1 Department of Neurology, Christchurch Hospital, Private Bag 4710, Christchurch, New Zealand; Department of Neurology, Auckland City Hospital, Auckland, New Zealand.
2 Department of General Medicine, Christchurch Hospital, Christchurch, New Zealand.
3 Department of Neurology, Christchurch Hospital, Private Bag 4710, Christchurch, New Zealand. Electronic address: John.Fink@cdhb.health.nz.