Imperial College London
Portrait Picture

ProfessorDarrylOverby

Faculty of Engineering, Department of Bioengineering

Professor of Mechanobiology
 
 
 
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Contact

 

+44 (0)20 7594 6376d.overby

 
 
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Location

 

3.07Bessemer BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Madekurozwa:2017:10.1016/j.exer.2017.07.008,
author = {Madekurozwa, M and Reina-Torres, E and Overby, DR and Sherwood, JM},
doi = {10.1016/j.exer.2017.07.008},
journal = {Experimental Eye Research},
pages = {129--138},
title = {Direct measurement of pressure-independent aqueous humour flow using iPerfusion},
url = {http://dx.doi.org/10.1016/j.exer.2017.07.008},
volume = {162},
year = {2017}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Reduction of intraocular pressure is the sole therapeutic target for glaucoma. Intraocular pressure is determined by the dynamics of aqueous humour secretion and outflow, which comprise several pressure-dependent and pressure-independent mechanisms. Accurately quantifying the components of aqueous humour dynamics is essential in understanding the pathology of glaucoma and the development of new treatments. To better characterise aqueous humour dynamics, we propose a method to directly measure pressure-independent aqueous humour flow. Using the iPerfusion system, we directly measure the flow into the eye when the pressure drop across the pressure-dependent pathways is eliminated. Using this approach we address i) the magnitude of pressure-independent flow in ex vivo eyes, ii) whether we can accurately measure an artificially imposed pressure-independent flow, and iii) whether the presence of a pressure-independent flow affects our ability to measure outflow facility. These studies are conducted in mice, which are a common animal model for aqueous humour dynamics. In eyes perfused with a single cannula, the average pressure-independent flow was 1 [-3, 5] nl/min (mean [95% confidence interval]) (N = 6). Paired ex vivo eyes were then cannulated with two needles, connecting the eye to both iPerfusion and a syringe pump, which was used to impose a known pressure-independent flow of 120 nl/min into the experimental eye only. The measured pressure-independent flow was then 121 [117, 125] nl/min (N = 7), indicating that the method could measure pressure-independent flow with high accuracy. Finally, we showed that the artificially imposed pressure-independent flow did not affect our ability to measure facility, provided that the pressure-dependence of facility and the true pressure-independent flow were accounted for. The present study provides a robust method for measurement of pressure-independent flow, and demonstrates the importance of accurately quantifying this paramete
AU  - Madekurozwa,M
AU  - Reina-Torres,E
AU  - Overby,DR
AU  - Sherwood,JM
DO  - 10.1016/j.exer.2017.07.008
EP  - 138
PY  - 2017///
SN  - 0014-4835
SP  - 129
TI  - Direct measurement of pressure-independent aqueous humour flow using iPerfusion
T2  - Experimental Eye Research
UR  - http://dx.doi.org/10.1016/j.exer.2017.07.008
UR  - http://hdl.handle.net/10044/1/52812
VL  - 162
ER  -
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