structural:scholar_edition, structural:expansion
Hemorrhagic conversion of ischemic infarction

43% of those with infarcted brain tissue will develop hemorrhagic conversion. Risk of hemorrhagic is further increased with recanalisation of veins or arteries. Several types of hemorrhages can occur such as petechial hemorrhages around the infarcted margin (HI1), confluent petechial hemorrhages within the infarcted tissue (HI2), hematoma occupying less than 30% of the infarcted tissue (PH1), hematoma involving greater than 30% of infarcted tissue with small mass effect (PH2), and hematoma involving greater than 30% of the infarcted tissue with significant mass effect. However, only PH2 is clinically significant. Those who has infarction should be monitored frequently with CT brains to access hemorrhagic conversions or worsening vasogenic oedema that may require neurosurgical decompression. Dual energy CT scan maybe useful to differentiate the high densities caused by reperfusion hemorrhage (bleeding after endovascular stroke treatment) and high density due to iodinated contrast administered during cerebral angiography.