Ischemia in the territory of a hypoplastic vertebrobasilar system

BACKGROUND: Congenital variations in the configuration and size of the cerebral vessels may predispose to ischemic stroke. OBJECTIVES/METHODS: To illustrate that a hypoplastic basilar artery may lead to posterior circulation ischemia in adults, eight cases are reported from two university medical centers. RESULTS: Five men and three women with a mean age of 49.8 years are reported. Four of the patients had other conventional stroke risk factors. Two patients had brainstem strokes, and six had TIA. All patients had hypoplastic basilar arteries. Seven patients had at least one hypoplastic vertebral artery (bilateral in five cases), and six patients had both posterior cerebral arteries originating from the internal carotid arteries. CONCLUSIONS: A hypoplastic basilar artery is frequently accompanied by vertebral artery hypoplasia, and this can predispose adults to posterior circulation ischemia. This entity can be suspected on the basis of MR angiogram, but conventional angiography will provide definitive diagnosis. Optimal medical and surgical treatment of this condition is unresolved.     

The mechanism of ischemic stroke in patients with dolichoectatic basilar artery

Basilar artery dolichoectesia (BD) may cause brainstem ischemia by multiple mechanisms, including thrombosis, embolism, occlusion of deep penetrating arteries. The objective of this study was to determine and characterize clinical, imaging findings and hemodynamic mechanisms in patients with cerebrovascular event associated with BD and compare these data with those for patients with BD who did not have stroke. We studied 29 consecutive stroke, two transient ischemic attack (TIA) patients with BD who have been admitted to our stroke unit. We sought the diameter of ectasia, height of the bifurcation, lateral displacement, shape deformities, and blood flow velocity of the basilar artery (BA) by transcranial Doppler. Imaging and hemodynamic findings were compared with those found in a group of 18 patients without stroke or TIA. The main infarct localization was pons, eight (28%) with restricted single lesion, 10 (32%) with multiple lesions involving thalamus, midbrain, posterior cerebral artery (PCA) territory. Patients with BD were more probably to have had stroke fitting a clinical and imaging patterns of multiple infarcts than those with restricted infarct in territories supplied by branches of the BA (60% vs. 40%). Hypertension and atherosclerotic changes of the posterior circulation were more frequent in patients with stroke than those without (P = 0.004 and P = 0.028, respectively), whilst the incidence of other vascular risk factors were not significantly different in two groups. Patients with stroke/TIA had more often low blood flow velocity but not significant in the BA when compared with those for BD patients without cerebrovascular event (71% vs. 39%; P = 0.1). Reduced blood flow velocity in the BA was correlated significantly with distal lesions involving thalamus, midbrain and PCA territory rather than those located in the territory supplied by branches of the BA (P = 0.02). In conclusion, it seems probably that BD may cause vertebrobasilar system ischemia by multiple mechanisms, especially reduced blood flow in the BA and atheromatous changes in the vertebrobasilar system may precipitate thromboembolic stroke.     

非心源性缺血性卒中复发危险因素分析

目的 分析非心源性缺血性卒中患者1年复发的危险因素。 方法 连续入选1978例发病7 d内的非心源性缺血性卒中患者。收集患者的人口学信息、血管病危险 因素和发病时的主要症状及体征,评价患者的头颅磁共振成像结果,包括梗死灶的部位、数量、急 性梗死灶的分布特征及责任动脉、责任动脉有无严重狭窄、缺血性卒中的病因分型。随访患者1年内 有无缺血性卒中或短暂性脑缺血发作（transient ischemic attack,TIA）的复发,通过多元Cox回归分析缺 血性卒中患者复发的危险因素。 结果 95例(4.8%)患者1年内缺血性卒中或TIA复发。冠状动脉粥样硬化性心脏病病史、缺血性卒中病 史、缺血性卒中发病前3个月内反复TIA、责任脑动脉狭窄程度≥70%和后循环缺血性卒中是1年内复发 的危险因素。 结论 后循环梗死、有责任脑动脉严重狭窄及缺血性心脑血管病病史的非心源性缺血性卒中患者复 发的风险较高。     

