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Matthew E. Eagles, Michael K. Tso and R. Loch Macdonald

OBJECTIVE

Fluctuations in patient serum sodium levels are common after aneurysmal subarachnoid hemorrhage (aSAH), but their effect on patient outcome is not well described in the literature. The goal of this work was to better characterize the relationship between fluctuations in serum sodium levels, outcome, and the development of delayed cerebral ischemia (DCI) after aSAH.

METHODS

The authors performed a post hoc analysis of data from the Clazosentan to Overcome Neurological Ischemia and Infarction Occurring After Subarachnoid Hemorrhage (CONSCIOUS-1) trial. Patients had their serum sodium values recorded daily for 14 days post-aSAH. Average and average absolute daily differences in sodium levels were calculated for each patient based on 3 reference points: admission sodium levels, a normal sodium level (defined as 140 mmol/L), and the previous day’s sodium level. These variables were also calculated for the classic “vasospasm window” (days 3–12) post-aSAH. A stepwise logistic regression model, locally weighted scatterplot smoothing curves, and receiver operator characteristic curve analysis were used to evaluate the relationship between alterations in serum sodium levels and clinical outcome or the development of DCI after aSAH. Poor outcome was defined as a modified Rankin Scale (mRS) score of > 2 at 3 months.

RESULTS

The average daily difference in sodium values from baseline (p < 0.001), average daily difference from a normal sodium level (p < 0.001), average absolute daily difference from a normal sodium level (p = 0.015), and average absolute daily difference from the previous day’s sodium level (p = 0.017) were significant predictors of poor outcome in a stepwise multivariate regression model. There was a trend toward significance for average absolute daily difference from admission sodium levels during the vasospasm window as an independent predictor of DCI (p = 0.052). There was no difference in the predictive capacity for DCI when sodium fluctuations from post-aSAH days 1–14 were compared with those from the classic vasospasm window (days 3–12).

CONCLUSIONS

Fluctuations in serum sodium levels may play a role in clinical outcome and the development of DCI after aSAH. The timing of these fluctuations appears to have no significant effect on the development of DCI.

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Kunal Vakharia, Stephan A. Munich, Michael K. Tso, Muhammad Waqas and Elad I. Levy

Stent-assisted coiling offers a potential solution for coil embolization of broad-based aneurysms. Challenges associated with navigating a microcatheter beyond these aneurysms sometimes require looping the microcatheter within the aneurysm dome. Reducing microcatheter loops within domes can be difficult, and anchor techniques have been described, including balloon anchor, stent-retriever anchor, and stent anchor techniques. The authors present a patient requiring stent-assisted coiling of an anterior communicating artery aneurysm in whom a stent anchor technique was used to reduce a microcatheter loop within an aneurysm dome before coil embolization. Postembolization angiographic runs showed complete coil occlusion of the aneurysm with approximately 35% packing density.

The video can be found here: https://youtu.be/zHR1ZOArUro.

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Matthew E. Eagles, Maria F. Powell, Oliver G. S. Ayling, Michael K. Tso and R. Loch Macdonald

OBJECTIVE

Acute kidney injury (AKI) is associated with death in critically ill patients, but this complication has not been well characterized after aneurysmal subarachnoid hemorrhage (aSAH). The purpose of this study was to determine the incidence of AKI after aSAH and to identify risk factors for renal dysfunction. Secondary objectives were to examine what effect AKI has on patient mortality and functional outcome at 12 weeks post-aSAH.

METHODS

The authors performed a post hoc analysis of the Clazosentan to Overcome Neurological Ischemia and Infarction Occurring After Subarachnoid Hemorrhage (CONSCIOUS-1) trial data set (clinical trial registration no.: NCT00111085, https://clinicaltrials.gov). The primary outcome of interest was the development of AKI, which was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. Secondary outcomes of interest were death and a modified Rankin Scale score greater than 2 at 12 weeks post-aSAH. Propensity score matching was used to assess for a significant treatment effect related to clazosentan administration and AKI. Univariate analysis, locally weighted scatterplot smoothing (LOWESS) curves, and stepwise logistic regression models were used to evaluate for associations between baseline or disease-related characteristics and study outcomes.

