Experimental intracerebral mass: description of model, intracranial pressure changes and neuropathology.

In a rodent model designed to replicate the mass effects of spontaneous intracerebral hemorrhage, we have found that there is little change in intracranial pressure (ICP) with microballoons (25 microliters and 50 microliters in volume) equivalent in size to those lesions which occur with this disorder in man. With larger volumes (100 microliters) there is an increase in ICP which is associated with systemic effects on cerebral perfusion pressure (CPP). Neuropathological evidence of ischemic brain damage was found surrounding the mass in all animals, but this was independent of whether the mass was removed or not. These studies suggest that with a mass that corresponds to the size seen most commonly with spontaneous intracerebral hemorrhage in man, focal ischemic brain damage is produced without reduction in global CPP.