Aneurysms vasospasm

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]. 

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Parra A, Kreiter KT, Williams S, Sciacca R, Mack WJ, Naidech AM, Commichau CS, Fitzsimmons BF, Janjua N, Mayer SA, Connolly Jr. ES, Effect of prior statin use on functional outcome and delayed vasospasm after acute aneurysmal subarachnoid hemorrhage a matched controlled cohort study. Neurosurgery 2005 56 476 84 [discussion 476 84]. 

Tseng MY, Czosnyka M, Richards H, Pickard JD, Kirkpatrick PJ. Effects of acute treatment with pravastatin on cerebral vasospasm, autoregulation, and delayed ischemic deficits after aneurysmal subarachnoid hemorrhage a phase II randomized placebo-controlled trial. Stroke 2005 36 1627-1632. 

Kassell, N.F., Haley, E.C., Halves, W.M., Hunsen, C.A. and Weir, B. (1993). Phase two trial of tirilazad in aneurysmal subarachnoid hemorrhage. Vth International Symposium on Cerebral Vasospasm, Edmonton and Jasper, Alberta, Canada, May 18-21. Can. J. Neurol. Sci. 20, S29. 

Cerebral vasospasm following aneurysmal subarachnoid haemorrhage is one... 

Conway JE, Tamargo RJ. Cocaine use is an independent risk factor for cerebral vasospasm after aneurysmal subarachnoid hemorrhage. Stroke 2001 32(10) 2338-43. 

For subarachnoid hemorrhage surgical clipping of the causative aneurysm or resection of the arteriovenous malformation is the mainstay of treatment. Endovascular coiling of the aneurysm can also be performed. Post-operative infection (either brain or respiratory) is an uncommon complication and not believed to be any more common than after other invasive surgical procedures. Hypervolemic-hemodilution and hypertensive (HHH) therapy is used to prevent spasm. There may be a role for anti-inflammatory measures for the prevention of vasospasm and delayed cerebral ischemia, as shown in a recent pilot study of patients treated with statins (Lynch et al., 2005). 

Lynch JR, Wang H, McGirt MJ, Floyd J, Friedman AH, Coon AL, Blessing R, Alexander MJ, Graffagnmo C, Wai iier DS, Laskowitz DT (2005) Simvastadn reduces vasospasm after aneurysmal sub-ai aclnioid hemon liage Results of a pilot randomized clinical tiial. Sti oke 36 2024-2026. 

Adverse effects/complications Coils delivered at the rupture site may perforate the vessel wall (or pseudo-wall in case of an aneurysm) and aggravate the bleeding. Coil placement may also provoke or increase vasospasm. 

Sensory systems Eyes A 55-year-old woman developed choroidal infarction with permanent visual loss after intracranial irrigation with papaverine 3 ml (30 mg/ml), used to prevent postoperative vasospasm after surgical clipping of a left middle cerebral artery aneurysm [161 ]. 

Hydrocephalus, rebleeding from aneurysmal rerupture and cerebral vasospasm with ischemia are the three major complications following SAH. 

Fig. 5.34a-c. Patient after SAH with a basilar tip aneurysm seen on CTA in an outside hospital. a Initial DSA did show vasospasm of the PI segment and the superior cerebellar artery on both sides. In addition, some irregularity at the tip of the basilar artery was noted but no real aneurysm, b Repeated DSA 2 months later showed a small basilar tip aneurysm suitable for endovascular treatment, c The patient was scheduled for embolization 10 days later but the aneurysm again was not visible. The patient was referred to surgery... 

Fig. 5.39a,b. Right MCA infarct in a patient who was administered with mild left sided hemiparesis. Doppler sonography revealed slightly increased velocity of the ICA and MCA and lumbar puncture showed hemosiderin. The patient did not report a typical sudden onset of headache. DSA revealed a small Pcom aneurysm but no visible vasospasms... 

Various nondetachable balloons are available for temporary vessel occlusion, angioplasty for vasospasm therapy or remodelling techniques for broad based aneurysms. Larger vessels like the carotid or vertebral artery can be occluded with a double lumen balloon catheter, i.e. Meditech (Cook). For intracranial angioplasty and remodeling smaller, more flexible balloons, like the Hyperglide (MTI), Eclipse (Balt), or the Copernic (Balt) are required. Additionally to these balloons tbe Hyperform microballoon (MTI) can be used for remodelling technique. 

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