Glaucoma is the leading cause of irreversible blindness worldwide, with its primary risk factor arising from elevated intraocular pressure (IOP) due to an imbalance between aqueous humor production and outflow. This study aims to establish quantitative correlations among IOP, iris mechanical properties, channel microstructures, and aqueous humor dynamics through three-dimensional modeling and finite element analysis, overcoming the limitations of conventional experimental techniques in studying aqueous flow within the trabecular meshwork (TM) outflow pathway. A three-dimensional fluid-structure interaction (FSI) model incorporating the layered TM structure, Schlemm's canal (SC), iris, and other anterior segment tissues was developed based on human ocular anatomy. FSI simulations were performed to quantify the effects of IOP variations and iris Young's modulus on tissue morphology and aqueous humor dynamics parameters. The computational results demonstrated that axial iris deformation showed significant correlations with IOP and iris Young's modulus. Although elevated IOP exhibited minimal effects on hydrodynamic parameters in the anterior and posterior chambers, it markedly suppressed aqueous flow velocity in the TM region. Additionally, wall shear stress in SC and collector channels displayed high sensitivity to IOP variations. These findings reveal that the tissue mechanics-FSI mechanism modulates outflow resistance by regulating aqueous humor dynamics, offering valuable references for developing clinical therapies targeting IOP reduction in glaucoma management.
Humans ; Trabecular Meshwork/anatomy & histology* ; Finite Element Analysis ; Aqueous Humor/metabolism* ; Intraocular Pressure/physiology* ; Glaucoma/physiopathology* ; Iris/anatomy & histology* ; Computer Simulation ; Models, Biological

OBJECTIVES: To compare the efficacy of toric implantable collamer lens (Toric-ICL) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) for myopia correction in patients with moderate to high myopia complicated with astigmatism. METHODS: We retrospectively collected data from 64 patients (aged 18-42 years) with moderate to high myopia complicated with astigmatism (128 eyes) undergoing either Toric-ICL (28 patients/56 eyes) or FS-LASIK (36 patients/72 eyes) at our department between January, 2019 and December, 2020. The changes of uncorrected distance visual acuity (UCVA), spherical equivalent (SE), mean astigmatism correction index (CI), corneal endothelial cell density (ECD) and intraocular pressure (IOP) following the procedures were compared between the two groups. RESULTS: In FS-LASIK group, all the eyes (72/72) achieved an UCVA≥1.0, similar to the rate in Toric-ICL group (55/56 eyes; P=0.2374). The postoperative SE was also comparable between FS-LASIK and Toric-ICL groups [0.43±0.06 D (range: -1.0 to 1.50 D) vs 0.38±0.05 D (range: -0.75 to 1.00 D); P=0.56]. The mean astigmatism CI was significantly higher in FS-LASIK group than in Toric-ICL group (0.8561 vs 0.7176; P<0.0001), and 88.89% of the eyes in FS-LASIK group and 69.64% in Toric-ICL group had postoperative astigmatism ≤0.50 D. No significant changes were observed in postoperative corneal ECD in FS-LASIK group, whereas ECD decreased significantly after the procedure in Toric-ICL group (P=0.0057). The patients undergoing Toric-ICL exhibited no significant changes of postoperative IOP, but the patients receiving FS-LASIK had significantly reduced IOP after the procedure (P<0.001). CONCLUSIONS Although the patients included in Toric-ICL group had higher myopia and astigmatism, Toric-ICL still showed better predictability and efficacy for astigmatic correction in Toric-ICL group. Toric-ICL is an effective and safe equivalent of FS-LASIK for correcting moderate myopia but can be more advantageous for correcting high myopia with astigmatism.
Humans ; Astigmatism/complications* ; Myopia/complications* ; Keratomileusis, Laser In Situ/methods* ; Retrospective Studies ; Adult ; Visual Acuity ; Adolescent ; Young Adult ; Treatment Outcome ; Male ; Lens Implantation, Intraocular/methods* ; Female ; Phakic Intraocular Lenses ; Intraocular Pressure

