A subtle connection between crossed cerebellar diaschisis and supratentorial collateral circulation in subacute and chronic ischemic stroke.

Objectives: It has not been reported whether collateral circulation, a factor closely related to the prognosis of patients with cerebral infarction, is related to the occurrence of crossed cerebellar diaschisis(CCD) or not. Our research attempts to verify the relationship between the collateral circulation grade and the occurrence of CCD, mainly by means of CTA and CTP.

Materials And Methods: A total of 47 patients were divided into a CCD-positive (Kim et al., 2019) or a CCD-negative group Furlanis et al. (2018) by calculating the asymmetry index (AI) value (<10%) of bilateral cerebellar cerebral blood flow (CBF). A 4-scale grading method was used to evaluate collateral circulation in the supratentorial infarct area, and the four perfusion parameters of the supratentorial and subtentorial brain regions were analyzed and compared between the two groups. The extent of vascular lesions was evaluated by MR sequences including DWI and MRA.

Results: Among the four perfusion parameters, except for CBV, were significantly different between the bilateral cerebellum in the CCD-positive group, but only TTP in the supratentorial cerebral infarction area was statistically different in the two groups. Moreover, the collateral circulation sore in the CCD-positive group was significantly lower than that in the CCD-negative group. But no statistical difference was found in the comparison of DWI positive rates between the two groups.

Conclusion: The collateral score in the supratentorial infarct area is correlated with the occurrence of CCD,which may be used to explain the effect of CCD on the prognosis of patients.