Trabecular meshwork

INTRODUCTION: We report a case of bilateral pigment dispersion syndrome after 13 years of uncomplicated implantable collamer lens (ICL) surgery. CASE PRESENTATION: A 53-year-old woman was referred from her optometrist to our glaucoma clinic due to early superonasal visual field loss in both eyes. She was asymptomatic with no changes in visual acuity and had undergone bilateral ICL implantation 13 years ago to correct her high myopia. Clinical examination revealed pigment deposition on the corneal endothelium, iris transillumination defects, and iris vaulting at the areas of contact with the ICL...

PURPOSE: Genome-wide association studies have recently uncovered many loci associated with variation in intraocular pressure (IOP). Artificial intelligence (AI) can be used to interrogate the effect of specific genetic knockouts on the morphology of trabecular meshwork cells (TMCs) and thus, IOP regulation. DESIGN: Experimental study. SUBJECTS: Primary TMCs collected from human donors. METHODS: Sixty-two genes at 55 loci associated with IOP variation were knocked out in primary TMC lines...

Atomic force microscopy (AFM) is a valuable tool for assessing mechanical properties of biological samples, but interpretations of measurements on whole tissues can be difficult due to the tissue's highly heterogeneous nature. To overcome such difficulties and obtain more robust estimates of tissue mechanical properties, we describe an AFM force mapping and data analysis pipeline to characterize the mechanical properties of cryosectioned soft tissues. We assessed this approach on mouse optic nerve head and rat trabecular meshwork, cornea, and sclera...

Aqueous humor (AQH) is a transparent fluid with characteristics similar to those of the interstitial fluid, which fills the eyeball posterior and anterior chambers and circulates in them from the sites of production to those of drainage. The AQH volume and pressure homeostasis is essential for the trophism of the ocular avascular tissues and their normal structure and function. Different AQH outflow pathways exist, including a main pathway, quite well defined anatomically and referred to as the conventional pathway, and some accessory pathways, more recently described and still not fully morphofunctionally understood, generically referred to as unconventional pathways...

BACKGROUND: Various cell culture platforms that could display native environmental cue-mimicking stimuli were developed, and effects of environmental cues on cell behaviors were studied with the cell culture platforms. Likewise, various cell culture platforms mimicking native trabecular meshwork (TM) composed of juxtacanalicular, corneoscleral and uveal meshwork located in internal scleral sulcus were used to study effects of environmental cues and/or drug treatments on TM cells and glaucoma development...

This study presents a 3D in vitro cell culture model, meticulously 3D printed to replicate the conventional aqueous outflow pathway anatomical structure, facilitating the study of trabecular meshwork (TM) cellular responses under glaucomatous conditions. Glaucoma affects TM cell functionality, leading to extracellular matrix (ECM) stiffening, enhanced cell-ECM adhesion, and obstructed aqueous humor outflow. Our model, reconstructed from polyacrylamide gel with elastic moduli of 1.5 and 21.7 kPa, is based on serial block-face scanning electron microscopy images of the outflow pathway...

Aim: To assess the incidence, risk factors, and treatment outcomes in intravitreal triamcinolone acetonide injection (IVTA) induced intraocular pressure rise and to compare IOP rise in 1-mg and 2-mg IVTA. Materials and methods: Prospective observational study conducted in all eyes receiving IVTA. Any pre-existing glaucoma and patients who received IVTA or dexamethasone implant in the last 6 months were excluded. Results: 9 between 61-70 years of age developed an IOP spike. The mean and standard deviation of age in years was 61...

OBJECTIVES: Glaucoma is a multifactorial optic neuropathy with a high rate of irreversible visual loss, and its pathogenesis is complex and still unclear. Elevated intraocular pressure (IOP) is well recognized as the sole modifiable risk factor for the development of glaucoma in the majority of cases. This study aims to compare 2 different methods of inducing chronic ocular hypertension by circumlimbal suture or by laser burns in degree and lasting time of the IOP, different status of the retina and retinal ganglion cells (RGCs), and changes of the microstructure of neurons...

PURPOSE: To compare the microstructure of the corneal endothelial transition zone in different laboratory animals. METHODS: Flat-mount corneas of rabbits, rats, and mice were stained with Alizarin Red S (ARS) and observed using scanning electron microscopy (SEM). The progenitor cell markers p75 neurotrophin receptor (p75NTR), SRY-box transcription factor 9 (SOX9), leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5), telomerase reverse transcriptase (TERT), and proliferation marker Ki -67 were examined in the flat-mounted corneas of three laboratory animals using immunofluorescence microscopy...

BACKGROUND: Primary Angle Closure Glaucoma (PACG), is caused by narrowing the iridocorneal angle and increases the risk of blockage in the trabecular meshwork. Phacoemulsification and laser peripheral iridotomy (LPI) effectively control IOP elevation and widen the angle. This systematic review and meta-analysis compared Phacoemulsification and LPI Effectiveness for PACG. METHODS: We searched Medline, Embase, and CENTRAL. We included randomized controlled trials (RCTs) that compared Phacoemulsification and LPI for individuals with PACG...

