTRAL databases were searched up until November 2022. Randomised controlled trials (RCTs) that assessed IOP change via applanation tonometry in medicated and control arms following uncomplicated cataract surgery in healthy eyes were included. The primary outcome was the weighted mean difference (WMD) of IOP at 2-8 h, 12-24 h, and 1-7 days postoperatively within each medication class or common fixed-combination formulations. Risk of bias was assessed using the revised risk of bias in randomised trials (RoB-2). Level of evidence was rated using the Grading of Recommendation, Assessment, Development and Evaluation (GRADE) RESULTS: From 702 screened articles, 30 RCTs involving 2986 eyes were included. There was a statistically significant reduction in IOP favouring treatment arms at 2-8 h (WMD = -3.87 mmHg; 95% CI [-4.75, -3.00]; p < 0.001) and 12-24 h (WMD = -2.69 mmHg; 95% CI [-3.36, -2.02]; p < 0.001), with the effect wearing off beyond 1 day (p = 0.18). Between medication classes, the largest effect at both 2-8 h and 12-24 h was observed with intracameral cholinergics or fixed-combination carbonic anhydrase inhibitor-beta-blocker (FCCB) formulations. Conversely, the smallest effect was observed with prostaglandin analogues, alpha-agonists, and topical carbonic anhydrase inhibitors (CAIs). CONCLUSION: Prophylaxis against acute IOP elevations following uncomplicated cataract surgery is effective. FCCB and intracameral cholinergics are the most effective ocular antihypertensive agents, while alpha-agonists, prostaglandin analogues, and topical CAIs were found to be the least effective. These findings may inform future surgical guidelines.


Subject(s)
Antihypertensive Agents , Intraocular Pressure , Phacoemulsification , Humans , Intraocular Pressure/drug effects , Intraocular Pressure/physiology , Antihypertensive Agents/therapeutic use , Postoperative Complications/prevention & control , Tonometry, Ocular , Ocular Hypertension/prevention & control
14.
Bioengineering (Basel) ; 11(2)2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38391628

ABSTRACT

Distal outflow bleb-forming procedures in ophthalmic surgery expose subconjunctival tissue to inflammatory cytokines present in the aqueous humor, resulting in impaired outflow and, consequently, increased intraocular pressure. Clinically, this manifests as an increased risk of surgical failure often necessitating revision. This study (1) introduces a novel high-throughput screening platform for testing potential anti-fibrotic compounds and (2) assesses the clinical viability of modulating the transforming growth factor beta-SMAD2/3 pathway as a key contributor to post-operative outflow reduction, using the signal transduction inhibitor verteporfin. Human Tenon's capsule fibroblasts (HTCFs) were cultured within a 3D collagen matrix in a microfluidic system modelling aqueous humor drainage. The perfusate was augmented with transforming growth factor beta 1 (TGFß1), and afferent pressure to the tissue-mimetic was continuously monitored to detect treatment-related pressure elevations. Co-treatment with verteporfin was employed to evaluate its capacity to counteract TGFß1 induced pressure changes. Immunofluorescent studies were conducted on the tissue-mimetic to corroborate the pressure data with cellular changes. Introduction of TGFß1 induced treatment-related afferent pressure increase in the tissue-mimetic. HTCFs treated with TGFß1 displayed visibly enlarged cytoskeletons and stress fiber formation, consistent with myofibroblast transformation. Importantly, verteporfin effectively mitigated these changes, reducing both afferent pressure increases and cytoskeletal alterations. In summary, this study models the pathological filtration bleb response to TGFß1, while demonstrating verteporfin's effectiveness in ameliorating both functional and cellular changes caused by TGFß1. These demonstrate modulation of the aforementioned pathway as a potential avenue for addressing post-operative changes and reductions in filtration bleb outflow capacity. Furthermore, the establishment of a high-throughput screening platform offers a valuable pre-animal testing tool for investigating potential compounds to facilitate surgical wound healing.