RESULTS

One hundred fifty-six (38%) of the 413 patients enrolled in the CONSCIOUS-1 trial developed AKI during their ICU stay. A history of hypertension (p < 0.001) and the number of nephrotoxic medications administered (p = 0.029) were independent predictors of AKI on multivariate analysis. AKI was an independent predictor of death (p = 0.028) but not a poor functional outcome (p = 0.21) on multivariate testing. Unresolved renal dysfunction was the strongest independent predictor of death in this cohort (p < 0.001).

CONCLUSIONS

AKI is a common complication following aSAH. Patients with premorbid hypertension and those treated with nephrotoxic medications may be at greater risk for renal dysfunction. AKI appears to confer an increased probability of death after aSAH.

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Michael K. Tso, Myunghyun M. Lee, Chad G. Ball, William F. Morrish, Alim P. Mitha, Andrew W. Kirkpatrick and John H. Wong

OBJECTIVE

Blunt cerebrovascular injury (BCVI) occurs in approximately 1% of the blunt trauma population and may lead to stroke and death. Early vascular imaging in asymptomatic patients at high risk of having BCVI may lead to earlier diagnosis and possible stroke prevention. The objective of this study was to determine if the implementation of a formalized asymptomatic BCVI screening protocol with CT angiography (CTA) would lead to improved BCVI detection and stroke prevention.

METHODS

Patients with vascular imaging studies were identified from a prospective trauma registry at a single Level 1 trauma center between 2002 and 2008. Detection of BCVI and stroke rates were compared during the 3-year periods before and after implementation of a consensus-based asymptomatic BCVI screening protocol using CTA in 2005.

RESULTS

A total of 5480 patients with trauma were identified. The overall BCVI detection rate remained unchanged postprotocol compared with preprotocol (0.8% [24 of 3049 patients] vs 0.9% [23 of 2431 patients]; p = 0.53). However, postprotocol there was a trend toward a decreased risk of stroke secondary to BCVI on a trauma population basis (0.23% [7 of 3049 patients] vs 0.53% [13 of 2431 patients]; p = 0.06). Overall, 75% (35 of 47) of patients with BCVI were treated with antiplatelet agents, but no patient developed new or progressive intracranial hemorrhage despite 70% of these patients having concomitant traumatic brain injury.

CONCLUSIONS

The results of this study suggest that a CTA screening protocol for BCVI may be of clinical benefit with possible reduction in ischemic complications. The treatment of BCVI with antiplatelet agents appears to be safe.

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Aaron Hockley, Michael K. Tso, Mohammed A. Almekhlafi, Abhay K. Lodha, Robin Clegg, Jeremy Luntley, Muneer Eesa and John H. Wong

OBJECTIVE

Vein of Galen aneurysmal malformations (VGAMs) in infancy have a poor natural history if left untreated. Their high-flow nature can preclude safe and accurate therapeutic vessel occlusion and the risk of inadvertent pulmonary embolism is predominant. The authors describe the technique of rapid cardiac ventricular pacing for inducing transient hypotension to facilitate the controlled embolization of VGAMs.

METHODS

Initial transjugular venous access was obtained for placing temporary pacing leads for rapid cardiac ventricular pacing immediately prior to embolization. Definitive transarterial embolization procedures for the VGAMs were then performed in the same setting in which liquid embolic agents or coils were used.

RESULTS

Beginning in 2010, a total of five procedures were performed in three infants. Transvenous rapid cardiac ventricular pacing was successfully achieved to induce systemic transient flow arrest in all but two attempts, and facilitated partial embolization with n-butyl cyanoacrylate (n-BCA) and coils in all procedures. Ventricular fibrillation occurred twice in one patient and was successfully reversed with defibrillation on both occasions. One patient failed to improve and died from refractory heart failure. Two patients stabilized following staged embolization.

CONCLUSIONS

Rapid transvenous cardiac ventricular pacing can be considered to induce transient hypotension and facilitate controlled embolization in challenging high-flow VGAMs.

