Metabolic network activity and atrophy patterns in patients with parkinsonian disorders

The differential diagnosis of patients with parkinsonian disorders solely based
on clinical criteria can be difficult, but is particularly important because
they differ in progression, prognosis and treatment responses. A new developed
FDG PET strategy uses multivariate analysis to identify disease-related spatial
covariance patterns. This metabolic network approach is useful to characterise
the unique metabolic patterns in neurodegenerative disorders. It has been
suggested only by one research group, so it is very important to test the
validity of described method in order to create a definite disease related
pattern. Furthermore, published literature about metabolic network activity in
neurodegenerative disorders did not include the precise degree of microscopic
tissue degeneration or atrophy using modern MRI techniques. Voxel based
morphometry (VBM), is a technique that objectively localizes focal grey and
white matter atrophy throughout the entire brain. Diffusion Tensor MRI (DT MRI)
is a quantitative technique that allows microscopic tissue abnormalities to be
assessed non-invasively. It will be necessary to include patterns of atrophy
and tissue degeneration in order to create a reliable and early disease related
pattern. These methods combined can be used to identify an early and specific
diagnosis in individual patients.

Databases with multimodal brain imaging data (FDG-PET, VBM, DTI) will be
created. From these data image features and network patterns will be extracted,
to be used to create a supervised classification method for associating brain
patterns to various stages of neurodegenerative diseases.

In this observational case control study, 15 patients with idiopathic
Parkinson*s disease (IPD) and with 15 patients multiple system atrophy (MSA) as
well as 15 gender- and age matched healthy volunteers will be included. All
subjects will undergo neurological- and neuropsychological examination as well
as 1 FDG PET scan and 1 MRI scan according to protocol.

The risks and burden associated with participation are considered negligible
and minimal the since there is great experience in normal diagnostic work up
with these PET and MRI investigations and significant side effects are not
mentioned. This study can not be conducted without the participation of
sufficient subjects in each group. This study can contribute to a better
understanding and early diagnosis in patients with parkinsonian disorders.