Extracranial surgery for vertebro-basilar ischaemia (experience of 8 cases).

Atheromatous lesions of the proximal vertebral artery and the subclavian artery may lead to ischaemic manifestations, occasionally with severe consequences in the vertebro-basilar territory. These transient ischaemic attacks are most often caused by haemodynamic insufficiency rather than thrombo-embolic complications addressed by anticoagulant and antiaggregant treatments. In this study, 8 cases of vertebro-basilar ischaemia (VBI), secondary to subclavian and proximal vertebral artery lesions, are reported. Surgical techniques, subclavian-to-subclavian artery by-pass (5 cases) and vertebral to common carotid artery transposition (3 cases) are described with their respective results. Through a review of the literature, the various operative modalities are discussed in the different pathological conditions of the proximal extracranial vertebro-basilar disease. It appears that the subclavian to subclavian artery by-pass as well as the vertebral-to-common carotid artery transposition are safe surgical procedures with strikingly low morbidity and mortality rates. The widely achieved relief of the ischaemic episodes, undoubtedly makes this surgery an alternative to medical treatment.     

Long term survival after basilar artery occlusion. 4 cases

Four cases of basilar artery occlusion with a follow-up from 7 to 12 years are reported. The first patient, a 60 year old woman, had a proximal occlusion which was revealed by an acute brain stem ischemia. The second case was a 63 year old man with an aortic aneurysm who had a single episode of vertebro-basilar insufficiency. Cerebral angiography demonstrated a lower basilar artery occlusion. The third patient, a 60 year-old woman, had been operated from right carotid artery and left vertebral artery stenosis; 8 years later, without clinical manifestations, a left carotid artery stenosis and an occlusion of the lower part of the basilar artery were discovered. The evolution was eventless after a left carotid endarterectomy. The last case was a 60 year old man who had a lower basilar artery occlusion associated with a left internal carotid occlusion. There was a full recovery after a hemiplegic stroke. From our personal cases and the review of the literature, long term survival after basilar artery occlusion may occur in occlusions restricted to the lower or middle part of the basilar artery and with a good collateral supply from carotid and cerebellar arteries.     

Les infarctus bulbaires: Etude des lésions vasculaires dans 26 observations

The pattern of arterial occlusion and related lesions have been studied in 26 cases with 38 medullary infarcts. In 10 of these cases, only the intracranial vessels were examined. In the 16 other cases, the entire cerebral arterial supply was dissected.Medial infarcts were more often related to occlusion of the vertebral artery involving the termination of the artery ($\text{7}\text{10}\text{cases}$). In 6 cases a thrombosis on an atheromatous plaque and, once, an embolus of cardiac origin, were found.Lateral infarcts were usually due either to occlusion of the vertebral artery ($\text{14}\text{23}\text{cases}$), reaching, in 10 cases, the mouth of the posterior inferior cerebellar artery (PICA) or to an isolated occlusion of the latter vessel (3 cases). A thrombosis on an atheromatous plaque was found in 15 cases, and emboli from the heart or from the origin of the vertebral artery in the others.The dorsal infarcts were related, in $\text{4}\text{5}\text{cases}$, to an isolated occlusion of the stem of the PICA and, in the other case, to one of the vertebral artery involving the ostium of the PICA. A thrombosis due to atheromatous stenosis was found in 4 cases, an embolus of cardiac origin in the other one.     

Vertebro-basilar ischaemia with thrombosis of the vertebral artery: report of two cases with embolism.

Two cases with vertebro-basilar infarcts associated with severe stenosis of the vertebral artery in its cervical part is reported. Complete thrombosis of the vertebral artery was observed after a short delay in both cases. As the carotid arteries were normal and the controlateral vertebral artery was dominant, an embolic mechanism was suspected. No new event occurred in the following one and three years respectively after the stroke. These two cases demonstrate the possibility of embolism from severe stenosis of the cervical vertebral artery. This mechanism could explain some of the infarcts related to vertebral artery occlusion.     