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Xiao Wu, David Durand, Vivek B. Kalra, Renu Liu and Ajay Malhotra

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Stephan A. Munich, Kunal Vakharia, Matthew J. McPheeters, Michael K. Tso, Adnan H. Siddiqui, Kenneth V. Snyder, Jason M. Davies and Elad I. Levy

OBJECTIVE

The mortality rates for stroke are decreasing, yet it remains a leading cause of disability and the principal neurological diagnosis in patients discharged to nursing homes. The societal and economic burdens of stroke are substantial, with the total annual health care costs of stroke expected to reach $240.7 billion by 2030. Mechanical thrombectomy has been shown to improve functional outcomes compared to medical therapy alone. Despite an incremental cost of $10,840 compared to medical therapy, the improvement in functional outcomes and decreased disability have contributed to the cost-effectiveness of the procedure. In this study the authors describe a physician-led device bundle purchase program implemented for the delivery of stroke care.

METHODS

The authors retrospectively reviewed the clinical and radiographic data and device-associated charges of 45 consecutive patients in whom a virtual “stroke bundle” model was used to purchase mechanical thrombectomy devices.

RESULTS

Use of the stroke bundle to purchase mechanical thrombectomy devices resulted in an average savings per case of $2900.93. Compared to the traditional model of charging for devices à la carte, this represented an average savings of 25.2% per case. The total amount of savings for these initial 45 cases was $130,542.00. Thrombolysis in Cerebral Infarction scale grade 2b or 3 recanalization occurred in 38 patients (84.4%) using these devices.

CONCLUSIONS

Purchasing devices through a bundled model resulted in substantial cost savings while maintaining the therapeutic efficacy of the procedure, further pushing the already beneficial long-term cost-benefit curve in favor of thrombectomy.

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Hamidreza Rajabzadeh-Oghaz, Muhammad Waqas, Sricharan S. Veeturi, Kunal Vakharia, Michael K. Tso, Kenneth V. Snyder, Jason M. Davies, Adnan H. Siddiqui, Elad I. Levy and Hui Meng

OBJECTIVE

Previous studies have found that ruptured intracranial aneurysms (RIAs) have distinct morphological and hemodynamic characteristics, including higher size ratio and oscillatory shear index and lower wall shear stress. Unruptured intracranial aneurysms (UIAs) that possess similar characteristics to RIAs may be at a higher risk of rupture than those UIAs that do not. The authors previously developed the Rupture Resemblance Score (RRS), a data-driven computer model that can objectively gauge the similarity of UIAs to RIAs in terms of morphology and hemodynamics. The authors aimed to explore the clinical utility of RRS in guiding the management of UIAs, especially for challenging cases such as small UIAs.

METHODS

Between September 2018 and June 2019, the authors retrospectively collected consecutive challenging cases of incidentally identified UIAs that were discussed during their weekly multidisciplinary neurovascular conference. From patient 3D digital subtraction angiography, they reconstructed the aneurysm geometry and performed computer-assisted 3D morphology analysis and computational fluid dynamics simulation. They calculated RRS for every UIA case and compared it against the treatment decision made at the neurovascular conference as well as the recommendation based on the unruptured intracranial aneurysm treatment score (UIATS).

RESULTS

Forty-seven patients with 79 UIAs, 90% of which were < 7 mm in size, were included in this study. The mean RRS (range 0.0–1.0) was 0.24 ± 0.31. At the conferences, treatment was endorsed for 45 of the UIAs (57%). These cases had significantly higher RRSs than the 34 cases suggested for observation (0.33 ± 0.34 vs 0.11 ± 0.19, p < 0.001). The UIATS-based recommendations were “observation” for 24 UIAs (30%), “treatment” for 21 UIAs (27%), and “not definitive” for 34 UIAs (43%). These “not definitive” cases were stratified by RRS based on similarity to RIAs.

CONCLUSIONS

Although not a rupture predictor, RRS is a data-driven model that gauges the similarity of UIAs to RIAs in terms of morphology and hemodynamics. In cases in which the UIATS-based recommendation is not definitive, RRS provides additional stratification to assist the identification of high-risk UIAs. The current study highlights the clinical utility of RRS in a real-world setting as an adjunctive tool for the management of UIAs.