Positron Emission Tomography

The neurology PET group consists of two senior clinical scientists, Professor DJ Brooks, MD, DSc (Hartnett Professor of Neurology, Honorary Consultant in Neurology) and Dr Paola Piccini, MD, PhD (Senior Lecturer and Honorary Consultant in Neurology), with substantial support from full time research fellows (currently 10) supported by MRC and Wellcome Trust Clinical Training fellowships and external grants from charities and industry.
Our group main research interests lay in functional imaging (PET and functional MRI) and movement disorders.

Parkinson’s disease (PD) is a chronic progressive neurodegenerative disorder with a peak onset in the sixth decade.  PD patients experience progressive disability; 15% of patients cannot work after 5 years and 80% after 9 years of onset (Bryson HM et al. 1992. Pharmacoeconomics, 2, 118-36). They have a 10 year mortality rate 1.5 times that of contemporary controls and a 30% prevalence of dementia due to direct cortical involvement or concomitant Alzheimer’s disease (Korczyn AD. 2001. J Neurol. 248 Suppl 3: III1-4). Over 100,000 patients are affected in the UK and PD costs the UK National Health Service £380 million per year – mainly due to required residential care (West R. 1991. Parkinson's disease, London: Office of Health Economics). Although symptomatic treatments improve functional abilities and quality of life for PD patients, therapies that modify the underlying pathogenesis are lacking.

Huntington’s disease is an autosomal dominantly inherited neurodegenerative disorder associated with a CAG repeat expansion of the IT15 gene on chromosome 4 (The Huntington's disease collaborative research group. Cell. 199372:971-983). The clinical prevalence is 5-10 per 100,000 in the UK with three times this number carrying the gene mutation. The disease typically presents in the fourth decade with chorea and personality change and leads to dementia and death in 10-15 years. There is currently no effective treatment.

Primary dystonia is a genetic disorder causing involuntary muscle spasms and posturing. Generalised dystonia is severely disabling and has a prevalence of 1:10,000  - young onset cases are often associated with DYT1 gene mutations. Focal dystonia (including writer’s cramp) affects 1:1000 people. Tardive dyskinesia associated with neuroleptic use affects 50% of schizophrenic patients and is severely disabling in 10%.

Over the past years our group has used functional imaging to investigate:
(1) The functional anatomy underlying motor tasks.
(2) The effects of pharmacological manipulations and behaviour on brain dopamine release in healthy subjects and patients with movement disorders.
(3) The pharmacological and brain activation changes associated with the onset, progression, and treatment complications of Parkinson’s disease (PD) and Huntington’s disease (HD).
(4) The effects of putative neuroprotective and restorative therapies in these diseases.



Dopamine release from a graft of fetal midbrain cells visualized in vivo in Parkinson’s disease: reduction of 11C-raclopride binding to D2 receptors in the transplanted left putamen after a methamphetamine challenge (Piccini et al., Nature Neuroscience 1999; 2 (12): 1137-1140).