Application of MR perfusion-weighted imaging in patients with unilateral ICA stenosis or occlusion

Objective To investigate the diagnostic value of MR perfusion-weighted imaging (PWI) in patients with unilateral ICA high-grade stenosis or occlusion. Methods PWI was performed on 62 patients with unilateral ICA high-grade stenosis or occlusion. The cerebral perfusion parameters such as relative cerebral blood flow(rCBF), relative cerebral blood volume(rCBV), relative mean transit time(rMTT) and time to peak(TTP) were calculated.Fourteen cases underwent surgery or interventional therapy.The results of PWI were compared between before and after therapy. Results The abnormal perfusion findings were depicted in 62 patients with ICA high-grade stenosis or occlusion. The abnormal findings of PWI were delayed TTP and rMTT,normal or slightly decreased rCBF,normal or slightly increased rCBV. The values of rCBV, rMTT and TTP had statistically significant difference(P0.01).Forty cases had involvement of middle cerebral artery territory and border zone on MTT and TTP maps. Twenty-two cases had invovlement of border zone on MTT and TTP maps.In 14 cases receiving therapy, the values and the extents of abnormal perfusion of TTP and rMTT were decreased (P0.01).Conclusion PWI can demonstrate the abnormal cerebral hemodynamic changes in patients with unilateral ICA high-grade stenosis or occlusion and provide valuable diagnostic and therapeutic information.