title: Patients with rest-tremor and scans with ipsilateral dopaminergic deficit.
abstract: Dopamine transporter imaging is typically abnormal in Parkinson's disease and shows reduced striatal uptake, which is typically greater contralateral to the clinically more affected side. However, tremor-dominant Parkinson's disease patients may have significantly lower uptake in the striatum ipsilateral to the rest-tremor compared to akinetic-rigid PD patients, implying a possible role of an ipsilateral deficit in the generation of rest-tremor.We report here three patients with rest-tremor and the unexpected finding of an ipsilateral presynaptic dopaminergic deficit with normal uptake contralateral to the rest-tremor in dopamine transporter imaging. We divided them in two groups, with and without a corresponding structural lesion in brain imaging. These data may suggest a role of ipsilateral dopaminergic deficit in the generation of rest-tremor. An explanation of these findings could be damage of crossed dopaminergic fibres from the substantia nigra to thalamus, which can cause motor impairment ipsilateral to dopamine depletion experimentally. This is speculative but there is no doubt that these cases exist and we encourage others to report similar cases, as this may assist in the better understanding of the yet unknown pathophysiology of rest-tremor.
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK.
authors.forename: Maria
authors.initials: M
authors.lastname: Aguirregomozcorta
authors.forename: Maria
authors.initials: M
authors.lastname: Stamelou
authors.forename: Angelo
authors.initials: A
authors.lastname: Antonini
authors.forename: Petra
authors.initials: P
authors.lastname: Schwingenschuh
authors.forename: Liz
authors.initials: L
authors.lastname: Prvulovich
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Edwards
authors.forename: John C
authors.initials: JC
authors.lastname: Dickson
authors.forename: Kailash P
authors.initials: KP
authors.lastname: Bhatia
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology*; D004298:Dopamine / Q000172:deficiency*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed; D014202:Tremor / Q000000981:diagnostic imaging / Q000378:metabolism*; D014326:Tropanes; D055815:Young Adult
chemical_list: D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane; D004298:Dopamine