Neuronal injury in glaucoma persists despite effective intraocular pressure (IOP) control, necessitating neuroprotective strategies for retinal ganglion cells (RGCs). In this study, we investigated the neuroprotective role of the γ-hydroxybutyrate analog HOCPCA in a glaucoma model, focusing on its effects on CaMKII signaling, oxidative stress, and neuroinflammatory responses. Retinal tissue from high IOP animal models was analyzed via proteomics. In vitro mouse retinal explants were subjected to elevated pressure and oxidative stress, followed by HOCPCA treatment. HOCPCA significantly mitigated the RGC loss induced by oxidative stress and elevated pressure, preserving neuronal function. It restored CaMKIIα and β levels, preserving RGC integrity, while also modulating oxidative stress and neuroinflammatory responses. These findings suggest that HOCPCA, through its interaction with CaMKII, holds promise as a neuroprotective therapy for glaucoma.
Animals ; Retinal Ganglion Cells/metabolism* ; Glaucoma/pathology* ; Oxidative Stress/drug effects* ; Neuroprotective Agents/pharmacology* ; Mice ; Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism* ; Mice, Inbred C57BL ; Disease Models, Animal ; Neuroinflammatory Diseases/drug therapy* ; Neuroprotection/drug effects* ; Male ; Intraocular Pressure/drug effects*

Animals ; Macaca mulatta ; Optic Disk ; Glaucoma ; Craniocerebral Trauma ; Intraocular Pressure ; Low Tension Glaucoma

OBJECTIVE: To investigate the clinical efficacy of dexamethasone vitreous cavity implants (Ozurdex) for the treatment of macular edema (Irvine-Gass Syndrome) after cataract surgery. METHOD: Eight patients (eight eyes) with Irvine-Gass syndrome were enrolled for vitreous injections with Ozurdex. The patients included six men (six eyes) and two women (two eyes) with a mean age of 67.12 ± 11.92 years. Changes in the patients best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure were compared before and after treatment. RESULT: The mean visual acuity BCVA of the patients was 0.81 ± 0.26 before implantation, which improved to 0.20 ± 0.12, 0.13 ± 0.09, and 0.15 ± 0.13 at 2 weeks, 1 month, and 3 months after implantation, respectively ( P < 0.001). The patient's mean CMT before implantation was 703.00 ± 148.88 μm, and it reduced to 258.87 ± 37.40 μm, 236.25 ± 28.74 μm, and 278.00 ± 76.82 μm at 2 weeks, 1 month, and 3 months after implantation, respectively ( P < 0.001). CONCLUSION The dexamethasone vitreous cavity implant (Ozurdex) is a safe and effective treatment, which can effectively improve patient's visual acuity and reduce macular edema associated with cataract surgery.
Male ; Humans ; Female ; Middle Aged ; Aged ; Macular Edema/etiology* ; Dexamethasone/therapeutic use* ; Intraocular Pressure ; Prostheses and Implants ; Cataract

Glaucoma is one of the most common optic neuropathies, featuring progressive retinal ganglion cell damage and visual field loss (Tham et al., 2014; Xu et al., 2020). Currently, the only effective treatment for this condition is the reduction of intraocular pressure (IOP) (Palmberg, 2001; Heijl et al., 2002). Canaloplasty is a proven bleb-independent surgery with good efficacy and safety profiles in primary open-angle glaucoma (POAG) (Gołaszewska et al., 2021). However, early transient postoperative IOP elevation has been reported in up to 30% of cases (Riva et al., 2019), similar to that commonly observed in other internal drainage glaucoma surgeries such as implantation using iStent (0%-21.0%), CyPass (10.8%), and Hydrus (4.8%-6.5%) (Lavia et al., 2017). This complication may be a predictor of poor reserve in the outflow system and is potentially associated with surgical failure. Nonetheless, the exact pathophysiology of glaucoma remains unknown, and studies clarifying the risk factors for postoperative IOP elevation have been scarce.
Humans ; Intraocular Pressure ; Glaucoma, Open-Angle/surgery* ; Incidence ; Treatment Outcome ; Risk Factors

