[The combined application of magnetic resonance DTI and 3D-pcASL in differential diagnosis of hyper-acute and acute ischemic cerebral infarction].

Objective: To explore the clinical value of magnetic resonance diffusion tensor imaging (DTI) combined with 3D pseudo continuous arterial spin labeling (3D-pcASL) perfusion imaging in differential diagnosis of hyper-acute and acute ischemic cerebral infarction. Methods: A total of 42 patients with confirmed unilateral ischemic cerebral infarction from February 2015 to October 2017 of Affiliated Yancheng Hospital of Southeast University Medical College were collected. DTI and 3D-pcASL images of hyper-acute (14 patients, group A) and acute (28 patients, group B) ischemic cerebral infarction were retrospectively analyzed. The slice with the biggest lesion on diffusion weighted imaging (DWI) was selected to measure the infarction area (S(DWI)) and abnormal cerebral blood flow (CBF) perfusion area (S(CBF)). Regions of interest (ROIs) were set on the infarction core (IC) area, mismatch area of S(CBF) and S(DWI) (MACD), and their corresponding contralateral regions. The values of CBF, average diffusion coefficient (DC(avg)), and fractional anisotropy (FA) parameter images in these ROIs in patients with both S(CBF)>S(DWI) and lower perfusion in the IC were recorded. The relative values of each infarction lesion to its corresponding contralateral region (rCBF, rFA, and rDC(avg)) were calculated. Differences of each parameter value between the IC, MACD and their corresponding contralateral regions and of the relative values between group A and group B were investigated. Results: The CBF and DC(avg) values in the IC and the CBF value in the MACD were lower than that of their corresponding contralateral regions in both groups ( P <0.05). The DC(avg) in the MACD in group A patients and the FA in the IC in group B patients were lower than that in their corresponding contralateral regions ( P <0.05). Compared to group A patients, group B patients showed decreased rFA, rDC(avg) in the IC and rFA in the MACD, and increased rDC(avg) and rCBF in the MACD ( P <0.05). Receiver operating characteristics (ROC) curve analysis indicated that the best diagnosis cut off values of the rFA and rDC(avg) values in the IC and the rCBF, rFA, and rDC(avg) values in the MACD were 0.890 and 0.541 and 1.139, 0.902 and 0.455, respectively, for identifying two groups. Conclusion: The changes of the CBF, FA, and DC(avg) values and their relative values can be applied to differentially diagnose patients with hyper-acute and acute cerebral infarction, which could provide the basis for selecting more reasonable treatment protocols.