SciELO - Scientific Electronic Library Online

 
vol.34 issue3In-flight collision avoidance controller based only on OS4 embedded sensorsA study of convective flux schemes for aerospace flows author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Journal of the Brazilian Society of Mechanical Sciences and Engineering

Print version ISSN 1678-5878

Abstract

SILVA, G. M. L. L. da et al. The use of an axisymmetric formulation of the Finite Volume Method for the thermal analysis of the retina and ocular tissues following implantation of retinal prosthesis. J. Braz. Soc. Mech. Sci. & Eng. [online]. 2012, vol.34, n.3, pp. 308-313. ISSN 1678-5878.  http://dx.doi.org/10.1590/S1678-58782012000300011.

This study analyzes the heat transfer in human eyes following implantation of retinal prostheses using an axisymmetric formulation of the Finite Volume Method. The model used consisted of a vertex centered unstructured grid finite volume method in an edge-based data structure and an explicit time integration. The results of the finite volume thermal analysis in ocular tissues were determined in the presence of two types of retinal implants: subretinal and epiretinal. For the subretinal device, the maximum temperature reached in the retina was 36.78°C (309.78 K) and the irreversible thermal damage occurred at 200 days. In the case of the epiretinal implant, the maximum temperature reached at the retinal/chip interface was 36.92°C (309.92 K) and the irreversible thermal damage occurred at 180 days. Our results indicate that tin spite of its higher dissipation power, the epiretinal implant produces thermal damages similar to that caused by the subretinal implant. The computational tool which was developed was able to effectively calculate temperature profiles and thermal damage values to retinal implants and is also capable to calculate temperature profile in any other geometry of interest, for example with other types s of external thermal source like laser beans.

Keywords : finite volume method; axisymmetric models; hyperthermia; retina.

        · text in English     · pdf in English