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C S Choi - One of the best experts on this subject based on the ideXlab platform.
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multidetector row ct angiography of cerebral Vasospasm after aneurysmal subarachnoid hemorrhage comparison of volume rendered images and digital subtraction angiography
American Journal of Neuroradiology, 2006Co-Authors: Daeyoung Yoon, C S Choi, Kwang Hyun Kim, B M ChoAbstract:BACKGROUND AND PURPOSE: Cerebral Vasospasm remains a major problem in patients recovering after surgical treatment of cerebral aneurysms. The purpose of this study was to evaluate cerebral Vasospasm at multidetector-row spiral CT angiography (MDCTA) compared with digital subtraction angiography (DSA) in patients with aneurysmal subarachnoid hemorrhages (SAHs). METHODS: Seventeen patients suspected of having Vasospasm on clinical findings underwent both postoperative MDCTA and DSA. MDCTA was analyzed by using volume-rendered images as well as axial images. A total of 251 arterial segments were analyzed for Vasospasm by using a 5-point grading system. The MDCTA results were then compared with findings on the corresponding DSA images. Sensitivity, specificity, and accuracy of MDCTA for detection of hemodynamically significant spasms were also calculated, with findings at DSA used as the reference standard. RESULTS: On DSA, 74 spasmatic segments were found among the 251 segments evaluated, and 40 segments with hemodynamically significant Vasospasms were present. The overall agreement between MDCTA and DSA was 95.2%. We had 12 (4.8%) cases of disagreement between MDCTA and DSA. In 11 segments, the degree of stenosis was overestimated at MDCTA. Overall accuracy, sensitivity and specificity of MDCTA in the detection of hemodynamically significant Vasospasm were 97.5%, 98.1%, and 98.0%, respectively, with positive and negative predictive values of 90.7% and 99.5%. CONCLUSION: MDCTA appears to be a reliable alternative imaging technique to DSA in the assessment of patients with cerebral Vasospasm after aneurysmal SAH.
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multidetector row ct angiography of cerebral Vasospasm after aneurysmal subarachnoid hemorrhage comparison of volume rendered images and digital subtraction angiography
American Journal of Neuroradiology, 2006Co-Authors: Daeyoung Yoon, C S ChoiAbstract:BACKGROUND AND PURPOSE: Cerebral Vasospasm remains a major problem in patients recovering after surgical treatment of cerebral aneurysms. The purpose of this study was to evaluate cerebral Vasospasm at multidetector-row spiral CT angiography (MDCTA) compared with digital subtraction angiography (DSA) in patients with aneurysmal subarachnoid hemorrhages (SAHs). METHODS: Seventeen patients suspected of having Vasospasm on clinical findings underwent both postoperative MDCTA and DSA. MDCTA was analyzed by using volume-rendered images as well as axial images. A total of 251 arterial segments were analyzed for Vasospasm by using a 5-point grading system. The MDCTA results were then compared with findings on the corresponding DSA images. Sensitivity, specificity, and accuracy of MDCTA for detection of hemodynamically significant spasms were also calculated, with findings at DSA used as the reference standard. RESULTS: On DSA, 74 spasmatic segments were found among the 251 segments evaluated, and 40 segments with hemodynamically significant Vasospasms were present. The overall agreement between MDCTA and DSA was 95.2%. We had 12 (4.8%) cases of disagreement between MDCTA and DSA. In 11 segments, the degree of stenosis was overestimated at MDCTA. Overall accuracy, sensitivity and specificity of MDCTA in the detection of hemodynamically significant Vasospasm were 97.5%, 98.1%, and 98.0%, respectively, with positive and negative predictive values of 90.7% and 99.5%. CONCLUSION: MDCTA appears to be a reliable alternative imaging technique to DSA in the assessment of patients with cerebral Vasospasm after aneurysmal SAH.
Daeyoung Yoon - One of the best experts on this subject based on the ideXlab platform.