A young adult case of spontaneous basilar artery dissection]

We reported a case of basilar artery dissection in a 20-year-old man suffering sudden onset of consciousness disturbance. Brain CT revealed a cerebral infarction of the whole territories of vertebro-basilar artery and his 3DCT showed the occlusion at the base of basilar artery. Autopsy revealed that the subintimal dissection was found at the base of basilar artery and the dissection was spreaded to the distal of bilateral posterior cerebral arteries. The characteristics of his vertebro-basilar artery were small in diameter, thin media and thickened intima. According to these findings, we supposed this rare case of basilar dissection occurred all at once based on a functional abnormality in his small vertebro-basilar arterial wall.     

对颈动脉粥样硬化溃疡斑块内超声造影的定量研究

目的 了解颈动脉粥样硬化溃疡斑块内新生血管的血流动力学定量特点。方法 将颈动脉粥样硬化易损斑块患者按有无临床缺血症状分为症状组与非症状组,比较两组患者溃疡斑块发生率;对易损斑块进行超声造影检查,比较溃疡斑块和非溃疡斑块的造影剂到达时间、达峰时间、斑块内新生血管增强密度和斑块峰值强度/颈动脉管腔峰值强度比值差异。分析两组斑块血流动力学特点及斑块内新生血管的定量特征。结果 入组41例患者,共有48个易损斑块。症状组溃疡斑块发生率为68.2%,无症状组溃疡斑块发生率为38.5%,差异有统计学意义（P <0.05）。超声造影检查显示溃疡斑块组造影剂到达时间、斑块内新生血管增强密度和斑块峰值强度/颈动脉管腔峰值强度比值较非溃疡斑块组差异有统计学意义（7.21±2.17 s vs 10.32±3.17 s,P <0.05;15.1±6.4 dB vs 11.3±5.1 dB,P <0.05;0.64±0.17 vs 0.47±0.21,P <0.05)。结论 缺血症状组溃疡斑块的发生率较高;溃疡斑块组的新生血管密度高于非溃疡斑块组。     

The posterior inferior cerebellar artery arising from the internal carotid artery directly: a variant of the persistent primitive hypoglossal artery]

We reported a rare case of the posterior inferior cerebellar artery arising from the internal carotid artery directly. A 33-year-old male was admitted to our hospital with the complaint of throbbing type headache. CT showed no abnormal findings. A saccular aneurysm at the bifurcation of the left middle cerebral artery was revealed by MR angiography and the left internal carotid angiography. The right internal carotid angiography demonstrated an anomalous branch originating at the level of the C1/2 in the cervical portion of the internal carotid artery. This branch terminated as the posterior inferior cerebellar artery without an interposed segment of the vertebro-basilar artery. The ipsilateral vertebral artery was aplasia. T2-weighted MR image showed a flow-void penetrating the right hypoglossal canal. This vessel was confirmed an artery passing through the hypoglossal canal with the source images of the three-dimensional time-of-flight MR angiography. We diagnosed it as a kind of variant of the persistent primitive hypoglossal artery. The persistent primitive hypoglossal artery is composed of the proximal segment derived from the primitive hypoglossal artery, and the distal segment consisting of portions of the lateral anastomotic channels (primitive lateral basillo-vertebral anastomosis) which give rise to the posterior inferior cerebellar artery. We speculated that this variant resulted from the persistence of the proximal segment, which communicated with the stem of the posterior inferior cerebellar artery via the distal segment, and next, the disconnection of the posterior inferior cerebellar artery origin with the vertebral artery due to the aplasia of right vertebral artery and the involution of the distal segment connected to the basilar artery.     

Dissecting aneurysms of the posterior inferior cerebellar artery: report of four cases and review of the literature

Dissecting aneurysms frequently involve the vertebral arteries and their branches, but those exclusively on the posterior inferior cerebellar artery (PICA) represent only 24 cases in the literature, including the four cases discussed in this article. The clinical diagnosis lacks pathognomonic signs or symptoms, with presentations such as subarachnoid haemorrhage or ischaemia of the brain stem or the cerebellum, and the management is controversial. Wrapping, clipping and embolisation of the aneurysms were tried in this series with different outcomes. Exclusion of the pathological segment should be performed, as shown by rebleeding from our case which was wrapped or by progression of the vascular disease in cases where treatment was delayed. Surgical or endovascular occlusion are well tolerated in our cases and in those reported from the literature, which implies the absence of normal perforating branches to the brain stem arising from the proximal dissected segment of the PICA and a good collateral circulation. A revascularisation procedure using the occipital artery can be performed in order to prevent infarction if an endovascular test occlusion is not tolerated.     

