Extracranial

Jovin TG, Gupta R, Uchino K, Jungreis CA, Wechsler LR, Hammer MD, Tayal A, Horowitz MB. Emergent stenting of extracranial internal carotid artery occlusion in acute stroke has a high revascularization rate. Stroke 2005 36 2426-2430. 

The timing of CEA after ischemic stroke has been a controversial issue. In 1969, the Joint Study of Extracranial Arterial Occlusion reported 42% mortality after CEA in patients with neurological deficits of less than 2 weeks duration, compared with 5% mortality in patients with more than 2 weeks of symptoms. Early evidence also demonstrated an increased risk of intracerebral hemorrhage after early CEA in patients with acute stroke. This led to the conclusion that most complications occurred with early surgical intervention, and resulted in a traditional 4-6 week delay for CEA after an acute stroke. In retrospect, however, there were major problems with patient selection in these earlier reports. Many of the patients... 

Connolly JE. The evolution of extracranial carotid artery surgery as seen by one surgeon over the past 40 years. Surgeon 2003 1 249-258. 

Blaisdell WE, Clauss RH, Galbraith JG, Imparato AM, Wylie EJ. Joint study of extracranial arterial occlusion. IV. A review of surgical considerations. JAMA 1969 209 1889 1895. 

Failure of extracranial-intracranial arterial bypass to reduce the risk of ischemic stroke. Results of an international randomized trial. The EC/IC Bypass Study Group. N Engl J Med 1985 313 1191-1200. 

Powers WJ, Grubb Jr, RL, Raichle ME. Clinical results of extracranial-intracranial bypass surgery in patients with hemod3mamic cerebrovascular disease. J Neurosurg 1989 70 61-67. 

Jinnouchi J, Toyoda K, Inoue T, Fujimoto S, Gotoh S, Yasumori K, Ibayashi S, lida M, Okada Y. Changes in brain volume 2 years after extracranial-intracranial bypass surgery a preliminary subanalysis of the japanese EC-IC trial. Cerebrovasc Dis 2006 22 177-182. 

Crowell RM, Olsson Y. Effect of extracranial-intracranial vascular bypass graft on experimental acute stroke in dogs. J Neurosurg 1973 38 26-31. 

Cl 0.08-0.96) and symptomatic pulmonary embolism (PE) (OR 0.34, 95% Cl 0.17-0.69), but an increase in major extracranial hemorrhage when compared to placebo (OR 2.17, 95% Cl 1.10. 28). Nonsignificant reductions in combined death and disability, as well as increases in case fatality and sICH were also observed. The authors concluded that insufficient evidence existed to support the routine use of LMWH in the management of patients with ischemic stroke. 

Groups assigned to a LMWH or heparinoid had a significant reduction in the odds of DVT (OR 0.52, 95% Cl 0.56-0.79). However, there were too few major events (PE, death, intracranial or extracranial hemorrhage) to provide a reliable estimate of other benefits or risks. 

Overall no evidence was found to support the claim that anticoagulants offer a net advantage over aspirin in patients with acute ischemic stroke. There was evidence, however, to suggest that combination anticoagulant and aspirin therapy was associated with a small increase in the number of deaths at the end of follow-up, equivalent to 20 more deaths per 1000 patients treated. This adverse effect can probably be attributed partly to the 10 extra sICHs, and the 5 extra major extracranial hemorrhages per 1000 patients treated with combination anticoagulant/ aspirin therapy. 

Engelter S, Lyrer P, Kirsch E, Steck AJ. Long-term follow-up after extracranial internal carotid artery dissection. Eur Neurol 2000 44 199-204. 

Malek AM, Higashida RT, Phatouros CC, Lempert TE, Meyers PM, Smith WS, Dowd CP, Halbach VV. Endovascular management of extracranial carotid artery dissection achieved using stent angioplasty. AJNR Am J Neuroradiol 2000 21 ... 

Carotid Doppler studies will determine whether the patient has a high degree of stenosis in the carotid arteries supplying blood to the brain (extracranial disease). 

