Study The Diagnostic Value Of Middle Cerebral Artery Stenosis By Transcranial Doppler

Objective:Intracranial artery occlusive disease including middle cerebral artery and extracranial carotid artery occlusive disease are major causes of ischemic stroke. The purpose of the study was to evaluate the efficacy of Transcranial Doppler(TCD) of Middle cerebral artery (MCA)stenosis in comparison with magnetic resonance angiography (MRA).Methods: Part 1:There were 32 patients with MCA stenosis and 80 healthy adults in control group.All of them were underment examination of Transcranial Doppler. Part 2: we diagnosed 32 MCA stenosis patients using EME TC8080 TCD by a single reseach technician.All patients were given a MRA within 10 day after TCD examination.The severity of MCA stenosis was classified as normal-mild ,moderate and severe-void on the basis of the amount of signal loss and the lumen reduction of MCA in MRA. peak systolic velocity were observed.According to the different systolic velocities as following >130cm/s, >140cm/s, >150cm/s, >160cm/s, >170cm/s, we dromn different ROC(receiver operator characteristic curves )and determined which cutoff point was the best for diagnosing the MCA stenosis.Results: 1 In the case group,the number of vessel of peak systolic velocity under 140cm/s were 24, their mean MCA velocities were 101. 17 ±21. 86cm/s.23 (95. 83%) of vessel stand right triangle The window exist frequently, the acoustic frequency were clear and soft.1 (4. 17% )of vessel have change of the pathologic vortex.The number of vessel of Peak systolic velocity 140-180cm/s were 28, their mean MCA velocities were 157. 46±10. 22 cm/s and were faster than the control group (P<0. 05). 17(60. 71%)of vessel had change of the pathologic vortex with low noise (P<0.05),4(14.28%)of vessel had change of the pathology vortex with high noise, 1(3. 57%) of vessel present lines of forms of Doppler signals with noises of machinery. The number of vessel of Peak systolic velocity under 140-180cm/s were 12, their mean MCA velocities were 210. 33 ± 20. 38 cm/s,peak systolic velocity of them were faster than the control group(P<0.05),8(66.67%)of vessel had change of the pathologic vortex with low noise,2(16. 67%)of vessel had change of the trbulance with high noise.2 There was a obvious difference of systolic velocity among these four groups.3 The number of vessel with mormal,moderate and severe stenosis were 27, 19, 18 respectively in MCA,their mean MCA velocities were 99 ± 41cm/s, 175 ± 27cm/s, 261 ± 64cm/s respectively in TCD,there was a obvious difference of systolic velocity among these three groups .4 Through calculating the biggest areas under ROC ,we concluded that the optimal values of systolic velocity for diagnosing MCA stenosis was 140cm/s(areas under ROC curve was 0. 068,P<0. 001 ),and according to this cutoff point, It is specificity and sensitivity in diagnosing MCA stenosis were 81. 48% and 91. 89%(P<0. 05).5 The accurate ratios in diagnosis of MCA stenosis were the...