15.
Can J Ophthalmol ; 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38431270

ABSTRACT

OBJECTIVE: This study aimed to assess whether the research output of medical students who matched into a Canadian ophthalmology residency program influences their subsequent research productivity during residency, decision to pursue a fellowship, or engagement in academic practice. DESIGN: Retrospective database review. PARTICIPANTS: A total of 369 trainees commencing ophthalmology residency from 2004 to 2015 at 15 residency programs. METHODS: Each trainee's publication record was queried in Scopus before and after the date they started residency. Multiple public sources were searched to identify fellowship placement and the type of subsequent practice (i.e., academic or community). Predictors of research productivity during residency, fellowship, and practice setting were assessed using multivariable regression analyses. RESULTS: Trainees with pre-residency publications (n = 187) demonstrated significantly higher research productivity during residency than those without pre-residency publications (n = 182), with a mean of 5.17 ± 5.97 versus 1.60 ± 2.38 publications on any topic (p < 0.001). Pre-residency research output was a predictor of research productivity during residency (relative risk = 1.17; 95% CI, 1.09-1.27; p < 0.001), pursuing fellowship (odds ratio, 2.9; 95% CI, 1.74-4.83), and an academic career (odds ratio = 1.85; 95% CI, 1.07-3.2). CONCLUSION: Pre-residency research output is a significant predictor of research productivity during residency and subsequent career choices, suggesting that pre-residency publishing reflects a propensity toward an academic trajectory. Residency publication count moderates this association, underscoring the role of the residency program environment in fostering research productivity. Addressing barriers such as mentorship, funding, and curriculum may be key to incentivizing trainees to pursue academic medicine.

16.
Can J Ophthalmol ; 58(4): 346-355, 2023 08.
Article in English | MEDLINE | ID: mdl-35305959

ABSTRACT

OBJECTIVE: This study aims to synthesize data quantifying the prevalence and severity of common psychological conditions in patients with glaucoma. DESIGN: Systematic review and meta-analysis. METHODS: Databases including Ovid MEDLINE, CINAHL, EMBASE, PsycINFO, Cochrane Library, Web of Science, Open Grey, and ProQuest Theses and dissertations were searched. Two reviewers independently assessed and screened all studies, followed by quality assessment of included studies using the modified Downs and Black checklist. Data were pooled using fixed-effect and random-effects models. RESULTS: Of 2067 studies identified by the search strategy, 57 passed full-text screening, and 45 studies (4 995 538 subjects) were eligible for analysis. Overall, the prevalence of depression (effect size [ES] = 0.19, 95% CI 0.16-0.23; n = 31), anxiety (ES = 0.25, 95% CI 0.21-0.30; n = 18), and sleep disorders (ES = 0.47, 95% CI 0.26-0.68; n = 7) were high in patients with glaucoma. Similarly, symptomatic measurements of depression (standardized mean difference [SMD] = 0.46, 95% CI 0.19-0.73), anxiety (SMD = 0.44, 95% CI 0.08-0.81), and sleep quality (SMD = 0.72, 95% CI 0.22-1.21) were significant in glaucoma patients. CONCLUSIONS: A higher prevalence and severity of depression, anxiety, and sleep disorders was experienced in patients with glaucoma compared with patients without glaucoma. Caregivers as well as health care providers may need to be aware of unique psychological and social stressors placed on glaucoma patients.


Subject(s)
Depression , Sleep Wake Disorders , Humans , Depression/diagnosis , Depression/epidemiology , Depression/etiology , Quality of Life , Anxiety/epidemiology , Sleep
17.
Transl Vis Sci Technol ; 12(2): 31, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36826843

