Are Ranvier's nodes of the central nervous system also artifacts by preparation?

Recent research on peripheral nerves of six species of vertebrates concluded that Ranvier's nodes may be artifacts by preparation. As a consequence, the question as to whether or not Ranvier's nodes of the central nervous system may also be artifacts was logically raised. The ultrastructural data concerning our field of research (the cerebellar cortex) support the notion that Ranvier's nodes are real features in the central nervous system; otherwise, the occurrence of vesicular outpockets establishing, along myelinated axons, well conspicuous en passant nodal synapses cannot be explained.