New England Medical Center Posterior Circulation registry

Among 407 New England Medical Center Posterior Circulation registry patients, 59% had strokes without transient ischemic attacks (TIAs), 24% had TIAs then strokes, and 16% had only TIAs. Embolism was the commonest stroke mechanism (40% of patients including 24% cardiac origin, 14% intraarterial, 2% cardiac and arterial sources). In 32% large artery occlusive lesions caused hemodynamic brain ischemia. Infarcts most often included the distal posterior circulation territory (rostral brainstem, superior cerebellum and occipital and temporal lobes); the proximal (medulla and posterior inferior cerebellum) and middle (pons and anterior inferior cerebellum) territories were equally involved. Severe occlusive lesions (>50% stenosis) involved more than one large artery in 148 patients; 134 had one artery site involved unilaterally or bilaterally. The commonest occlusive sites were: extracranial vertebral artery (52 patients, 15 bilateral) intracranial vertebral artery (40 patients, 12 bilateral), basilar artery (46 patients). Intraarterial embolism was the commonest mechanism of brain infarction in patients with vertebral artery occlusive disease. Thirty-day mortality was 3.6%. Embolic mechanism, distal territory location, and basilar artery occlusive disease carried the poorest prognosis. The best outcome was in patients who had multiple arterial occlusive sites; they had position-sensitive TIAs during months to years.     

New England Medical Center Posterior Circulation Stroke Registry II. Vascular Lesions

Among 407 New England Medical Center Posterior Circulation Registry (NEMC-PCR) patients, the extracranial (ECVA) and intracranial vertebral arteries (ICVA) were the commonest sites of severe occlusive disease followed by the basilar artery (BA). Severe occlusive lesions were found in >1 large artery in 148 patients; 134 had unilateral or bilateral severe disease at one arterial location. Single arterial site occlusive disease occurred most often in the ECVA (52 patients, 15 bilateral) followed by the ICVA (40 patients, 12 bilateral) and the BA (46 patients). Involvement of the ICVAs and the BA was very common and some patients also had ECVA lesions. Hypertension, smoking, and coronary and peripheral vascular disease were most prevalent in patients with extracranial disease while diabetes and hyperlipidemia were more common when occlusive lesions were only intracranial. Intra-arterial embolism was the most common mechanism of brain infarction in patients with ECVA and ICVA occlusive disease. ICVA occlusive lesions infrequently caused infarction limited to the proximal territory (medulla and posterior inferior cerebellum). BA lesions most often caused infarcts limited to the middle posterior circulation territory (pons and anterior inferior cerebellum). Posterior cerebral artery occlusive lesions were predominantly embolic. Penetrating artery disease caused mostly pontine and thalamic infarcts. Prognosis was poorest in patients with BA disease. The best prognosis surprisingly was in patients who had multiple arterial occlusive lesions; they often had position-sensitive transient ischemic attacks during months or years.     

多灶性后循环缺血患者的病灶分布与血管形态异常及近期预后分析

目的 观察多灶性后循环缺血患者的病灶分布和血管形态异常的特点,评估患者出院时的近期预后及其与病灶分布和血管形态的关系.方法 对34例经过MR/所证实的多灶性后循环缺血患者行主动脉弓及全脑血管DSA,全面分析病灶分布及血管形态异常的特点;同时对患者出院时的近期预后用改良Rankin分级(MRS)评分表进行评估,分析病灶分布及血管形态异常与近期预后的关系.结果 多灶性后循环缺血患者最常被累及的部位是脑桥(22例),最常被累及的区段是中段+远段(12例);34例患者中有26例(76.5%)DSA显示出血管形态异常,最常被累及的动脉是椎动脉起始段(14例)和颅内段(13例)及基底动脉(7例);出院时7例患者(20.6%)存在预后不良,其中6例(17.6%)为重度残疾,1例(2.9%)死亡.近中远段同时受累和基底动脉受累的患者表现出预后不良.结论 血管形态异常是多灶性后循环缺血的重要病理基础和致病因素,病灶区段的分布和数目及血管受累部位是决定预后的关键因素.     

