The known cytoprotective properties of MgSO4 led the authors to study its effects on infarct size in rats when administered intraarterially before reversible focal ischemia. Following an intracarotid infusion of MgSO4 in the amount of 30 mg/kg (24 animals), 90 mg/kg (18 animals), or an equal volume of vehicle (23 animals), middle cerebral artery occlusion was produced in rats by means of an intraluminal suture technique. Reperfusion occurred after 1.5 (42 animals) or 2 hours (23 animals) of ischemia. Automated, volumetric measurements of 2',3',5'-triphenyl-2H-tetrazolium chloride-stained coronal brain sections demonstrated a statistically significant decrease in infarct size for MgSO4 treatment groups compared to controls. Cytoprotection was greater in animals subjected to 1.5 hours of ischemia (28.4% reduction in infarct volume, p < 0.001, Student's t-test), than in those having 2 hours of ischemia (19.3% reduction, p < 0.05). Animals given 90 mg/kg MgSO4 prior to 1.5 hours of ischemia (12 animals) showed a 59.8% reduction in infarct volume compared to controls (11 animals, p < 0.001) and a 43.1% reduction compared to the 30 mg/kg group (11 animals, p < 0.001). Analysis of variance demonstrated the statistically significant effects of MgSO4 doses on infarct volume across all groups (F = 22.95, p < 0.0001). The neuroprotective effect of intraarterial MgSO4 in this model is robust, dose dependent, and related to the duration of ischemia. The compound may be valuable for limiting infarction if given intraarterially before induction of reversible ischemia during cerebrovascular surgery.

No unique morbidity is associated with extremes of subaxial decompression when compared with surgery of lesser extent.

Based on this analysis, microsurgical treatment of Grades I to III AVMs is superior to stereotactic radiosurgery.

As we have previously reported, logistic regression analysis determined that grade of hemorrhage was the only significant predictor of cognitive and motor outcomes. Most premature neonates with massive intracranial hemorrhages do not survive. The outcomes in those who do is very poor and the cost so high that we suggest that until therapeutic intervention exhibits efficacy, the consideration of withdrawal of life support should be presented as an option to the parents of these unfortunate children.