Predicting Delayed Cerebral Ischemia with Quantified Aneurysmal Subarachnoid Blood Volume

Delayed cerebral ischemia (DCI) is at presentation a diagnosis per exclusionem, and can only be confirmed with follow-up imaging. For treatment of DCI a diagnostic tool is needed. We performed a systematic review to evaluate the value of CT perfusion (CTP) in the prediction and diagnosis of DCI. We searched PubMed, Embase, and Cochrane databases to identify studies on the relationship between CTP and DCI. Eleven studies totaling 570 patients were included. On admission, cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and time-to-peak (TTP) did not differ between patients who did and did not develop DCI. In the DCI time-window (4 to 14 days after subarachnoid hemorrhage (SAH)), DCI was associated with a decreased CBF (pooled mean difference −11.9 mL/100 g per minute (95% confidence interval (CI): −15.2 to −8.6)) and an increased MTT (pooled mean difference 1.5 seconds (0.9–2.2)). Cerebral blood volume did not differ and TTP was rarely reported. Perfusion thresholds reported in studies were comparable, although the corresponding test characteristics were moderate and differed between studies. We conclude that CTP can be used in the diagnosis but not in the prediction of DCI. A need exists to standardize the method for measuring perfusion with CTP after SAH, and optimize and validate perfusion thresholds.

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Association of Automatically Quantified Total Blood Volume after Aneurysmal Subarachnoid Hemorrhage with Delayed Cerebral Ischemia

American Journal of Neuroradiology ◽

10.3174/ajnr.a4771 ◽

2016 ◽

Vol 37 (9) ◽

pp. 1588-1593 ◽

Cited By ~ 10

Author(s):

I.A. Zijlstra ◽

C.S. Gathier ◽

A.M. Boers ◽

H.A. Marquering ◽

A.J. Slooter ◽

...

Keyword(s):

Subarachnoid Hemorrhage ◽

Cerebral Ischemia ◽

Blood Volume ◽

Aneurysmal Subarachnoid Hemorrhage ◽

Delayed Cerebral Ischemia ◽

Total Blood Volume ◽

Total Blood

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Computed Tomographic Perfusion in the Management of Aneurysmal Subarachnoid Hemorrhage: New Application of an Existent Technique

Neurosurgery ◽

10.1227/01.neu.0000148902.61943.df ◽

2005 ◽

Vol 56 (2) ◽

pp. 304-317 ◽

Cited By ~ 45

Author(s):

Mark R. Harrigan ◽

Christopher R. Magnano ◽

Lee R. Guterman ◽

L Nelson Hopkins

Keyword(s):

Cerebral Ischemia ◽

Blood Volume ◽

Perfusion Imaging ◽

Cerebral Blood Volume ◽

Ct Perfusion ◽

Aneurysmal Subarachnoid Hemorrhage ◽

Delayed Cerebral Ischemia ◽

Computed Tomographic ◽

Time To Peak ◽

Ct Perfusion Imaging

Abstract OBJECTIVE: Cerebral blood flow (CBF) alterations are common after aneurysmal subarachnoid hemorrhage (SAH). Treatment of delayed cerebral ischemia in this setting depends on timely and accurate diagnosis. Techniques to measure cerebral blood flow are useful and important. Computed tomographic (CT) perfusion imaging is a technique for the measurement of CBF, cerebral blood volume, and time to peak. It is a fast and inexpensive brain imaging modality that offers promise in the management of patients with SAH. METHODS: CT perfusion imaging was performed in 10 patients with aneurysmal SAH when neurological changes raised suspicions of cerebral ischemia. Quantitative values for CBF, cerebral blood volume, and time to peak were obtained in each study. The case history, CT perfusion results, and an analysis of how patient management was influenced are presented for each patient. RESULTS: A total of 17 CT perfusion studies were performed. Five studies showed evidence of cerebral ischemia, leading to endovascular treatment of vasospasm. Eight studies excluded cerebral ischemia, and two studies identified cerebral hyperemia, resulting in adjustments in hyperdynamic therapy. CT perfusion was used to help predict a poor prognosis and withhold aggressive intervention in two patients with poor Hunt and Hess grades. Time-to-peak values identified regions of cerebral ischemia more readily than CBF or cerebral blood volume values. CONCLUSION: CT perfusion imaging can be used to identify patients with delayed cerebral ischemia after SAH and to guide medical and endovascular therapy. The findings can lead to alterations in patient management.

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Thromboembolism and Delayed Cerebral Ischemia after Subarachnoid Hemorrhage: An Autopsy Study

Neurosurgery ◽

10.1227/01.neu.0000227519.27569.45 ◽

2006 ◽

Vol 59 (4) ◽

pp. 781-788 ◽

Cited By ~ 100

Author(s):

Sherman C. Stein ◽

Kevin D. Browne ◽

Xiao-Han Chen ◽

Douglas H. Smith ◽

David I. Graham

Keyword(s):

Subarachnoid Hemorrhage ◽

Cerebral Ischemia ◽

Delayed Cerebral Ischemia ◽

Autopsy Study ◽

Significant Difference ◽

Cast Doubt ◽

Clot Burden ◽

The Mean ◽

Subarachnoid Blood ◽

Hematoxylin Eosin

Abstract OBJECTIVE: Recent findings have cast doubt on vasospasm as the sole cause of delayed cerebral ischemia after subarachnoid hemorrhage. METHODS: We reviewed the medical records of 29 patients who died after subarachnoid hemorrhage. Brain sections were taken from the insula, cingulate gyrus, and hippocampus. Adjacent sections were stained with hematoxylin-eosin and immunostained for thromboemboli. The density (burden) of the latter was calculated blindly and correlated with evidence for ischemia and with the amount of subarachnoid blood. RESULTS: There is a strong correlation between microclot burden and delayed cerebral ischemia. Patients with clinical or radiological evidence of delayed ischemia had mean microclot burdens of 10.0/cm2 (standard deviation [SD], ±6.6); those without had mean burdens of 2.8 (SD, ±2.6), a highly significant difference (P = 0.002). There is also significant association (P = 0.001) between microclot burden and histological evidence of ischemia, with the mean burdens being 10.9 in sections exhibiting severe ischemia and 4.1 in those in which ischemia was absent. Microclot burden is high in patients who died within 2 days of hemorrhage, decreasing on Days 3 and 4. In delayed ischemia, the numbers rise again late in the first week and remain high until after the second week. In contrast, the average clot burden is low in patients dying without developing delayed ischemia. The amount of blood on an individual slide influenced the microclot burden on that slide to a highly significant extent (P < 0.001). CONCLUSION: Thromboembolism after subarachnoid hemorrhage may contribute to delayed cerebral ischemia, which parallels that caused by vasospasm. The pathogenesis of thromboembolism is discussed.

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