A Clinical Study Of Acute Lacunar Infarction By TCD And Monitor Microemboli In Cerebral Circulation

Objective:The purpose of this study aimed at evaluating the correlation between condition of cerebral arterial and lacunar cerebral infarction clinical feature,outcome risk factors and monitor microemboli in the acute lacunar infarction by transcranial Doppler(TCD),so we can reveal the etiology and pathogenesis of Lacunar infarction and have an assessment of cerebrovascular to make individualized therapeutic decision.Methods:TCD examination was performed on 240 consecutive patients presenting with first-ever lacunar infarcts confirmed by CT or/and MRI between August 2006 and August 2008.The clinical subgroup according to the result of TCD examinations were divided into 4 groups:the normal baseline TCD group;the intracranial artery stenosis group;the extracranial artery stenosis group;the combined intracranial and extracranial artery stenosis group.60 healthy controls were enrolled as control group.All these examinations were completed within 72 hours from stroke on-set.Severity of the neurological deficit was quantified with the use of National Institutes of Health Stroke Scale(NIHSS) at 1th and 14th day.Then we calculated the NIHSS and assessed the clinical outcomes.TCD were applied to monitor microemboli in cerebral circulation in all groups.All patients were treated according to stroke unit and recurrent vascular events of the ischemic cerebralvascular case were was prospectively evaluated after stroke onset at half of one year.Comparisons were done among all groups in rate of the ischemic cerebralvascular disease recurrence.NIHSS and microemboli detected.Resoult:Concerning the risk factor of lacunar infarcts.The frequency of hypertension.diabetes mellitus,smoking hyperlipidemia and cerebral artery stenosis in lacunar infarcts group were more frequent compared normal controls.The difference was significant(P＜0.05).whereas the variation was not significant in either Drinking or not(P＞0.05).Multiple logistic regression analysis revealed:hypertension(p＜0.05), smoking(p＜0.001),diabetes mellitus(p＜0.001),cerebral artery stenosis and hyperlipidemia (p=0.043) were independently associated with an increased risk of lacunar stroke. (Figure3)The incidence of intracranial and extracranial arterial stenosis in lacunar infarction group was 47.5%(114/240).Normal control group was 0.05%The difference between the two groups was significant.(p＜0.05).(Figure 2)MES positive rate of lacunar infarction patients without cranial artery stenosis was 1.7%(2/114),This was significantly lower than any of other three groups. Differences were significant(χ2=13.92,χ2=7.378,χ²=13.93;P＜0.05).But there were no significant different among lacunar infarction patients with cranial artery stenosis.(χ²=0.535,χ²=0.672,χ²=0.028,P＞0.05)(Figure 5)10(45.5%) patients had further ischemic events in the MES positive group during 6 months follow-up.While in the MSE negative group,the recurrence rate of further ischemic events within 6 months was 17.45%。There was significantly different between the two groups(χ²=8.07,P=0.005)(Figure 6).Only 1 of the 60 reporting on recurrent stroke actually provided a definition of recurrent stroke in normal control group.The risk of recurrence among lacunar patients during the first half one year ranged from 7.1-41.3%,The recurrence risks of the intracranial artery stenosis group and the combined completed and extracranial artery stenosis group were higher than normal control group(P＜0.05),there was no statistically significant difference in the risk of recurrent stroke between normal control group versus non-cerebral artery stenosis lacunar patients(P＞0.05).The difference recurrence risks between the extracranial artery stenosis group and non- artery stenosis lacunar infarction groups were no significant(P＞0.05).(Figure 7).NIHSS scores between 1th day and 14^th day of non-cranial artery stenosis lacunar infarction,intracranial artery stenosis and and extracranial artery stenosis group were significant(t=-3.44,p＜0.01;t=4.36,p＜0.01;t=5.82,p＜0.01).Neurological improvement was statistically different between the two time point.As for the combined intracranial and extracranial artery stenosis group there was no statistically different in NIHSS scores between 1^thand 14^th day(t=2.82 P＞0.05).there was no significant neurological deficit improvement in this group.(Figure 8)Conclusion:1.Hypertension as well as diabetes,smoking.high uric acic and hyperlipidemia were important risk factors for patients with lacunar stroke.Patients presenting with lacunar stroke more often had cerebral artery stenosis.Cerebral artery stenosis may play an important role in the process of lacunar infarction.Something should be done to assess the condition of cerebral artery of lacunar cerebral infarction patients.2.Our data show that microembolic signals(MES) appears in appreciable proportions of lacunar infarction with cerebral artery stenosis.For these reasons,we conclude that MES plays a pathogenic role in lacunar infarction.It predicts further cerebral ischemia.and should be considered when therapeutic decisions are made.TCD examination should be considered as part of routine investigation and might identify a group of patients who are most likely to benefit from antithrombotic treatment.3 Lacunar cerebral infarction patients with intracranial or/and extracranial artery stenosis have a higher risk of ischemic cerebral infarction;Patients with combined intracranial and intracranial cerebral artery stenosis have worset clinical outcome and highest reoccur ischemic cerebral infarction.4 The present results indicate the usefulness of noninvasive assessment of hemodynamic parameter of cerebral arteries with TCD as a diagnostic tool that may help to identify different mechanisms of lacunar infarction.The noninvasive measurements may have predictive power with respect to lacunar infarction clinical outcome.