A dissecting aneurysm of the vertebral artery

A rare case of dissecting aneurysm of the vertebral artery evidenced by ischemic attacks is reported. The aneurysm was treated by proximal ligation of the artery. There have been no repeated ischemic attacks and bleeding for 20 months. Analysis of 51 cases of vertebral artery aneurysm failed to disclose any comparable case. A review of the literature also revealed that clinically diagnosed dissecting aneurysms of the vertebrobasilar system have been reported rarely. Most of these cases were found at autopsy.     

椎动脉-小脑后下动脉梭形动脉瘤的手术治疗

目的 探讨手术治疗椎动脉-小脑后下动脉梭形动脉瘤的方法.方法 回顾性分析2007年12月至2010年2月收治的5例椎动脉-小脑后下动脉梭形动脉瘤患者的临床特点、手术方法及疗效.5例患者均为男性,年龄40～55岁,平均47岁.其中动脉瘤破裂出血4例,1例表现为后枕部阵发性头痛.所有患者均采用远外侧入路,翻开皮肌瓣后,先于枕部肌群内分离枕动脉,开颅后显露同侧小脑后下动脉尾襻,并于此处行枕动脉-小脑后下动脉吻合重建小脑后下动脉血流,再行动脉瘤孤立术或切除术.术后进行随访,观察疗效.结果 5例患者术后1例无神经功能缺失;3例有后组脑神经功能障碍;1例出现颅内血肿,二次手术后并发对侧肢体偏瘫.行数字减影血管造影或CT血管造影检查,吻合口通畅,动脉瘤不显影.随访2～29个月,平均18个月,4例预后良好,1例对侧肢体轻偏瘫.结论 枕动脉-小脑后下动脉搭桥+动脉瘤孤立或切除术是治疗椎动脉-小脑后下动脉梭形动脉瘤的有效方法,但需结合实际情况,选择个体化的治疗方案.     

Dissecting aneurysms of the vertebrobasilar system. A comprehensive review on natural history and treatment options

Vertebral artery dissection has been recognized as an uncommon cause of ischemic stroke. However, it is less well known as a cause of subarachnoid hemorrhage. Even if dissecting aneurysms of the vertebral artery are rare, their importance arise from their high morbidity and mortality with rebleeding occurring more often than in cases of saccular aneurysms. Dissecting aneurysms of the vertebrobasilar system are a complex entity which requires a rapid and effective treatment to prevent rerupture. The sole stenting technique stands as a promising approach, allowing to occlude the aneurysm while preserving the vessel patency and reconstructing the diseased segment.     

Endovascular coil trapping for ruptured vertebral artery dissecting aneurysms by using double microcatheters technique in the acute stage

Summary ?Background. In the treatment of vertebral artery (VA) dissecting aneurysms, only proximal occlusion of the VA does not necessarily prevent rerupture. We evaluated the efficacy of coil trapping for the ruptured VA dissecting aneurysms using the double microcatheters technique. Methods. We treated 11 patients who presented with subarachnoid haemorrhage (SAH) due to rupture of a VA dissecting aneurysm which did not involve the posterior inferior cerebellar artery at the site of dissection. All patients tolerated the balloon occlusion test. Within 3 days of the SAH, the dissection site was trapped with a Guglielmi detachable coil (GDC) using the double microcatheters technique. The proximal and distal sites of the dissecting aneurysm were embolized simultaneously. Findings. GDC trapping at the affected site was successful in all 11 patients. Radiographic findings showed complete occlusion of the dissection site and patency of the unaffected artery. Although one patient experienced transient dysphagia, there were no major complications. Interpretation. The double microcatheters technique is effective for coil trapping of ruptured VA dissecting aneurysms in selected patients. The risks posed by this simple technique are minimal, even in the acute stage. Published online May 26, 2003     

Repeat angiography and magnetic resonance imaging (MRI) of dissecting aneurysms of the intracranial vertebral artery

