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Item does not contain fulltext, OBJECTIVE: Rescue therapies have been recommended for patients with angiographic vasospasm (aVSP) and delayed cerebral ischemia (DCI) following subarachnoid hemorrhage (SAH). However, there is little evidence from randomized clinical trials that these therapies are safe and effective. The primary aim of this study was to apply game theory-based methods in explainable machine learning (ML) and propensity score matching to determine if rescue therapy was associated with better 3-month outcomes following post-SAH aVSP and DCI. The authors also sought to use these explainable ML methods to identify patient populations that were more likely to receive rescue therapy and factors associated with better outcomes after rescue therapy. METHODS: Data for patients with aVSP or DCI after SAH were obtained from 8 clinical trials and 1 observational study in the Subarachnoid Hemorrhage International Trialists repository. Gradient boosting ML models were constructed for each patient to predict the probability of receiving rescue therapy and the 3-month Glasgow Outcome Scale (GOS) score. Favorable outcome was defined as a 3-month GOS score of 4 or 5. Shapley Additive Explanation (SHAP) values were calculated for each patient-derived model to quantify feature importance and interaction effects. Variables with high SHAP importance in predicting rescue therapy administration were used in a propensity score-matched analysis of rescue therapy and 3-month GOS scores. RESULTS: The authors identified 1532 patients with aVSP or DCI. Predictive, explainable ML models revealed that aneurysm characteristics and neurological complications, but not admission neurological scores, carried the highest relative importance rankings in predicting whether rescue therapy was administered. Younger age and absence of cerebral ischemia/infarction were invariably linked to better rescue outcomes, whereas the other important predictors of outcome varied by rescue type (interventional or noninterventional). In

Item does not contain fulltext, OBJECTIVE: Rescue therapies have been recommended for patients with angiographic vasospasm (aVSP) and delayed cerebral ischemia (DCI) following subarachnoid hemorrhage (SAH). However, there is little evidence from randomized clinical trials that these therapies are safe and effective. The primary aim of this study was to apply game theory-based methods in explainable machine learning (ML) and propensity score matching to determine if rescue therapy was associated with better 3-month outcomes following post-SAH aVSP and DCI. The authors also sought to use these explainable ML methods to identify patient populations that were more likely to receive rescue therapy and factors associated with better outcomes after rescue therapy. METHODS: Data for patients with aVSP or DCI after SAH were obtained from 8 clinical trials and 1 observational study in the Subarachnoid Hemorrhage International Trialists repository. Gradient boosting ML models were constructed for each patient to predict the probability of receiving rescue therapy and the 3-month Glasgow Outcome Scale (GOS) score. Favorable outcome was defined as a 3-month GOS score of 4 or 5. Shapley Additive Explanation (SHAP) values were calculated for each patient-derived model to quantify feature importance and interaction effects. Variables with high SHAP importance in predicting rescue therapy administration were used in a propensity score-matched analysis of rescue therapy and 3-month GOS scores. RESULTS: The authors identified 1532 patients with aVSP or DCI. Predictive, explainable ML models revealed that aneurysm characteristics and neurological complications, but not admission neurological scores, carried the highest relative importance rankings in predicting whether rescue therapy was administered. Younger age and absence of cerebral ischemia/infarction were invariably linked to better rescue outcomes, whereas the other important predictors of outcome varied by rescue type (interventional or noninterventional). In

Contains fulltext : 172587.pdf (publisher's version ) (Closed access), BACKGROUND AND PURPOSE: Poor-grade subarachnoid hemorrhage (SAH) (World Federation of Neurosurgical Societies grade 4 and 5) is associated with high mortality rates and unfavorable functional outcomes. We report a single-center cohort of poor-grade SAH patients, combined with a systematic review of studies reporting functional outcome in the poor-grade SAH population. METHODS: Data on a cohort of poor-grade SAH patients treated between 2009 and 2013 were retrospectively collected and combined with a systematic review (from inception to November 2015; PubMed, Embase). Two reviewers assessed the studies independently based on predefined inclusion criteria: consecutive poor-grade SAH, functional outcome measured at least 3 months after hemorrhage, and the report of patients who died before aneurysm treatment. RESULTS: The search yielded 329 publications, and 23 met our inclusion criteria with 2713 subjects enrolled from 1977 to 2014 in 10 countries (including 179 poor-grade patients from our cohort). Mortality rate was 60 % (1683 patients), of which 806 (29 %) died before and 877 (31 %) died after aneurysm treatment, respectively. Treatment was undertaken in 1775 patients (1775/2826-63 %): 1347 by surgical clipping (1347/1775-76 %) and 428 (428/1775-24 %) by endovascular methods. Outcome was favorable in 794 patients (28 %) and unfavorable in 1867 (66 %). When the studies were grouped into decades, favorable outcome increased from 13 % in the late 1970s to early 1980s to 35 % in the late 1980s to early 1990s, and remained unchanged thereafter. CONCLUSION: Although mortality remains high in poor-grade SAH patients, a favorable functional outcome can be achieved in approximately one-third of patients. The development of new diagnostic methods and implementation of therapeutic approaches were probably responsible for the decrease in mortality and improvement in the functional outcome from 1970 to the 1990s. The plateau in functional outcome seen thereafter might be explai

