[Biodegradation of silicone drainage tubes in the efferent lacrimal system]

The authors present an account on their experience with biodegradation of silicone cannulas used for drainage of the efferent lacrimal system. They examined by means of a light microscope (enlargement up to 140 x) 38 cannulas, inserted into the lacrimal pathways for 1-7 months. They did not observe any biological damage of the surface of the cannula, not even when compared with non-exposed cannulas. Microbiological examination of six exposed cannulas did not reveal fungal infestation. The lacrimal pathways are not an aggressive environment for temporary cannulas.