Randles Model of Vitreous Humor

Tjerignimin Silue, Saugandhika Minnikanti, Nathalia Peixoto

Abstract

The vitreous is a gel-like structure found in the eyes. It is located above the retina to prevent the passage of fluids. As aging occurs, the vitreous can liquefy and can cause retinal detachment. The literature has little characterization of the vitreous, as it is often a less interesting structure than the retinal tissue. We investigate the impedance properties of the stimulation electrodes such as the constant phase element (Q) and the resistance of the solution (Rsol). We show results on vitreous characterization through electrochemical methods as a first step toward understanding the role of electrical stimulation in retinal prosthetics applications as it pertains to vitreous liquefaction. Our objective is to characterize the vitreous for a wide frequency range and to determine how charge is distributed through its conductive structure. Our electrochemical experiments were performed using insulated stainless steel electrodes (1) in phosphate buffered saline (PBS) and (2) in thimerosal as controls, (3) in vitreous without thimerosal, as well as (4) in vitreous preserved with thimerosal. We also performed cyclic voltammetry to measure the cathodic charge storage capacity for the electrodes for all experimental groups. Our results showed that the resistivity of the vitreous increases as thimerosal is added and that the cathodic charge storage capacity of the vitreous does not show any significant difference in the means as thimerosal is added.

References

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Paper Citation


in Harvard Style

Silue T., Minnikanti S. and Peixoto N. (2017). Randles Model of Vitreous Humor . In Proceedings of the 10th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 1: BIODEVICES, (BIOSTEC 2017) ISBN 978-989-758-216-5, pages 156-162. DOI: 10.5220/0006166001560162


in Bibtex Style

@conference{biodevices17,
author={Tjerignimin Silue and Saugandhika Minnikanti and Nathalia Peixoto},
title={Randles Model of Vitreous Humor},
booktitle={Proceedings of the 10th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 1: BIODEVICES, (BIOSTEC 2017)},
year={2017},
pages={156-162},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0006166001560162},
isbn={978-989-758-216-5},
}


in EndNote Style

TY - CONF
JO - Proceedings of the 10th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 1: BIODEVICES, (BIOSTEC 2017)
TI - Randles Model of Vitreous Humor
SN - 978-989-758-216-5
AU - Silue T.
AU - Minnikanti S.
AU - Peixoto N.
PY - 2017
SP - 156
EP - 162
DO - 10.5220/0006166001560162