Association between vertebrobasilar artery geometry and vertebrobasilar stenosis,recurrence, and death in posterior circulation stroke and transient ischemic attack

BackgroundIntracranial atherosclerosis is one of the primary causes of posterior circulation stroke and transient ischemic attack (TIA), particularly in people of South and East Asian heritage. Focal vessel geometry may play a role in atherosclerosis progression. Thus, we investigated the relevance of vertebrobasilar artery (VBA) geometry and vertebrobasilar atherosclerotic stenosis, recurrence, and death in posterior circulation stroke and TIA.MethodsFour hundred and twenty patients with posterior circulation ischemic stroke or TIA were included. The VBA geometric features, comprising the geometric configurations (Tuning fork, Walking, Lambda, and No confluence), vascular bends (multi-bending and oligo-bending), and VBA stenosis degrees, were defined based on computed tomography angiography (CTA) images. Recurrence of stroke or TIA and death were assessed through a 1-year follow-up. Additionally, the relationship between VBA geometric features, VBA stenosis, and prognosis were analyzed.ResultsWalking type and vascular multi-bending showed significant associations with more severe VBA stenosis and distribution, and these were also more frequently observed in patients with large-artery atherosclerosis (LAA) stroke (all P < 0.05). Sixty-four patients exhibited recurrent stroke or TIA, and 31 died during the 1-year follow-up. In the binary logistic regression analysis, Walking type (P = 0.018), Lambda type (P = 0.021), and multi-bending type (P = 0.004) were found to be independently associated with stroke recurrence, while No confluence type was independently associated with death (P = 0.010).ConclusionsThe geometric characteristics of the VBA are associated with vertebrobasilar stenosis, LAA stroke, 1-year recurrence, and death in posterior circulation stroke and TIA. VBA geometry may be used to stratify the risk of stroke and TIA in the posterior circulation.     

Toward a further elucidation: role of vertebral artery hypoplasia in acute ischemic stroke

BACKGROUND AND PURPOSE: Congenital vertebral artery (VA) hypoplasia is an uncommon embryonic variation of posterior circulation. The frequency of this congenital variation was reported to be 2-6% from autopsy and angiograms. The aim of our study was to elucidate the role of VA hypoplasia in acute ischemic stroke. METHOD: We examined 191 acute ischemic stroke patients (age 55.8 +/- 14.0 years). TOAST subtypes were determined. A cervical magnetic resonance angiogram was performed in every patient. A duplex study of bilateral VA with flow velocities and vessel diameter recording in the intertransverse (V2) segment was performed within 72 h after onset of ischemic stroke. The net VA flow volume was measured in each subject. RESULT: The overall incidence of a unilateral congenital hypoplastic VA was 11.51%, which was statistically higher especially in cases of brainstem/cerebellar infarction. Of these, subjects with VA hypoplasia had an etiological preponderance of the 'large-artery atherosclerosis' subtype and a topographic preponderance of ipsilateral posterior circulation infarction. CONCLUSIONS: Based on our results, VA hypoplasia seemed a contributing factor of acute ischemic stroke, especially in posterior circulation territories.     

