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Tremors: A concept analysis.

AIM: This article seeks to clarify and define the concept of tremors. DESIGN: The Walker & Avant (2005) concept analysis method was followed. METHODS: A search of PubMed, Academic Search Complete, CINAHL, ERIC, Google and Google Scholar was performed. RESULTS: Through this process, uses of the concept were assessed including definitions and categories of tremors. Defining attributes were found to include "movement disorder," "shaking motions," "involuntary," "oscillatory," "rhythmic," "not painful or life threatening," "always present but variable" and "can sometimes be repressed." We ident…

Avicenna and Tremor of the Heart.

Physicians have been mesmerized by a beating heart and its relationship to the peripheral pulse since the ancient times. Although William Harvey in 1628 was credited as the first to describe "fibrillation of the auricles," chaotic irregularity of the pulse was acknowledged by some as early as in the antiquity. In fact, a close examination of history may reveal a description of cardiac arrhythmias long before the era of modern medicine.

Essential tremor and the cerebellum.

Essential tremor (ET) is a progressive and highly prevalent neurologic disease. Along with the tremors, mild to moderate gait ataxia and other signs of cerebellar dysfunction may occur (i.e., subtle saccadic eye movement abnormalities and abnormalities of motor timing) as well as cognitive features, some of which may be due to cerebellar dysfunction. Numerous neuroimaging studies indicate the presence of functional, metabolic, and structural abnormalities in the cerebellum of a patient with ET. In tandem with these clinical and imaging studies, which were gathering increasing support for the n…

Surgery for Dystonia and Tremor.

Surgical procedures for dystonia and tremor have evolved over the past few decades, and our understanding of risk, benefit, and predictive factors has increased substantially in that time. Deep brain stimulation (DBS) is the most utilized surgical treatment for dystonia and tremor, though lesioning remains an effective option in appropriate patients. Dystonic syndromes that have shown a substantial reduction in severity secondary to DBS are isolated dystonia, including generalized, cervical, and segmental, as well as acquired dystonia such as tardive dystonia. Essential tremor is quite amenabl…

Task Specific Tremors.

A patient reported bilateral hand tremors when writing but not with other tasks. These "task specific" tremors are considered subcategories of essential tremor. Primary writing tremor, in which the tremor occurs only with writing, is probably the most common. The important teaching point is that the "standard" tremor assessment, watching the patient holding a sustained posture and touching his finger to the examiner's and then back to the nose is not adequate. Patients should be tested doing the activity that causes them the most difficulty.

The many roads to tremor.

Tremor represents one of the most prominent examples of aberrant synchronisation within the human motor system, and Essential Tremor (ET) is by far the most common tremor disorder. Yet, even within ET there is considerable variation, and patients may have contrasting amounts of postural and intention tremor. Recently, Pedrosa et al. (2013) challenged tremor circuits in a cohort of patients presenting with ET, by applying low-frequency deep brain stimulation within thalamus. This interventional approach provided strong evidence that distinct (yet possibly overlapping) neural substrates are resp…

Differentiation and diagnosis of tremor.

Tremor, an involuntary, rhythmic, oscillatory movement of a body part, is the most common movement disorder encountered in clinical practice. Rest tremors occur in a body part that is relaxed and completely supported against gravity. Action tremors occur with voluntary contraction of a muscle and can be further subdivided into postural, isometric, and kinetic tremors. All persons have low-amplitude, high-frequency physiologic tremors at rest and during action that are not reported as symptomatic. The most common pathologic tremor is essential tremor. In one-half of cases, it is transmitted in …

The Bereitschaftspotential in essential tremor.

OBJECTIVE: Essential tremor (ET) is an involuntary postural oscillation. It is unclear to which extent motor cortical activity in preparation of volitional movement is abnormal in ET. We measured the Bereitschaftspotential (BP) to address this question. METHODS: Given the known influence of the cerebello-dentato-thalamo-cortical projection in the generation of the BP, patients were divided into two groups, defined by purely postural tremor (ET(PT)) or additional presence of intention tremor (ET(IT)) and compared to healthy controls. BP was recorded during self-paced rapid wrist extension move…

An update on essential tremor.

Essential tremor is a well-defined syndrome of postural and kinetic tremor in a characteristic distribution. In some patients, impaired tandem walking, intention tremor, and rest tremor are also seen. An increasing body of clinical, neuropathological, and epidemiologic evidence suggests that essential tremor is a heterogeneous disorder. The evidence is discussed in this update. Recent advances in the treatment of this condition are also reviewed.

Tremor in patients with migraine.

