Prediction Of Hemorrhagic Transformation In Early Ischemic Infarction Using DWI And PWI

Objective:Objective is to explore the relationship between imaging changes (DWI and PWI) and hemorrhagic transformation of early cerebral infarction.Methods:I collected 58 patients (18women,40men,aged 35-89years,the average age of 64.8 years) with ischemic infarction (3h～3d),who came to hospital with symptoms of dizziness,limb weakness,slurred speech and other symptoms. All patients underwent MRI examination, including T1WI,T2WI,DWI,PWI and 3D SWAN, and all patients were rechecked MR scans within a half month after treatment.There was a total of 136 times of MRI (including 21 cases received PWI examination at the time of initial MRI examination). And then 58 patients were divided into hemorrhagic transformation (HT) group and the group without hemorrhagic transformation (NHT) group.HT diagnostic criteria was that blood signal within infarction lesion can be seen in 3D SWAN sequence (low signal). (1) I calculated the number of cases of HT,and recorded the imaging classification and clinical symptom;(2) I measured volume,ADC value and rADC value of the initial infarct lesions in DWI;(3) I measured the initial PWI perfusion (rCBV value) in infarct lesion and surrounding infarction.Statistical analyses were made by using SPSS statistical package, measuring data compared with t test,ranked data compared with Mann-Whitney U test,related factors were analyzed by multivariate Logistic regression analysis,P<0.05 was considered statistically significant.Results:1. Among the 58 patients,28 cases had hemorrhagic transformation (HT group),and 30 cases were without hemorrhagic transformation (NHT). The follow-up found that the imaging types of HI1 and HI2 were common, and the imaging types were related to the clinical symptom of HT.2. After statistical analysis,infarct volume between the two groups of patients,the minimum ADC value,rADC value and the average ADC values of infarction was statistically significant.3. Logistic regression analysis were applied with forward LR,infarct volume,ADC values and perfusion was related to the occurrence of HT,and finally mean ADC value come into the equation,considered as the independent factor of HT. The average ADC value was a protective factor,OR=0.014,P=0.002. Using receiver operating curve characteristic (ROC) to evaluate the predictive value of HT with the average ADC value,with the cutoff point≤450×10-6 mm2/s,the sensitivity and specificity were both higher,respectively,0.833 and 0.750,ROC area under the curve was 0.841,95% CI:(0.734,0.948).4.21 early cerebral infarction patients received PWI examination.11 cases had hemorrhagic transformation (HT group),and 10 cases were without hemorrhagic transformation (NHT). After statistical analysis, the perfusion in infarct lesion and surrounding infarction was statistically different between HT group and NHT group. In HT group, patients were mostly hypoperfusion infarction,and peripheral perfusion increased (collateral circulation);in NHT group,infarct lesions were mostly mild hypoperfusion infarction or even increase slightly,and the perfusion around the infusion may be normal or abnormal.Conclusion:1. The follow-up found that the imaging types of HI1 and HI2 were common,and the hemorrhagic types were related to the clinical symptom of HT2. Infarct volume, ADC values and perfusion was related to the occurrence of HT,and the average ADC value was a independent factor of hemorrhagic transformation,the cutoff point to predict HT was≤450×10-6 mm2/s.3. DWI and PWI had predictive significance of hemorrhagic cerebral infarction:cerebral infarction with large infarct volume,ADC values gravely decreased,hypoperfusion infarction with collateral circulation around,the risk of HT was higher;and small infarction,ADC values gently decreased,slightly reduced infarct perfusion and even increased,the risk of HT was smaller. Early cerebral infarction patients with high risk of HT could be rechecked CT or MRI examination one to two weeks later to make sure whether there was HT or not, so doctors can understand the disease well and adjust the treatment promptly.