Posterior cerebral artery territory infarcts in the New England Medical Center Posterior Circulation Registry.

BACKGROUND: Infarcts in the territory of the posterior cerebral arteries (PCAs) are common. Although associated clinical symptoms and signs are known, the mechanisms of stroke and the anatomical distribution of PCA territory lesions caused by the various stroke mechanisms are less well defined. Published reports have selected only special subgroups of patients. PATIENTS AND METHODS: We studied stroke mechanisms, infarct distribution, and clinical findings among 79 patients in the New England Medical Center Posterior Circulation Registry in whom brain imaging scans showed infarcts that involved 1 or more cortical territories of the PCA. RESULTS: Forty-eight patients (61%) had infarcts limited to the PCA territory (pure PCA), while 31 (39%) also had infarcts in other territories (PCA+). Infarcts were in the cortical territory of the PCA in 47 patients (59%) and were cortical and deep in 32 (41%). Infarcts that were cortical and deep were more common in PCA+ lesions. Stroke mechanisms were embolism of cardiac origin (32 [41%]), proximal arterial disease (25[32%]), cryptogenic embolism (8[10%]), intrinsic PCA disease (7[9%]), vasoconstriction (4[5%]), and coagulopathy (3[4%]). Patients with cardiogenic embolism and intrinsic PCA disease often had pure PCA territory infarcts, while patients with proximal arterial disease more often had PCA+ infarcts. Visual abnormalities were present in 66 patients (84%). Motor weakness, cognitive and behavioral abnormalities, and ataxia were found in 20 patients (25%); only 12 (15%) had sensory signs. CONCLUSIONS: The great majority of pure PCA and PCA+ territory infarcts are caused by cardiac or intra-arterial embolism. Intrinsic PCA disease, vasoconstriction, and coagulopathy are less common causes of infarction.     

Bilateral intracranial vertebral artery disease in the New England Medical Center, Posterior Circulation Registry.

BACKGROUND: Previous studies of patients with bilateral intracranial vertebral artery (ICVA) disease were selective and retrospective. METHODS: We studied risk factors, vascular lesions, symptoms, signs, and outcomes in patients with bilateral ICVA disease among 430 patients in the New England Medical Center Posterior Circulation Registry. RESULTS: Forty-two patients had bilateral ICVA occlusive disease (18 had bilateral stenosis; 16, unilateral occlusion and contralateral stenosis; and 8, bilateral occlusion). The most common risk factors were hypertension (32/42 [76%]) and hyperlipidemia (22/42 [52%]). Sixteen patients (38%) had transient ischemic attacks (TIAs) only; 18 (43%), TIAs before stroke. Occlusive vascular disease also involved the basilar artery in 29 patients (69%), the extracranial vertebral arteries in 18 (43%), and the internal carotid arteries in 11 (26%). Only 6 patients had no other major vascular lesion. Cerebellar symptoms were common. Among 30 patients with infarction, 21 (70%) had proximal intracranial territory involvement, and 15 (50%) had distal territory involvement. The location of occlusive lesions in relation to posterior inferior cerebellar artery origins did not significantly influence prognosis. During follow-up, 31 patients had no symptoms or slight disability, 2 had progression, and 7 died. Among 7 patients with poor outcome, 6 also had basilar artery stenosis or occlusion and 5 had proximal and distal intracranial territory infarcts. CONCLUSIONS: Most patients with bilateral ICVA occlusive disease have hypertension, other major occlusive lesions, and TIAs before stroke. Short- and long-term outcomes are usually favorable, but patients with bilateral ICVA and basilar artery-occlusive lesions often have poor outcomes.     