Megadolichobasilar artery and acute cerebrovascular pathology

Sixteen patients with a megadolichobasilar artery and acute cerebrovascular symptoms are reported. All were explored by computerized tomography and vertebral angiography. Nine had transient ischaemic attacks or definitive ischaemic lesions, whereas 7 had subarachnoid or intracerebral haemorrhage. Among the patients with ischaemic troubles, vertebro-basilar insufficiency and pontine infarction were the most common clinico-radiological findings. Among the patients with intracranial haemorrhage, 4 had associated aneurysms or arteriovenous malformations, while 3 had subarachnoid or intracerebral haemorrhage with no vascular malformations on the angiograms. The possible relationships between the megadolichobasilar anomaly and the cerebral ischaemic or haemorrhagic pathologies are discussed also from a review of the pertinent literature.     

Megadolichobasilar artery and acute cerebrovascular pathology

Sixteen patients with a megadolichobasilar artery and acute cerebrovascular symptoms are reported. All were explored by computerized tomography and vertebral angiography. Nine had transient ischaemic attacks or definitive ischaemic lesions, whereas 7 had subarachnoid or intracerebral haemorrhage. Among the patients with ischaemic troubles, vertebro-basilar insufficiency and pontine infarction were the most common clinico-radiological findings. Among the patients with intracranial haemorrhage, 4 had associated aneurysms or arteriovenous malformations, while 3 had subarachnoid or intracerebral haemorrhage with no vascular malformations on the angiograms. The possible relationships between the megadolichobasilar anomaly and the cerebral ischaemic or haemorrhagic pathologies are discussed also from a review of the pertinent literature.     

Infarction of the medulla and cervical cord after fitness exercises

The clinical association of a left lateral medullary syndrome with left corticospinal and posterior column deficits is reported in the case of a young woman with a left vertebral artery dissection. The signs are explicable on the basis of occlusion of branches of the vertebral artery to both the upper cervical cord and the medulla. The dissection may have been due to sustained rotation of the neck during fitness classes. In view of the undocumented benefits and the potential unwanted effects of this exercise, it is doubtful whether it should be recommended.     

A Case of Wallenberg's Syndrome Presenting with Spontaneous Thrombosis of a Vertebral Artery Aneurysm

Complete spontaneous thrombosis of intracranial aneurysms is uncommon. Although this type of thrombosis is largely asymptomatic, in rare cases it can be accompanied by parent artery occlusion and ischemic stroke. There are limited reports of complete thrombosis of an unruptured aneurysm of the internal carotid artery and middle cerebral artery. Furthermore, there are no reports of occlusion of the vertebral artery caused by thrombosis of an aneurysm. The mechanisms of spontaneous thrombosis are not established. However, aneurysm morphology, arteriosclerosis, and stagnation of aneurysm flow have been suggested. Herein, we present a novel case of Wallenberg's syndrome caused by a fusiform aneurysm in which complete thrombosis of the proximal vertebral artery occurred. We discuss the mechanisms of thrombosis caused by an unruptured aneurysm, which may be useful for managing such patients who present with transient ischemic attacks.     

小脑后下动脉解剖变异致双侧小脑梗死2例报道并文献复习

目的 探讨小脑后下动脉(posterior inferior cerebellar artery, PICA)解剖变异致双侧小脑梗死的临床特征及发病机制。方法 对2例经颅脑MRI确诊的双侧小脑梗死患者采用CT血管造影(CTA)、磁共振血管成像(MRA)或数字减影血管造影(DSA)显示其头颈部血管,从而了解后循环血管的形态特征并复习相关文献。结果 病例1经DSA证实左侧椎动脉较细,远端管腔闭塞,通过右椎动脉代偿供血原左侧PICA供血区但欠充分,双侧PICA共同起源于右侧椎动脉。病例2经CTA证实右侧椎动脉较左侧明显细且远端显示欠清,MRA示双侧PICA共同起源于左侧椎动脉。结论 2例双侧小脑梗死患者均存在一侧椎动脉优势供血,且双侧PICA共同起源于该侧椎动脉。在该解剖变异基础上一侧椎动脉发生病变时可出现双侧小脑梗死。因此,在临床中出现双侧小脑梗死时临床医师不能忽略这一解剖变异基础。     

Recently occluded intracranial and extracranial carotid arteries. Relevance of the unstable atherosclerotic plaque.