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multidetector row ct angiography of cerebral Vasospasm after aneurysmal subarachnoid hemorrhage comparison of volume rendered images and digital subtraction angiography
American Journal of Neuroradiology, 2006Co-Authors: Daeyoung Yoon, C S Choi, Kwang Hyun Kim, B M ChoAbstract:BACKGROUND AND PURPOSE: Cerebral Vasospasm remains a major problem in patients recovering after surgical treatment of cerebral aneurysms. The purpose of this study was to evaluate cerebral Vasospasm at multidetector-row spiral CT angiography (MDCTA) compared with digital subtraction angiography (DSA) in patients with aneurysmal subarachnoid hemorrhages (SAHs). METHODS: Seventeen patients suspected of having Vasospasm on clinical findings underwent both postoperative MDCTA and DSA. MDCTA was analyzed by using volume-rendered images as well as axial images. A total of 251 arterial segments were analyzed for Vasospasm by using a 5-point grading system. The MDCTA results were then compared with findings on the corresponding DSA images. Sensitivity, specificity, and accuracy of MDCTA for detection of hemodynamically significant spasms were also calculated, with findings at DSA used as the reference standard. RESULTS: On DSA, 74 spasmatic segments were found among the 251 segments evaluated, and 40 segments with hemodynamically significant Vasospasms were present. The overall agreement between MDCTA and DSA was 95.2%. We had 12 (4.8%) cases of disagreement between MDCTA and DSA. In 11 segments, the degree of stenosis was overestimated at MDCTA. Overall accuracy, sensitivity and specificity of MDCTA in the detection of hemodynamically significant Vasospasm were 97.5%, 98.1%, and 98.0%, respectively, with positive and negative predictive values of 90.7% and 99.5%. CONCLUSION: MDCTA appears to be a reliable alternative imaging technique to DSA in the assessment of patients with cerebral Vasospasm after aneurysmal SAH.
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multidetector row ct angiography of cerebral Vasospasm after aneurysmal subarachnoid hemorrhage comparison of volume rendered images and digital subtraction angiography
American Journal of Neuroradiology, 2006Co-Authors: Daeyoung Yoon, C S ChoiAbstract:BACKGROUND AND PURPOSE: Cerebral Vasospasm remains a major problem in patients recovering after surgical treatment of cerebral aneurysms. The purpose of this study was to evaluate cerebral Vasospasm at multidetector-row spiral CT angiography (MDCTA) compared with digital subtraction angiography (DSA) in patients with aneurysmal subarachnoid hemorrhages (SAHs). METHODS: Seventeen patients suspected of having Vasospasm on clinical findings underwent both postoperative MDCTA and DSA. MDCTA was analyzed by using volume-rendered images as well as axial images. A total of 251 arterial segments were analyzed for Vasospasm by using a 5-point grading system. The MDCTA results were then compared with findings on the corresponding DSA images. Sensitivity, specificity, and accuracy of MDCTA for detection of hemodynamically significant spasms were also calculated, with findings at DSA used as the reference standard. RESULTS: On DSA, 74 spasmatic segments were found among the 251 segments evaluated, and 40 segments with hemodynamically significant Vasospasms were present. The overall agreement between MDCTA and DSA was 95.2%. We had 12 (4.8%) cases of disagreement between MDCTA and DSA. In 11 segments, the degree of stenosis was overestimated at MDCTA. Overall accuracy, sensitivity and specificity of MDCTA in the detection of hemodynamically significant Vasospasm were 97.5%, 98.1%, and 98.0%, respectively, with positive and negative predictive values of 90.7% and 99.5%. CONCLUSION: MDCTA appears to be a reliable alternative imaging technique to DSA in the assessment of patients with cerebral Vasospasm after aneurysmal SAH.
Loch R Macdonald - One of the best experts on this subject based on the ideXlab platform.
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effect of pharmaceutical treatment on Vasospasm delayed cerebral ischemia and clinical outcome in patients with aneurysmal subarachnoid hemorrhage a systematic review and meta analysis
Journal of Cerebral Blood Flow and Metabolism, 2011Co-Authors: Mervyn D I Vergouwen, Nima Etminan, Don Ilodigwe, Loch R MacdonaldAbstract:As it is often assumed that delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) is caused by Vasospasm, clinical trials often focus on prevention of Vasospasm with the aim to improve clinical outcome. However, the role of Vasospasm in the pathogenesis of DCI and clinical outcome is possibly smaller than previously assumed. We performed a systematic review and meta-analysis on all randomized, double-blind, placebo-controlled trials that studied the effect of pharmaceutical preventive strategies on Vasospasm, DCI, and clinical outcome in SAH patients to further investigate the relationship between Vasospasm and clinical outcome. Effect sizes were expressed in pooled risk ratio (RR) estimates with corresponding 95% confidence intervals (CI). A total of 14 studies randomizing 4,235 patients were included. Despite a reduction of Vasospasm (RR 0.80 (95% CI 0.70 to 0.92)), no statistically significant effect on poor outcome was observed (RR 0.93 (95% CI 0.85 to 1.03)). The variety of DCI definitions did not justify pooling the DCI data. We conclude that pharmaceutical treatments have significantly decreased the incidence of Vasospasm, but not of poor clinical outcome. This dissociation between Vasospasm and clinical outcome could result from methodological problems, sample size, insensitivity of clinical outcome measures, or from mechanisms other than Vasospasm that also contribute to poor outcome.
