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The Effects of Prostaglandin Analogs on Intraocular Pressure in Human Eye for Open Angle Glaucoma

Shabab Akbar, Sapna Ratan Shah
Aqueous humor is an outflow, which flows at the back of the iris in the posterior chamber all the way through the pupil aperture, out into the anterior chamber, and drain from the eye via drainage slope  ...  channels" and due to the less amount of aqueous humor fluid flow from the drainage angle, the pressure in the eye starts to increase.  ...  ACKNOWLEDGEMENT The authors would like to thank the School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi-110067, (India) for providing facility of Bio mathematical Lab  ... 
doi:10.35940/ijitee.a8195.1210220 fatcat:barympx5qzfwll46cg5iniq55q

Fluid and structure coupling analysis of the interaction between aqueous humor and iris

Wenjia Wang, Xiuqing Qian, Hongfang Song, Mindi Zhang, Zhicheng Liu
2016 BioMedical Engineering OnLine  
The purpose here was to study the effect of IOP, localization, and temperature on the flow of the aqueous humor and the deformation of iris interacted by aqueous humor fluid flow.  ...  So far the FSI analysis was carried out in that idealization geometry model of anterior segment to study aqueous flow and iris change.  ...  Availability of data and materials Data available upon request.  ... 
doi:10.1186/s12938-016-0261-3 pmid:28155692 pmcid:PMC5260046 fatcat:66gumxt6p5gpvnhnnhwiynksci

The flow of aqueous humor in the human eye

R F Brubaker
1982 Transactions of the American Ophthalmological Society  
ACKNOWLEDGMENTS This study was supported by Grant EY 00634 of the National Eye Institute, by Research to Prevent Blindness, by the Rowland Foundation, by the Grover Hermann Foundation, by Mr J. K.  ...  Kirgis assisted with the preparation of the manuscript.  ...  A correlation is also found between flow and anterior chamber volume; the larger the anterior chamber volume the greater the rate of aqueous humor flow.  ... 
pmid:6763801 pmcid:PMC1312276 fatcat:txtlksfrynckznxbsddfhqrshq

A contemporary concept of the blood–aqueous barrier

Thomas F. Freddo
2013 Progress in retinal and eye research  
The Classical model simply stipulated that the tight junctions of the iris vasculature and ciliary epithelium excluded plasma proteins from the aqueous humor (AH).  ...  The one-way valve created by the pupil resting on the anterior lens capsule, combined with the continuous, forward flow of AH through the pupil, prevents protein reflux into the posterior chamber.  ...  Acknowledgments The work of the author cited in this article has been supported by NIH RO1 EY-04567, RO1 EY-13825 to TFF, by  ... 
doi:10.1016/j.preteyeres.2012.10.004 pmid:23128417 pmcid:PMC3544162 fatcat:762gmulaeza5zpxfxncz3rnqdu

In Vivo Assessment of Aqueous Humor Dynamics Upon Chronic Ocular Hypertension and Hypotensive Drug Treatment Using Gadolinium-Enhanced MRI

Leon C. Ho, Ian P. Conner, Chi-Wai Do, Seong-Gi Kim, Ed X. Wu, Gadi Wollstein, Joel S. Schuman, Kevin C. Chan
2014 Investigative Ophthalmology and Visual Science  
Gadolinium contrast agent was systemically administered to adult rats to mimic soluble AH components entering the anterior chamber (AC) via blood-aqueous barrier.  ...  Although glaucoma treatments alter aqueous humor (AH) dynamics to lower intraocular pressure, the regulatory mechanisms of AH circulation and their contributions to the pathogenesis of ocular hypertension  ...  Gadolinium MRI may also allow evaluation of the efficacy of antiglaucoma agents through longitudinal monitoring of the aqueous humor flow in vivo.  ... 
doi:10.1167/iovs.14-14263 pmid:24764067 pmcid:PMC4062398 fatcat:kfgt4xn2pva75fht3ft6kcdewa

Phakic Iris-Fixated Intraocular Lens Placement in the Anterior Chamber: Effects on Aqueous Flow

