Diaschisis Revisited: Quantitative Evaluation of Thalamic Hypoperfusion in Anterior Circulation Stroke

Abstract Purpose Ipsilateral thalamic diaschisis (ITD) refers to the phenomenon of thalamic hypoperfusion or hypometabolism due to a distant cerebral injury. To further investigate the characteristics and spectrum of ITD, we analyzed quantitative measurements of thalamic hypoperfusion in acute anterior circulation stroke. Methods We selected consecutive patients with large-vessel occlusion (LVO) anterior circulation stroke and available CT perfusion (CTP) examination on admission who underwent endovascular thrombectomy. Thalamic perfusion parameters on CTP were tested between ipsi- and contralesional thalamus and ischemic territory. Values were compared with thresholds from CTP analysis software. Associations of thalamic perfusion parameters with acute imaging and clinical data were determined in uni- and multivariate logistic regression analyses. Results Ninety-nine patients were included. All perfusion parameters indicated significant non-ischemic hypoperfusion of the thalamus, not reaching the levels of ischemia in the middle cerebral artery territory due to LVO (all p Conclusions ITD in acute stroke is a non-binary phenomenon affected by lesion extent and involvement of the lentiform nucleus. We found uncorrected association of ITD with early clinical presentation, but no association with short- or long-term outcome was evident. Relevant misclassification of ITD by guideline-based CTP software was not indicated, which needs further dedicated testing.