Contains fulltext : 172587.pdf (publisher's version ) (Closed access), BACKGROUND AND PURPOSE: Poor-grade subarachnoid hemorrhage (SAH) (World Federation of Neurosurgical Societies grade 4 and 5) is associated with high mortality rates and unfavorable functional outcomes. We report a single-center cohort of poor-grade SAH patients, combined with a systematic review of studies reporting functional outcome in the poor-grade SAH population. METHODS: Data on a cohort of poor-grade SAH patients treated between 2009 and 2013 were retrospectively collected and combined with a systematic review (from inception to November 2015; PubMed, Embase). Two reviewers assessed the studies independently based on predefined inclusion criteria: consecutive poor-grade SAH, functional outcome measured at least 3 months after hemorrhage, and the report of patients who died before aneurysm treatment. RESULTS: The search yielded 329 publications, and 23 met our inclusion criteria with 2713 subjects enrolled from 1977 to 2014 in 10 countries (including 179 poor-grade patients from our cohort). Mortality rate was 60 % (1683 patients), of which 806 (29 %) died before and 877 (31 %) died after aneurysm treatment, respectively. Treatment was undertaken in 1775 patients (1775/2826-63 %): 1347 by surgical clipping (1347/1775-76 %) and 428 (428/1775-24 %) by endovascular methods. Outcome was favorable in 794 patients (28 %) and unfavorable in 1867 (66 %). When the studies were grouped into decades, favorable outcome increased from 13 % in the late 1970s to early 1980s to 35 % in the late 1980s to early 1990s, and remained unchanged thereafter. CONCLUSION: Although mortality remains high in poor-grade SAH patients, a favorable functional outcome can be achieved in approximately one-third of patients. The development of new diagnostic methods and implementation of therapeutic approaches were probably responsible for the decrease in mortality and improvement in the functional outcome from 1970 to the 1990s. The plateau in functional outcome seen thereafter might be explai

Contains fulltext : 172587.pdf (publisher's version ) (Closed access), BACKGROUND AND PURPOSE: Poor-grade subarachnoid hemorrhage (SAH) (World Federation of Neurosurgical Societies grade 4 and 5) is associated with high mortality rates and unfavorable functional outcomes. We report a single-center cohort of poor-grade SAH patients, combined with a systematic review of studies reporting functional outcome in the poor-grade SAH population. METHODS: Data on a cohort of poor-grade SAH patients treated between 2009 and 2013 were retrospectively collected and combined with a systematic review (from inception to November 2015; PubMed, Embase). Two reviewers assessed the studies independently based on predefined inclusion criteria: consecutive poor-grade SAH, functional outcome measured at least 3 months after hemorrhage, and the report of patients who died before aneurysm treatment. RESULTS: The search yielded 329 publications, and 23 met our inclusion criteria with 2713 subjects enrolled from 1977 to 2014 in 10 countries (including 179 poor-grade patients from our cohort). Mortality rate was 60 % (1683 patients), of which 806 (29 %) died before and 877 (31 %) died after aneurysm treatment, respectively. Treatment was undertaken in 1775 patients (1775/2826-63 %): 1347 by surgical clipping (1347/1775-76 %) and 428 (428/1775-24 %) by endovascular methods. Outcome was favorable in 794 patients (28 %) and unfavorable in 1867 (66 %). When the studies were grouped into decades, favorable outcome increased from 13 % in the late 1970s to early 1980s to 35 % in the late 1980s to early 1990s, and remained unchanged thereafter. CONCLUSION: Although mortality remains high in poor-grade SAH patients, a favorable functional outcome can be achieved in approximately one-third of patients. The development of new diagnostic methods and implementation of therapeutic approaches were probably responsible for the decrease in mortality and improvement in the functional outcome from 1970 to the 1990s. The plateau in functional outcome seen thereafter might be explai