Rodolfo Repetto, Jan O. Pralits, Jennifer H. Siggers, Paolo Soleri
2015 Investigative Ophthalmology and Visual Science  
Phakic iris-fixated intraocular lens placement in the anterior chamber: effects on aqueous flow. PURPOSE.  ...  We use a mathematical model to study fluid flow in the anterior chamber in the presence of a pIOL. The governing equations are solved numerically using the open source software OpenFOAM.  ...  MATERIALS AND METHODS Description of the Model In this paper we develop a mathematical model to study the flow of aqueous humor in the anterior chamber with a pIOL.  ... 
doi:10.1167/iovs.14-16118 pmid:26024090 fatcat:p3h2efuapjahpmqky2te2mw7ka

Characterizing the Aging Process of the Human Eye: Tear Evaporation, Fluid Dynamics, Blood Flow, and Metabolism-Based Comparative Study

Md Ashiqur Rahman, Mamun Rabbani, Md Hasan Maruf, Aminul Islam, A. S. M. Shihavuddin, Ali A. Khraibi
2022 BioMed Research International  
All the three simulation parameters of this study, the temperature of the human eye, the intraocular pressure, and the aqueous humor flow velocity, have been compared with the recent practical and simulation-based  ...  The rate of temperature change is – 0.0075 K per year in the standing position and – 0.007 K per year in the supine position because of the modeled anatomical and physiological effects.  ...  T amb = 294K Figure 12 : 12 Figure 12: Velocity magnitude of the aqueous humor flow in the anterior and posterior chamber: (a)-(c) young eye in the horizontal position, (d)-(f) elder eye in the horizontal  ... 
doi:10.1155/2022/2805402 pmid:35372570 pmcid:PMC8970893 fatcat:7prsbjygjjbelf7dromdzbqtle

GD-DTPA enhanced MRI of ocular transport in a rat model of chronic glaucoma

Kevin C. Chan, Qing-ling Fu, Hua Guo, Kwok-fai So, Ed X. Wu
2008 Experimental Eye Research  
Further, there was an earlier Gd-DTPA transport into the anterior chamber in the majority of glaucomatous eyes.  ...  While this elevated pressure is related to an increased resistance to the outflow of aqueous humor from the eye, their impacts to the etiology and pathogenesis of the disease are not fully understood.  ...  Acknowledgments This work was supported in part by Hong Kong Research Grant Council and The University of Hong Kong CRCG grant.  ... 
doi:10.1016/j.exer.2008.06.015 pmid:18639546 fatcat:jjg7b3ah7vavdf43jlidbpc45e

A model to measure lymphatic drainage from the eye

Minhui Kim, Miles G. Johnston, Neeru Gupta, Sara Moore, Yeni H. Yücel
2011 Experimental Eye Research  
Intraocular pressure (IOP) is the most important risk factor for glaucoma development and progression. Most anti-glaucoma treatments aim to lower IOP by enhancing aqueous humor drainage from the eye.  ...  The relative contribution of the lymphatic pathway to aqueous drainage is not known. We developed a sheep model to quantitatively assess lymphatic drainage along with TM and UVS outflows.  ...  From the anterior chamber, the aqueous humor leaves the anterior chamber of the eye by bulk flow via two pathways at the anterior chamber angle: conventional outflow (pressure-dependent) and another unconventional  ... 
doi:10.1016/j.exer.2011.07.006 pmid:21810424 fatcat:utft3lpt4nfl7iuuqlmpcb6vhy

Extended Pharmacokinetic Model of the Rabbit Eye for Intravitreal and Intracameral Injections of Macromolecules: Quantitative Analysis of Anterior and Posterior Elimination Pathways

Marko Lamminsalo, Ella Taskinen, Timo Karvinen, Astrid Subrizi, Lasse Murtomäki, Arto Urtti, Veli-Pekka Ranta
2018 Pharmaceutical Research  
Methods The computational fluid dynamic model of the rabbit eye by Missel (2012) was extended by enhancing the mixing in the anterior chamber with thermal gradient, heat transfer and gravity, and studying  ...  humor (anterior chamber) Cv mean concentration of macromolecule in the vitreous CFD computational fluid dynamics Vv volume of the vitreous  ...  Missel for his advice during our model building and his suggestion on how to improve the mixing in the anterior chamber, and Dr. Jeffrey W.  ... 
doi:10.1007/s11095-018-2435-0 pmid:29855726 fatcat:squpfrl3enbpzptomkvbeilsta

Regionally Discrete Aqueous Humor Outflow Quantification Using Fluorescein Canalograms