BACKGROUND: It has been suggested that patients with migraine are at a higher risk of developing essential tremor (ET). In addition, it was shown that patients with migraine are at higher risk of subclinical vascular infarcts in the cerebellum, a structure believed to be implicated in ET. OBJECTIVE: Determine whether patients with migraine who do not show clinically detectable ET have subtle alteration in their physiological tremor characteristics that may serve as a predictor for the eventual appearance of ET. METHODS: The physiological tremor of 30 patients with migraine (25 women, mean ag…

Pathophysiology of nonparkinsonian tremors.

Patients with nonparkinsonian tremors are the second largest group treated with functional neurosurgery. We summarize the present pathophysiological knowledge of these conditions. Essential tremor (ET) may be due to oscillations within the olivocerebellar circuit. There is experimental evidence from animal models for such a mechanism, and clinical data indicate an abnormal function of the cerebellum in ET. Cerebellar tremor may be closely related to the tremor seen in advanced ET. The malfunction of the cerebellum causes a pathological feed-forward control. Additionally an oscillator within th…

Novel Objective Tool to Assess Tremor Reveals Unilateral Focused Ultrasound Improves Tremor Bilaterally.

BACKGROUND: Tremor in essential tremor and in tremor-dominant Parkinson's disease is assessed by subjective observations in patients undergoing focused ultrasound thalamotomy, a minimally invasive procedure intended to alleviate tremor in these patients. OBJECTIVE: To develop an objective tool for tremor analysis to be used before and after focused ultrasound thalamotomy treatment in the treated hand (contralateral to ablation) and non-treated (ipsilateral to ablation). METHODS: Using image processing and signal processing that utilized images of a Archimedes spiral drawing, we created a too…

Тремор и инвалидность после глубокой стимуляции мозга, вызванной множественным склерозом.

Трэмор в множественных склерозах (MS) часто отличается от лекарств. Глубокая стимуляция мозга может помочь, но возможные побочные эффекты и обострение заболеваний ограничивают ее использование. ЦЕЛИ: Оценка результатов ДБС с точки зрения дрожжей, связанных с MS. МЕТОДЫ: Ретроспективное обследование 18 пациентов с связанными с MS троморами, которые прошли через DBS, анализ Расширенной шкалы инвалидности (EDSS) и Tahn-Tolosa-Marin (FTM). Результаты: Медианный возраст при хирургической операции составлял 49,5 года (диапазон 28-75), а послеоперационный период - 2,5 года (диапазон 0-22 года). Никак

Совпадение в аннотации оригинала
BACKGROUND: Tremor in multiple sclerosis (MS) is often refractory to medications. Deep brain stimulation (DBS) may help, but possible side effects and disease exacerbation limit its use. OBJECTIVES: Evaluate outcomes of DBS for MS-associated tremor. METHODS: Retrospective review of 18 patients with MS-associated tremor who underwent DBS, analyzing Expanded…

Essential Tremor accentuates the pattern of tremor-band coherence between upper-limb muscles.

Although Essential Tremor is one of the most common movement disorders, current treatment options are relatively limited. Peripheral tremor suppression methods have shown potential, but we do not currently know which muscles are most responsible for patients' tremor, making it difficult to optimize suppression methods. The purpose of this study was to quantify the relationships between the tremorogenic activity in muscles throughout the upper limb. Muscle activity was recorded from the 15 major superficial upper-limb muscles in 24 subjects with Essential Tremor while they held various postures…

Fitts' Law Based Performance Metrics to Quantify Tremor in Individuals With Essential Tremor.

Current methods of evaluating essential tremor (ET) either rely on subjective ratings or use limited tremor metrics (i.e., severity/amplitude and frequency). In this study, we explored performance metrics from Fitts' law tasks that replicate and expand existing tremor metrics, to enable low-cost, home-based tremor quantification and analyze the cursor movements of individuals using a 3D mouse while performing a collection of drawing tasks. We analyzed the 3D mouse cursor movements of 11 patients with ET and three controls, on three computer-based tasks-a spiral navigation (SPN) task, a rectang…

Intramuscular Stimulation of Muscle Afferents Attains Prolonged Tremor Reduction in Essential Tremor Patients.

This study proposes and clinically tests intramuscular electrical stimulation below motor threshold to achieve prolonged reduction of wrist flexion/extension tremor in Essential Tremor (ET) patients. The developed system consisted of an intramuscular thin-film electrode structure that included both stimulation and electromyography (EMG) recording electrodes, and a control algorithm for the timing of intramuscular stimulation based on EMG (closed-loop stimulation). Data were recorded from nine ET patients with wrist flexion/extension tremor recruited from the Gregorio Marañón Hospital (Madrid, …