Parenchymal hyperdensity on C-arm CT images after endovascular therapy for acute ischaemic stroke predicts a poor prognosis

To investigate whether hyperdense areas (HDAs) observed after endovascular treatment on multisection computed tomography (CT) are related to outcome.Data on 82 patients with acute anterior circulation ischaemic stroke resulting from intracranial large artery occlusion were analysed retrospectively All patients underwent mechanical thrombectomy and/or emergency angioplasty, and partial or complete recanalisation was successfully achieved. C-arm CT was performed immediately after endovascular treatment for all patients. Clinical and radiological data were compared between patients with and those without HDA and between patients with good and those with poor outcomes.Compared with non-HDA patients, HDA patients were more likely to present with severe neurological deficits (admission National Institutes of Health Stroke Scale [NIHSS] score: 18 versus 16, p=0.037) and had a higher number of stent retriever passes performed (2.9±1.3 versus 1.4±1, p0.001), longer onset-to-presentation times (229±78 versus 171±90 minutes; p=0.002), longer onset-to-recanalisation times (418±94 versus 331±105 minutes; p0.001), and longer puncture-to-recanalisation times (103±47 versus 69±42 minutes; p=0.001). Fewer HDA patients had a good prognosis (35.7% versus 70%, p0.001). Multivariate analysis showed the presence of HDAs was an independent negative prognostic factor (OR=0.208; p=0.002).HDAs on C-arm CT appear to be common in patients with acute ischaemic stroke who underwent successful endovascular treatment. HDA presence suggests a poor prognosis despite successful reperfusion.