Pure midbrain ischemia and hypoplastic vertebrobasilar circulation

Isolated midbrain infarction is rare and little is known about etiology and patient’s long-term follow up. We aimed to describe the clinical features, the causative diseases and the outcome of patients with isolated midbrain infarction who were admitted to our center, focusing on vascular abnormalities of posterior circulation. All patients with first acute ischemic stroke limited to the midbrain were included and their demographic features, neurological symptoms, neuroimaging data, and cardiovascular risk factors were recorded. Functional outcome, using modified Rankin scale, was assessed at discharge and at the 3 month follow up evaluation. We found nine patients with acute isolated midbrain infarction, representing 0.61 % of all ischemic stroke admitted to our center. The most common cause of stroke was small-vessel disease (88.8 %). At stroke onset, none of the patients had consciousness disturbances, and four patients (44.4 %) had gait impairment, five patients (55.5 %) presented with diplopia due to involvement of the third nerve or fascicular type of third-nerve palsy, seven patients (77.7 %) had vascular anomalies of vertebrobasilar circulation: the most frequent was vertebral artery hypoplasia [four patients (44.4 %)]. At follow up evaluation, seven patients (77.7 %) had a good functional outcome and no patients experienced recurrence of cerebrovascular events. As isolated midbrain infarction is uncommon, specific ocular motor signs, mainly third-nerve palsy, may help to identify and localize the mesencephalic infarct. Abnormalities in vertebrobasilar circulation, such as hypoplastic basilar or vertebral artery, are frequently associated with isolated midbrain ischemia. The hypoplastic vertebrobasilar system may predispose to posterior ischemic stroke.     

Dissection of the Extracranial Vertebral Artery: Clinical Findings and Early Noninvasive Diagnosis in 24 Patients

Dissection of cervical arteries causes ischemic stroke in young adults. This reports the clinical, ultrasonographic, and neuroradiological findings in 24 patients with 28 vertebral artery dissections in the neck (4 occurring bilaterally). In 20 patients (83%), the dissection was temporally related to trauma. No patients had an underlying vascular disease, for example, atherosclerosis or fibromuscular dysplasia. In all, the major initial manifestation was pain in the occipital or neck region. The next most common symptoms were vertigo and nausea (in 17 patients). Clinical manifestations were vertebrobasilar transient ischemic attack (TIA) (5 patients: in 2 patients vestibulocerebellar TIA, in 1 patient visual TIA, in 1 patient motor TIA, and in 1 patient brain stem TIA with perioral paresthesia), cerebellar infarction (10 patients, in 4 patients bilateral), brainstem infarction (5 patients), posterior cerebral artery territory infarction (1 patient), and multiple vertebrobasilar ischemic lesions (3 patients). Typical angiographic findings were irregular narrowing of the vessel lumen or a tapering stenosis with distal occlusion. Magnetic resonance imaging showed a thickened vessel wall with hematoma signal at the site of the dissection. Duplex color-flow imaging was valuable for the early diagnosis of extracranial vertebral artery dissection and for follow-up examinations. The distal V1- and the proximal V2-segment (at the level of C6 vertebra) was the most frequent localization of dissections (in 43%). The outcome was favorable except for 2 patients with basilar artery occlusion. Embolism to the basilar artery may be avoided by early administration of anticoagulants.     

Acute Ischemic Stroke Involving Both Anterior and Posterior Circulation Treated by Endovascular Revascularization for Acute Basilar Artery Occlusion via Persistent Primitive Trigeminal Artery

We report a case of acute ischemic stroke involving both the anterior and posterior circulation associated with a persistent primitive trigeminal artery (PPTA), treated by endovascular revascularization for acute basilar artery (BA) occlusion via the PPTA. An otherwise healthy 67-year-old man experienced sudden loss of consciousness and quadriplegia. Magnetic resonance imaging showed an extensive acute infarction in the right cerebral hemisphere, and magnetic resonance angiography showed occlusion of the right middle cerebral artery (MCA) and BA. Because the volume of infarction in the territory of the right MCA was extensive, we judged the use of intravenous tissue plasminogen activator to be contraindicated. Cerebral angiography revealed hypoplasia of both vertebral arteries and the presence of a PPTA from the right internal carotid artery. A microcatheter was introduced into the BA via the PPTA and revascularization was successfully performed using a Merci Retriever with adjuvant low-dose intraarterial urokinase. After treatment, his consciousness level and right motor weakness improved. Although persistent carotid-vertebrobasilar anastomoses such as a PPTA are relatively rare vascular anomalies, if the persistent primitive artery is present, it can be an access route for mechanical thrombectomy for acute ischemic stroke.     

