Infarct growth velocity predicts early neurological outcomes in single subcortical infarction

In single subcortical infarction (SSI), changes in lesion size are a major determinant of early neurological deterioration. We evaluated the association between END and infarct growth velocity (IGV) in patients with SSI. We included consecutive patients with SSI who underwent MRI within 24 h of symptom onset between 2010 and 2020. END was defined as an increase of ≥ 2 in the total National Institutes of Health Stroke Scale (NIHSS) score or ≥ 1 in the motor NIHSS score. IGV was calculated using the following formula: IGV (mL/h) = diffusion-weighted imaging volume (mL)/time to MRI (h). A total of 604 patients with SSI were evaluated. Multivariable logistic regression analysis showed that IGV remained significant after adjusting for confounders (aOR = 1.34, 95% CI 1.12-1.61). In a subgroup analysis based on the type of SSI, only patients with distal SSI showed an association between IGV and END (aOR = 1.64, 95% CI 1.24-2.16). In patients with proximal SSI, IGV did not show any statistical association with END. In conclusion, IGV was positively associated with END in patients with SSI. IGV should be interpreted differently in clinical settings depending on the location of the SSI lesion.