Intracranial arterial dissection

Dissection of the internal carotid and vertebral arteries is a common cause of stroke, particularly in young patients. Although many occur due to trauma, it is estimated that over half occur spontaneously. The mechanism of stroke following arterial dissection is either by artery-to-artery embolism, by thrombosis in situ, or by dissection-induced lumenal stenosis with secondary cerebral hypoperfusion and low-flow watershed infarction. Occasionally, dissection may lead to the formation of a pseudoaneurysm as a source of thrombus formation. Vertebrobasilar dissections that extend intracranially have a higher risk of rupture leading to subarachnoid hemorrhage (SAH). ° ... 

Lamy C, Giarmesini C, Zuber M et al. (2002). Clinical and imaging findings in cryptogenic stroke patients with and without patent foramen ovale the PFO-ASA Study (Atrial Septal Aneurysm). Stroke 33 706-711 Leung SY, Ng THK, Yuen ST et al. (1993). Pattern of cerebral atherosclerosis in Hong Kong Chinese severity in intracranial and extracranial vessels. Stroke 24 779-786 Leys D, Moulin Th, Stojkovic T et al. (1995). Follow-up of patients with history of cervical artery dissection. Cerebrovascular Diseases 5 43-49... 

The main clinical indications for imaging the cerebral circulation are TIA (e.g. to identify arterial stenosis), acute ischemic stroke (e.g. to identify vessel occlusion), intracerebral hemorrhage (e.g. to identify an underlying vascular malformation) and possible arterial dissection, flbromuscular dysplasia or other arteriopathies, cerebral aneurysm, intracranial venous thrombosis or cerebral vasculitis. 

Extracranial carotid atherosclerosis or intimal hyperplasia Intracranial atherosclerosis Aortic atherosclerosis Extracranial arterial dissection... 

Infrequently, cervical artery dissection can lead to subarachnoid hemorrhage, usually when the dissection extends to the intracranial part of the vessel, with pseudoaneurysm formation and rupture (1% of cervical artery dissection cases in the large hospital-based series) [36, 37], Rupture of dissected vertebral arteries into the subarachnoid space is more common in children. Rupture of dissected carotid artery pseudoaneurysms into the neck or nasal sinuses is generally rare. Dissection can occur intracraiually and, on rare occasions, can spread intracraniaUy from a primary extracranial origin. 

Spontaneous arterial dissection has been well recognized at the cervical portion of the carotid artery and extracranial vertebral artery as an important cause of ischemic stroke in young adults. In contrast, intracranial or intradural dissections more... 

Albuquerque PC, Fiorella DJ, Han PP, Deshmukh VR, Kim LJ, McDougall CG (2005) Endovascular management of intracranial vertebral artery dissecting aneurysms. Neu-rosurg Focus 18(2) E3... 

A systematic review of all prospective studies of the risks associated with spinal manipulation included five primary investigations (150). The most valid studies suggested that about half of all patients who see a chiropractor will have adverse effects, which are usually mild and transient. No reliable data about serious adverse events were uncovered. However, a review of recent case reports has shown that spinal manipulation was associated with several serious adverse effects, including dissection of the vertebral and internal carotid arteries, resulting in strokes and at least one death (151). Other instances relate to epidural hematoma, intracranial aneurysm, cauda equina syndrome, contusion of the spinal cord, myelopathy, radiculopathy, and palsy of the long thoracic nerve. 

Neurosurgery 40 651-662 discussion 662-663 Schievink WI (2001) Spontaneous dissection of the carotid and vertebral arteries. N Engl J Med 344 898-906 Schievink WI, Wijdicks EF, Piepgras DG, Chu CP, O Fallon WM, Whisnant JP (1995) The poor prognosis of ruptured intracranial aneurysms of the posterior circulation. J Neurosurg 82 791-795... 

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