Intracranial rupture

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). ° ... 

Hemorrhagic strokes account for 12% of strokes and include subarachnoid hemorrhage, intracerebral hemorrhage, and subdural hematomas. Subarachnoid hemorrhage may result from trauma or rupture of an intracranial aneurysm or arteriovenous malformation. Intracerebral hemorrhage occurs when a ruptured blood vessel within the brain parenchyma causes formation of a hematoma. Subdural hematomas are most often caused by trauma. 

In subarachnoid hemorrhage due to a ruptured intracranial aneurysm or arteriovenous malformation, surgical intervention to clip or ablate the vascular abnormality substantially reduces mortality from rebleeding. The benefits of surgery are less well documented in cases of primary intracerebral hemorrhage. In patients with intracerebral hematomas, insertion of an intraventricular drain with monitoring of intracranial pressure is... 

Oyesiku NM, Colohan AR, Barrow DL, Reisner A. Cocaine-induced aneurysmal rupture an emergent negative factor in the natural history of intracranial aneurysms Neurosurgery 1993 32(4) 518-26. 

Intracranial dissection is much rarer. It may present with subarachnoid hemorrhage owing to rupture of a pseudo-aneurysm, as well as with ischemic stroke, and is less often diagnosed during life (Farrell et al. 1985 de Bray et al. 1997 Chaves et al. 2002). 

Moyamoya seems to be mainly confined to the Japanese and other Asians, and in most cases the cause is unknown (Bruno et al. 1988 Chiu et al. 1998). Some cases are familial (Kitahara et al. 1979) others appear to be caused by a generalized fibrous disorder of arteries (Aoyagi et al. 1996), and a few may result from a congenital hypoplastic anomaly affecting arteries at the base of the brain, or associated with Down s syndrome (Cramer et al. 1996). The syndrome may present in infancy with recurrent episodes of cerebral ischemia and infarction, mental retardation, headache, epileptic seizures and, occasionally, involuntary movements. In adults, subarachnoid or primary intracerebral hemorrhage are also common owing to rupture of collateral vessels. There have also been a few reports of associated intracranial aneurysms (Iwama et al. 1997) and also of cerebral arteriovenous malformations. 

Embolism from thrombus within the cavity of an aneurysm is rare and is difficult to prove in cases where there maybe other potential sources of embolization. Intracranial aneurysms more commonly present with rupture and subarachnoid hemorrhage, whereas internal carotid artery aneurysms tend to cause pressure symptoms including a pulsatile and sometimes painful mass in the neck or pharynx, ipsilateral Horner s syndrome or compression of the lower cranial nerves. Extracranial vertebral artery aneurysms may cause pain in the neck and arm, a mass, spinal cord compression and upper limb ischemia (Catala et al. 1993). 

The hematoma continues to expand after stroke onset, frequently causing further deterioration (Brott et al. 1997 Leira et al. 2004). Some brainstem hemorrhages evolve subacutely, particularly those caused by a vascular malformation (O Laoire et al. 1982 Howard 1986). Any large hematoma may cause brain shift, transtentorial herniation, brainstem compression and raised intracranial pressure. Hematomas in the posterior fossa are particularly likely to cause obstructive hydrocephalus. Rupture into the ventricles or on to the surface of the brain is common, causing blood to appear in the subarachnoid space. 

International Study of Unruptured Intracranial Aneurysms Investigators (1998). Unruptured intracranial aneurysms risks of rupture and risks of surgical intervention. New England Journal of Medicine 1998 339 1725-1733... 

A ruptured middle cerebral artery aneurysm originating from the site of anastomosis 20 years after extracranial-intracranial bypass for moyamoya disease case report. Surgical Neurology 64 261-265... 

Huang J, van Gelder JM (2002). The probability of sudden death from rupture of intracranial aneurysms a meta-analysis. Neurosurgery 51 1101-1107... 

Rinkel GJE, Djibuti M, AJgra A et al. (1998). Prevalence and risk of rupture of intracranial aneurysms a systematic review. Stroke 29 251-256... 

New England Journal of Medicine 336 28-40 Schwartz TH, Solomon RA (1996). Perimesencephalic nonaneurysmal subarachnoid hemorrhage review of the literature. Neurosurgery 39 433-440 Sluzewski M, van Rooij WJ, Beute GN et al. (2005). Late rebleeding of ruptured intracranial aneurysms treated with detachable coils. American Journal of Neuroradiology 26 2542-2549 Smith ER, Carter BS, Ogilvy CS (2002). 

ADPKD families haye a strong family history of intracranial artery aneurysm rupture. Hypertension is an early and frequent manifestation and gross hematuria is a common presenting symptom. 

Irsigler FJ A case of methyl bromide poisoning simulating rupture of an intracranial aneurysm. S AfrMedJ 25 949-952, 1951... 

A cerebral hemorrhage is the result of rupture of a sclerosed or otherwise diseased blood vessel in the brain. The brain cells in the vicinity of the burst vessel are deprived of blood and therefore nutrients. They will mostly die within several minutes. The symptoms may be mild to severe, including loss of speech and memory, as well as an inability to walk. It is believed that atherosclerosis, combined with hypertension, predisposes a person to such a CVA. Intracranial bleeding can also result from a head injury or from the interaction of certain antidepressant drugs with other drugs or even particular foods. 

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. 

Subarachnoid hemorrhage (SAH) is most commonly caused by rupture of an intracranial aneurysm. It can produce vasospasm that may cause ischemia and infarction. Currently, vasospasm has surpassed rebleeding as the most important complication after rupture of an aneurysm. Vasospasm due to SAH is thought to occur in the majority of cases of SAH (angiographic vasospasm is detectable in perhaps as many as 60-70% of patients after subarachnoid hemorrhage), but is symptomatic only in about a third of this population [81]. Symptomatic vasospasm carries a 15% to 20% risk of stroke or death. Vasospasm peaks around 1 week after SAH, but it can be seen as early as 3 days or as late as 3 weeks after the initial event [82], The underlying mechanisms are not understood, but vasospasm is clearly related to the amount of blood and its location in the subarachnoid space. Clinical symptoms generally develop slowly over a period of several hours to 1 or 2 days however, clinical evolution can be rapid in the onset with a stroke-like presentation [81, 82]. 

International Subarachnoid Aneurysm Trial (ISAT) Collaborative Group. (2002) International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms a randomised trial. The Lancet, 360, 1267-1274. 

Shape memory PU has been proposed as a candidate for aneurysm coils [106]. An intracranial aneurysm can go undetected until the aneurysm ruptures, causing... 

---