MRT-basierte Diagnostik von Demenzen

Zusammenfassung

Die strukturelle Magnetresonanztomografie (MRT) spielt für die Abklärung von demenziellen Syndromen sowohl beim Ausschluss potenziell behandelbarer Ursachen als auch für die Differenzialdiagnose spezifischer Formen der Demenz eine zunehmende Rolle. T1-gewichtete Sequenzen erlauben eine gute Beurteilung der Atrophie, während FLAIR und T2*-Wichtung Aussagen zu Veränderungen der weißen Substanz und zu Mikroblutungen erlauben. Im Kontext klinischer Studien im Bereich der Alzheimer-Demenz (AD) dient die MRT als Verlaufsparameter mit enger Korrelation zu krankheitsspezifischen neuropathologischen Veränderungen und kognitiven Einschränkungen. Im Rahmen klinischer Studien dient sie zudem der Risikoabschätzung für die Entwicklung einer Demenz bei Patienten mit leichter kognitiver Störung (LKS). Eine Reihe vergleichsweise neuer MRT-Sequenzen, wie funktionelle MRT, diffusionsgewichteten Sequenzen und Arterial Spin Labelling werden auf ihren Nutzen für die klinische Routine hin geprüft.

Summary

Structural magnetic resonance imaging (MRI) is gaining relevance for the diagnosis of dementia syndromes. It helps to identify potentially curable causes but also provides positive predictive value to the diagnosis of specific types of dementia. T1-weighted sequences aid in the assessment of atrophy while FLAIR and T2*-weighing provides information on white matter hyperintensities and microbleeds. In context of clinical studies of Alzheimer’s Disease (AD), MRI has proven to be a valuable marker of disease progression. MRI is highly correlated with the underlying pathophysiology of AD but also with the level of cognitive impairment. Functional MRI, diffusion weighted sequences and Arterial Spin Labelling are among those currently being assessed for a future integration into clinical routine given that they are complementary to standard sequences.

Schlüsselwörter

Demenz - MRT - neue MRT-Sequenzen

Keywords

Dementia - MRI - new MR sequences

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