Summary We here present 4 cases with dissecting aneurysm (DA) of the intracranial vertebral artery, who were followed up by repeat cerebral angiography and MRI. The patients consisted of 2 males and 2 females, and the mean age was 43 years. Two cases were associated with polyarteritis nodosa (PN) and hypertension, respectively. Three of the cases developed subarachnoid haemorrhage (SAH), while the other one suffered from lateral medullary syndrome.In cerebral angiography, pearl and string signs were revealed in all cases, while a double lumen indicating a true diagnostic sign of DA was demonstrated in only one case. Repeat angiography showed that a bleb formation with a bulging of the aneurysmal sac was seen in 2 cases, and an irregularity of the wall in one case. On the other hand in one case, the ectatic part shrank, while the stenotic part was restored.In magnetic resonance imaging (MRI), a hyperintensity mass on T 1-weighted image (T 1-WI) adjacent to flow void suggesting either an intramural haematoma or a linear shape hyperintensity on T1-WI were demonstrated in 3 cases. In the follow up MRI done in 2 cases, a serial change in the intensity from iso-intensity to hyperintensity on T 1-WI was observed in one case suggesting intramural haemorrhage, while an enlargement of the ectatic flow void was seen in the other case.Three of 4 cases were operated on by trapping of the aneurysms. One, who had systemic vascular diseases due to PN, and repeat angiography showed a regression of the aneurysm, was conservatively treated. The outcome was excellent in the 3 surgical cases, whilst the one medically treated case was also excellent without any rebleeding.In conclusion, repeat neuro-imaging procedures are strongly recommended to clarify the possibility of a spontaneous repair of the dissection, and to consider the surgical strategy for the lesion.     

Proximal clipping and bypass between bilateral vertebral arteries using a radial arterial graft for the treatment of a dissecting aneurysm of the vertebral artery

Proximal clipping has been performed recently as the main surgical treatment for a dissecting aneurysm of the vertebral artery. When there is a contralateral vertebral artery of a smaller size with arteriosclerotic changes, some form of bypass to prevent cerebellar and brain stem infarction is needed in addition to proximal clipping. We treated a 50-year-old man with a ruptured dissecting aneurysm of the left vertebral artery and stenosis at the V3 segment of the right vertebral artery. The caliber of the right vertebral artery was smaller than the left. After an anastomosis between bilateral vetebral arteries using a radial arterial graft, dissecting aneurysm was clipped at the proximal portion of the aneurysm.     

Dissecting aneurysm of basilar artery presenting with recurrent subarachnoid hemorrhage

Spontaneous basilar dissecting aneurysms secondary to subarachnoid hemorrhage are rare, usually presenting with ischemia rather than a subarachnoid hemorrhage (SAH). A 63-year-old man who had SAH repeatedly from a ruptured basilar dissecting aneurysm was treated with endovascular occlusion of the unilateral vertebral artery. Postoperative angiograms 1 month after the procedure showed complete obliteration of the aneurysm. The clinical follow-up at 20 months showed no evidence of recurrent hemorrhage. Received: 24 August 1998 / Accepted: 15 December 1998     

Isolated dissections and dissecting aneurysms of the posterior inferior cerebellar artery: topic and literature review

Isolated dissections of the posterior inferior cerebellar artery (PICA) are rare. Thus, no large series of cases have been reported in the literature. Due to limited knowledge regarding the natural history of these lesions and the lack of high-quality evidence supporting various treatment options, management is controversial and practice parameters are ill defined. In order to offer a comprehensive reference for the diagnosis and management of isolated PICA dissections, the authors reviewed the National Library of Medicine from 1966 to October 2001. Twenty-seven patients averaging 43.6 years of age and including 14 males and 13 females were reported. Subarachnoid hemorrhage occurred in 20 patients, and two died. Dissections were located in the proximal PICA in 22 patients and were three times more common on the left side (left:right=3:1). Six patients were managed conservatively, and four with endovascular techniques. Seventeen had open surgery: five underwent resection, two went through trapping, and two had proximal clipping. Wrapping with muscle was performed in two patients, encasement with Sundt clips in two, and four had occipital artery (OA)-PICA bypass surgery. A meticulous analysis of reported cases with regard to clinical and pathological features, management strategies, and outcomes is presented.     

