Tremor-Some Controversial Aspects

Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, Queen Square, London, United Kingdom.
Movement Disorders (Impact Factor: 5.63). 01/2011; 26(1):18-23. DOI: 10.1002/mds.23289
Source: PubMed

ABSTRACT The commonest cause of pathological tremor is essential tremor (ET). However, it has proved difficult to identify genetic mutations causing ET, particularly because other causes of tremor continue to be misdiagnosed as ET. Whether subjects with dystonia or Parkinson's disease (PD) carry an increased genetic risk of developing ET, or vice versa, is controversial. In addition, the notion of a separate disorder of benign tremulous parkinsonism (BTP) has been debated. This article gives a selective viewpoint on some areas of uncertainty and controversy in tremor.

Download full-text


Available from: Kailash Bhatia, Jul 03, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The dystonias are a group of disorders defined by sustained or intermittent muscle contractions that result in involuntary posturing or repetitive movements. There are many different clinical manifestations and causes. Although they traditionally have been ascribed to dysfunction of the basal ganglia, recent evidence has suggested dysfunction may originate from other regions, particularly the cerebellum. This recent evidence has led to an emerging view that dystonia is a network disorder that involves multiple brain regions. The new network model for the pathogenesis of dystonia has raised many questions, particularly regarding the role of the cerebellum. For example, if dystonia may arise from cerebellar dysfunction, then why are there no cerebellar signs in dystonia? Why are focal cerebellar lesions or degenerative cerebellar disorders more commonly associated with ataxia rather than dystonia? Why is dystonia more commonly associated with basal ganglia lesions rather than cerebellar lesions? Can answers obtained from animals be extrapolated to humans? Is there any evidence that the cerebellum is not involved? Finally, what is the practical value of this new model of pathogenesis for the neuroscientist and clinician? This article explores potential answers to these questions.
    Neuroscience 01/2014; 260:23–35.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Essential tremor (ET) and Parkinson's disease (PD) are two of the most common movement disorders. Tremors are the primary symptoms of ET and of some PD patients, the two are often mistaken for each other. Especially since there are no available differentiate tests for the tremor of ET or PD, the early diagnoses mainly based on clinical assessments of medical symptoms, family and medication history, and examination by physicians. There is increasing evidence suggesting an association between ET and PD, such as a similar tremor frequency, overlapping resting tremors (a typical PD tremor), postural tremors (mainly in ET patients) in both ET and PD patients, and many ET patients develop PD later in life. Although it is difficult to make a differential diagnosis of ET and tremor-dominant PD based on clinical assessment, recent developments of objective measurements, such as brain imaging, neuropathology, and genetic analysis, has opened a helpful window for distinguishing ET from PD. In this mini review, we included literatures of ET and PD studies and discussed various advanced methods for differential diagnosis between ET and PD such as neuroimaging, genetic markers, tremor intensity and frequency, and drug-responses.
    Frontiers in Cellular Neuroscience 07/2013; 7:118. DOI:10.3389/fncel.2013.00118
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hyperkinesias are heterogeneous conditions that share the feature of production of involuntary, abnormal, excessive movements. Tremor, dystonia, and chorea are amongst the most common of these phenomena. In this focused review there is a discussion of difficult issues in hyperkinesias. The first one is the differential diagnosis between essential tremor (ET) and Parkinson's disease (PD). They are readily distinguishable in the majority of patients but in a few subjects ET coexist with parkinsonian features whose underlying mechanism remains to be determined. The second topic of the review is dystonic tremor. Although increasingly diagnosed and reported as accounting for the majority of scans without evidence of dopaminergic deficits, its diagnostic criteria are ill-defined and differentiation from PD and ET can be challenging. In the last section, there is a discussion of the differential diagnosis of Sydenham's chorea (SC), the most common cause of chorea in children. In a few patients, vascular disease, systemic lupus erythematosus, and primary antiphospholipid antibody syndrome can mimic SC.
    Frontiers in Neurology 10/2012; 3:151. DOI:10.3389/fneur.2012.00151