The “island sign” on diffusion-weighted imaging predicts early neurological deterioration in penetrating artery territory infarctions: a retrospective study

Abstract

Abstract Background Early neurological deterioration (END) sometimes occurs in patients with penetrating artery territory infarction (PATI) and leads to poor prognosis. In this study, we analyzed clinical and neuroimaging characteristics, especially the infarct patterns of PATI on diffusion-weighted imaging (DWI) to investigate whether the “island sign” pattern is associated with END.Methods One hundred thirteen patients with acute PATI admitted within 48 h after onset from May 2020 to July 2022 were enrolled in this study. They were divided into two groups according to infarct location: the territories of the lenticulostriate arteries (LSA) and paramedian pontine arteries (PPA). The patients in each group were further classified into the END and non-END groups according to whether they developed END. The PATI patterns were divided into with and without the “island sign” as observed on DWI. The clinical and neuroimaging characteristics of the patients were analyzed within the LSA and PPA groups.Results END was found in 17 patients (27.9%) in the LSA group and 20 patients (38.5%) in the PPA group. In the multivariate analysis, the independent predictors were the “island sign” (OR 4.88 95% CI 1.03–23.2 P = 0.045) and high initial National Institute of Health Stroke Scale (NIHSS) (OR 1.79 95% CI 1.08–2.98 P = 0.024) in the LSA group and lesions extending to the ventral pontine surface (OR 7.53 95% CI 1.75–32.37 P = 0.007) in the PPA group.Conclusions The predictive factors for END were different in the LSA and PPA groups. The “island sign” was particularly associated with END in the LSA group.