We developed a new method using t-butyl alcohol in the microdissection of microvascular resin casts of the rat cerebral cortex for scanning electron microscopy. Brains injected with Mercox resin were eroded with sodium hypochlorite solution and dehydrated with graded ethanol. The resin casts obtained were embedded and frozen in t-butyl alcohol at 4 degrees C, and shaved through the planes of interest parallel to the brain surface with a razor blade. The sections were directly freeze-dried and coated with gold and platinum for scanning electron microscopy. Our method enables the demonstration of cross sections of the fine microvascular networks by SEM without any contamination or mechanical artifacts such as distortion and destruction.