The intracranial vertebral artery: a neglected species. The Johann jacob wepfer award 2012

Among posterior circulation arteries, the intracranial vertebral artery (ICVA) has been given the least attention, especially concerning treatment of occlusive lesions. Early clinicopathological studies showed that the ICVA was often occluded in patients with lateral medullary and posterior inferior cerebellar infarcts. Severe stenosis or occlusion of the ICVA was the most common arterial lesion among the 408 patients in the New England Medical Center Posterior Circulation Registry (NEMC-PCR). In this registry, the distal portion of the artery was most often involved, sometimes with spread into the basilar artery. ICVA occlusive lesions were often bilateral and very often accompanied by basilar and cervical vertebral artery occlusive lesions. Patients with bilateral ICVA occlusions often had attacks of dizziness, blurred vision, and ataxia during months and years but rarely later developed disabling infarction. Most posterior circulation infarcts in patients with ICVA occlusive lesions were located in the middle and distal posterior circulation territories and were rostral to the medulla and inferior cerebellum. Although diagnostic techniques now image the ICVA and its lesions well, the optimal treatment of patients with various ICVA occlusive lesions has very rarely been analyzed or reported. The therapeutics of patients with ICVA disease is uncharted territory and begs for attention and clarification.     

Multiple large and small cerebellar infarcts

To assess the clinical, topographical, and aetiological features of multiple cerebellar infarcts,18 patients (16.5% of patients with cerebellar infarction) were collected from a prospective acute stroke registry, using a standard investigation protocol including MRI and magnetic resonance angiography. Infarcts in the posterior inferior cerebellar artery (PICA)+superior cerebellar artery (SCA) territory were most common (9/18; 50%), followed by PICA+anterior inferior cerebellar artery (AICA)+SCA territory infarcts (6/18; 33%). One patient had bilateral AICA infarcts. No infarct involved the PICA+AICA combined territory. Other infarcts in the posterior circulation were present in half of the patients and the clinical presentation largely depended on them. Large artery disease was the main aetiology. Our findings emphasised the common occurrence of very small multiple cerebellar infarcts (<2 cm diameter).These very small multiple cerebellar infarcts may occur with (13 patients/18; 72%) or without (3/18; 22%) territorial cerebellar infarcts. Unlike previous series, they could not all be considered junctional infarcts (between two main cerebellar artery territories: 51/91), but also small territorial infarcts (40/91). It is suggested that these very small territorial infarcts may be endzone infarcts, due to the involvement of small distal arterial branches. It is possible that some very small territorial infarcts may be due to a microembolic process, but this hypothesis needs pathological confirmation.     

Lesion patterns and etiology of ischemia in the anterior inferior cerebellar artery territory involvement: a clinical – diffusion weighted – MRI study

The topography and mechanism of stroke in the anterior inferior cerebellar artery (AICA) territory are delineated before, but the detailed clinical spectrum of lesions involving AICA territory was not studied by diffusion weighted imaging (DWI). We reviewed 1350 patients with posterior circulation ischemic stroke in our registry. We included patients if the diagnosis of AICA territory involvement was confirmed, and DWI, and magnetic resonance angiography were obtained in the 3 days of symptoms onset. The potential feeding arteries of the AICA territory were evaluated on magnetic resonance imaging (MRI) using a three-dimensional rotating cineoangiographic method. There were 23 consecutive patients with lesion involving AICA territory, six with isolated lesion in the AICA territory, six with posterior inferior cerebellar artery, 11 with multiple posterior circulation infarcts (MPCIs). The clinical feature of isolated AICA infarct was vertigo, tinnitus, dysmetria, ataxia, facial weakness, facial sensory deficits, lateral gaze palsy, and sensory-motor deficits in patients with pontine involvement. Patients with largest lesion extending to the anterior and inferolateral cerebellum showed mixed symptomatology of the lateral medullary (Wallenberg's syndrome) and AICA territory involvement. Patients with MPCIs presented various clinical pictures with consciousness disturbances and diverse clinical signs because of involvement of different anatomical structures. Large-artery atherosclerotic disease in the vertebrobasilar system was the main cause of stroke in 12 (52%) patients, cardioembolism (CE) in one (4%), and coexisting large-artery disease and a source of CE in four (17%). The main cause of stroke was atheromatous vertebrobasilar artery disease either in the distal vertebral or proximal basilar artery. The outcome was usually good except those with multiple lesions. The new MRI techniques and clinical correlations allow better definition of the diverse topographical and etiological spectrum of AICA territory involvement and associated infarcts which was previously based on pathological and conventional MRI studies.     

