Dokument

Zusammenfassung:
Einführung Die idiopathische REM Schlaf Verhaltensstörung (iRBD) - eine Parasomnie, die durch das Ausleben der Träume gekennzeichnet ist - ist ein Risikofaktor für die Entwicklung des Morbus Parkinson (MP) und anderer α-Synucleinopathien. Es wird vermutet, dass die Pathophysiologie der Erkrankung in einer Dysfunktion der Hirnstammkerne liegt, die den REM Schlaf regulieren. Material und Methoden Mit dem Diffusion Tensor Imaging (DTI) kann die Mikrostruktur und die Integrität des Hirngewebes in vivo beurteilt werden. Wir untersuchten, ob mit DTI mikrostruktutrelle Veränderungen bei Patienten mit iRBD - im Vergleich mit alters-gematchten Kontrollen - entdeckt werden können. Diese Veränderungen könnten ein potentieller Marker für Veränderungen in Verbindung mit einem präklinischen MP sein. Patienten mit iRBD (n=12) und alters-gematchte, gesunde Kontrollen wurden in einem Routine 1.5 T MRT Scanner untersucht. Dabei wurden Ganzkopfscans der Fraktionalen Anisotropie (FA), der Axialen Diffusität (AD), ein potentieller Marker für axonale Schädigung, und der radialen Diffusität (RD), ein potentieller Marker für Myelinschädigung, ohne a-priori-Hypothese mit Hilfe der Tract Based Spatial Statistics (TBSS), einer neuen Technik um Artefakte und Registrierungsfehler zu minimieren, untersucht. Ergebnisse In der Gruppenanalyse fanden wir signifikante mikrostrukturelle Veränderungen des Hirngewebes der iRBD Patienten in der weißen Substanz des Hirnstammes (p<0.0001), der olfaktorischen Region, dem Temporallappen, der Fornix, der Capsula Interna, der Corona Radiata, dem rechten visuellen Trakt und der rechten Substantia Nigra. Diskussion Die mikrostrukturellen Veränderungen wurden in Regionen identifiziert, die dafür bekannt sind, entweder an der Regulation des REM Schlafs beteiligt zu sein und/oder neurodegenerative Pathologien in frühen Stadien der iRBD und/oder des MP zu zeigen. Die Ergebnisse dieser Studie zeigen, das mikrostrukturelle Veränderungen in Verbindung mit dem iRBD, mittels DTI, einer weit verbreiteten MRT Technologie, nachgewiesen werden können.

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