Low-molecular-weight heparins and heparinoids are not recommended in the treatment of acute ischemic stroke.11 A meta-analysis was performed using data from 10 randomized controlled trials.19 A non-significant decrease in combined death and disability and a non-significant increase in case fatality and hemorrhage were seen. A reduction in venous thromboembolic events was observed in acute stroke patients however, there was also an increase in extracranial bleeding. 

Brain metastasis is common in melanoma, and treatment options for brain metastasis include surgery, radiation, and chemotherapy. The choice of therapy depends on the number of metastatic lesions, accessibility of the lesions for surgery, the presence of neurologic symptoms, and the status of extracranial disease. 

Ischemic strokes account for 88% of all strokes and are due either to local thrombus formation or to emboli that occlude a cerebral artery. Cerebral atherosclerosis is a causative factor in most cases of ischemic stroke, although 30% are of unknown etiology. Emboli can arise either from intra- or extracranial arteries. Twenty percent of embolic strokes arise from the heart. 

Ergotamine reduces extracranial blood flow, causes a decline in the amplitude of... 

Brown, A.B., Yang, W., Schmidt, N.O., Carroll, R., Leishear, K.K., Rainov, N.G., Black, P.M., Breakefield, X.O., Aboody, K.S. (2003). Intravascular delivery of neural stem cell lines to target intracranial and extracranial tumors of neural and non-ncural origin. Hum Gene Ther, 14, 1777-85. 

In the NCGS study extracranial non-leukemia malignancy rates were similarly not increased in patients treated with growth hormone compared with those who were not (102). 

Despite theoretical concerns, there is no evidence that either intracranial or extracranial malignancy, new or recurrent, is increased in subjects treated with growth hormone (97,98,99). Despite this, certain precautions are... 

Tuffli GA, Johanson A, Rundle AC, Allen DB. Lack of increased risk for extracranial, nonleukemic neoplasms in recipients of recombinant deoxyribonucleic acid growth hormone. J Clin Endocrinol Metab 1995 80(4) 1416-22. 

Pujia A, Rubba P Spencer M P Prevalence of extracranial carotid artery disease detectable by echo-Doppler in an elderly population. Stroke 1992 23 818-822. 

Mokri B, Silbert PL, Schievink WI et al (1996) Cranial nerve palsy in spontaneous dissection of the extracranial internal carotid artery. Neurology 46 356-359 Molina CA, Montaner J, Abilleira S et al (2001) Timing of Spontaneous Recanalization and Risk of Hemorrhagic Transformation in Acute Cardioembolic Stroke. Stroke 32 1079-1084 Molina CA, Alvarez-Sabin J, Montaner J et al (2002) Thrombolysis-related hemorrhagic infarction a marker of early reperfusion, reduced infarct size, and improved outcome in patients with proximal middle cerebral artery occlusion. Stroke 33 1551-1556... 

CE-MRA is currently the most used MRA technique for cervical carotids and other extracranial vessels of the body (Carr et al. 2002 Remonda et al. 2002). With 1.5-T magnets, however, the spatial resolution is still markedly inferior compared with TOF-MRA, since the time for data collection can not be extended over minutes. CE-MRA is increasingly used for intracranial indications as well (see below). The advantages are seen in a low sensitivity for signal loss due to turbulence (Fig. 5.2) or velocity displacements of streaming blood. This affords an opportunity to assess stenoses more reliably than with TOF or PC-MRA (Gottschalk et al. 2002), as long as sufficient anatomic resolution is provided. 

Atherosclerosis mainly affects large- and mediumsized arteries. Extracranial manifestations at the carotid bifurcation statistically dominate the intracranial arteries. Besides typical manifestations at the carotid siphon or the vertebrobasilar junction, atherosclerosis is occasionally also found in peripheral intracranial vessel segments. Typical sequelae of atherosclerosis are stenosing plaque formations, ulcerations, dilatations or the evolution of fusiform aneurysms, which can be accompanied by extensive formation of thrombus. 

Fig.5.21a,b. Subacute dissection of the extracranial right ICA. Spin-echo Tl-weighted images pre- (a) and post-fat saturation (b)... 

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