Histological response to injected Polytef and Bioplastique in the sheep brain

Abstract

Objective: To assess the histological response of the sheep brain to the intra-arterial injection of particulate plastic. Materials and methods: Four sheep had either polyte-trafluoroethyene-containing Polytef or silicone-containing Bioplastique injected into the left carotid artery under direct vision. Two were killed soon after and the others were studied at 6 months. The brains of the animals were examined using routine histology, phase contrast and polarized light. Results: The polytetrafluoroethylene or silicone particles were identified in the two animals killed soon after the injection, and the two animals examined 6 months later. There was no evidence of demyelination and only a minimal inflammatory response to the plastic particles which had found their way into the brain parenchyma. Conclusion: Demyelination does not occur in the sheep brain after intra-arterial injection of Polytef and Bioplastique, and inflammation occurs only to a minor degree.