Cerebral cortical microinfarcts in patients with internal carotid artery occlusion

Cerebral cortical microinfarcts (CMI) are small ischemic lesions that are associated with cognitive impairment and probably have multiple etiologies. Cerebral hypoperfusion has been proposed as a causal factor. We studied CMI in patients with internal carotid artery (ICA) occlusion, as a model for cerebral hemodynamic compromise. We included 95 patients with a complete ICA occlusion (age 66.2 ± 8.3, 22% female) and 125 reference participants (age 65.5 ± 7.4, 47% female). Participants underwent clinical, neuropsychological, and 3 T brain MRI assessment. CMI were more common in patients with an ICA occlusion (54%, median 2, range 1–33) than in the reference group (6%, median 0; range 1–7; OR 14.3; 95% CI 6.2–33.1; p<.001). CMI were more common ipsilateral to the occlusion than in the contralateral hemisphere (median 2 and 0 respectively; p<.001). In patients with CMI compared to patients without CMI, the number of additional occluded or stenosed cervical arteries was higher (p=.038), and cerebral blood flow was lower (B −6.2 ml/min/100 ml; 95% CI −12.0:–0.41; p=.036). In conclusion, CMI are common in patients with an ICA occlusion, particularly in the hemisphere of the occluded ICA. CMI burden was related to the severity of cervical arterial compromise, supporting a role of hemodynamics in CMI etiology.     

颈内和大脑中动脉狭窄与闭塞的梗死类型及卒中机制的研究

目的 研究单侧动脉粥样硬化性MCA/ICA狭窄与闭塞的急性缺血性脑卒中患者在DWI上的梗死类型及发病机制.方法 起病48h内DWI诊断的急性脑梗死伴有动脉粥样硬化性MCA/ICA狭窄与闭塞的131例患者,有潜在心源性栓子患者除外.急性期DWI上梗死病灶分为：（1）单发病灶（小的穿动脉梗死灶;大的穿动脉梗死灶,皮层支梗死,大面积梗死,分水岭梗死）;（2）多发梗死病灶.结果 131例患者,ICA51例,MCA80例.ICA出现最多的梗死类型：穿支动脉伴分水岭梗死,但与MCA比较,皮层支伴分水岭梗死具有统计学意义（8/51,P=0.001）.MCA以穿支动脉伴皮层支梗死最多,且与ICA比较,具有统计学意义（12/80,P=0.003）.MCA中任何皮层支梗死与狭窄程度无关,ICA中任何分水岭梗死与狭窄程度相关.结论 颈内和大脑中动脉狭窄与闭塞在DWI上的梗死类型有明显的不同,提示有着不同的卒中发病机制.     

Predictive factors of outcome and stroke recurrence in patients with unilateral atherosclerosis-related internal carotid artery occlusion

Background: Clinical outcome of internal carotid artery (ICA) occlusion is highly variable and the reason is uncertain. Aim: To study the predictive factors of clinical outcome and stroke recurrence in patients with ischemic stroke associated with unilateral atherosclerosis-related ICA occlusion. Settings and Design: Prospective study in neurology department of a single hospital. Materials and Methods: We prospectively studied 66 patients who suffered from first-ever ischemic stroke associated with unilateral atherosclerosis-related ICA occlusion over a period of two years. The end point was death or stroke recurrence. Statistical Analysis: Chi-square or Fisher's exact test was used to analyze predictors of early functional outcome. Multivariate analysis was used to analyze predictors of death or stroke recurrence within two years. Result: Higher age ((3)70 years) predicted a worse functional outcome ( P = 0.049). Total anterior circulation syndrome (TACS) was associated with a poor functional outcome ( P P = 0.001). Stroke in evolution predicted a poor outcome ( P = 0.001), while those with symptom improvement had a better outcome ( P = 0.016). Pneumonia predicted a poor outcome ( P = 0.021). Five patients expired and 22 patients suffered from recurrent stroke in the following 24 months. Previous transient ischemic attack (TIA) and anemia were associated with a higher risk of death or recurrent stroke within two years ( P = 0.036, P = 0.012). Conclusion: High age, TACS, stroke in evolution and pneumonia were predictors for poor functional outcome. Previous TIA and anemia were predictors for death and recurrent stroke within two years.     

