Abstract WP172: Delayed Leukoencephalopathy Following Acute Ischemic Stroke

Background and Purpose: Delayed leukoencephalopathy (DL) following ischemic stroke with large vessel occlusion (LVO) is rarely reported and the pathophysiology is unclear. We aimed to investigate the incidence, clinical characteristics of DL following acute ischemic stroke. Methods: Consecutive ischemic stroke patients were screened. Inclusion criteria were: 1) onset to door time within 7 days; and 2) availability of initial and a second or more MRI after 14 days from onset with DWI, FLAIR, and MRA. We defined DL as newly detected diffuse hyperintensities restricted to the white matter on FLAIR mostly accompanied with partial DWI hyperintensities after 14 days from onset. First, we estimated the incidence of DL and whether a LVO would be a factor associated with DL following all the acute ischemic stroke. Second, limiting the patients with LVO, we evaluated the incidence and the factors associated with DL. Results: We screened 1,857 consecutive ischemic stroke patients. Of all, 792 with all the acute ischemic stroke (573 (72%) male, median age 67 years), and 183 with LVO (128 (70%) male, median age 67 years) were included in each analysis. DL were detected in 18 patients in all the acute ischemic stroke (2%), and 17 in patients with LVO (9%) (Figure). First, LVO was strongly associated with DL following all the acute ischemic stroke (OR 62.3, 95% CI 8.23 to 471, p <0.001). Second, limiting the patients with LVO, factors associated with DL were age/10 years (OR 1.64, 95% CI 1.08 to 2.47, p = 0.019), NIHSS score at admission (OR 1.06, 95% CI 1.01 to 1.11, p = 0.014), complete recanalization (OR unable to calculate due to 100% prevalence in DL group, p <0.001), and mechanical thrombectomy (OR 14.2, 95% CI 3.90 to 52.0 p <0.001). Conclusions: DL is not an uncommon phenomenon especially after LVO. Age, neurological severity, mechanical thrombectomy, and complete recanalization might be related to DL.