ABSTRACT

Purpose: The gold standard for managing postoperative ocular fibrosis in glaucoma surgery is the chemotherapeutic mitomycin C (MMC) despite its association with significant adverse effects. This study compares in vitro the antifibrotic efficacy and cytotoxicity of the small-molecule TGFß1 inhibitor SB-431542 (SB) to MMC. Methods: To measure collagen contraction, human Tenon's capsule fibroblasts (HTCFs) embedded in a three-dimensional collagen lattice were exposed to 0.2 mg/mL MMC or 20 µM SB followed by incubation with 2 ng/mL TGFß1. Total protein extracted from experimentally treated HTCFs underwent immunoblotting for α-smooth muscle actin (α-SMA), matrix metallopeptidase 9 (MMP-9), and EDA splice-variant fibronectin (EDA-FN) expression. Cytotoxicity and cell metabolism were assessed using LIVE/DEAD staining, lactate dehydrogenase (LDH) assay, and methylthiazole tetrazolium (MTT) assay. Results: Collagen lattice contraction in TGFß1-induced HTCFs was significantly lowered by SB and MMC. Pretreatment with SB and MMC significantly lowered protein expression of α-SMA, MMP-9, and EDA-FN in HTCFs relative to TGFß1 alone. HTCF viability in collagen lattices was significantly reduced with MMC pretreatment but not SB pretreatment. MMC-pretreated HTCFs had a significant increase in LDH release after 3 hours and a decrease in MTT activity after 20 minutes, while SB-pretreated HTCFs showed no significant changes via MTT or LDH assay during the same treatment period. Conclusions: SB shows comparable efficacy to MMC in reducing expression of fibrosis-promoting proteins in HTCFs and in vitro scarring activity. SB distinguishes itself from MMC by exhibiting less cytotoxicity in both two-dimensional and three-dimensional in vitro assays. Translational Relevance: This study demonstrates in vitro the potential of SB as a safer alternative ocular antifibrotic agent.


Subject(s)
Glaucoma , Mitomycin , Humans , Mitomycin/metabolism , Mitomycin/pharmacology , Tenon Capsule/metabolism , Tenon Capsule/pathology , Cicatrix/metabolism , Matrix Metalloproteinase 9/metabolism , Matrix Metalloproteinase 9/pharmacology , Fibroblasts/metabolism , Fibroblasts/pathology , Collagen , Glaucoma/surgery
18.
Ophthalmol Glaucoma ; 6(5): 541-563, 2023.
Article in English | MEDLINE | ID: mdl-37142217

ABSTRACT

TOPIC: The purpose of the current study was to systematically identify and evaluate existing patient-reported outcome measures (PROMs) for clinical glaucoma practice. CLINICAL RELEVANCE: Understanding and incorporating patient preferences into decision-making is now recognized as critical for optimal resource allocation, especially in technologically advancing areas, such as minimally invasive surgeries. Patient-reported outcome measures are instruments designed to evaluate the health outcomes that are most important to patients. Despite their recognized importance, especially in the era of patient-centered care, their routine use in clinical settings remains low. METHODS: A systematic literature search was conducted in 6 databases (EMBASE, MEDLINE, PsycINFO, Scopus, BIOSIS, and Web of Science) from the date of inception. Studies were included in the qualitative review if they reported measurement properties of PROMs in adult patients with glaucoma. COnsensus-based Standards for the selection of health Measurement INstruments guidelines were used to assess the included PROMs. The study protocol is registered with PROSPERO (registration number: CRD42020176064). RESULTS: The literature search yielded 2661 records. After deduplication, 1259 studies entered level 1 screening, and based on title and abstract review, 164 records proceeded to full-text screening. In 48 included studies, 70 instrument reports discuss 43 distinct instruments in 3 major categories: glaucoma-specific, vision-specific, and general health-related quality of life. Most used measures were glaucoma-specific (Glaucoma Quality of Life [GQL] and Glaucoma Symptom Scale [GSS]) and vision-specific (National Eye Institute Visual Function Questionnaire [NEI VFQ-25]). All 3 have sufficient validity (especially construct), with GQL and GSS having sufficient internal consistency, cross-cultural validity, and reliability, with reports suggesting high methodological quality. CONCLUSION: The GQL, GSS, and NEI VFQ-25 are the 3 most used questionnaires in a research setting, having considerable validation in a patient population with glaucoma. Limited reports on interpretability, responsiveness, and feasibility in all 43 identified instruments make identifying a single optimal questionnaire for clinical use challenging and highlight the need for further studies. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Subject(s)
Glaucoma , Quality of Life , Adult , Humans , Reproducibility of Results , Patient Reported Outcome Measures , Glaucoma/diagnosis , Surveys and Questionnaires
19.
Womens Health (Lond) ; 19: 17455057231219613, 2023.
Article in English | MEDLINE | ID: mdl-38130083

