%0 Journal Article
%T Evidence-Based Cerebral Vasospasm Surveillance
%A Heather Kistka
%A Michael C. Dewan
%A J. Mocco
%J Neurology Research International
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/256713
%X Subarachnoid hemorrhage related to aneurysmal rupture (aSAH) carries significant morbidity and mortality, and its treatment is focused on preventing secondary injury. The most common¡ªand devastating¡ªcomplication is delayed cerebral ischemia resulting from vasospasm. In this paper, the authors review the various surveillance technologies available to detect cerebral vasospasm in the days following aSAH. First, evidence related to the most common modalities, including transcranial doppler ultrasonography and computed tomography, are reviewed. Continuous electroencephalography and older instruments such as positron emission tomography, xenon-enhanced CT, and single-photon emission computed tomography are also discussed. Invasive strategies including brain tissue oxygen monitoring, microdialysis, thermal diffusion, and jugular bulb oximetry are examined. Lastly, near-infrared spectroscopy, a recent addition to the field, is briefly reviewed. Each surveillance tool carries its own set of advantages and limitations, and the concomitant use of multiple modalities serves to improve diagnostic sensitivity and specificity. 1. Introduction Subarachnoid hemorrhage (SAH) resulting from a ruptured intracranial aneurysm affects approximately 30,000 individuals in USA each year [1]. While many of these patients die before reaching a hospital, the majority are admitted to an intensive care unit where their clinical status can be closely monitored. The damage created by the initial insult of an SAH is irreversible. Therefore, treatment of SAH patients is focused on preventing secondary injury in an effort to minimize morbidity and mortality. The most devastating injury is also among the most common: delayed cerebral ischemia (DCI). Delayed cerebral ischemia affects approximately 30% of all SAH patients and is correlated with a poor outcome as measured by long-term disability and mortality [2, 3]. There have been inconsistencies in the literature regarding the definition of DCI and its frequent precursor, vasospasm. As not all DCI is preceded by vasospasm, this has led to recent efforts to standardize terminology. In general, vasospasm is the result of vasoconstriction or vascular endothelial swelling resulting in a narrowing of the intracranial arteries [4]. On the other hand, DCI is characterized by a new focal neurological deficit, a decrease in the level of consciousness, or radiographic evidence of new infarct [5]. Vasospasm is a radiographic diagnosis that does not necessarily correlate with functional outcome whereas DCI is directly related to morbidity and
%U http://www.hindawi.com/journals/nri/2013/256713/