Qi Li^1,2, Ningli Wang³, Zhicheng Liu^1,2, Lin Li^1,2, Zhicheng Liu^1,2, Wenjia Wang^1,2, Xiaoxue Long^1,2, Hongfang Song^1,2,*

Molecular & Cellular Biomechanics, Vol.17, No.3, pp. 119-137, 2020, DOI:10.32604/mcb.2020.09529

Abstract Aim: To investigate the relationship between glaucoma and intraocular pressure (IOP), intracranial pressure (ICP), trans-laminar cribrosa pressure difference (TLCPD), and the newly proposed fractional pressure reserve (FPR). Methods: Ten articles were analyzed by meta-analysis, and subgroup analysis of three factors was conducted. Results: The patients with normal tension glaucoma (NTG) and open-angle glaucoma (OAG) have higher TLCPD and lower ICP than healthy subjects, with obvious heterogeneity. The greater heterogeneity may arise from different ICP measurements and from different countries or regions. FPR performs better than TLCPD in some ways. Conclusion: Both FPR and TLCPD can be used as indicators of… More >

Xiaofei Wang^1,2,*, Yubo Fan^1,2

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 112-112, 2019, DOI:10.32604/mcb.2019.07053

Abstract Accommodation is the ability of the eye to adjust its lens thickness to alter the refractive power through the contraction of ciliary muscles. The loss of accommodation ability due to aging leads to presbyopia, a condition in which the eye is unable to focus on near objects. Glaucoma is a disease that vision is impaired due to damage of the retinal ganglion cell at the optic nerve head (ONH) region, which is the leading cause of irreversible blindness worldwide. The biomechanical theory of glaucoma suggests that the deformations of ONH tissues could (directly or indirectly) drive retinal ganglion cell death.… More >

Claudia G. REIDES^1,2, Romina M. LASAGNI VITAR^1,2, Agustina PEVERINI¹, Natasha S. JANEZIC¹, Ailen G. HVOZDA ARANA¹, Sandra M. FERREIRA^1,2, Susana F. LLESUY^1,2*

BIOCELL, Vol.40, No.1, pp. 51-54, 2016, DOI:10.32604/biocell.2016.40.051

Abstract The purpose of this study was to evaluate the redox status changes of primary visual targets in the rat brain of a high pressure-induced glaucoma model. The animal model consisted of inducing ocular hypertension by cauterizing two episcleral veins on the left eye. The markers of oxidative damage and the oxidative balance evaluated in the brain seven days postoperative were: nitrites concentration, levels of non-enzymatic antioxidants and antioxidant enzymes activity.
The increase in the nitrite content, which could be the result of the enhancement in the production of nitrogen species, and in the activity of NADPH oxidase in the glaucoma… More >

David CC LAM^*, Leo K-K LEUNG, Match W-L KO, R. G-Z CHEN, I-S CHAN

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.3, pp. 85-86, 2011, DOI:10.3970/icces.2011.020.085

Abstract The eye is a biomechanical organ where the health of the optical nerves and vision are affected by the intrCular pressure and the ocular tissue structure. The ocular pressure is the primary parameter monitored by opticians and ophthalmologists to determine the ocular health of the eye to prevent glaucoma where 50% of the vision can be lost before detection by the patient. Elevated intrCular pressure is clinically correlated with the degeneration of the optic nerves, but the biomechanical mechanism for the degeneration remains speculative. In this study, we present the results from biomechanical modeling of nerve damage as a function… More >

Wenjia Wang^{1, 2}, Xiuqing Qian^{1, 2}, Qi Li^{1, 2}, Gong Zhang^{1, 2}, Huangxuan Zhao^{1, 2}, Tan Li^{1, 2}, Yang Yu^{1, 2}, Hongfang Song^{1, 2, *}, Zhicheng Liu^{1, 2, *}

Molecular & Cellular Biomechanics, Vol.16, No.1, pp. 59-74, 2019, DOI:10.32604/mcb.2019.06393

Abstract Pupillary block is considered as an important cause of primary angle-closure glaucoma (PACG). In order to investigate the effect of pupillary block on the hydrodynamics of aqueous humor (AH) in anterior chamber (AC) and potential risks, a 3D printed eye model was developed to mimic the AH flow driven by fluid generation, the differential pressure between AC and posterior chambers (PC) and pupillary block. Particle image velocimetry technology was applied to visualize flow distribution. The results demonstrated obvious differences in AH flow with and without pupillary block. Under the normal condition (without pupillary block), the flow filed of AH was… More >