Embolism from vertebral artery origin occlusive disease.

We report 10 patients with severe occlusive disease of the vertebral artery (VA) origin in the neck with intra-arterial embolism to the posterior circulation. The VA lesions in seven patients were complete occlusions, and three patients had severe atherostenosis. All patients had strokes in the vertebrobasilar territory. The most frequent recipient sites of intra-arterial embolism were the intracranial VA-posterior inferior cerebellar artery region (8), and the distal basilar artery (BA) and its superior cerebellar and posterior cerebral artery branches (7). Two patients had pontine infarction due to BA embolism. The most common clinical signs were due to cerebellar infarction. Atherosclerotic disease of the VA origin has features in common with disease of the internal carotid artery origin. Both have similar risk factors and demography, and each can cause strokes by intracranial intra-arterial embolism.     

Basilar artery stenosis: middle and distal segments

We report the clinical features and prognosis in nine patients with angiographically documented basilar artery stenosis of the middle and distal segments. Six patients had transient ischemic attacks (TIAs), and in two this was their only clinical manifestation. The TIAs in four patients included two or more of the following symptoms: dizziness, diplopia, perioral numbness, dysphagia, weakness, or loss of consciousness. Two other patients had isolated symptoms of transient dizziness and unilateral weakness. Seven patients had posterior circulation strokes, preceded by TIAs in four. Basilar artery occlusive disease can affect any segment of the artery. The short-term prognosis of middle and distal basilar artery stenosis was good especially when patients were treated with warfarin or platelet antiaggregants.     

Multiple acute infarcts in the posterior circulation.

OBJECTIVE--to evaluate clinical, radiological, and prognostic features of patients with multiple acute infarcts in remote arterial territories of the posterior circulation. DESIGN--Data analysis from a prospective acute stroke registry in a community based primary care centre using a standard protocol including MRI and MRA. RESULTS--In three and a half years, 27 of the 236 patients (11%) with posterior circulation stroke had multiple acute infarcts in the posterior circulation as shown by gadolinium enhancement on MRI. Eighteen patients had multiple infratentorial and supratentorial infarcts including the cerebellum and posterior cerebral artery territory, with coexisting brainstem involvement in seven patients. Fourteen patients had a rostral basilar artery syndrome and cerebellar signs; four patients had a visual field defect with cerebellar signs. Causes were vertebral (six) or basilar (four) artery atheromatosis, and cardioembolism (four). Seven patients had multiple acute infarcts in the posterior circulation of the cerebellum and lower brainstem. Brainstem and cerebellar signs were found in most patients (five); aetiologies were small vessel disease (four), cardioembolism (one), and vertebral artery dissection (one). Two patients with large artery atheromatosis had multiple acute infarcts in the posterior circulation in the brainstem and posterior cerebral artery territory. One month after stroke more than 25% of the patients were dependent or had died. There was no difference in the outcome between the three groups, and recovery was linked to the size of infarcts rather than to a high number of infarcts. CONCLUSIONS--multiple acute infarcts in the posterior circulation usually involve the cerebellum. Simultaneous brainstem and posterior cerebral artery territory infarcts sparing the cerebellum are uncommon. They can be suspected clinically before neuroimaging, mainly when supratentorial and infratentorial infarcts coexist. This may be important, because different patterns of infarction are associated with different causes of stroke.     

