A microstructural study of spinal cord edema.

Abstract

The experimental spinal cord edema was produced in a cat by the infusion method of Marmarou. Horseradish peroxidase (HRP) dissolved in autoserum of a cat was used as a tracer. After laminectomy, a 30-gauge needle was inserted into the intumescentia cervicalis. A total amount of 20 microliters of a tracer was infused at a rate of 10 microliters/hr. The structural features were studied immediately and 3 days after infusion. Immediately after infusion, HRP was noted in the infused white and gray matters. Though the perivascular space in the white matter at the infused site was widely distended and filled with HRP, the space in the gray matter was not distended but filled with HRP. HRP which was observed along vessels led to the surface of the spinal cord. Swelling of astrocyte was not observed. Three days after infusion, the extracellular space and the perivascular space in the infused white matter were still expanded but were not filled with HRP. The fine structural features were similar to the findings as seen in Marmarou's infusion type of brain edema. Using this model, it seems to be feasible to study the resolution process of spinal cord edema.