弹簧圈栓塞动脉瘤及载瘤动脉治疗出血性椎动脉夹层动脉瘤

目的探讨采用弹簧圈栓塞动脉瘤及载瘤动脉治疗出血性椎动脉夹层动脉瘤的疗效及并发症。方法收集经颅脑CT及全脑DSA确诊的椎动脉夹层动脉瘤破裂出血患者17例,采用弹簧圈栓塞动脉瘤及载瘤动脉,观察疗效及并发症。结果 17例动脉瘤及载瘤动脉均完全闭塞,无死亡病例。术后当天1例发生Wallenberg综合征,恢复良好;1例术后3个月出现脑积水,行侧脑室-腹腔分流术后遗留轻度残疾;随访2~36个月,无再出血病例。术后6个月12例接受DSA复查,动脉瘤完全不显影,载瘤动脉未发生再通。结论应用弹簧圈栓塞夹层动脉瘤及载瘤动脉治疗出血性椎动脉夹层动脉瘤疗效确切,具有一定应用价值。     

Iatrogenic dissecting aneurysm of the internal carotid artery

Summary A secondary dissecting aneurysm after arterial injury has been reported as a complication of surgery. We encountered this phenomenon in a patient with a meningioma of the sphenoid ridge. Despite successful clipping of a small rupture in the anterior wall of the proximal portion of the internal carotid artery, the patient became drowsy 30 days after surgery and developed right hemiparesis followed by fatal bleeding from the internal carotid artery. Histological examination revealed a traumatic dissecting aneurysm which had developed from the tear in the intima and extended into the dural ring and the bifurcation of the carotid artery. The characteristic clinical and histopathologic findings are shown. Methods for early recognition and the possibility of immediate treatment are briefly discussed.     

Ruptured anterior communicating artery aneurysms associated with fenestration of the anterior cerebral artery

Two patients with ruptured anterior communicating artery aneurysms associated with fenestration of the anterior cerebral artery are reported. In the literature, only 12 angiographic demonstrations of fenestration of the anterior cerebral artery have been reported. All fenestrations were limited to the distal half of the A1 portion, and seven of the 12 cases were associated with aneurysms. The high incidence of coexisting fenestration and aneurysm suggests that congenital factors may play a role in the pathogenesis of cerebral aneurysm.     

The size of cerebral aneurysms in relation to repeated rupture

The size of ruptured cerebral aneurysms in 407 cases were studied angiographically in relation to the number of times of rupture. The size of aneurysms was not influenced by the number of clinically documented episodes of bleeding. Patients with long-term clinical courses of untreated ruptured aneurysms had significantly larger aneurysms than in the general patient population. The result indicates that aneurysmal enlargement is not closely related to their rupture when considering aneurysmal growth in general. The mechanism of growth of cerebral aneurysms is discussed.     

Spontaneous dissecting aneurysms of anterior and middle cerebral artery associated with brain infarction: a case report and review of the literature

BACKGROUND

Intracranial dissecting aneurysms have been reported with increasing frequency and are recognized as a common cause of stroke. In some reviews and case reports, attempts have been made to compare the outcomes of surgical and medical treatments. However, the appropriate management of dissecting aneurysms in the anterior circulation remains controversial, especially in patients who also manifest cerebral infarction.

CASE DESCRIPTION

A 45-year-old male was diagnosed as having a dissecting aneurysm of the right middle cerebral artery (MCA) with cerebral infarction. In the course of conservative treatment, he developed a new cerebral infarction in the territory of the right anterior cerebral artery (ACA). Repeat cerebral angiograms revealed an increase in the aneurysmal dilatation of the right M2 and the appearance of a segmental dilatation of the right A2. He continued to be treated conservatively and his course was satisfactory. On subsequent angiograms, we observed resolution of the right A2 dissection and no further progression of the dilatation of the right M2.