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temporal profile of potassium channel dysfunction in cerebrovascular smooth muscle after experimental subarachnoid haemorrhage
Neuroscience Letters, 2008Co-Authors: Babak S Jahromi, Yasuo Aihara, Jinglu Ai, Zhen Du Zhang, George W Weyer, Elena Nikitina, Reza Yassari, Khaled M Houamed, Loch R MacdonaldAbstract:Abstract The pathogenesis of cerebral Vasospasm after subarachnoid haemorrhage (SAH) involves sustained contraction of arterial smooth muscle cells that is maximal 6–8 days after SAH. We reported that function of voltage-gated K + (K V ) channels was significantly decreased during Vasospasm 7 days after SAH in dogs. Since arterial constriction is regulated by membrane potential that in turn is determined predominately by K + conductance, the compromised K + channel dysfunction may cause Vasospasm. Additional support for this hypothesis would be demonstration that K + channel dysfunction is temporally coincident with Vasospasm. To test this hypothesis, SAH was created using the double haemorrhage model in dogs and smooth muscle cells from the basilar artery, which develops Vasospasm, were isolated 4 days (early Vasospasm), 7 days (during Vasospasm) and 21 days (after Vasospasm) after SAH and studied using patch-clamp electrophysiology. We investigated the two main K + channels (K V and large-conductance voltage/Ca 2+ -activated (K Ca ) channels). Electrophysiologic function of K Ca channels was preserved at all times after SAH. In contrast, function of K V channels was significantly decreased at all times after SAH. The decrease in cell size and degree of K V channel dysfunction was maximal 7 days after SAH. The results suggest that K V channel dysfunction either only partially contributes to Vasospasm after SAH or that compensatory mechanisms develop that lead to resolution of Vasospasm before K V channels recover their function.
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prediction of symptomatic Vasospasm after subarachnoid hemorrhage the modified fisher scale
Neurosurgery, 2006Co-Authors: Jennifer A Frontera, Loch R Macdonald, Jan Claassen, Michael J Schmidt, Katja E Wartenberg, Richard Temes, Sander E Connolly, Stephan A MayerAbstract:Objective We developed a modification of the Fisher computed tomographic rating scale and compared it with the original Fisher scale to determine which scale best predicts symptomatic Vasospasm after subarachnoid hemorrhage. Methods We analyzed data from 1355 subarachnoid hemorrhage patients in the placebo arm of four randomized, double-blind, placebo-controlled studies of tirilazad. Modified Fisher computed tomographic grades were calculated on the basis of the presence of cisternal blood and intraventricular hemorrhage. Crude odds ratios (OR) reflecting the risk of developing symptomatic Vasospasm were calculated for each scale level, and adjusted ORs expressing the incremental risk were calculated after controlling for known predictors of Vasospasm. Results Of 1355 patients, 451 (33%) developed symptomatic Vasospasm. For the modified Fisher scale, compared with Grade 0 to 1 patients, the crude OR for Vasospasm was 1.6 (95% confidence interval [CI], 1.0-2.5) for Grade 2, 1.6 (95% CI, 1.1-2.2) for Grade 3, and 2.2 (95% CI, 1.6-3.1) for Grade 4. For the original Fisher scale, referenced to Grade 1, the OR for Vasospasm was 1.3 (95% CI, 0.7-2.2) for Grade 2, 2.2 (95% CI, 1.4-3.5) for Grade 3, and 1.7 (95% CI, 1.0-3.0) for Grade 4. Early angiographic Vasospasm, history of hypertension, neurological grade, and elevated admission mean arterial pressure were identified as risk factors for symptomatic Vasospasm. After adjusting for these variables, the modified Fisher scale remained a significant predictor of Vasospasm (adjusted OR, 1.28; 95% CI, 1.06-1.54), whereas the original Fisher scale was not. Conclusion The modified Fisher scale, which accounts for thick cisternal and ventricular blood, predicts symptomatic Vasospasm after subarachnoid hemorrhage more accurately than original Fisher scale.
