TRANSDURAL CORTICAL STABBING FACILITATES THE DRAINAGE OF EDEMA FLUID OUT OF COLD-INJURED BRAIN

Recent experimental results indicate that cerebral glia lining and gli a limitans may be barriers for plasma protein extravasated from injure d cerebral microvessels flowing into the adjacent subarachnoid space. Therefore, it has been hypothesized that a transdural cortical stabbin g which opens both the pia lining and glia limitans may facilitate dra inage of edema fluid into the subarachnoid space and minimize brain ed ema. This hypothesis was tested in Sprague-Dawley rats with a transdur al cold-injury on the right parietal cortex. The animals were sacrific ed 24 hours later. One hour before being sacrificed 0.6 ml of 2% Evans blue was intravenously injected to determining the Evans blue distrib ution area. For measuring the inulin retention volume in the brain, C- 14-inulin (10 muCi) in 1 ml of saline was injected intravenously at 10 min before sacrifice. The extent of brain edema was assessed by measu ring the water content, the inulin retention volume, and the distribut ion area of Evans blue in the brain. Our results showed that the trans dural cortical stabbing did not alter the water content of the cerebra l hemisphere with cold lesion. However, it did effectively diminish th e inulin retention volume by 26% as well as the distribution area of E vans blue by 22% in the cerebral hemisphere with cold lesion. In concl usion, a transdural cortical stabbing on the injured cortex may be ben eficial for vasogenic brain edema.