CONCLUSION

This is the first reported case of simultaneous idiopathic dissecting aneurysms of different major arterial branches in the anterior circulation. Our review of the literature disclosed 36 and 23 cases, respectively, of dissecting aneurysms of the ACA and MCA. Many previously reported patients with these dissecting aneurysms involving subarachnoid hemorrhage (SAH) underwent surgery, which resulted in better outcome. More than half of the patients with ACA and MCA dissecting aneurysms had cerebral infarction. All ACA dissecting aneurysms involving ischemia occurred in the A2 region. The outcomes of both surgical and conservative management were equally satisfactory. On the other hand, in patients with MCA dissecting aneurysms, the area of ischemia frequently involved the M1 region; in these patients, conservative treatment resulted in poor outcomes. Therefore, revascularization distal to the compromised artery should be considered in patients with MCA-dissecting aneurysms who have ischemia. Careful interpretation of serial angiograms and/or magnetic resonance (MR) images is necessary because of the possibility of disease progression. If the aneurysmal size increases or there is progression of ischemic symptoms in the course of conservative treatment, surgery must be urgently evaluated.     

Development of a dissecting aneurysm on the vertebral artery immediately after occlusion of the contralateral vertebral artery: A case report

A 49 year old female presented with subarachnoid hemorrhage due to a ruptured dissecting aneurysm on the left vertebral artery (VA). Following an occlusion test, we performed proximal occlusion of the left VA with detachable balloons. However, a dissecting aneurysm on the right VA developed three weeks later. After an occlusion test had showed no change in cerebral blood flow, auditory brain stem response, or neurological status, proximal occlusion of the right VA was performed. The patient has returned to normal life without neurological deficits. Bilateral dissecting aneurysms of the VA are quite common, but de novo VA dissecting aneurysms or enlargement of such aneurysms after occlusion of contralateral VA are rare. This case suggests that hemodynamic stress may be a causal factor in the development of VA dissecting aneurysms. Careful pre- and post-operative neuroradiological examination of the contralateral VA are required in patients under-going VA occlusion for dissecting aneurysms.     

Posterior inferior cerebellar artery aneurysm associated with arteriovenous malformation fed by the same artery

A 37-year-old man presented with a peripheral aneurysm of the left posterior inferior cerebellar artery associated with a more peripheral arteriovenous malformation fed by the same artery. Recurrent subarachnoid hemorrhage occurred from rupture of the aneurysm. Review of the pertinent literature indicates that the aneurysm of the posterior inferior cerebellar artery originates from the peripheral portion of the artery, when associated with arteriovenous malformation.     

血管内介入治疗大脑后动脉夹层动脉瘤

目的观察血管内介入治疗大脑后动脉夹层动脉瘤的效果。方法回顾性分析12例接受血管内介入治疗的大脑后动脉夹层动脉瘤患者,评价治疗效果。结果12例大脑后动脉夹层动脉瘤中,P1段2例,P1-P2段2例,P2段6例,P3段2例,均成功实施栓塞治疗;对其中2例单纯以弹簧圈栓塞动脉瘤,8例以弹簧圈闭塞载瘤动脉,2例植入支架。术后即刻行复查造影显示Raymond分级1级10例,2级2例。术后4例诉头痛,经对症治疗后2周内好转;未见动脉瘤破裂出血及脑梗死。随访期间影像学检查均未见动脉瘤复发,无新发神经功能障碍及颅内再次出血;末次随访时改良Rankin量表0分10例,1分1例,2分1例。结论血管内介入治疗大脑后动脉夹层动脉瘤效果较好,且安全性较高。     