Timolol maleate (TML) is a beta-blocker drug that is commonly used to lower the intraocular pressure in glaucoma. This study focused on using a 3D printing (3DP) method for the manufacturing of an ocular, implantable, sustained-release drug delivery system (DDS). Polycaprolactone (PCL), and PCL with 5 or 10% TML implants were manufactured using a one-step 3DP process. Their physicochemical characteristics were analysed using light microscopy, scanning electronic microscopy (SEM), differential scanning calorimetry (DSC) / thermal gravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR)...

BACKGROUND AND OBJECTIVES: Femtosecond laser trabeculotomy (FLT) creates aqueous humor outflow channels through the trabecular meshwork (TM) and is an emerging noninvasive treatment for open-angle glaucoma. The purpose of this study is to investigate the effect of pulse energy on outflow channel creation during FLT. MATERIALS AND METHODS: An FLT laser (ViaLase Inc.) was used to create outflow channels through the TM (500 μm wide by 200 μm high) in human cadaver eyes using pulse energies of 10, 15, and 20 μJ...

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...

Age and elevated intraocular pressure (IOP) are the two primary risk factors for glaucoma, an optic neuropathy that is the leading cause of irreversible blindness. In most people, IOP is tightly regulated over a lifetime by the conventional outflow tissues. However, the mechanistic contributions of age to conventional outflow dysregulation, elevated IOP and glaucoma are unknown. To address this gap in knowledge, we studied how age affects the morphology, biomechanical properties and function of conventional outflow tissues in C57BL/6 mice, which have an outflow system similar to humans...

Glaucoma is a blinding disease. Reduction of intraocular pressure (IOP) is the mainstay of treatment, but current drugs show side-effects or become progressively ineffective, highlighting the need for novel compounds. We have synthesized a family of perhydro-1,4-oxazepine derivatives of digoxin, the selective inhibitor of Na,K-ATPase. The cyclobutyl derivative (DcB) displays strong selectivity for the human a2 isoform and potently reduces IOP in rabbits. These observations appeared consistent with a hypothesis that in ciliary epithelium DcB inhibits the a2 isoform of Na,K-ATPase, which is expressed strongly in non-pigmented cells, reducing aqueous humor (AH) inflow...

PURPOSE: To investigate the potential effects and mechanism of nicotinamide riboside (NR) on the oxidative stress and fibrosis model of human trabecular meshwork (HTM) cell line cells. METHODS: HTM cells were pretreated with NR, followed by the induction of oxidative injury and fibrosis by hydrogen peroxide (H2O2) and TGF-β2, respectively. Cell viability was tested using Hoechst staining and MTT assays, cell proliferation was assessed by EdU assay, and cell apoptosis was detected by flow cytometry and western blotting...

Human T-cell leukemia virus type 1 (HTLV-1), a virus that affects 5-10 million people globally, causes several diseases, including adult T-cell leukemia-lymphoma and HTLV-1-associated uveitis (HU). HU is prevalent in Japan and often leads to secondary glaucoma, which is a serious complication. We investigated the efficacy of ripasudil, a Rho-associated coiled coil-forming protein kinase inhibitor, in alleviating changes in human trabecular meshwork cells (hTM cells) infected with HTLV-1. HTLV-1-infected hTM cells were modeled in vitro using MT-2 cells, followed by treatment with varying concentrations of ripasudil...

OBJECTIVE: The morphology and functions of the human trabecular meshwork (HTM) are dysregulated in glaucoma, and the molecular mechanisms of this dysregulation remain unknown. According to an established in vitro model, whose function was to study the regulatory networks sustaining the response of HTM cells to the increased substrate stiffness, we systematically analyzed the expression pattern of long noncoding RNAs (lncRNAs), the important regulatory RNAs in cells. METHODS: Bioinformatics analysis was performed to identify the dysregulated lncRNAs in response to increased substrate stiffness using transcriptome sequencing data (RNA-seq)...

PURPOSE: To compare aqueous humor outflow (AHO) pathway patterns between eyes of childhood glaucoma patients and non-glaucomatous patients receiving cataract surgery. METHODS: Aqueous angiography was performed in childhood glaucoma eyes (n = 5) receiving glaucoma surgery and in pediatric (n = 1) and healthy adult (n = 5) eyes receiving cataract surgery. Indocyanine green (0.4%) was introduced into the anterior chamber, and AHO was imaged using an angiographic camera (SPECTRALIS HRA+OCT with Flex Module)...

Background : To assess the anterior scleral thickness (AST), Schlemm's canal diameter (SCD), trabecular meshwork diameter (TMD) and conjunctiva tenon capsule thickness (CTT) in high myopic (HM) subjects and HM subjects with glaucoma (HMG) compared to control eyes. Methods: One hundred and twenty eyes were included, and AST at 0, 1, 2 and 3 mm from the scleral spur, SCD, TMD and CTT were measured. Results : Mean age was 64.2 ± 11.0 years, and the temporal SCD and temporal TMD were significantly longer in the HMG subjects compared to the controls (380...