MotIoN aDaptive Deep Brain Stimulation for MSA

Aim and patient group:

Multiple System Atrophy is a form of Parkinsonism and is a neurodegenerative condition that is characterized by gait and autonomic failure. The aim of this study is to assess the effects of aDBS of the Pedunculopontine Nucleus (PPN) on autonomic and gait symptoms in a group of 5 patients with MSA. Patients will enter our routine selection process but patients in the study will be selected for predominantly autonomic symptoms as per the inclusion criteria below. The aim is to test whether or not PPN aDBS improves quality of life, and has an effect on a variety of measurable autonomic parameters in this subset of patients. Secondary aims are to assess the safety of DBS in MSA, and to look at the structural projections and effects on brain networks associated with stimulation.

Background:

Deep Brain Stimulation (DBS) is a routine treatment for movement disorders such as Parkinson's disease (PD). In Oxford, around 80 DBS operations per year are performed, and approximately two thirds of these are in patients with PD. Multiple System Atrophy (MSA) is a 'Parkinsonian' condition similar to PD and is a progressive, incurable, neurodegenerative condition characterized by a combination of Parkinsonism, ataxia, and autonomic failure. Any one of these three features may predominate, making diagnosis difficult; however, virtually all patients have autonomic dysfunction. Indeed, autonomic dysfunction is the presenting feature in half of patients that have Parkinsonism or ataxia predominant MSA. The motor manifestations such as gait problems, ataxia, and postural abnormalities are very similar to those encountered by patients with Parkinson's disease, though unfortunately are usually less responsive to dopamine agonists and so can be more disabling. Patients tend to progress more quickly, often confined to a wheelchair within 3-5 years of diagnosis, and death is usually within a decade.

Whilst DBS has sometimes been performed for the treatment of MSA, including in Oxford , the primary outcome measure is usually the motor outcome, despite the fact that the autonomic symptoms are probably the predominant factor in causing a reduced quality of life. This is because DBS is traditionally used to control motor symptoms and the exploration of its effects on autonomic function are relatively new, and pioneered by the investigators.