Abstracts

The phenomenon of total mismatch in acute stroke MRI

by Benjamin Hotter




Institution: Freie Universitt Berlin
Department:
Year: 2017
Posted: 02/01/2018
Record ID: 2152379
Full text PDF: http://edocs.fu-berlin.de/diss/receive/FUDISS_thesis_000000105852


Abstract

Introduction: We conducted a longitudinal Stroke-MRI study to evaluate the phenomenon of total mismatch: a rare state of missing proof of tissue infarction by diffusion-weighted MRI (DWI) while a more or less extensive perfusion deficit is depicted in perfusion MRI. We hypothesized that the extent of hypoperfusion as measured by the hypoperfusion intensity ratio (HIR), the severity of the clinical syndrome at admission and proof of artery occlusion would predict infarction on follow-up imaging. Methods: The 1000Plus stroke MRI study recruited patients presenting with an acute cerebrovascular event between September 2008 and October 2012. Subjects underwent multimodal MRI at admission and during early follow-up. We recorded basic demographic information and stroke characteristics. Stroke severity was measured using the National Institute of Health Stroke Scale (NIHSS). Criteria for inclusion in this sub-study were presence of total mismatch in the admission MRI and availability of a follow-up MRI. Results: Twenty-three patients were included in this analysis presenting at a median age of 70 (IQR 66-78). Ten subjects were female (43.5%). Proof of infarction was shown in 9 subjects (39.1%) during follow-up with a median infarction volume of 1.3 ml. Proof of infarction was associated with severity of stroke as measured by NIHSS at admission (p=0.026) and intensity of hypoperfusion as measured by HIR (p=0.015), but not with occlusion of the supplying artery on imaging. Clinical follow-up of patients with an infarction during follow-up was significantly worse as measured by last recorded NIHSS and modified Rankin scale. Conclusion: Cerebral infarctions are frequently found in the follow-up of total mismatch. Severity of stroke and extent of hypoperfusion, but not proof of artery occlusion are predictive of tissue fate. Einleitung: In dieser longitudinalen Schlaganfall-MRT-Studie untersuchten wir Patienten, die sich akut mit einem Total Mismatch also einer fehlenden Infarktdemarkation in diffusionsgewichtetem MRT (DWI), aber einem vorliegenden Perfusionsdefizit im MRT vorstellten. Wir postulierten, dass die Hypoperfusions-Intensitts-Ratio (HIR), der Schweregrad des Schlaganfalls, und ein darstellbarer Gefverschluss die Demarkierung eines Infarktes im Verlauf vorhersagen. Methodik: Patienten, die sich zwischen September 2008 und Oktober 2012 mit Verdacht auf TIA oder Schlaganfall in der Ersten Hilfe unseres Hauses vorstellten, wurden in die 1000Plus-Studie eingeschlossen. Im Rahmen dieser erfolgten eine akute multimodale MRT, sowie eine weitere MRT im Verlauf der nchsten Tage. An klinischen Daten wurden unter anderem demographische Parameter und Charakteristika des Schlaganfalls erhoben, wobei der Schweregrad anhand der National Institute of Health Stroke Scale (NIHSS) gemessen wurde. Einschlusskriterien fr diese Substudie waren das Vorliegen eines Total Mismatch bei der akuten Bildgebung und das Vorliegen eines MRTs im Verlauf.Ergebnisse: Wir identifizierten 23 Patienten mit Total Mismatch. Das