Monosymptomatic resting tremor and Parkinson's disease: a multitracer positron emission tomographic study

Mov Disord. 2002 Jul;17(4):782-8. doi: 10.1002/mds.10125.


We sought to elucidate the relationship between monosymptomatic resting tremor (mRT) and Parkinson's disease (PD). We studied eight mRT patients (mean Hoehn and Yahr [H&Y], 1.1 +/- 0.4), eight patients with PD (mean H&Y, 1.5 +/- 0.8), who showed all three classic parkinsonian symptoms, and seven age-matched healthy subjects. Subjects underwent cerebral magnetic resonance imaging (MRI) and multitracer positron emission tomography (PET) with 6-[(18)F]fluoro-L-dopa (F-dopa), [(18)F]fluorodeoxyglucose (FDG), and [(11)C]raclopride (RACLO). PD and mRT patients did not show significant differences in F-dopa-, RACLO-, or FDG-PET scans. In F-dopa- and RACLO-PET, significant differences between the pooled patient data and control subjects were found for the following regions: anterior and posterior putamen ipsilateral and contralateral to the more affected body side, and ipsilateral and contralateral putaminal gradients of the K(i) values. Furthermore, we found a difference for the normalized glucose values of the whole cerebellum between the control group (0.94 +/- 0.06) and PD patients (1.01 +/- 0.04; P < 0.05) but not for the mRT group (0.97 +/- 0.03). Our findings indicate that monosymptomatic resting tremor represents a phenotype of Parkinson's disease, with a nearly identical striatal dopaminergic deficit and postsynaptic D2-receptor upregulation in both patient groups. We suggest that the cerebellar metabolic hyperactivity in PD is closer related to akinesia and rigidity rather than to tremor.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Brain / diagnostic imaging*
  • Brain / physiopathology
  • Cerebellum / diagnostic imaging
  • Cerebellum / physiopathology
  • Dihydroxyphenylalanine / analogs & derivatives*
  • Dominance, Cerebral / physiology
  • Energy Metabolism / physiology
  • Female
  • Fluorodeoxyglucose F18
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Neurologic Examination
  • Parkinson Disease / diagnostic imaging*
  • Parkinson Disease / physiopathology
  • Putamen / diagnostic imaging
  • Putamen / physiopathology
  • Raclopride
  • Receptors, Dopamine D2 / physiology
  • Reference Values
  • Tomography, Emission-Computed / methods*
  • Tremor / diagnostic imaging*
  • Tremor / physiopathology
  • Up-Regulation / physiology


  • Receptors, Dopamine D2
  • Fluorodeoxyglucose F18
  • fluorodopa F 18
  • Raclopride
  • Dihydroxyphenylalanine