Free radical scavenger, edaravone, in stroke with internal carotid artery occlusion

BACKGROUND: Edaravone has potent free radical quenching and antioxidant actions. The agent has been recently in commercial use for acute ischemic stroke patients. In this study, we investigated the therapeutic effect of edaravone on severe carotid-territorial stroke. METHODS: Stroke patients with internal carotid artery occlusion and baseline NIH Stroke Scale Score > or =15 were treated for 14 days with drip intravenous infusion of edaravone (n=30) and were compared with a historical control cohort of similar patients (n=31). Glycerol was also administered to all patients in both groups. RESULTS: Infarct volume (P<0.02) and midline shift (P<0.02) on CT performed on day 2 of the patients treated with edaravone were smaller than those without edaravone. For patients with edaravone, infarct volume (P<0.0001) and midline shift (P<0.0001) on days 5-7 were greater than those on day 2. Hemorrhagic transformation of infarcts on day 2 was less severe in patients with than without edaravone (P<0.03). Within 14 days after the onset of stroke, 6 patients with edaravone (20%) and 14 without edaravone (45%) died directly of stroke (P<0.03). Among all patients, only two treated with edaravone were independent without any assistance 8 weeks after the onset. CONCLUSIONS: Edaravone was associated with delayed evolution of infarcts and edema in patients with severe carotid-territorial stroke and decreased mortality during the acute stage. The agent, however, failed to prevent evolution of infarcts and edema on later days, and did not significantly improve functional outcome among the surviving patients.     

Transient ocular motor paresis associated with acute internal carotid artery occlusion

While sudden monocular blindness and occlusion of the central retinal artery associated with acute thrombosis of the internal carotid artery are well reported, concurrent unilateral ophthalmoparesis is not. We studied 3 adult men who did not have other major signs of vascular disease but who exhibited the complete syndrome. The initial paresis of the oculomotor, trochlear, and abducens nerves varied in each individual and slowly cleared over days to weeks in all, but vision did not return in any. Each had mild-to-moderate signs of hemispheric dysfunction. In each, the thrombus extended from the origin of the internal carotid to its intracranial bifurcation into the anterior and middle cerebral arteries. It also occluded the proximal one-half to two-thirds of the ophthalmic artery. None had evidence of vasculitis or compromise of the posterior circulation.     

External carotid artery stenting in symptomatic internal carotid artery occlusion

We report the case of a patient with an anterior ischemic stroke due to tandem occlusion of the left M2 segment and ipsilateral internal carotid artery (ICA), with concomitant severe stenosis of the ipsilateral external carotid artery (ECA) and contralateral ICA, and moderate stenosis of the left vertebral artery (VA); as thrombectomy was not possible, stenting of the right ICA was performed. Two days after significant recovery, the patient showed neurological deterioration when in upright position, and brain magnetic resonance imaging confirmed decreased cerebral blood flow on the left hemisphere. Stenting of the left ECA and balloon angioplasty of the ipsilateral VA were performed in order to increase collateral flow, with an almost complete resolution of symptoms. This case highlights the importance of assessing the collateralization pattern when an ICA occlusion is present, and the potential need to revascularize an ipsilateral stenotic ECA.     

