1/6. Different roles of arteriosclerosis in the rupture of intracranial dissecting aneurysms.AIMS: Although intracranial dissecting aneurysm (IDA) is a newly described variant of the brain aneurysms that affects mainly the vertebrobasilar arterial system, its pathogenesis remains obscure. We aimed to clarify the role of arteriosclerosis in the pathogenesis of IDA based on histopathological findings in seven autopsy cases of IDA. methods AND RESULTS: All cases exhibited systemic hypertension or left ventricular hypertrophy. Macroscopically, all cases exhibited subarachnoid haemorrhage. Two types of dissection were recognized in the vertebral artery. Six of seven IDA cases showed a widespread disruption of the entire thickness of the arterial wall with the formation of a dilated pseudoaneurysm, which consisted of thin adventitia (arterial wall disruption type). Medial disruption of the arterial wall and subadventitial dissecting haemorrhage were also found, resulting in the formation of a false lumen and stenosis of the 'true' lumen of the artery. However, these lesions were connected to the site of rupture of the entire arterial wall. Within 1 day after onset of IDA, the autopsy cases showed formation of fibrin thrombus, marked leucocyte infiltration and necrosis of the arterial wall at the site of the lesion. Cases that survived more than 1 week showed smooth muscle cell proliferation, macrophage accumulation and lymphocytic infiltration in the lesions. These cases showed no atherosclerotic plaque, but non-atherosclerotic fibrocellular intima. The thickness of intima and media was significantly less in the vertebral artery of IDA patients than that of non-IDA patients with systemic hypertension. On the other hand, the remaining case showed severe atherosclerosis with haemorrhage into the lipid core without connection to the arterial lumen (intra-atheromatous plaque haemorrhage type). However, unusual arterioles and neovascularization of the intra-and peri-arterial walls were observed. CONCLUSIONS: Our results suggest that disruption of the entire arterial wall may be a critical event in the development of IDA and result in the medial disruption and subadventitial haemorrhage. Non-atheromatous intima might function as a protective factor in arterial wall disruption. On the other hand, atherosclerosis may predispose to intra-atheromatous plaque haemorrhage type of IDA through intramural haemorrhage originating from the newly formed vessels.- - - - - - - - - - ranking = 1keywords = haemorrhage (Clic here for more details about this article) |
2/6. A ruptured dissecting aneurysm of the vertebral artery: comparison of angiographic and histological findings.We present autopsy findings in a patient with a dissecting aneurysm of the vertebral artery causing subarachnoid haemorrhage. We sectioned the artery longitudinally and compared it with the angiogram, which showed the "pearl-and-string". Histological examination showed a pseudoaneurysm covered by adventitia alone, forming the "pearl". Internal elastic lamina and media were destroyed, and haematoma extended in the subadventitial space of the wall of the pseudoaneurysm. Media thickened by haematoma caused the "string", narrowing the parent artery. alcian blue staining showed that stratified internal elastic lamina in the aneurysm and the parent artery, had undergone marked mucoid degeneration, which may have been responsible for the dissection.- - - - - - - - - - ranking = 0.14285714285714keywords = haemorrhage (Clic here for more details about this article) |
3/6. The use of CT-angiography for monitoring thrombus formation after balloon occlusion of a dissecting vertebral artery pseudoaneurysm.We present a 49-year-old man with a subarachnoid haemorrhage from a dissecting vertebral artery (VA) pseudoaneurysm treated with a proximal balloon occlusion. The clinical course was complicated by the sudden appearance of a lateral medullary syndrome (Wallenberg), which completely resolved after anticoagulant therapy. During this course, CT-angiography (CTA) enabled monitoring of both the progression and partial resolution of the thrombus in the occluded VA. An anatomical variant of a perforating artery originating from the VA proximal to the posterior inferior cerebral artery (pica) was subsequently demonstrated, explaining the ischemic event. The value of CTA in clinical management is discussed. The prophylactic use of anticoagulant therapy especially in the case of a perforating artery to the lateral medulla originating proximally to the pica, is suggested.- - - - - - - - - - ranking = 0.14285714285714keywords = haemorrhage (Clic here for more details about this article) |
4/6. Simultaneous dissection of intra- and extracranial vertebral artery. Report of two cases and review of literature.Two patients who developed subarachnoid haemorrhage are presented. The first patient was a 41-year-old woman whose angiograms showed right extracranial vertebral artery (VA) dissection starting at the C2 level extending to the intracranial VA near the VA union. Proximal occlusion of the right VA by the endovascular approach was performed. The second patient was a 57-year-old man whose angiograms showed the left intracranial VA dissection distal to the posterior inferior cerebellar artery and an extracranial aneurysmal dilatation of the left VA at the C1 level and extracranial VA dissection in the V3 portion of the right VA. Left intracranial VA dissection was surgically trapped, and the remaining lesions were conservatively treated.Simultaneous dissection of the intracranial and extracranial portions of the VA is rare. Such lesions usually cause brain ischaemia, but may cause intracranial subarachnoid haemorrhage.- - - - - - - - - - ranking = 0.28571428571429keywords = haemorrhage (Clic here for more details about this article) |
5/6. Endovascular and surgical management of vertebral artery dissecting aneurysms presenting with subarachnoid haemorrhage: medium-term experience.INTRODUCTION: Dissecting aneurysms of the vertebral artery are associated with a high incidence of rebleeding and mortality if untreated. Current endovascular alternatives to surgery are being evaluated. MATERIALS AND methods: We conducted a retrospective review of our experience with endovascular as well as surgical treatments of dissecting vertebral artery aneurysms in 6 patients. Three patients were treated with a combination of coils in the proximal artery and aneurysm sac; 1 with a combination of coils and balloon; and 2 with aneurysm clipping surgery. All patients were treated with the primary intention of coil deposition within the aneurysm sac and proximal vertebral artery. No proximal flow arrest was used. Anticoagulation was given during and after the procedure. RESULTS: Technical success was achieved in all patients, and there was no postprocedural neurological deficit. Follow-up for a mean of 40 months (range, 7 to 64) confirmed the clinical stability of symptoms, as well as the cessation of flow to the aneurysm. CONCLUSIONS: Endovascular treatment of vertebral artery dissections is a viable alternative to surgery in the appropriate setting. It has the benefit of being minimally invasive, allowing concomitant balloon testing as well as retaining the option to convert to surgery.- - - - - - - - - - ranking = 0.57142857142857keywords = haemorrhage (Clic here for more details about this article) |
6/6. vertebral artery dissection and cerebellar infarction following chiropractic manipulation.vertebral artery dissection (VAD) associated with chiropractic cervical manipulation is a rare but potentially disabling condition. In this report, we present a young patient manifesting with repeated vertigo. Owing to the initial misdiagnosis, the patient later developed cerebellar stroke with inability to stand or walk. vertigo and disequilibrium are the usual presenting symptoms of this condition, which can result from inner ear or vestibular nerve dysfunction, vertebrobasilar insufficiency, and even lethal cerebellar infarction or haemorrhage; these last two, although rarely seen in young adults, can be caused by traumatic or spontaneous arterial injury, including injury secondary to chiropractic cervical manipulation. A number of cases of VAD associated with chiropractic cervical manipulation have been reported, but rarely in the emergency medicine literature. We present a case of this rare occurrence, and discuss the diagnostic pitfalls.- - - - - - - - - - ranking = 0.14285714285714keywords = haemorrhage (Clic here for more details about this article) |