青年与中老年患者颅内大动脉粥样硬化性缺血性卒中影像学特点比较研究

目的 基于DWI 影像对比青年和中老年大动脉粥样硬化性缺血性卒中（i schemi c stroke,I S）患者病变 分布特征的差异。 方法 回顾性分析伴有颅内大动脉粥样硬化性狭窄/闭塞的IS患者颅脑DWI上IS病变的影像学数据。 基于DWI上梗死灶分布特征,将病变分为单发、单区域多发和多区域多发IS病变,同时评估累及前后循 环的情况。患者分为青年组（18～50岁）和中老年组（51～80岁）。比较两组患者的病灶数目及位置分 布特征差异。应用单因素和多因素logistic回归分析年龄组与IS病变分布特征的相关性。 结果 共纳入146例患者,其中青年组69例（47.3%）,平均年龄40.5±8.4岁,男性54例（78.3%）;中 老年组77例（52.7%）,平均年龄62.4±7.1岁,男性42例（54.5%）。两组在病灶数目及分布特征上有 差异（P =0.033）,青年患者主要表现为多区域多发病变（50.7%）,中老年患者主要表现为单区域多发 病变（37.7%）。单因素l ogi sti c回归分析显示,青年组相比于中老年组更易发生多区域多发I S病变（OR 2.72,95%CI 1.17～6.29,P =0.020）,校正临床混杂因素（高血压史、降压药及他汀的使用情况）和 颅内动脉狭窄率后,两组多区域多发IS病变发生率差异仍具有统计学意义（OR 2.73,95%CI 1.04～7.12, P =0.041）。在前、后循环病变分布特征上,两组未见明显差异,青年和中老年组均以单纯前循环病变 为主（69.6% vs 75.3%）,且单纯前循环病变以皮层下分布为主（56.2% vs 55.2%）;在单纯后循环病 变,两组均最常见脑干受累（81.2% vs 89.5%）。 结论 对于伴有症状性颅内大动脉粥样硬化性狭窄/闭塞的IS患者,青年患者较中老年患者更容易发 生多区域多发性梗死。两组人群均最常见单纯前循环供血域受累,且以皮层下分布为主;在单纯后循 环病变,以脑干受累为主。     

Recent Advances in Cerebellar Ischemic Stroke Syndromes Causing Vertigo and Hearing Loss

Cerebellar ischemic stroke is one of the common causes of vascular vertigo. It usually accompanies other neurological symptoms or signs, but a small infarct in the cerebellum can present with vertigo without other localizing symptoms. Approximately 11 % of the patients with isolated cerebellar infarction simulated acute peripheral vestibulopathy, and most patients had an infarct in the territory of the medial branch of the posterior inferior cerebellar artery (PICA). A head impulse test can differentiate acute isolated vertigo associated with PICA territory cerebellar infarction from more benign disorders involving the inner ear. Acute hearing loss (AHL) of a vascular cause is mostly associated with cerebellar infarction in the territory of the anterior inferior cerebellar artery (AICA), but PICA territory cerebellar infarction rarely causes AHL. To date, at least eight subgroups of AICA territory infarction have been identified according to the pattern of neurotological presentations, among which the most common pattern of audiovestibular dysfunction is the combined loss of auditory and vestibular functions. Sometimes acute isolated audiovestibular loss can be the initial symptom of impending posterior circulation ischemic stroke (particularly within the territory of the AICA). Audiovestibular loss from cerebellar infarction has a good long-term outcome than previously thought. Approximately half of patients with superior cerebellar artery territory (SCA) cerebellar infarction experienced true vertigo, suggesting that the vertigo and nystagmus in the SCA territory cerebellar infarctions are more common than previously thought. In this article, recent findings on clinical features of vertigo and hearing loss from cerebellar ischemic stroke syndrome are summarized.     

Stroke in patients with migraine

Background and purposeMigraine with aura (MA) is considered as a risk factor for ischaemic stroke. The present observational retrospective study compares migraine patients admitted for a documented stroke with those presenting focal neurological symptoms and headache without a demonstrable lesion and in which the final diagnosis was a migraine attack with aura.Material and methodsThe study included 14 migraine patients with a stroke and 37 without a stroke. The clinical characteristics, the vascular risk factors and the results of the technical examinations were compared.ResultsStroke occurred in migraine patients with aura as well as without aura. Classical vascular risk factors were rather rare. Patent foramen ovale (PFO) with or without atrial septum aneurysm appeared to be the main risk factor for stroke in patients with a history of migraine. Infarcts were mainly located in the supratentorial territory of the posterior cerebral circulation. Also some lobar haematomas were observed, but their aetiology remained uncertain. The strokes were generally mildly severe with good outcome. Hyperintense signals in the cerebral white matter and cerebellum, on T₂-weighted magnetic resonance imaging, were more frequent in the migraine patients with stroke.ConclusionsThe presence of PFO, rather than of MA, appeared to be the main risk factor for stroke patients with migraine. No direct relation between migraine and stroke could be demonstrated.     