BACKGROUND AND PURPOSE: It is now widely accepted that thrombotic coronary artery occlusion usually follows rupture of an unstable atherosclerotic plaque. The significance of such instability in arteries supplying the brain is less well appreciated. We therefore describe the clinical and pathological features of recent, symptomatic internal carotid artery occlusion to examine the pathogenetic role of plaque instability at both extracranial and intracranial sites. METHODS: Cases were selected from a consecutive series of 188 adult neuropathology autopsies. In 90 of these, the principal neuropathological abnormality was cerebral infarction, in 14 cases due to recent occlusion of 1 or more segments of the internal carotid artery. In each case, a full systemic, cardiovascular, and neuropathological autopsy was performed. Plaque instability was assessed by the presence or absence of a large, necrotic, lipid core; a thin, fibrous cap; and superficial inflammation. RESULTS: Of the 14 cases, 3 showed extracranial (carotid sinus), 7 intracranial, and 4 both extracranial and intracranial carotid artery occlusion. In 6 of the 7 occluded carotid sinuses, thrombus overlay an ulcerated, unstable, atherosclerotic plaque. In 1 extracranial and all 11 intracranial occlusions, there was either no atheroma or a mildly stenotic, stable, fibrous plaque, and in these cases, the cause of occlusion was embolism (8 cases), giant-cell arteritis (1 case), and unknown (3 cases). CONCLUSIONS: Coronary-type rupture of an unstable atherosclerotic plaque is the usual cause of fatal occlusion of the carotid sinus, but other causes usually underlie intracranial carotid occlusion. The nature and consequences of intracranial atherosclerosis require further study.     

A giant fusiform basilar aneurysm treated by bilateral vertebral artery occlusion.

OBJECTIVE AND IMPORTANCE: Fusiform aneurysms of the vertebrobasilar arteries that progressively enlarge causing symptomatic brainstem compression are dangerous and their treatment is difficult. A patient with such an aneurysm treated successfully with staged, microsurgical occlusions of the proximal vertebral arteries is described, and the literature pertaining to this rare condition is briefly reviewed. CLINICAL PRESENTATION: A 48-year-old man with a fusiform basilar trunk aneurysm of uncertain etiology presented initially with transient ischemic attacks (TIAs) of the posterior circulation that ceased with anticoagulation. Four years later he presented again with progressive ataxia, dysphagia and dysphonia due to considerable enlargement of the aneurysm causing brainstem compression. INTERVENTION: Staged microsurgical vertebral artery occlusions proximal to the aneurysm were performed. The second (left) vertebral artery was clipped only after the patient passed its temporary occlusion with an endovascular test balloon. The aneurysm subsequently thrombosed, the distal basilar artery kept patent by a single (left) posterior communicating artery. The patient's clinical condition improved markedly over a number of months as the aneurysm mass atrophied. CONCLUSION: Giant vertebrobasilar aneurysms are rare but treacherous lesions, sometimes justifying aggressive management. Carefully selected patients with progressive and severe symptoms due to brainstem compression may tolerate proximal vertebral artery occlusions, provided there is adequate collateral flow to the basilar termination and all of its perforating branches.     

Balloon Angioplasty of lntracranial Arteries for Stroke Prevention

Stroke from surgically inaccessible intracranial atherostenosis remains a formidable clinical challenge. While antithrombotic or antiplatelet therapy may prevent distal embolism, there is no effective program for plaque stabilization preventing progression of atherosclerotic stenosis. In patients with isolated circulations (single vertebral with absent posterior communicating arteries, single carotid with contralateral internal carotid artery occlusion, or single carotid with an absent anterior communicating artery), occlusion of the stenotic vessel may produce a low flow–mediated stroke. Fifteen patients with atherosclerotic intracranial stenoses were treated by balloon angioplasty after medical therapy with warfarin failed. Treated territories included the distal internal carotid, proximal middle cerebral, distal vertebral, and basilar arteries. Dilation was successful in all vessels, with residual stenoses averaging less than 30%. Two complications included one paramedian pontine stroke and a single vessel rupture that proved fatal. There was no recurrence of transient ischemic attacks and no restenosis at the angioplasty site over a follow–up period of more than 24 months. In this small series, balloon angioplasty of intracranial vessels provided a therapeutic option for secondary stroke prevention in highly selected patients. Further studies will be necessary to establish the efficacy and safety of endovascular treatment in larger series.     

