Demonstration of Platinum Microcoils in Embolized Blood Vessels In-Situ Using a Modified Methyl Methacrylate Embedding Method, and a Special Cutting and Grinding Technique.

With current paraffin embedding techniques it is not possible to demonstrate metal particles in vascular lumens. We used a modified methyl methacrylate embedding method for obtaining plastic blocks which were cut with a precision diamond saw, and subsequently ground and polished to preserve the interface of reactive tissue surrounding platinum microcoils in arteriovenous malformations. Artifact-free interfaces could be achieved by slow embedding under vacuum conditions, slow polymerization in a water bath, and very gentle cutting, grinding and polishing techniques. The method produces good preservation of tissue and cells directly adjacent to metal coils. Our method is useful for the histomorphological interpretation of vascular pathologies in which metal particles have been introduced.