CSF may be bloody with subarachnoid or cerebral hemorrhage, but is usually clear or slightly xanthochromic in infarcts. This patient is stabilized neurologically, but 24 hours after admission to the hospital suffers another massive myocardial infarction and dies. Gross examination of the brain at autopsy reveals lesions similar to those shown in slide L6, S6. Slide L6, S6 shows a gross photograph of a recent infarct in the distribution of the middle cerebral artery which is focally hemorrhagic. The gross changes are otherwise subtle at 24 hours.
Embolic infarcts are more likely to be hemorrhagic than thrombotic infarcts.
Both initially produce vascular occlusion, but emboli frequently are lysed and break up, allowing reperfusion of the ischemic area. Because the endothelial cells have also been injured by ischemia, the vessels become leaky and petechial or larger hemorrhages can develop. In thrombotic occlusion, the blockage is more likely to be permanent, and resulting in a bland, non-hemorrhagic infarct. This slide shows areas of infarcted brain tissue. Describe the pathologic changes.