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papaverine sensitive Vasospasm and arterial contractility and compliance after subarachnoid hemorrhage in dogs
Neurosurgery, 1995Co-Authors: Loch R Macdonald, Bogdan Sima, John H. Zhang, Lydia JohnsAbstract:: This study examined the relationship between papaverine-sensitive and -insensitive components of Vasospasm, arterial contractility and compliance, and time after subarachnoid hemorrhage (SAH) in dogs. Eighteen dogs underwent angiography and then two intracisternal injections of blood. Angiography was repeated 4 (n = 5), 7 (n = 4), 10 (n = 4), or 14 (n = 5) days later. Papaverine, 100 to 200 mg, was infused into the basilar artery, and angiography was repeated. Four additional dogs had cerebral angiography only and served as controls. The basilar arteries were removed and studied pharmacologically. Significant Vasospasm of the basilar artery was observed each time after SAH. Papaverine significantly reversed Vasospasm at 4 and 7 days (88 +/- 6% and 63 +/- 11% of Vasospasm reversed; analysis of variance, P < 0.05). The papaverine-insensitive component of Vasospasm increased significantly with increasing time after SAH and with increasing severity of Vasospasm. Arterial contractility and compliance decreased significantly with increasing time after SAH and were significantly related to the degree of papaverine-insensitive Vasospasm but not to the severity of Vasospasm. In conclusion, the majority of Vasospasm early after SAH in dogs was caused by reversible vasoconstriction. The ability of papaverine to reverse Vasospasm depended on the time after SAH and on the severity of Vasospasm, a finding that may be important to the use of papaverine in humans. The pathological and biochemical basis for the association between papaverine-insensitive Vasospasm and reduced arterial wall contractility and compliance remains to be determined.
Chirag D Gandhi - One of the best experts on this subject based on the ideXlab platform.
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isolated intraventricular hemorrhage associated with cerebral Vasospasm and delayed cerebral ischemia following arteriovenous malformation rupture
Interventional Neurology, 2018Co-Authors: Krishna Amuluru, Fawaz Almufti, Charles E Romero, Chirag D GandhiAbstract:Background Although it is well characterized in aneurysmal subarachnoid hemorrhage, Vasospasm is exceedingly rare following cerebral arteriovenous malformation (AVM) rupture. Subsequently, this complication is poorly characterized with regard to delayed cerebral ischemia (DCI). We review cases of ruptured AVM to assess the frequency and severity of Vasospasm on cerebral angiography, and DCI. Summary We reviewed our institutional database of acute intracranial hemorrhages between 2005 and 2014. We identified patients with cerebral AVM rupture and evidence of Vasospasm, which was confirmed with digital subtraction angiography (DSA). Cerebral angiograms were evaluated by 2 blinded neurointerventionalists for Vasospasm. Statistical analyses were conducted on the angiographic results and variables of interest to determine predictors and associations of Vasospasm and DCI. Thirty-six patients with acute intracranial hemorrhage due to ruptured cerebral AVM subsequently underwent cerebral angiography. The interrater reliability for Vasospasm was 0.81. The incidence of Vasospasm was 13.9% and the incidence of subsequent DCI was 11.1%. A significant relationship existed between isolated intraventricular hemorrhage and Vasospasm (p = 0.001) and subsequent DCI (p = 0.006). Radiographic Vasospasm was associated with DCI in 80% of the patients (p < 0.0001). No statistical significance existed between subarachnoid hemorrhage and the development of Vasospasm or DCI (p = 1.000 and p = 0.626, respectively). All differences were significant at a 99% level of significance. Key Message In cases of ruptured AVM, isolated intraventricular hemorrhage appears to be an independent risk factor for Vasospasm and DCI. Vasospasm must be considered during late neurological deterioration following AVM hemorrhage, especially in the setting of isolated intraventricular hemorrhage.