ABSTRACT

BACKGROUND: Although women remain historically underrepresented in medical achievement awards, gender distribution of award recipients in ophthalmology in Canada remain to be explored based on research productivity metrics. OBJECTIVE: To characterize the gender distribution of award recipients among the main Canadian national ophthalmological societies and subspecialty affiliates based on research productivity, graduate degrees, affiliated institution, and award type. DESIGN: Retrospective, observational study. METHODS: Award recipients were selected from the Canadian Ophthalmological Society (COS), Canadian Association of Paediatric Ophthalmology and Strabismus (CAPOS); Canadian Cornea, External Disease, and Refractive Surgery Society (CCEDRSS); Canadian Council of Ophthalmology Residents (CCOR) Research Proposal Award; and Canadian Glaucoma Society (CGS). The recipients' gender was determined by web search for the gender-specific pronoun, profile photograph check, or using Gender-API. Outcomes included gender distribution of recipients per award, society, year, and training level and differences in research productivity. RESULTS: Thirteen special awards were given to 255 recipients (215 individuals) from 1995 to 2022. In total, 31% of recipients were women, the majority being from Canada. Women had a significantly lower median h-index (2.0 (0-62) women versus 4.0 (0-81) men, p = 0.001) and number of published documents (3.0 (0-213) women versus 8.0 (0-447) men, p < 0.001). On stratified analyses by type of award (research or lifetime achievement) and level of training (trainee or ophthalmologist), significant differences were found for mean h-index and number of publications for awardees within the research category (p = 0.01 and p = 0.02, respectively) and trainee level (p = 0.01 and p = 0.02, respectively). Overall, women's proportion rates in awards did not reach parity in 27 out of the 28 years analyzed. CONCLUSION: Women were confirmed to be historically minored in proportion among the prominent society awards in Canada, with attested research disparity possibly explaining some of this bias. These findings require further confirmation in larger cohorts accounting for additional educational, institutional, and provincial factors. REGISTRATION: Not applicable.


Subject(s)
Awards and Prizes , Ophthalmology , Female , Humans , Male , Canada , Retrospective Studies , Societies, Medical
20.
Ocul Immunol Inflamm ; 31(1): 65-76, 2023 Jan.
Article in English | MEDLINE | ID: mdl-34648419

ABSTRACT

PURPOSE: Inflammation is associated with, and may be causal of, a variety of ophthalmic pathologies. These pathologies are currently difficult to model in vitro because they involve complex interactions between the innate immune system, stromal cells, and other cells that normally maintain ocular tissue homeostasis. Using transscleral drainage channel fibrosis after glaucoma surgery as an example of inflammation-associated ocular fibrosis, we have assessed a simple but novel 3D cell culture system designed to reveal the immunomodulatory impacts of ocular connective tissue cells on monocytes, a major cellular component of the circulating immune system. METHODS: Primary human Tenon's capsule fibroblasts derived from five unrelated patients were activated into myofibroblasts in 3D collagen matrices under isometric tension, with and without exposure to an inflammatory cytokine-enhanced milieu, and co-cultured with an immortalized human monocyte cell line (THP-1 cells). Quantitative PCR analyses were performed on 8 candidate genes to assess the impacts of inflammatory cytokines on the myofibroblasts and the monocytes in mono-cultures and compared to cells in co-culture to clearly distinguish any co-culture-induced impacts on gene expression. RESULTS: Our data indicate that both Tenon's capsule myofibroblasts in 3D mono-culture and THP-1 monocytes in suspension mono-culture were responsive to inflammatory cytokine stimuli. Co-culture with Tenon's capsule myofibroblasts significantly modulated the gene expression responses of THP-1 monocytes to inflammatory cytokine stimulation, indicative of an immunomodulatory "feedback" system between these cell types. CONCLUSION: Our findings provide proof of principle for the use of simple 3D co-culture systems as a means to enhance our understanding of ocular stromal cell interactions with cells of the innate immune system and to provide more informative in vitro models of inflammation-associated ophthalmic pathologies.


Subject(s)
Glaucoma , Myofibroblasts , Humans , Coculture Techniques , Monocytes/metabolism , Glaucoma/surgery , Fibrosis , Cytokines/metabolism , Inflammation/metabolism , Cells, Cultured
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