Basilar and distal vertebral artery stenosis: long-term follow-up

Forty-four patients with greater than or equal to 50% stenosis of a distal vertebral artery (VA) and/or basilar artery (BA) were followed up for an average of 6.1 years. Angiography was performed for definite vertebrobasilar (VB) transient ischemic attacks (TIA) in 19 (43%), for VB infarcts in 13 (30%) and for non localizing symptoms in 12 (27%). Stenosis in the BA with or without VA involvement was present in 28 patients (64%), while 16 patients (36%) had occlusive disease in one or both distal VA sparing the BA. In follow up, 7 patients (16%) had definite VB TIA and 3 patients had possible VB TIA. Eight patients (18%) sustained a stroke, 5 of which were in the VB territory. The observed stroke rate was 17 times the expected rate for a matched normal population. Eight patients died during follow up, three patients due to stroke (2 brainstem infarctions, one intraventricular hemorrhage). The observed 5 year survival rate was 78% compared to 90% in a matched normal population. In comparing this data with our previous study of 93 patients with proximal VA occlusive disease, distal VB occlusive disease appears to carry a higher risk for brainstem ischemia.     

Mechanisms of Stroke in Patients with Fetal Posterior Cerebral Artery

ObjectivesThe fetal-type posterior cerebral artery (FTP) is a normal variation of the posterior cerebral artery (PCA), occurring in 3–36% of general population. The effects of the FTP in stroke mechanisms remain debatable. We aimed to investigate the differences in stroke mechanisms and lesion locations between patients with and without FTP.MethodsA total of 394 patients with PCA territory stroke were divided into those with PCA ischemic stroke associated with ipsilateral FTP and those without. The baseline characteristics, vascular risk factors, infarct pattern, stroke location, stroke etiology, and the diameter of P1 in patients without FTP or posterior communicating artery (PcoA) in patients with FTP were investigated.ResultsAmong the 394 patients, 52 (13.2%) PCA stroke patients with ipsilateral FTP were enrolled. Patients with FTP, in comparison with those without, had a higher frequency of deep infarct pattern (69.2% vs. 47.1%, P=0.012), small vessel occlusion (51.9% vs. 28.9%, P=0.009), ventrolateral thalamic involvement (65.4% vs. 49.1%, P=0.042), and a lower frequency of cardiac embolism (9.6% vs. 24.0%, P=0.009). The diameter of P1 in patients without FTP was larger than that of PcoA in patients with FTP (2.1 ± 0.3 mm vs. 1.6 ± 0.2 mm, P <0.001).ConclusionsThe stroke mechanisms, infarct pattern, and the location of the stroke were different between patients with and without FTP. PCA stroke patients with FTP more often had small vessel occlusion and ventrolateral thalamic involvement. These results are probably associated with difference in the hemodynamic status according to the presence of FTP.     

Basilar artery occlusive disease in the New England Medical Center Posterior Circulation Registry

