Parenchymal Hematoma After Endovascular Thrombectomy Is Associated With Pretreatment Basal Ganglia Infarct Volume

Background and Purpose: Parenchymal hematomas (PHs) represent an important complication in ischemic stroke after endovascular thrombectomy (EVT), but the risk factors are incompletely understood. Neuroimaging data preintervention, such as infarct topography, may help elucidate predisposing factors and inform more nuanced patient care intra- and postprocedurally. Methods: Large vessel occlusion patients with pre-EVT MRI were included from a single quaternary center. Diffusion-weighted imaging (DWI) lesions underwent manual segmentation and registration onto a standard brain space for topographical mapping. The presence of PH postintervention was determined. Associations between infarct topography, clinical characteristics, and PH were evaluated. Results: A total of 165 patients (median age: 69; 56% female) were identified. Intravenous alteplase was administered to 52%, 70% achieved thrombolysis in cerebral infarction 2b-3 reperfusion, and 8% had PH postintervention. The preintervention DWI lesions were 48% (38%–60%) white matter, 23% (6%–47%) cortex, and 15% (4%–28%) basal ganglia. Basal ganglia infarct volume was independently associated with PH (adjusted odds ratio = 1.342, 95% confidence interval 1.002–1.797, p = 0.049), accounting for white matter and cortex infarct volume, among other key factors. Basal ganglia infarct volume was associated with susceptibility-weighted imaging vessel sign (beta_adjusted = 0.233, p = 0.006) and the National Institutes of Health Stroke Scale (beta_adjusted = 0.220, p = 0.012), controlling for other factors. Conclusions: Preintervention basal ganglia infarct volume may provide important insights into the risk of PH after intervention. Improved understanding of the biology of basal ganglia infarction and hemorrhagic transformation has implications for the management of patients undergoing EVT and may represent a future therapeutic target for neuroprotective strategies.