Percutaneous transluminal angioplasty of extracranial vertebral artery stenosis--a case report

Due to improvement in intravascular therapeutic procedures significant stenoses of vertebral and basilar arteries can presently be treated by means of percutaneous transluminal angioplasty (PTA). The reported case was a 34-year-old man with symptomatic stenosis of the distal left vertebral artery and hypoplastic right vertebral artery. The patient underwent PTA and the lesion was sufficiently dilated. No complications occurred during or after the procedure. After a year duplex Doppler follow-up examination showed normal blood flow and patency of both vertebral arteries. PTA may prove to be a useful therapeutic option in patients with symptoms of vertebro-basilar insufficiency.     

Three-dimensional power-mode ultrasound for quantification of the progression of carotid artery atherosclerosis

Elucidation of the dynamic nature of plaque progression has important implications for clinicians. The present study sought to establish an in vivo method for visualizing structural changes in carotid plaques. Three-dimensional reconstruction of parallel two-dimensional gray-scale B-mode ultrasound combined with power-mode examination of 38 carotid artery plaques was performed in a prospective study of 32 patients (18 men, 14 women; mean age 67.5 ± 7.6 years). Initial mean plaque volume was 391 μl. After a mean of 18.9 months carotid artery plaque progression had occurred in 15% of carotid artery plaques, with plaque volume increasing 59% in these cases. Plaque volume remained constant, within a range of ± 20% in 85% of cases. Progressive plaques were predominantly hypoechoic (3/5 cases) or had an ulcerated surface in cases of a hyperechoic echogenicity (2/5 cases). Risk factors and drug therapy were unrelated to plaque progression. This study illustrates that the combination of three-dimensional ultrasound with power-mode imaging improves the separation of the intraluminal plaque surface from the vessel lumen. Three-dimensional reconstruction of atherosclerotic carotid artery plaques enables the reproducible quantification of plaque volume and is therefore an excellent technique for longitudinal trials assessing progression or regression of carotid artery disease. Received: 14 January 1999/Received in revised form: 27 August 1999/Accepted: 15 October 1999     

Idiopathic basilary artery occlusion in childhood (case report)

A case of basilar artery occlusion in a 16-year-old-girl has been reported. Reports of 20 such cases occurring in children have been reviewed. In children, basilar artery occlusion is more common in males; no previous case above the age of 3 years has been reported in females. There were preceding TIA's and RIND in the vertebro-basilar territory.     

Persistent primitive first cervical intersegmental artery (proatlantal artery II) with occlusion of the basilar artery--a case report

A rare case of persistent primitive first cervical intersegmental artery (proatlantal artery II) is reported. A 58-year-old man was admitted to our hospital with dysarthria and left hemiparesis. On admission he was stuporous with bilateral gaze palsy and left hemiparesis. CT scan on admission showed low density areas in the right cerebellar hemisphere and ventricular part of the pons. Right retrograde brachiography revealed occlusion of the basilar artery, aplasia of the right vertebral artery and an abnormal vessel connecting the right external carotid artery and the right vertebral artery. This anastomotic vessel was thought to be a persistent primitive first cervical intersegmental artery (Proatlantal artery II). Left carotid angiography revealed the left posterior cerebral artery was visualized through the posterior communicating artery, leading from the internal carotid artery. Left retrograde brachial angiography showed that the left vertebral artery terminated just distal from the branching of the left posterior inferior cerebellar artery. After admission the left hemiparesis deteriorated gradually and tracheotomy was done due to respiratory difficulties. The patient was then transferred to the rehabilitation center on his 34th day in hospital with neurological deficits.