ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Our detailed understanding of the physiology and anatomy of the ocular motor system allows an accurate differential diagnosis of pathological eye movement patterns. This review covers important clinical studies and studies in basic research relevant for the neurologist published during the past year.

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Acute vestibulopathy is characterized by the acute or subacute onset of vertigo, dizziness or imbalance with or without ocular motor, sensory, postural or autonomic symptoms and signs, and can last for seconds to up to several days. Acute vestibular lesions may result from a hypofunction or from pathological excitation of various peripheral or central vestibular structures (labyrinth, vestibular nerve, vestibular nuclei, cerebellum or ascending pathways to the thalamus and the cortex). This update focuses on new aspects of the aetiology, pathophysiology, epidemiology, and treatment of (i) acute peripheral disorders (benign paroxysmal positioning vertigo, vestibular neuritis, Menière's disease, perilymph fistula, especially ‘superior canal dehiscence syndrome’, vestibular paroxysmia); and (ii) acute central vestibular disorders (especially ‘vestibular migraine’). Finally, the clinical relevance of recent diagnostic tools (three-dimensional analysis of eye movement, imaging techniques) is discussed.

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Loud clicks, short tone bursts, head taps and short duration transmastoid currents are all capable of activating vestibular receptors and evoking reflex changes in tonic electromyogram activity within the sternocleidomastoid muscles. Because they derive from averaged electromyograms, the responses are termed ‘vestibular evoked myogenic potentials’. The earliest response ipsilateral to a loud click, p13n23, is dependent upon vestibular activation, specifically saccular afferents. These new techniques are beginning to be applied clinically. An important application is in suspected cases of the Tullio phenomenon, a condition that is characterized by a pathological reduction in click threshold. The techniques have also been applied in the assessment of otolith function, vestibular neuritis, Meniere's disease and vestibular nerve tumours (acoustic neuromas).

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Steroid, amine and peptide hormones affect the peripheral vestibular system. Vasopressin hypersensitivity of the endolymphatic sac may be implicated in the pathogenesis of Meniere's disease. Specific vasopressin antagonists will help define the role of vasopressin in Meniere's disease. The modulation of central vestibular pathways by neuroactive steroids may involve effects on γ-aminobutyric acid-ergic and glutaminergic pathways. The vestibular nuclei also express enzymes that are important in the synthesis of steroids and the modulation of their activity. Steroids mediate both facilitatory and deleterious effects of stress on vestibular compensation. The quality and quantity of stressor that determines the pattern of hormonal output, may be important. Clinical observation suggests that episodic ataxia type 2, a P/Q calcium channelopathy, may be phenotypically modulated by endocrine fluctuations. Steroid hormones may affect the episodic ataxia type 2 phenotype by modulation of voltage-gated calcium channel activity via second messenger systems and ion channel subunit expression. Despite evidence to support the link, the role of the endocrine system in vestibular function and disease is as yet virtually unexplored.

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

There is considerable evidence to suggest that hearing and vestibular function can be influenced by autoimmune processes. A number of systemic autoimmune disorders include hearing loss and vertigo as part of their constellation of symptoms. Although classic evidence for a specific autoimmune etiology mediated by immune response directed solely at the inner ear is elusive, it appears that autoimmune damage can also exist as an entity confined to the labyrinth. Antigenic targets of autoimmunity within the labyrinth seem to be diverse. Partly because of this, the condition is difficult to diagnose. However, autoimmune disorders of the inner ear are of special interest since they are among the few forms of hearing loss that are amenable to medical treatment. Recent progress in understanding the etiology, diagnosis and treatment of autoimmune damage to the inner ear is reviewed.

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Anxiety and dizziness are co-morbid symptoms in a larger percentage of patients than would be expected from chance alone. Such patients have an increased handicap and poorer prognosis. In this review, we discuss the interface between vestibular disorders and anxiety disorders. The two conditions are functionally related via both somatopsychic and psychosomatic mechanisms, and are linked via overlapping neural circuits that include monoaminergic pathways and the parabrachial nucleus network. An alternative conceptualization to the common notion of ‘psychogenic’ dizziness is presented. Implications for patient management are discussed.

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Functional imaging in humans reveals the interplay of the many components of the human visual system: how they process the various types of information contained in the image to recover characteristics of the three-dimensional world surrounding us, but also how, in the course of this process, the retinal image is gradually integrated with non-retinal signals to provide information about the outside world in a format useful to other non-visual brain regions.

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Nonvalvular atrial fibrillation is the most prevalent dysrrhythmia, and carries with it an at least fivefold increased risk of ischaemic stroke. Currently, the implementation and optimization of prophylactic therapy (with warfarin or acetylsalicylic acid) is the most effective approach, at the population level, to optimize outcomes in patients with atrial fibrillation. Therefore, clinical trial evidence regarding warfarin and acetylsalicylic acid in stroke prophylaxis is highlighted. Recently, considerable data have emerged that indicate suboptimal use of warfarin in clinical practice (both in terms of the prescription and titration of therapy). Narrowing this gap between research evidence and clinical practice may be accomplished by identifying those patients who are eligible for prophylaxis, and then maintaining them at an adequate level of anticoagulation.

ISSN:1350-7540    

出版商:OVID    

年代:2001

数据来源: OVID