BACKGROUND: Most reports on basilar artery (BA) occlusive disease have retrospectively described single cases or small patient series. OBJECTIVE: To assess clinical and vascular features, stroke mechanisms, etiologies, and outcome of moderate to severe BA occlusive disease among 407 patients in the New England Medical Center Posterior Circulation Registry, the largest prospective series of consecutively collected patients with posterior circulation ischemia to date. RESULTS: We studied 87 patients and identified 3 patient groups with distinct vascular, clinical, etiological, and prognostic characteristics: isolated BA disease (39 patients [44.8%]), BA involvement as part of widespread posterior circulation atherosclerosis (36 patients [41.4%]), and embolism to the BA (12 patients [13.8%]). Vascular risk factors were common and often multiple. Most patients (54 [62.1%]) had involvement of the midportion of the BA. Fifty-eight patients (66%) initially had transient ischemic attacks, of whom 34 (58.6%) progressed to stroke. Transient ischemic attacks were usually multiple, lasted for several months, and increased in frequency as the stroke approached. When an infarct was present, the middle posterior intracranial territory was most often involved (66 patients [75.9%]). Outcome was much better than previously assumed. The mortality rate was 2.3%, and 62 patients (almost 75%) had minor or no deficits at follow-up. Outcome was best among patients with widespread atherosclerotic disease and worst in 7; (58.3%, with major disability) of 12 patients with embolism to the BA. Distal territory involvement, embolism, BA occlusion, decreased level of consciousness, tetraparesis, and abnormal pupils were significant predictors of poor outcome. CONCLUSION: Inclusion of patients into 1 of the BA groups and early identification of predictive outcome factors guide diagnostic evaluation and treatment.     

Distribution of artificial cerebral microemboli in stroke patients with patent foramen ovale

OBJECTIVES: Patent foramen ovale (PFO) is considered as an important risk factor for cerebrovascular diseases. Nevertheless, the relationship between the distribution of high-intensity transient signals (HITS), resulting from injection of air mixed with saline and detected by transcranial Doppler (TCD), and clinical cerebrovascular syndromes in these patients has not been investigated. METHODS: Using TCD, we screened 40 patients with stroke or transient ischemic attack (TIA), in whom PFO was proven by transesophageal echocariography (TEE). Of these, 30 patients (75%) with artificially produced HITS either in the middle cerebral artery (MCA) or the basilar artery (BA) were included in the analysis. RESULTS: Nineteen patients had a stroke or TIA in the carotid territory and 11 patients in the vertebro-basilar territory. HITS were found in the MCA in all 30 patients and in 21 of the 30 patients in the BA. Of the latter, ten patients were in the carotid group and 11 patients were in the veretebro-basilar group, p = 0.011. CONCLUSION: There is a significant association between the distribution of artificial HITS and the clinical cerebrovascular syndromes.     

椎动脉发育不全与卒中

目的 先天的椎动脉发育不全是一种后循环罕见的胚胎变异。从尸体解剖和血管造影中发现这种先天变异的频率为2%～6%。此研究的目的是阐明椎动脉发育不全在急性脑梗死中的作用。方法 我们收集了195位急性脑梗死患者(年龄57±13岁),并对每位受试者进行脑梗死类型（TOAST分型）的分类及磁共振血管造影（Magnetic Resonance Angiography,MRA）,并于卒中后72h内完成颈动脉超声及椎动脉血流量测量。结果 单侧的先天椎动脉发育不全总的发生率是11.79%;脑干、小脑梗死患者中发生率特别高。先天椎动脉发育不全与TOAST分类“大动脉粥样硬化”子类型相关。结论 基于我们的结果,先天椎动脉发育不全,特别在后循环上的先天椎动脉发育不全似乎是一种脑梗死的加重因素。     

Complete nonvisualization of basilar artery on MR angiography in patients with vertebrobasilar ischemic stroke: favorable outcome factors