三维CT血管造影对椎动脉的观察

目的探讨采用三维CT血管造影(3D-CTA)观察椎动脉的价值。方法对67例临床拟诊为椎动脉供血不足的患者行3D-CTA检查,容积重建(volumerendering,VR)和表面重建(shadedsurfacedisplay,SSD),其中7例行选择性椎动脉造影。结果67例患者中,椎动脉显像133条;正常52条,病变81条;1条闭塞不显像。病变包括先天性畸形,血管受压或牵拉移位,血管壁粗糙、钙化,管腔狭窄、部分中断等。发育畸形的椎动脉可伴有多种病变,一条椎动脉可以多段发病。椎动脉发育畸形和椎动脉各段病变发生情况如下:椎动脉先天畸形31条(发育纤细17条,走行异常14条);起始段(V1)病变11条(血管壁粗糙、变细10条,其中3条扭曲成角;1条钙化);颈椎段(V2)和寰枕段(V3)病变30条(骨质增生压迫血管移位13条,牵拉内移7条,局限性狭窄10条);颅内段(V4)病变55条(血管呈串珠状、管壁粗糙52条,其中钙化2条;血管部分中断3条)。血管造影7例14条血管,血管异常8条共13处病变;颅内段病变2处,3D-CTA显示明显狭窄,DSA为轻度狭窄,其余11处病变两者相符。结论3D-CTA能清晰显示椎动脉走行全程,同时可以观察与椎骨的解剖关系。在椎动脉先天畸形、血管钙化以及判断相邻椎骨的影响等方面优于其它影像方法,为椎动脉病变的诊断提供重要资料。     

Management of dissecting aneurysms of the posterior circulation

Summary We analysed the clinical presentation, treatment and outcome of our own 36 cases of posterior circulation dissecting aneurysms (DA) and discussed the surgical indications and procedures regarding posterior fossa DA. Twenty one cases were male, 15 cases were female. Their mean age was 54±14 years. Clinical manifestations were subarachnoid haemorrhage (SAH) in 14 cases (39%) and ischaemic attacks in 22 cases (61%). Three of 14 SAH cases had rebleeding in the acute stage. Angiographic findings were aneurysmal dilatation in 16 cases, retention of contrast medium in 12 cases, string sign in 9 cases, double lumen in 4 cases, pearl and string sign in 3 cases, and occlusion of parent artery in 2 cases. Surgical treatment was performed on nineteen cases (53%). The operation was carried out in the acute stage on the SAH group; in the subacute or chronic stage on the ischaemic group. The surgical procedure was the proximal ligation, trapping and removal of DA with or without revascularization of the parent artery. 84% of the surgically managed patients and 71% of the nonsurgical cases had a favourable outcome (good recovery or moderate disability). Poor prognosis was revealed from the rebleeding and primary neurological stage. We recommend surgical treatment in the acute stage on the SAH group. On the ischaemic group surgical treatment in the subacute or chronic stage is recommended, if the DA has the risk of rupture or progression of the dissection.     

Paediatric vertebral artery aneurysms: a literature review

Vertebral artery (VA) aneurysms in the paediatric population are a rare but a serious condition. However, the epidemiology of paediatric VA aneurysms is poorly understood and there is little consensus on what constitutes the appropriate treatment. Although multiple treatment options are available, including surgery, endovascular approaches, coil embolization and parent artery occlusion, there is limited clinical evidence regarding which approach is most optimal. This review outlines the current literature and evidence outlining the epidemiology, presentation, pathogenesis and treatment of paediatric VA aneurysms.     

Treatment of dissecting basilar artery aneurysm by flow reversal

Summary Dissecting aneurysm of the basilar artery is a rare but increasingly recognized entity, with a frequently fatal or morbid outcome. Unlike the well established proximal occlusion and trapping approaches to vertebral artery dissections, surgical intervention for basilar lesions has been limited to wrapping techniques for arterial wall reinforcement. We report a case of midbasilar dissecting aneurysm successfully treated by clipping the proximal basilar artery below the level of the anterior inferior cerebellar arteries, allowing retrograde flow via the posterior communicating arteries to provide continued basilar perfusion. With the growing recognition of basilar dissection and pseudoaneurysm formation there is a need for improved therapeutic options. We suggest that definitive treatment can be achieved using the principle of proximal occlusion and flow reversal, and review the pertinent literature on basilar artery dissection.