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e 094 isolated intraventricular hemorrhage associated with cerebral Vasospasm and delayed cerebral ischemia following arteriovenous malformation rupture
Journal of NeuroInterventional Surgery, 2018Co-Authors: Fawaz Almufti, Krishna Amuluru, Charles E Romero, Neil Majmundar, Mohammad Elghanem, V Patel, Chirag D GandhiAbstract:Introduction Although well characterized in aneurysmal subarachnoid hemorrhage, Vasospasm is exceedingly rare following cerebral arteriovenous malformation (AVM) rupture. Subsequently, this complication is poorly characterized in regards to delayed cerebral ischemia (DCI). We review cases of ruptured AVMs to assess the frequency and severity of Vasospasm on cerebral angiography, and DCI. Methods We reviewed our institutional database of acute intracranial hemorrhages between 2005 and 2014, and identified patients with cerebral AVM rupture and evidence of Vasospasm confirmed with digital subtraction angiography (DSA) were included. Cerebral angiograms were evaluated by 2 blinded neurointerventionalists for Vasospasm. Statistical analyses were conducted on the angiographic results and variables of interest to determine predictors and associations of Vasospasm and DCI. Results Thirty-six patients with acute intracranial hemorrhage due to ruptured cerebral AVMs subsequently underwent cerebral angiography. The inter-rater reliability for Vasospasm was 0.81. The incidence of Vasospasm was 13.9% and the incidence of subsequent DCI was 11.1%. A significant relationship existed between isolated intraventricular hemorrhage and Vasospasm (p=0.001) and subsequent DCI (p=0.006). Intraparenchymal hemorrhage was also associated with Vasospasm (p=0.003) and subsequent DCI (p=0.001). Radiographic Vasospasm was associated with DCI in 80% of patients (p Conclusion In cases of ruptured AVMs, isolated intraventricular hemorrhage and intraparenchymal hemorrhage appear to be independent risk factors for Vasospasm and DCI. Vasospasm must be considered during late neurological deterioration following AVM hemorrhage, especially in the setting of isolated IVH. Disclosures F. Al-Mufti: None. K. Amuluru: None. N. Majmundar: None. M. El-Ghanem: None. V. Patel: None. C. Romero: None. C. Gandhi: None.
B M Cho - One of the best experts on this subject based on the ideXlab platform.
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multidetector row ct angiography of cerebral Vasospasm after aneurysmal subarachnoid hemorrhage comparison of volume rendered images and digital subtraction angiography
American Journal of Neuroradiology, 2006Co-Authors: Daeyoung Yoon, C S Choi, Kwang Hyun Kim, B M ChoAbstract:BACKGROUND AND PURPOSE: Cerebral Vasospasm remains a major problem in patients recovering after surgical treatment of cerebral aneurysms. The purpose of this study was to evaluate cerebral Vasospasm at multidetector-row spiral CT angiography (MDCTA) compared with digital subtraction angiography (DSA) in patients with aneurysmal subarachnoid hemorrhages (SAHs). METHODS: Seventeen patients suspected of having Vasospasm on clinical findings underwent both postoperative MDCTA and DSA. MDCTA was analyzed by using volume-rendered images as well as axial images. A total of 251 arterial segments were analyzed for Vasospasm by using a 5-point grading system. The MDCTA results were then compared with findings on the corresponding DSA images. Sensitivity, specificity, and accuracy of MDCTA for detection of hemodynamically significant spasms were also calculated, with findings at DSA used as the reference standard. RESULTS: On DSA, 74 spasmatic segments were found among the 251 segments evaluated, and 40 segments with hemodynamically significant Vasospasms were present. The overall agreement between MDCTA and DSA was 95.2%. We had 12 (4.8%) cases of disagreement between MDCTA and DSA. In 11 segments, the degree of stenosis was overestimated at MDCTA. Overall accuracy, sensitivity and specificity of MDCTA in the detection of hemodynamically significant Vasospasm were 97.5%, 98.1%, and 98.0%, respectively, with positive and negative predictive values of 90.7% and 99.5%. CONCLUSION: MDCTA appears to be a reliable alternative imaging technique to DSA in the assessment of patients with cerebral Vasospasm after aneurysmal SAH.