Item does not contain fulltext, BACKGROUND AND PURPOSE: Patients are classically at risk of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage. We validated a grading scale-the VASOGRADE-for prediction of DCI. METHODS: We used data of 3 phase II randomized clinical trials and a single hospital series to assess the relationship between the VASOGRADE and DCI. The VASOGRADE derived from previously published risk charts and consists of 3 categories: VASOGRADE-Green (modified Fisher scale 1 or 2 and World Federation of Neurosurgical Societies scale [WFNS] 1 or 2); VASOGRADE-Yellow (modified Fisher 3 or 4 and WFNS 1-3); and VASOGRADE-Red (WFNS 4 or 5, irrespective of modified Fisher grade). The relation between the VASOGRADE and DCI was assessed by logistic regression models. The predictive accuracy of the VASOGRADE was assessed by receiver operating characteristics curve and calibration plots. RESULTS: In a cohort of 746 patients, the VASOGRADE significantly predicted DCI (P<0.001). The VASOGRADE-Yellow had a tendency for increased risk for DCI (odds ratio [OR], 1.31; 95% CI, 0.77-2.23) when compared with VASOGRADE-Green; those with VASOGRADE-Red had a 3-fold higher risk of DCI (OR, 3.19; 95% CI, 2.07-4.50). Studies were not a significant confounding factor between the VASOGRADE and DCI. The VASOGRADE had an adequate discrimination for prediction of DCI (area under the receiver operating characteristics curve=0.63) and good calibration. CONCLUSIONS: The VASOGRADE results validated previously published risk charts in a large and diverse sample of subarachnoid hemorrhage patients, which allows DCI risk stratification on presentation after subarachnoid hemorrhage. It could help to select patients at high risk of DCI, as well as standardize treatment protocols and research studies.

Item does not contain fulltext, BACKGROUND AND PURPOSE: Patients are classically at risk of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage. We validated a grading scale-the VASOGRADE-for prediction of DCI. METHODS: We used data of 3 phase II randomized clinical trials and a single hospital series to assess the relationship between the VASOGRADE and DCI. The VASOGRADE derived from previously published risk charts and consists of 3 categories: VASOGRADE-Green (modified Fisher scale 1 or 2 and World Federation of Neurosurgical Societies scale [WFNS] 1 or 2); VASOGRADE-Yellow (modified Fisher 3 or 4 and WFNS 1-3); and VASOGRADE-Red (WFNS 4 or 5, irrespective of modified Fisher grade). The relation between the VASOGRADE and DCI was assessed by logistic regression models. The predictive accuracy of the VASOGRADE was assessed by receiver operating characteristics curve and calibration plots. RESULTS: In a cohort of 746 patients, the VASOGRADE significantly predicted DCI (P<0.001). The VASOGRADE-Yellow had a tendency for increased risk for DCI (odds ratio [OR], 1.31; 95% CI, 0.77-2.23) when compared with VASOGRADE-Green; those with VASOGRADE-Red had a 3-fold higher risk of DCI (OR, 3.19; 95% CI, 2.07-4.50). Studies were not a significant confounding factor between the VASOGRADE and DCI. The VASOGRADE had an adequate discrimination for prediction of DCI (area under the receiver operating characteristics curve=0.63) and good calibration. CONCLUSIONS: The VASOGRADE results validated previously published risk charts in a large and diverse sample of subarachnoid hemorrhage patients, which allows DCI risk stratification on presentation after subarachnoid hemorrhage. It could help to select patients at high risk of DCI, as well as standardize treatment protocols and research studies.

Item does not contain fulltext, BACKGROUND AND PURPOSE: Patients are classically at risk of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage. We validated a grading scale-the VASOGRADE-for prediction of DCI. METHODS: We used data of 3 phase II randomized clinical trials and a single hospital series to assess the relationship between the VASOGRADE and DCI. The VASOGRADE derived from previously published risk charts and consists of 3 categories: VASOGRADE-Green (modified Fisher scale 1 or 2 and World Federation of Neurosurgical Societies scale [WFNS] 1 or 2); VASOGRADE-Yellow (modified Fisher 3 or 4 and WFNS 1-3); and VASOGRADE-Red (WFNS 4 or 5, irrespective of modified Fisher grade). The relation between the VASOGRADE and DCI was assessed by logistic regression models. The predictive accuracy of the VASOGRADE was assessed by receiver operating characteristics curve and calibration plots. RESULTS: In a cohort of 746 patients, the VASOGRADE significantly predicted DCI (P<0.001). The VASOGRADE-Yellow had a tendency for increased risk for DCI (odds ratio [OR], 1.31; 95% CI, 0.77-2.23) when compared with VASOGRADE-Green; those with VASOGRADE-Red had a 3-fold higher risk of DCI (OR, 3.19; 95% CI, 2.07-4.50). Studies were not a significant confounding factor between the VASOGRADE and DCI. The VASOGRADE had an adequate discrimination for prediction of DCI (area under the receiver operating characteristics curve=0.63) and good calibration. CONCLUSIONS: The VASOGRADE results validated previously published risk charts in a large and diverse sample of subarachnoid hemorrhage patients, which allows DCI risk stratification on presentation after subarachnoid hemorrhage. It could help to select patients at high risk of DCI, as well as standardize treatment protocols and research studies.