Ralitsa T. Loewen, Eric N. Brown, Pritha Roy, Joel S. Schuman, Ian A. Sigal, Nils A. Loewen, Pedro Gonzalez
2016 PLoS ONE  
In anterior chamber cultures, reduced flow on day 1 increased in all quadrants on day 3 except in IT (p<0.05). Perilimbal ring analysis uncovered convergent perilimbal flow.  ...  In whole eyes, significantly faster flow was seen in the inferonasal (IN) and superonasal (SN) quadrants compared to the superotemporal (ST) and inferotemporal (IT) ones (p<0.05).  ...  Discussion Conventional outflow of aqueous humor can be measured by fluorophotometry that analyzes the decreasing fluorescence of fluorescein in the anterior chamber.  ... 
doi:10.1371/journal.pone.0151754 pmid:26998833 pmcid:PMC4801333 fatcat:n4zor3qgezdk7k4rauj23xlnzq

Ion Movement in the Eye

1960 Circulation  
The rate of flow of the secreted fluid into the posterior chamber. 3. The rate of flow of the aqueous humor from the posterior chamber to the anterior chamber. 4.  ...  Table 2 Symbol Designation Units Any Area of posterior chamber—vitreous interface em.” a Donnan factor C, Concentration in aqueous humor of anterior chamber Ch Concentration in aqueous humor of posterior  ... 
doi:10.1161/01.cir.21.5.968 pmid:14409244 fatcat:tizfgsrp7vdqzhgorlv36a363m

Dynamic contrast-enhanced MRI of ocular biotransport in normal and hypertensive eyes

Kevin C. Chan, Qing-ling Fu, Kwok-fai So, Ed X. Wu
2008 2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society  
Further, there was an earlier Gd-DTPA transport into the anterior chamber in the majority of glaucomatous eyes.  ...  Upon systemic administration of Gd-DTPA solution, T1-weighted signal increase was observed in the vitreous body of the glaucomatous eye but not the control eye.  ...  Protein concentration in the anterior chamber of normal eyes has been identified to be determined by the rate of protein entry into the aqueous humor, the removal rate by bulk flow of aqueous humor, and  ... 
doi:10.1109/iembs.2008.4649283 pmid:19162786 fatcat:fka6k7hhcjbsjm7oqpfeeiguqm

Nitric oxide levels in the aqueous humor vary in different ocular hypertension experimental models

Da-Wen Lu, Yi-Hao Chen, Charn-Jung Chang, Chiao-Hsi Chiang, Hsin-Yu Yao
2014 Kaohsiung Journal of Medical Sciences  
On postinduction Day 7, the aqueous humor NO levels increased significantly in the models of a-chymotrypsin, Polybead, and red blood cell ghosts (all p < 0.01), while the aqueous flow rates were significantly  ...  The Polybead model exhibited the characteristic of an increased aqueous humor NO level, similar to human eyes with acute angle-closure glaucoma and neovascular glaucoma.  ...  Acknowledgments This research work was partially supported by National Science Council grants (89-2314-B-016-011 and 89-2314-B-016-070) and was utilized to fulfill the dissertation requirement for C.J.C  ... 
doi:10.1016/j.kjms.2014.09.004 pmid:25476096 fatcat:uvjlfpwpkng4nkwrzfkb3lt2cq

A Mathematical Model of Corneal Metabolism in the Presence of an Iris-Fixated Phakic Intraocular Lens

Peyman Davvalo Khongar, Jan O. Pralits, Xi Cheng, Peter Pinsky, Paolo Soleri, Rodolfo Repetto
2019 Investigative Ophthalmology and Visual Science  
A mathematical model of transport and consumption/production of metabolic species in the cornea is proposed, coupled with a model of aqueous flow and transport of metabolic species in the anterior chamber  ...  A mathematical model of corneal metabolism in the presence of an iris-fixated phakic intraocular lens. Invest Ophthalmol Vis Sci. 2019;60:2311-2320. 10.1167/iovs.19-26624 PURPOSE.  ...  of the aqueous in the anterior chamber. 10 This flow also exists with a similar intensity in the presence of a PIOL. 4, 11 Moreover, daytime eye rotations also generate significant velocities and mixing  ... 
doi:10.1167/iovs.19-26624 fatcat:yveup5h5f5enrfbt4k4q4irdt4
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