Study of collateral flow on arterial spin labeling after middle cerebral artery stenosis / 实用放射学杂志

ABSTRACT

Objective To study the value of three-dimensional pseudo-continuous arterial spin labeling(3D pCASL) for estimating collateral flow after middle cerebral artery(MCA) stenosis.Methods 3D pCASL was performed in 28 cases of negative diffusion weighted imaging(DWI) patients with MCA stenosis for estimating collateral vessels formation.The post-labeling delay(PLD) of 3D pCASL was set to 1.5 s and 2.5 s.The cerebral blood flow (CBF) of 3D pCASL with two PLD was calculated by AW workstation respectively.Nineteen normal persons were regarded as the control group.The 95% confidence interval of the ratio of left/right side of CBF of control group was set as reference value.The characteristic of the ratio of stenosed/contralateral side of CBF was analyzed.The characteristics of collateral flow was investigated with digital subtraction angiography(DSA).Results Abnormal perfusion was found in 28 patiens.Two types of abnormal perfusion were found, including typeⅠ rCBF(PLD=1.5 s) decreased,rCBF(PLD=2.5 s) was normal (n=16);typeⅡrCBF(PLD=1.5 s) decreased,rCBF(PLD=2.5s) decreased (n=12).On brain DSA, abundant of collateral flow supply was found in 16 patients with typeⅠabnormal perfusion,whereas deficiency of collateral flow supply was found in 12 patients with typeⅡ.Conclusion 3D pCASL with two PLDs may provide important reference value for estimating collateral flow after middle cerebral artery stenosis.