MOVEMENT DISORDER RESEARCH IN THE NEUROPSYCHIATRY UNIT

The Neuropsychiatry Unit has assessed patients with movement disorders since its inception, and since its move to the Royal Melbourne Hospital in 1992 has assessed and treated patients with Huntington's disease (HD) for almost two decades. Because of our research interest in neuroimaging, we are undertaking neuroimaging research in a group of movement disorders, utilising MRI scans from our own group in addition to images from other groups.
BRAIN CHANGES IN HUNTINGTON'S DISEASE

Dr Velakoulis has been working with Dr Chua from Monash University and A/Prof Walterfang from the Unit in examining subcortical structures in Huntington's disease, in addition to examining brain connectivity in HD. We are currently extending this work with Professor Paul Thompson at UCLA.
Stacks Image 93
Left and right caudate changes in HD patients. This image, from in preparation work using SPHARM, shows the left and right caudate, with significance maps on the left, and difference maps (in mm) on the right. Areas in blue on significance maps show no change, and areas in red show highly significant change. This allows us to understand the relationship between motor and cognitive changes in HD.
BRAIN CHANGES IN PROGRESSIVE SUPRANUCLEAR PALSY

With Professor Jeff Looi from ANU and Dr Christofer Nilsson from the University of Lund, we have examined the shape of the striatum in progressive supranuclear palsy (PSP), a Parkinson's-like disorder of balance and movement that often presents with frontal cortical changes. We showed that brainstem measures of midbrain atrophy were reliable illness indicators, and that there were also significant changes occurring in striatal regions connecting to frontal brain regions.

This paper can be found here.

Looi et al. Morphometric analysis of subcortical structures in progressive supranuclear palsy: In vivo evidence of neostriatal and mesencephalic atrophy. Psychiatry Research Neuroimaging in press, 2011.
Stacks Image 94
Changes in the right caudate in PSP. As in the above image, significance and distance maps in the right caudate in patients with PSP compared to controls.
Stacks Image 95
Midbrain changes in PSP. Using mid-sagittal images, we showed that PSP patients demonstrate significant midbrain atrophy (the green section) compared to the pons (the yellow section). This sign allows clinicians to determine if a patient's brain scan is suggestive of PSP in the setting of significant Parkinsonian symptoms.
STRIATAL CHANGES IN NEUROACANTHOCYTOSIS

With colleagues Professors Adrian Danek (Ludwig-Maxmillians Universitat, Munich) and Ruth Walker (Mount Sinai Medical School, New York) we analysed striatal structure in an exceptionally rare neurogenetic disorder,
chorea-acanthocytosis (ChAc). ChAc is one of the group of neuroacanthocytoses, which frequently present with movement disorders very much like HD.

We showed that there are massive reductions in total caudate and putaminal volume, in the order of >60%, which reliably differentiate patients from controls. Using shape analysis, we explored the hypothesis that the high rate of obsessive-compulsive disorder (OCD) in ChAc is secondary to disruption of fronto-striatal loops that connect through the head of the caudate nucleus, in particular the lateral orbitofrontal loop. Shape analysis showed that whilst global reduction is present, it seems particularly concentrated in the head of the caudate, consistent with this hypothesis.

This paper can be found
here.

Walterfang et al. Shape alterations in the striatum in chorea-acanthocytosis. Psychiatry Research 192: 29-36, 2011.
Stacks Image 96
Caudate volume by group. Caudate volumes in the ChAc group completely separate from controls, showing that caudate volume is a very strong diagnostic marker.
Stacks Image 97
Regional shape change in left and right caudate. Whilst in the left caudate reduction is more widespread, in the right caudate much of the reduction is focussed around the caudate head, suggesting particular disruption to fronto-striatal loops.