BACKGROUND: In vertebrobasilar ischemic stroke, magnetic resonance angiography (MRA) occasionally fails to visualize the basilar artery, but in these patients, little attention has been given to establishing correlations between the clinical and the radiological findings. Our aim was to identify clinical or radiological measures that could assist in predicting a favorable clinical outcome. METHODS: Risk factors, clinicoradiological features, and functional outcomes were assessed in 40 patients with vertebrobasilar ischemic stroke whose basilar arteries were absent on MRA. The presence of potential feeding arteries to the posterior circulation was recorded from a review of the MRA data. To permit quantitative analysis of the images, a potential feeding artery score (PFAS; range: 0-8) was established. One point was assigned when a signal was seen from an intracranial vertebral artery, a posterior inferior cerebellar artery, a superior cerebellar artery, or a posterior cerebral artery. On MRI, the location of the infarction was classified as involving the proximal, middle, and distal territories of the intracranial posterior circulation. The infarctions were also categorized as single- or multi-sector infarctions, and according to whether more than one penetrating or branch artery was involved. Clinical outcomes were classified as favorable (modified Rankin Scale = 0-2) or poor (modified Rankin Scale = 3-6). RESULTS: The clinical outcome was favorable in 30% (n = 12) of patients, and poor in 70% (n = 28). A transient ischemic attack preceded the stroke in 48% of patients, especially those with a favorable outcome (67%). Patients with a favorable outcome had a higher PFAS (p = 0.036) and an increased incidence of single-sector infarction (p = 0.049). CONCLUSIONS: Our study suggests that a higher PFAS, accompanied by a single-sector infarction, is a predictor of improved clinical outcome in patients with vertebrobasilar ischemic stroke in which the basilar artery was absent on MRA.     

Neuroborreliosis-associated cerebral vasculitis: long-term outcome and health-related quality of life

Neuroborreliosis affects the nervous system after systemic infection with the spirochete Borrelia burgdorferi. Previously, cerebral vasculitis has been regarded as an extremely rare complication of neuroborreliosis. The data on the long-term outcome in patients with cerebral vasculitis due to neuroborreliosis are limited. The objective of this study was to perform a longitudinal analysis of cases of neuroborreliosis-associated cerebral vasculitis. We recruited all patients (n = 11) diagnosed with neuroborreliosis-associated in three neurological departments in an East German region. Inclusion criteria were sudden neurological deficits, magnetic resonance (MR) imaging findings that conform to cerebral ischemia or brain infarction, intrathecal synthesis of borrelia-specific antibodies, and non-atherosclerotic pathology of brain supplying arteries. Vasculitic changes were detected by digital subtraction angiography, MR angiography and/or transcranial Doppler ultrasound. Outcomes were measured by the modified Rankin scale (mRS) and EuroQoL Index. Cerebral vasculitis is a rare complication of Lyme disease (0.3 % of all cases in the endemic area). Ten out of 11 patients diagnosed with neuroborreliosis-associated vasculitis cerebral vasculitis using clinical, radiological and immunological criteria developed ischemic stroke or transient ischemic attacks (TIA), 7 patients had recurrent stroke. Vasculitic alterations could be demonstrated in 8 patients that all except one developed ischemic lesions. The median mRS was 3 (range 0–4) at admission and 2 (range 0–6) at discharge. The posterior circulation was affected in 8 of 11 patients; thrombosis of the basilar artery was detected in 2 patients, one died in the acute stage. Neuroborreliosis can cause recurrent stroke or TIA on the basis of cerebral vasculitis. Lumbar puncture is needed for detection of this potentially life-threatening condition. Early recognition and adequate therapy would possibly improve outcome.     

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。     

The fetal variant of the circle of Willis and its influence on the cerebral collateral circulation

In a fetal-type posterior circle of Willis (FTP) there is an embryonic derivation of the posterior cerebral artery (PCA) from the internal carotid artery (ICA). Besides the fact that a larger area is thus dependent on the ICA, leptomeningeal vessels cannot develop between the anterior and posterior circulation. The tentorium namely prevents cerebellar vessels from connecting to the PCA territory. Therefore patients with an FTP could be more prone to develop vascular insufficiency. An overview of the literature is given. We propose to define a partial FTP, in which a small P1 segment between the basilar artery and the postcommunicating part of the PCA is present, and a full FTP, in which the P1 segment is absent. Whether a full FTP is a risk factor for stroke should be subject of further investigation.     