Posterior circulation ischemic stroke in Korean population

To understand the characteristics of posterior circulation ischemic stroke (PCS) in the Korean population better, we retrospectively reviewed the data from the Hallym Stroke Registry (HSR). We analyzed the demographic features, risk factors, stroke subtypes, lesion distributions and clinical outcomes of 591 consecutive patients with PCS, enrolled in HSR between January 1996 and July 2002. PCS was 39.8% of all ischemic strokes. Mean age of PCS patients was 63.4 years and 55.7% were men. Hypertension was the most common risk factor (69.9%). However, potential cardioembolic sources were found only in 11.0%. The most frequent stroke subtype was large artery disease (50.0%), followed by small vessel disease (33.8%). Only 5.2% of patients were classified as affected with cardioembolism. The most common location of infarcts was in the middle territory (36.5%), followed by distal (28.1%), proximal (19.0%), and multiple territories (16.4%). The hospital mortality rate (4.1%) and discharge outcome of PCS were comparable with those of the anterior circulation stroke (ACS). In conclusion, the etiology and lesion topography of PCS in the Korean population appeared to be different from those of the Caucasians.     

加强对后循环缺血性卒中/短暂性脑缺血发作的认识

后循环缺血性卒中（posterior circulation stroke,PCS）/短暂性脑缺血发作（transient ischemic attack,TIA）占全部卒中及TIA的1/5,其临床表现按血管分布可呈现不同的症状,以头晕最常 见。50%以上椎-基底动脉梗死患者在几天或几周前会出现TIA症状,这些先兆症状可辅助早期识别 PCS。PCS的复发率高于前循环,尤其是伴椎-基底动脉狭窄的患者,可通过完善计算机断层扫描血管 成像（computed tomography angiography,CTA）、磁共振血管成像（magnetic resonance angiography,MRA） 等辅助检查明确血管狭窄程度。另外,对侧支循环建立充分的后循环重度狭窄或闭塞,其神经功能 缺损程度较轻,且预后更好。     

Midbrain infarction: associations and aetiologies in the New England Medical Center Posterior Circulation Registry

Most reports of midbrain infarction have describedclinicoanatomical correlations rather than associations andaetiologies. Thirty nine patients with midbrain infarction (9.4%) aredescribed out of a series of 415 patients with vertebrobasilarischaemic lesions in the New England Medical Center PosteriorCirculation Registry. Patients were categorised according to therostral-caudal extent of infarction. The "proximal" vertebrobasilarterritory includes the medulla and posterior inferior cerebellar artery territory. The "middle" territory includes the pons and anterior inferior cerebellar artery territory. The "distal" territoryincludes the rostral midbrain, thalami, superior cerebellum, and medial temporal and occipital lobes. Midbrain infarction was accompanied by"proximal" territory infarcts in four patients, and by "middle" territory infarction in 19 patients. Thirteen patients had associated "distal" territory infarcts, three of whom had occipital ortemporal lobe infarcts. Only three patients had isolated midbraininfarcts. Cardioembolism (n=11), in situ thrombosis (n=9), large artery to artery embolism (n=7), and intrinsic branch penetrator disease (n=5)were the most common aetiologies. Bilateral infarction and accompanyingpontine infarction were associated with the most extensivevertebrobasilar occlusive disease. Midbrain infarction was 10-fold morelikely to be accompanied by ischaemia of neighbouring structures thanit was to occur in isolation. Recognition of the different patterns ofinfarction may act as a guide to the underlying aetiology and vascular lesions.