Clinical implications of collateral middle cerebral artery flow in acute ischaemic stroke with internal carotid artery occlusion

Background and purpose: The presence of collateral middle cerebral artery (MCA) flow via the primary collateral pathway is thought to protect against the progression of cerebral ischaemia. However, there have been few reports on early clinical outcomes according to the presence of collateral MCA flow in acute ischaemic stroke (AIS) with internal carotid artery (ICA) occlusion. Therefore, we sought to investigate the early clinical outcomes and lesion patterns according to the presence of collateral MCA flows in AIS with ICA occlusion. Methods: This is a retrospective study of patients with AIS with ICA occlusion consecutively admitted to our stroke center between October 2008 and March 2010. Patients were included if they were admitted within 12 h of symptom onset with AIS and symptomatic ICA occlusion. Collateral MCA flow was defined as the presence of MCA signals from proximal M1 to distal MCA branches ipsilateral to the ICA occlusion by magnetic resonance angiography. Early neurological deterioration (END) was defined as a 4‐point increase in the National Institutes of Health Stroke Scale (NIHSS) score and persistent neurological deterioration for at least 24 h or newly developed neurological symptoms within 7 days. Results: Sixty‐five patients (42 men, 23 women) were finally included. Initial NIHSS scores were significantly lower, and favorable outcomes at 3 months were better in patients with collateral MCA flow than in those without (P < 0.001). Initial lesion patterns were different according to the collateral MCA flow. However, patients with mild AIS might more frequently deteriorate than those with moderate to severe AIS. Conclusions: In our study, collateral MCA flow reduced initial stroke severity and was associated with favorable outcomes at 3 months but did not seem to protect against END in mild AIS patients with ICA occlusion. Therefore, the results of this study suggest that mild AIS patients with ICA occlusion should be carefully managed because their conditions may deteriorate.     

Markers of lacunar stroke in patients with moderate internal carotid artery stenosis

The benefits of surgical correction of moderate internal carotid artery stenosis have been demonstrated only in symptomatic subjects. It is debatable whether patients with lacunar infarct ipsilateral to a moderate carotid stenosis may be considered symptomatic like those with large–artery stroke. The aim of the study was to seek markers capable of differentiating patients with lacunar or non–lacunar stroke ipsilateral to a moderate internal carotid artery stenosis.We enrolled 95 patients with a first stroke ipsilateral to a moderate (50–69 %) stenosis of the internal carotid artery and divided them into lacunar and non–lacunar stroke based on clinical presentation and neuroradiological findings; 34 subjects with asymptomatic moderate carotid stenosis and 31 normal individuals were also studied. Baseline characteristics; risk factors, cerebrovascular reactivity to hypercapnia evaluated by means of the breath–holding index (BHI), the presence and severity of carotid stenosis and intimamedia thickness (IMT) of the common carotid arteries were determined. There were 36 patients with lacunar and 59 with non–lacunar stroke. Degree of stenosis, and IMT and BHI ipsilateral to symptomatic stenosis were found to be significant independent predictors as each 10 % increase of stenosis carried a 4.3 higher probability of non–lacunar stroke (95 % CI: 1.91–9.51); each decimillimeter increment in IMT increased this probability by 1.45 (95 % CI: 1.10–1.92); and the risk odds ratio associated with each 0.1 increase in BHI was 1.88 (95 % CI: 1.33–2.66). A decrease in BHI of 0.1 thus carried a 90% greater probability of having a lacunar stroke. The results show that patients with moderate internal carotid artery stenosis and lacunar stroke can be differentiated from those with non–lacunar stroke on the basis of distinctive ultrasonographic findings. Further studies are needed to clarify whether our findings have pathogenetic implications and may be of help for the planning of different therapeutic strategies in patients with moderate internal carotid stenosis and lacunar or non–lacunar ipsilateral stroke.     

Spontaneous bilateral internal carotid artery dissection with acute stroke in young patients

We studied the clinical and neuroradiological features of 41 cases with spontaneous bilateral internal carotid artery dissection (ICAD), including 3 cases in our hospital and 38 retrieved from the English literature. Bilateral ICAD accounts for 15.8% of young stroke patients with ICAD in our hospital. The most common presentations are head and/or neck pain, cerebral ischemia, carotid bruit and Horner's syndrome. The cerebral ischemic symptoms are extremely variable in bilateral ICAD, including unilateral hemisphere, bilateral hemisphere or brainstem-like symptoms. Although the underlying pathogenesis remains uncertain, good vascular and clinical outcomes are achieved for spontaneous bilateral ICAD.