Früh- und Differenzialdiagnose von Demenzen

Zusammenfassung

In den letzten Jahren ist es zu einer umfassenden Weiterentwicklung magnetresonanzbasierter bildgebender Verfahren gekommen. Dadurch stehen heute eine Reihe von Möglichkeiten zur anatomischen und funktionellen Charakterisierung des Gehirns zur Verfügung. Im Kompetenznetz Demenzen (KND) werden erstmalig die strukturelle MR-Tomographie (MRT) und die Protonen-MR-Spektroskopie (1H-MRS) in einem Multizenteransatz bezüglich ihrer möglichen Rolle in der Früh- und Differentialdiagnostik bei Demenzerkrankungen geprüft. Mit der strukturellen MRT werden hochauflösende anatomische Datensätze gewonnen. Die 1H-MRS liefert Informationen über die biochemische Komposition des Hirngewebes. Beide methodisch ausgereiften Verfahren wurden zu Beginn des Projektes auf ihre Interzenter-Reproduzierbarkeit geprüft und es zeigte sich hinsichtlich wesentlicher Zielparameter eine Interzentervariation, die eine zentrumsübergreifende Vergleichbarkeit gewährleistet. Die bisher gewonnenen Datensätze werden aufgrund der großen Stichprobe und der Verbindung mit anderen neuropsychologischen, biochemischen und genetischen Daten aus dem KND umfassende Aufschlüsse über die Rolle der MRT und der 1H-MRS in der Früh- und Differentialdiagnose von Demenzerkrankungen liefern.

Summary

Over the last years, MR techniques have been rapidly developed, which enables us now to visualize the brain’s anatomy with high resolution and to investigate various aspects of brain function. At present volumetric MRI and proton MR-spectroscopy (1H-MRS) have reached a technical level, which allows the application in a clinical context. In the German competence network on dementia, we designed a multicenter study, to assess the role of MRI and 1H-MRS in early recognition and differential diagnosis of dementia. At the beginning of the projects, the reproducability across centers was assessed and both techniques showed sufficient stability to be applied in a multicenter approach. The number of datasets acquired so far, in particular in combination with neuropsychology, CSF biochemistry and genetics, will allow a thorough definition of the strengths and weaknesses of both techniques in early and differential diagnosis of dementia.

Schlüsselwörter

Demenz - Magnetresonanz Tomographie - Magnetresonanz Spektroskopie - Hippokampus - Kompetenznetz Demenzen

Key words

Dementia - magnetic resonance imaging - magnetic resonance spectroscopy - hippocampus - Competence network on dementia

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