A new model of spinal cord edema

Edema of the spinal cord has not been well understood. Brain edema produced by Marmarou's infusion method is essentially similar to vasogenic edema. This infusion method for producing edema was applied to a cat spinal cord. After laminectomy, a 30-gauge needle was inserted into the intumescentia cervicalis. A total amount of 10 microliters of 2% Evans' blue or autoserum were infused using an infusion pump at a rate of 5 microliters/hr. Macroscopally, Evans' blue was observed in the vicinity of infused site at the same level of the needle insertion and was seen spreading mainly longitudinally in the lateral column for a certain distance. The extracellular space was markedly distended in the in fused white mater and filled with electron-dense materials which were thought to be proteins in the electron microscopic study. The fine structural features were similar to the findings which were seen in Marmarou's infusion type of brain edema. Using this model, it seems to be feasible to produce reproducible spinal cord edema at any location in order to investigate not only the morphological aspect but also physiological aspect of the edema.