Can resting state fMRI help differentiate between Vascular and Alzheimer's dementia?

Question: Can a Resting state (RS) fMRI be performed on a 1.5T MRI scanner ? Can it identify various types of dementias? (e.g. vascular dementia, Alzheimer”s dementia). Is it feasible to use it in a clinical setting ? Method: In a cohort of patients with cognitive impairment due to known cause, structural and functional images were acquired on a dedicated MRI scanner with 1.5T and an 8 channel parallel imaging coil. In addition, patients underwent a battery of cognitive tests. High resolution T1 weighted 3D FSPGR images were added to the routine dementia protocol in order to obtain anatomical images for core registration of the fMRI data. fMRI images were then analysed using proprietary software by evaluating spontaneous low frequency fluctuations, functional connectivity and interactions between distant brain regions. In addition, a cognitive test battery was performed. Results: In Patients with AD we could confirm that the default mode network (DMN) was particularly affected, which is characteristic for the disease. Additionally we found connectivity and network integrity diminished in the elderly and that this was especially pronounced in AD.
There was also a correlation between functional structures and performance on cognitive assessments. Interhemispheric synchronization of neuronal signaling was observed in regard to disease severity. Conclusion: We were able to demonstrate disease specific findings in AD. Further collection of data may in the future identify characteristic features for other types of dementia.