Background
Parkinsonian tremor | Essential tremor | Dystonic tremor | |
---|---|---|---|
Key clinical features | |||
Topography | Hand > others | Hands > head > voice > others | head > Hands > others |
Activation condition | Rest > postural/kinetic | Postural > kinetic > rest | Postural > kinetic > rest |
Symmetry | Asymmetrical | Symmetrical | Asymmetrical |
Suppression of tremor during movement onset | in most cases | not found | rare |
Frequency | 4-6Hz | 4-8 Hz | 7 Hz |
Amplitude | Regular | Regular | Irregular |
Potential accompanying signs | Bradykinesia, rigidity, etc | Impaired tandem gait | Dystonic posture |
Possible pathophysiological basis | |||
Triggering factor | Dopaminergic dysfunction in nigrostriatal system | Reduced inhibition in cerebellum and brainstem | Reduced inhibitory reflex at multiple levels (spinal, brainstem, and cortical, etc.) |
Activated circuit | Cerebello-thalamo-cortical circuit |
Tremor in Parkinson’s disease
Prevalence
Clinical features
Essential tremor
Prevalence
Clinical features
Tremor in dystonia
Prevalence
Clinical features
Monosymptomatic rest tremor (mRT)
Ancillary tests for tremor differential diagnoses
Techniques | Diagnostic reliability | Design | Parkinsonian tremor | Essential tremor | Dystonic tremor | Psychogenic tremor | References |
---|---|---|---|---|---|---|---|
Mean hormonic peak power | Accuracy 94% | Tremulous PD(n = 39) vs. ET(n = 41) | Tremulous PD > ET | - | - | Muthuraman M. Mov Disord. 2011 [47] | |
Coherence entrainment test (CET) | Accuracy 100% | Psychogenic trmeor (n = 10) vs. DT (n = 11) vs. HC(n = 10) | - | - | negative | positive | McAuley J. Mov Disord. 2004 [50] |
Blink reflex recovery curve (BRrc) | Accuracy 100% | DT(n = 10) vs. ET(n = 10) vs. HC(n = 12) | - | Normal | Increased R2 recovery index | - | Nistico R. Neurology. 2012 [51] |
Accuracy 100% | tPD(n = 11) vs. ET with rest tremor(n = 10) vs. HC(n = 20) | Incresed R2 component | Normal at ISI 100 | - | - | Nistico R. Parkinsonism Relat. Disord. 2014 [52] | |
Temporal discrimination movement threshold (TDMT) | PPV 86.7%, NPV 70.8% | ET(n = 19) vs. TAD(n = 20) VS. HC(n = 25) | - | Higher | Normal | - | Tinazzi M. Neurology. 2013 [53] |
Somatosensory Temporal discrimination threshold (TDT) | PPV 100.0%, NPV 74.1% | TAD (n = 20) vs. ET(n = 19) VS. HC(n = 25) | - | Normal | Higher | - | Tinazzi M. Neurology. 2013 [53] |
Reciprocal inhibition (RI) | Not given | CD with arm tremor(n = 13) vs. ET(n = 8) | - | Normal | Partially reduced | - | Munchau L. Brain. 2001 [54] |