Muller Cell Culture in-vitro Experiments of Biochemically Modified Surfaces as a Fixation Concept for Epiretinal Stimulator Arrays

Abstract

Purpose: : At present, fixation procedures utilising retinal tacks ensure a sufficient connection of the prosthesis onto the retinal surface. As an alternative to this potentially traumatic procedure we developed biochemical modifications of the array surface which may lead to a direct connection of the modified stimulating foil to surface signals of the retina.

Methods: : Polyimide microstructures were coated by chemical vapor deposition (CVD) polymerisation. Hexamethylendiisocyanate (HDI) was used as a spacer to provide immobilization and binding of the different protein configurations to the CVD coating. Muller cell cultures were used to demonstrate biocompatibility of the CVD coating and the binding capacity to different protein configurations with special regard on cell adhesion, vitality, morphological features and mitosis.

Results: : Surface modifications with immobilized Laminin composite coatings showed good adhesion to retinal Muller cells in vitro. In regard to biocompatibility cell morphology and vitality did not show remarkable alterations.

Conclusions: : In vitro experiments may prove the biocompatibility of the different coating configurations as well as we could identify potential protein surface modifications for in vivo testing. Animal experiments including clinical, functional and histological examinations may demonstrate the feasibility of this method as an alternative to conventional fixation procedures.

Keywords: retinal degenerations: hereditary • retina: proximal (bipolar, amacrine, and ganglion cells) • retinal culture