     

Cardiac sources of embolism and cerebral infarction--clinical consequences and vascular concomitants: the Lausanne Stroke Registry

We studied clinical characteristics and coexisting causes of stroke in 305 patients admitted to a population-based primary care center with an initial ischemic stroke and a potential cardiac source of embolism (PCSE). Using systematic standardized cardiac, arterial, and cerebral investigations and the logistics of the prospective Lausanne Stroke Registry, we found that nonprogressive onset, hemianopia without hemiparesis or hemisensory disturbances, Wernicke's aphasia, ideomotor apraxia, involvement of specific territories (posterior division of middle cerebral artery, anterior cerebral artery, cerebellum, multiple territories), and a hemorrhagic component were associated with the presence of a PCSE, as compared with 1,006 initial ischemic stroke patients without PCSE. Although age and sex did not differ, the frequency of hypertension, diabetes, cigarette smoking, elevated blood cholesterol, and deep hemispheric or brainstem infarcts was higher in the patients without a PCSE. Nearly one-fourth of the patients with a PCSE had a coexisting potential arterial cause of stroke (large artery greater than or equal to 50% stenosis or small-vessel disease). In the majority of patients with a PCSE (76.7%), cardioembolism was the most likely cause of stroke, although a direct source of embolism was uncommon (4.3%) and intracranial embolic occlusions were present in less than one-half of the patients who were angiographed.     

Coronary Artery Bypass Grafting-Associated Ischemic Stroke; A Clinical and Neuroradiological Study

Ischemic stroke occurring after coronary artery bypass grafting (CABG) has been attributed to various factors. Little is known about the perioperative course and radiological topography of CABG-associated strokes. In this study the clinical and computed tomography features of 25 patients with ischemic stroke following coronary artery bypass grafting were evaluated. Four patients awakened with focal signs, and 21 developed an ischemic stroke 1 to 22 days after surgery. All 4 patients with early stroke had prolonged episodes of operative hypotension. Three of these patients had multiple subcortical and cortical infarcts. Of the 21 patients with late-onset ischemic stroke, 19 had single-territory infarcts (middle cerebral artery territory, N = 12; posterior cerebral artery territory, N = 4; anterior cerebral artery territory, N = 3). Two patients had multiple territory infarcts in the anterior and posterior circulation. No watershed infarcts were found in any of the 25 patients. New-onset atrial fibrillation and location of ischemic stroke in a single vascular territory were more common in patients who had an ischemic stroke after an asymptomatic interval. Duplex sonographic findings of the carotid arteries and oculoplethysmography (OPG) were available for 13 patients. Only 1 patient had an ipsilateral carotid stenosis. Of 21 patients who underwent postoperative two-dimensional echocardiography (with additional transesophageal echocardiography in 4), 2 had a left ventricular thrombus. These findings support the concept that post-CABG stroke is likely embolic.     

小脑梗死的分型与后循环血管病变

目的 研究有无大血管病变患者小脑梗死灶的特征,探讨小脑梗死分型与后循环血管病变的关系。 方法 收集我科自2006年1月～2008年3月期间住院的小脑梗死患者共35例,所有患者均同时具备颅脑磁共振成像（magnetic resonance imaging,MRI）和血管造影检查,包括计算机断层摄影血管造影（computed tomographic angiography,CTA）、磁共振血管造影（magnetic resonance angiography,MRA）和数字减影血管造影（digital subtraction angiography,DSA）检查。根据血管造影检查的结果将入组患者分为两组：大血管病变组20例,小血管病变组15例,分析两组小脑梗死的分型和后循环血管病变（包括狭窄或闭塞）的关系。 结果 ⑴大血管病变组20例中,颅内血管（椎动脉颅内段或基底动脉）病变最多见（10例,50%）,梗死类型多为分水岭梗死（7例,70%）;其次为颅外血管合并颅内血管（椎动脉颅外段合并颅内段或基底动脉）病变（8例,40%）,梗死灶多为小脑后下动脉（PICA）供血区的区域性梗死（7例,87.5%）;单独颅外血管（椎动脉颅外段）病变最少见（2例,10%）,梗死分布无明显倾向性。⑵小血管病变组15例中,梗死灶亦多位于分水岭区（9例,60%）。 结论 由于小脑血液供应特点,小脑梗死中分水岭梗死和腔隙性梗死较区域性梗死更为常见。小梗死灶（直径≤2cm）可能存在后循环大血管的狭窄或闭塞,应予积极的治疗和干预,以防病情加重。