Mahesh B. Mawale^1,*, Abhaykumar Kuthe², Dr. Padma Pawane³, Sandeep W. Dahake², Jyotilal S²

Molecular & Cellular Biomechanics, Vol.13, No.2, pp. 105-114, 2016, DOI:10.3970/mcb.2016.013.119

Abstract Purpose: The main purpose of this study is to develop a device for the indicative measurement of intraocular pressure (IOP) of eyeball, a key cause for glaucoma. In early diagnosis and treatment of glaucoma accurate measurement of IOP is important. The methods and devices which are available for the measurement of IOP have their own limitations which cause discomfort to the patients during measurement and needs anesthesia. There is a dare need of a device for the measurement of intraocular pressure by making the contact of plunger with closed eyelid eliminating the need of anesthesia and expert ophthalmologist. Method: Additive… More >

Match W L Ko^∗, Leo K K Leung^∗, David C C Lam^∗,†

Molecular & Cellular Biomechanics, Vol.9, No.4, pp. 251-268, 2012, DOI:10.3970/mcb.2012.009.251

Abstract Inter-individual differences in corneal properties are ignored in existing methods for measuring intraocular pressure IOP, a primary parameter used in screening and monitoring of glaucoma. The differences in the corneal stiffness between individuals can be more than double and this difference would lead to IOP measurement errors up to 10 mmHg. In this study, an instrumented partial-contact indentation measurement and analysis method that can account for inter-individual corneal difference in stiffness is developed. The method was tested on 12 porcine eyes ex vivo and 7 rabbit eyes in vivo, and the results were compared to the controlled IOPs to determine… More >

Leo KK Leung^∗, Match WL Ko^∗, David CC Lam^†

Molecular & Cellular Biomechanics, Vol.9, No.2, pp. 157-174, 2012, DOI:10.3970/mcb.2012.009.157

Abstract Age-stiffening of ocular tissues is statistically linked to glaucoma in the elderly. In this study, the effects of age-stiffening on the lamina cribrosa, the primary site of glaucomatous nerve damages, were modeled using computational finite element analysis. We showed that glaucomatous nerve damages and peripheral vision loss behavior can be phenomenologically modeled by shear-based damage criterion. Using this damage criterion, the potential vision loss for 30 years old with mild hypertension of 25mmHg intraocular pressure (IOP) was estimated to be 4%. When the IOP was elevated to 35mmHg, the potential vision loss rose to 45%; and age-stiffening from 35 to… More >

Weijuan Yao^*, Lanping Amy Sung^†

Molecular & Cellular Biomechanics, Vol.6, No.1, pp. 71-82, 2009, DOI:10.3970/mcb.2009.006.071

Abstract Erythrocyte tropomodulin (E-Tmod) is a tropomyosin-binding and actin capping protein at the point end of the filaments. It is part of a molecular ruler that plays an important role in generating short actin protofilaments critical for the integrity of the cell membrane. Here, with the use of \textit {E-Tmod+/lacZ} mice, we demonstrated a specific E-Tmod expression in horizontal cells (HCs) in the retina, and analyzed the stress-strain relationship of HCs, vertically oriented neurons, and retinal ganglial cells (RGC) under normal and high intraocular pressure (IOP). Since their dendrites are oriented laterally in a plane and form most complicated synapses with… More >

Arthur J. Sit^*, John H.K. Liu^†

Molecular & Cellular Biomechanics, Vol.6, No.1, pp. 57-70, 2009, DOI:10.3970/mcb.2009.006.057

Abstract Glaucoma is a leading cause of visual impairment and blindness worldwide. The main risk factor for glaucoma is an elevated intraocular pressure (IOP), which is also the only currently treatable risk factor. Despite its importance, our understanding of IOP is incomplete and our ability to measure IOP is limited. IOP is known to undergo both random fluctuations as well as variations following a circadian pattern. In humans, IOP is highest at night and lower during the daytime, largely due to changes in body position, although other factors appear to contribute. In rabbits, IOP is also highest at night and lower… More >