OBJECTIVE: To observe the clinical effect of acupuncture for glaucoma-induced optic atrophy. METHODS: A total of 70 patients (89 affected eyes) with glaucoma-induced optic atrophy were randomized into an observation group and a control group, 35 cases in each group. The control group was given basic western medicine treatment. In the observation group, on the basis of the treatment in the control group, acupuncture was applied at main acupoints i.e. Baihui (GV 20), Shangjingming (Extra), Chengqi (ST 1), Fengchi (GB 20), Zusanli (ST 36), combined with supplementary acupoints based on syndrome differentiation, once every three days, twice a week. The treatment for 3 months was required in both groups. Before treatment, after treatment and in follow-up of 6 months after treatment, the best corrected visual acuity (BCVA), intraocular pressure (IOP), indexes of visual field (visual field index [VFI], mean deviation [MD], pattern standard deviation [PSD]) and mean thickness of retinal nerve fiber layer (RNFL) were observed in the two groups. RESULTS: Compared before treatment, BCVA was decreased after treatment and in follow-up in the control group (P<0.05); in the follow-up, BCVA in the observation group was higher than that in the control group (P<0.05). On each time point before and after treatment, there was no significant difference within or between the two groups (P>0.05). After treatment and in the follow-up, the mean thickness of RNFL was larger than the control group (P<0.05). CONCLUSION On the basis of the basic western medicine treatment, acupuncture can delay the decline of vision and the thinning of retinal nerve fiber layer in patients with glaucoma-induced optic atrophy.
Humans ; Retinal Ganglion Cells ; Glaucoma/therapy* ; Optic Atrophy/therapy* ; Intraocular Pressure ; Acupuncture Therapy

The detection and dynamic monitoring of intraocular pressure have important clinical significance for the diagnosis and treatment of glaucoma. The current status of clinical intraocular pressure detection and dynamic intraocular pressure monitoring are reviewed. The technical challenges encountered, and the shortcomings of the existing technology are analyzed, in order to expect better intraocular pressure monitoring technology to be applied to patients.
Glaucoma/diagnosis* ; Humans ; Intraocular Pressure ; Technology ; Tonometry, Ocular

The treatment of refractory Glaucoma is a difficult problem in clinical ophthalmology. For refractory glaucoma patients with hyphema, shallow anterior chamber, anterior conglutination of peripheral chamber angle, corneal endothelium dystrophy or decompensated, at present, there is no effective treatment. In order to solve this problem, a new type posterior integral glaucoma valve with IOP control device was designed using medical titanium alloy, and the valve model was established by Abaqus software, and the stiffness and preload of the valve were analyzed by finite element method. The results showed that the opening and closing of the valve were controlled automatically by the pressure difference between the front and back of the valve, and the opening and flow rate of the valve increase dynamically with the increase of intraocular pressure, and finally reached the set ideal IOP value of steady state.
Finite Element Analysis ; Follow-Up Studies ; Glaucoma ; Glaucoma Drainage Implants ; Humans ; Intraocular Pressure ; Treatment Outcome

Objectives: We described the demographic and clinical profiles of patients with carotid-cavernous fistula (CCF), determined the prevalence of increased intraocular pressure (IOP), and described the IOP outcomes after endovascular treatment. Methods: This was a single-center, retrospective review of records of patients with clinical signs and radiologic evidence of CCF from January 2012 to December 2017. Outcome measures included the prevalence of increased IOP in those with CCF, mean and range of IOPs, average number of IOP-lowering medications needed, and percentage of eyes with normal, controlled, and uncontrolled IOP before and after endovascular intervention. Results: Ninety-six (96) eyes of 92 patients with radiologic evidence of CCF on 4-vessel cerebral angiography were included. Fifty-nine (59) percent were between the ages of 20 to 39 years. Majority (65%) were males. Direct CCFs accounted for 70% of cases. Increased IOP was the third most common ocular sign with a prevalence of 78%, ranging from 10 to 56 mmHg (mean 20.3 ± 8.0). The average number of antiglaucoma medications for IOP control was 2. Eleven (11) underwent definitive management for CCF. Post-treatment, 33% of 13 eyes had normal, 27% controlled, and 40% uncontrolled IOPs. Conclusion There was a high prevalence of increased IOP in patients with CCF. Those who did not achieve IOP control should be referred for endovascular intervention to prevent serious complications, including secondary glaucoma.
Intraocular Pressure