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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Isolated head tremor is rare, but can be disabling. The authors' experience with the treatment of limb tremor due to essential tremor led them to consider using bilateral thalamic deep brain stimulation (DBS) in two patients presenting only with disabling head tremor. One patient exhibited no peripheral tremor and the other displayed only a slight upper-limb tremor. Both patients underwent placement of units that apply simultaneous bilateral thalamic DBS. Surgical targets were verified by using intraoperative macrostimulation, and the stimulators were implanted during the same surgery. Patients were videotaped preoperatively and at 2, 4, 6, and 9 months postoperatively during periods in which the stimulators were turned on and off. Videotapes were randomized and rated for resting, postural, and action tremors according to the Fahn clinical rating scale for tremor. Because this scale is not designed for head tremor, the patients were also evaluated on the basis of a functional scale that reflected their quality of life and the amount of disability caused by head tremor. Both patients experienced no tremor after their stimulators were turned on and properly adjusted at the 6th postoperative week. The patients were followed for a total of 9 months and results remained stable throughout this period. No complications were encountered. Bilateral thalamic DBS appears to be an effective and safe treatment for isolated head tremor in patients with essential tremor. The authors present a scale for the functional assessment of head tremor.
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PMID:Bilateral thalamic deep brain stimulation for the treatment of head tremor. Report of two cases. 1188 51

Essential tremor (ET) is the most common movement disorder in humans. It is characterized by a postural and kinetic tremor most commonly affecting the forearms and hands. Isolated head tremor has been found in 1-10% of patients, suggesting that ET may be a composite of several phenotypes. The exact pathophysiology of ET is still unknown. ET has been repeatedly shown as a disorder of mild cerebellar degeneration, particularly in postmortem studies. Clinical observations, electrophysiological, volumetric and functional imaging studies all reinforce the fact that the cerebellum is involved in the generation of ET. However, crucial debate exists as to whether ET is a neurodegenerative disease. Data suggesting that it is neurodegenerative include postmortem findings of pathological abnormalities in the brainstem and cerebellum, white matter changes on diffusion tensor imaging, and clinical studies demonstrating an association with cognitive and gait changes. There is also conflicting evidence against ET as a neurodegenerative disease: the improvement of gait abnormalities with ethanol administration, lack of gray matter volume loss on voxel-based morphometry, failure to confirm the prominent presence of Lewy bodies in the locus ceruleus, and other pathological findings. To clarify this issue, future research is needed to describe the mechanism of cellular changes in the ET brain and to understand the order in which they occur. The cerebellum has been shown to be involved in the timing of movement and sensation, acting as an internal timing system that provides the temporal representation of salient events spanning hundreds of milliseconds. It has been reported that cerebellar timing function is altered in patients with ET, showing an increased variability of rhythmic hand movements as well as diminished performance during predictive motor timing task. Based on current knowledge and observations, we argue that ET is essentially linked with cerebellar degeneration, or at least cerebellar dysfunction, together with disturbance of motor timing. We explain the context of our current understanding on this topic, highlighting possible clinical consequences for patients suffering from ET and future research directions.
Tremor Other Hyperkinet Mov (N Y) 2012
PMID:Essential tremor, the cerebellum, and motor timing: towards integrating them into one complex entity. 2343 25

Tremors are commonly encountered in clinical practice and are the most common movement disorders seen. It is defined as a rhythmic, involuntary oscillatory movement of a body part around one or more joints. In the majority of the population, tremor tends to be mild. They have varying etiology; hence, classifying them appropriately helps in identifying the underlying cause. Clinically, tremor is classified as occurring at rest or action. They can also be classified based on their frequency, amplitude, and body part involved. Parkinsonian tremor is the most common cause of rest tremor. Essential tremor (ET) and enhanced physiological tremor are the most common causes of action tremor. Isolated head tremor is more likely to be dystonic rather than ET. Isolated voice tremor could be considered to be a spectrum of ET. Psychogenic tremor is not a diagnosis of exclusion; rather, demonstration of various clinical signs is needed to establish the diagnosis. Severity of tremor and response to treatment can be assessed using clinical rating scales as well as using electrophysiological measurements. The treatment of tremor is symptomatic. Medications are effective in half the cases of essential hand tremor and in refractory patients; deep brain stimulation is an alternative therapy. Midline tremors benefit from botulinum toxin injections. It is also the treatment of choice in dystonic tremor and primary writing tremor.
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PMID:Approach to a tremor patient. 2799 49