Abstract TP71: Delayed Lesion on Diffusion-Weighted Image is Not Uncommon in Elderly and Severe Stroke-Suspected Patients

Abstract

Introduction: No lesion on admission DWI but delayed appearance in the follow-up DWI are not uncommon in acute stroke. Our aim is to investigate clinical features of patients with delayed-high intensity area (DHIA) on follow-up DWI. Methods: We enrolled 1) TIA patients and 2) clinically suspected stroke patients sustaining a neurological deficit over 24 hours without ischemic lesion on initial DWI. Follow-up DWI was performed in 7 days after admission. We divided into two groups as follows; DHIA group and no hyper-intense lesion on initial and second DWI (NHIA group). Univariate and multivariate logistic regression analysis were conducted on backgrounds, clinical courses including time from onset to MRI, symptom duration, and favorable outcome (mRS 0-1) in 3 months in both groups. Results: One hundred seventy-two cases were identified (male 68%, median age 66 yo, median NIHSS score 1, delayed-HIA group; 48 patients) between October 2012 and March 2019. DHIA group was older (72 yo vs 64 yo, p<0.001), higher NIHSS score on admission (1 vs 0, p=0.001), elevated serum BNP (42.5 pg/dL vs 15.6 pg/dL, p<0.001), D-Dimer (0.8 μg/mL vs 0.6 μg/mL, p=0.023). Then, favorable outcome was frequently observed in NHIA group (72% vs 88%, p=0.019). Time from onset to initial DWI of DHIA group was similar with those of NHIA group (130 min vs 148 min, p=0.142). Age and NIHSS score on admission were independent factors for DHIA (Age: OR 1.03, 95%CI 1.01-1.06, p=0.021, NIHSS on admission: OR 1.21, 95%CI 1.04-1.40, p=0.011). Conclusion: Follow-up DWI may play an important role of outcome biomarker in TIA and initially suspected stroke. Repeated MRI should be performed for elder and severe neurological deficits.