Diagnostic Value Of Transcranial Doppler In Diagnosis Of Middle Cerebral Artery Stenosis Or Occlusion

Objectives:To assess the value of transcranial Doppler in diagnosing middle cerebral artery stenosis or occlusion and explore the optimal velocity values in diagnosing the degree of middle cerebral artery(MCA)stenosis by transcranial Doppler(TCD).Methods:We retrospectively recruited patients who had undergone TCD and DSA of the intracranial arteries in First Hospital of Jilin University from May 2013 to October 2016.The patients with internal carotid artery stenosis>50% diagnosed by DSA were excluded.The degree of middle cerebral artery stenosis was classified into five groups: normal,mild,moderate,severe and occlusion.We recorded peak systolic velocity(PSV),end-diastolic velocity(EDV),mean flow velocity(MFV),pulsitility index(PI)and the TCD spectrum of each MCA.Kruskal-Wallis test and was used to evaluate the difference among groups.The consistency of MCA stenosis or occlusion diagnosed by TCD and DSA was calculated with Kappa number.The optimal velocity values for diagnosing different degrees of MCA stenosis were determined by the receiver operating characteristic curve(ROC curve).Results:Among 381 patients,there were 319 males and 62 female and the average age was 56.6±12.5 years.Of the 762 MCA,the normal,mild,moderate,severe and occlusion were 530,48,45,75,and 64,respectively.There was significant difference in blood flow velocities among the five groups(P<0.001,respectively).Taking the DSA as the gold standard,Kappa value of TCD in diagnosing MCA stenosis or occlusion was 0.839.The specificity,sensitivity,coincidence rate of TCD in diagnosing MCA stenosis or occlusion were 90.1%,94.3%,91.5%.The optimal velocity values for normal and stenosis were: PSV=171cm/s(area under the curve 0.907,sensitivity 86.9%,specificity 93.0%,accuracy 92.1%,positive predictive value 74.6%,negative predictive value 94.9%),EDV=73cm/s(0.899,83.3%,92.6%,90.4%,62.4%,94.7%),MFV=103cm/s(0.906,86.3%,92.6%,90.9%,73.2%,94.2%);for mild and moderate were: PSV=191cm/s(0.853,91.1%,84.7%,85.5%,75.7%,97.0%),EDV=90cm/s(0.841,84.4%,81.2%,82.5%,65.6%,97.3%),MFV=124cm/s(0.851,86.7%,85.8%,84.5%,75.3%,97.5%);for moderate and severe were: PSV=240cm/s(0.876,81.3%,93.9%,94.9%,84.1%,97.2%),EDV=110cm/s(0.870,77.0%,95.7%,94.0%,79.7%,97.6),MFV=153cm/s(0.880,80.0%,96.5%,94.3%,81.5%,97.3%).In moderate and severe stenosis arteries,the abnormal TCD spectrum were common,such as pathological vortex,turbulence or unclear upper boundary etc.Conclusions:TCD is quite consistent with DSA in evaluating MCA stenosis or occlusion,and has high specificity,sensitivity,coincidence rate in estimating MCA stenosis or occlusion.Using PSV,EDV,MFV as the diagnostic criteria in diagnosis of MCA stenosis,the accuracies were all high,and PSV criteria had the highest accuracy.