Comparison of ischemic and hemorrhagic stroke in the thalamus

The thalamus plays a crucial role in brain function, and ischemic and hemorrhagic stroke in this region can lead to various neurological symptoms. This study aimed to identify differences in risk factors, functional outcomes, and neuroimaging markers between ischemic and hemorrhagic strokes of the thalamus.

Patients with acute thalamic stroke were classified into a thalamic intracerebral hemorrhage (ICH) and a thalamic infarction group (49 and 88 patients, respectively). The thalamic infarction group was further categorized into a good [modified Rankin Scale (mRS) score: 0-2] and a poor (mRS score: 3-6) outcome subgroup. Neuroimaging markers, clinical records, and laboratory results were compared.

Compared to the thalamic infarction group, the thalamic ICH group had a higher proportion of severe white matter hyperintensities (WMHs; Fazekas scale grade 3: 23.3% vs. 70.6%, P<0.004), a higher rate of high-grade microbleeds (MBs; 10.6% vs. 53.3%, P<0.001), and worse outcomes. Multivariate logistic regression analysis revealed that MBs were independently associated with thalamic ICH [adjusted odds ratio (aOR) =0.015, 95% confidence interval (CI): 0.001-0.266; P=0.004]. In the thalamic infarction group, patients with good outcomes had a lower proportion of severe WMH (Fazekas scale grade 3: 7.8% vs. 37.5%, P=0.012) than those with poor outcomes. Multivariate logistic regression analysis indicated that severe WMH (Fazekas scale grade 3: aOR =5.477, 95% CI: 1.113-26.957; P=0.036), diabetes mellitus (aOR =4.315; 95% CI: 1.121-16.609; P=0.033), and age (aOR =1.078 per year, 95% CI: 1.006-1.155; P=0.034) were independently associated with thalamic infarction outcomes. Lesion size was significantly correlated with National Institutes of Health Stroke Scale (NIHSS) scores (ß =0.775, R²=0.601, P<0.001), indicating that larger lesions were associated with more severe neurological deficits.

Patients with thalamic ICH had worse prognosis than those with thalamic infarction, with MBs being an independent thalamic ICH-related factor. High-grade WMHs were independently associated with poor outcomes in patients with thalamic infarctions. Therefore, small vessel disease-related imaging information can be used for stroke diagnosis and prognostic assessment.