Combined thrombolysis in posterior circulation stroke caused by bilateral vertebral artery dissection in squash player

Background and purposeGrowing number of vertebral artery dissection has been detected due to higher awareness and improved imaging techniques, even after seemingly minor head turning in young- or middle-aged adults without predisposing risk factors for cerebrovascular disease. Treatment options for this condition at this time are limited and there is a troubling shortage of controlled studies.Summary of caseOur patient suffered a bilateral vertebral artery dissection complicated by posterior circulation stroke. We decided to treat acute stroke with intravenous thrombolytic therapy. Patient's condition worsened despite the treatment so emergency angiography was performed to assess the arterial patency. Additional dose of recombinant tissue plasminogen activator together with mechanical thrombectomy was administered using intraarterial route. The patient recovered well and at 12-month follow-up visit he had only right marginal incomplete hemianopia.ConclusionsVertebral artery dissection should be taken into consideration in differential diagnosis of posterior circulation stroke or TIA in young patients with a history of even as subtle precipitating events as forceful head movements. Combined thrombolytic therapy may provide safe and effective treatment of stroke-complicated cases. This case report shows that expanded diagnostic protocol for acute ischemic stroke, including computed tomography perfusion study and angiography of cervical and cranial vessels, assures rapid and correct diagnosis.     

Vertebral artery stump syndrome in acute ischemic stroke

Although the carotid artery stump as an embolic source for ischemic stroke has been well described, there have been few systematic reports of a similar syndrome in the posterior circulation (PC) after vertebral artery (VA) origin occlusion. The aim of this study was to identify the incidence and characteristics of acute ischemic stroke with VA stump syndrome. Of 3463 consecutive patients who were admitted within 7 days after onset, 865 patients with acute ischemic stroke in the PC were enrolled. The diagnostic criteria of VA stump syndrome included: (1) acute ischemic stroke in the posterior circulation; (2) the VA origin occlusion identified on MRA, duplex ultrasound, CT angiography, and/or conventional angiography; (3) presence of distal antegrade flow in the ipsilateral VA; and (4) absence of other causes of ischemic stroke. Of the 865 patients with PC stroke, 12 (1.4%) were diagnosed as having VA stump syndrome. The ischemic lesions included the cerebellum in all patients. Nine patients had multiple ischemic lesions in the brain stem, thalamus, or posterior lobe other than cerebellum. On duplex ultrasound, a to-and-fro flow pattern was observed in the culprit VA in 10 patients. Three patients had recurrences of ischemic stroke in the PC during the acute phase. VA stump syndrome was not a rare mechanism of PC stroke, and there was a high rate of stroke recurrence during the acute phase. Vascular assessment by a multimodality approach can be used to promptly detect VA stump syndrome.     

Migraine and vertebrobasilar ischemia.

I studied 9 patients with migraine and posterior circulation ischemia. Inclusion criteria were (1) brainstem or cerebellar infarcts or transient ischemic attacks, (2) satisfactory vertebrobasilar angiograms, and (3) migraine. Excluded were patients with only occipital lobe ischemia, known arteriosclerosis, or other nonmigrainous vascular disease. Two women and 7 men, ages 6 to 58 years (mean, 34.7), had transient attacks only (2), single strokes (4), single stroke followed by attacks (1), or multiple strokes (2). Five had antecedent classic, 2 common migraine, and classic migraine began only after the initial ischemic event in the other two. The 7 stroke patients all had CT- or MRI-documented brainstem (4) or cerebellar (6) infarcts. Angiography was normal (3) or demonstrated basilar artery (BA) narrowing (2) or occlusion (4), or branch occlusion (1). In 3 patients the initially occluded BA later reopened. At follow-up (average 4.3 years, range 1 to 9 years), 5 were normal and 4 had important clinical deficits. I conclude that (1) "basilar migraine" is not always benign; it affects both sexes and a wide age range; (2) the pattern of headaches, attacks, and strokes varies; (3) migraine may appear only after ischemia; (4) some patients have BA occlusion or diffuse narrowing; and (5) BA occlusion can be temporary.