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Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dizziness as defined herein will include an illusion of motion caused by various degrees of ischemia to the vestibular pathway or its interconnecting pathways. "Syndrome," such as the lateral medullary syndrome, denotes a macroinfarct, while a microinfarct or an area of incomplete infarct (where there may develop an incomplete degeneration of the neural tissue secondary to the arteriolar microatheromatous stenosis) may cause only one neurologic deficit, such as dizziness per se as the only symptom. However, the latter may presage a larger and more debilitating neurologic deficit. The transcranial Doppler, used to track sequentially the larger basal arteries of the brain, specifically the vertebrobasilar arterial system, is an addition to noninvasive diagnostic methods of separating vascular problems from other causes of dizziness.
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PMID:Vascular dizziness and transcranial Doppler ultrasonography. 250 61

The symptom of sudden tilting of the visual surroundings is described in detail based on experience with five patients. Patients perceive the visual fields as suddenly turning through a variable arc, most frequently 90-180 degrees, usually associated with dizziness. In three patients with vertebral-basilar artery disease, visual tilting was more closely related to local pontomedullary ischemia than to posterior cortical ischemia. It is suggested that most instances of this illusion are due to disorders of the vestibular-otolithic apparatus or its central connections, most frequently from vertebral-basilar ischemia.
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PMID:Illusion of tilting of the visual environment. Report of five cases. 622 17

Dizziness is a nonspecific symptom caused by many different pathophysiologic mechanisms. Vertigo, an illusion of movement, indicates a lesion within the vestibular system. The duration of attacks and associated symptoms helps to determine the site of lesion and likely diagnosis. Examination of the dizzy patient should include a careful assessment of gait and balance and a search for spontaneous and positional nystagmus. The vestibulo-ocular reflex can be evaluated qualitatively at the bedside with the doll's eye, dynamic visual acuity, and ice water caloric tests. Each test provides different information about vestibular function.
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PMID:Approach to the evaluation of the dizzy patient. 857 Feb 43

As dizziness can be caused by so many different pathophysiological mechanisms, it is crucial to determine the type of dizziness before proceeding with the diagnostic evaluation. Vertigo, defined as an illusion of movement, is an important subtype of dizziness that indicates a lesion somewhere within the vestibular system. Probably the most useful feature for differentiating between peripheral and central causes of vertigo is the associated symptoms. Vertigo of peripheral origin is typically associated with auditory symptoms such as hearing loss and tinnitus, while vertigo of central origin is nearly always associated with neurological symptoms such as diplopia, weakness, numbness and ataxia. Each of the common causes of vertigo has a characteristic clinical profile that should suggest a likely diagnosis after the history and examination are complete. Probably the most important treatment breakthrough is the positional manoeuvre that reliably cures benign positional vertigo (see Chapter 6). The treatment strategy for an acute peripheral vestibular lesion has evolved over the past few years. Patients are encouraged to return to normal physical activity as rapidly as possible. Repeated head, eye and body movements (vestibular rehabilitation) help the brain to recalibrate the relationship between visual, proprioceptive and vestibular signals (Chapter 9).
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PMID:Approach to the dizzy patient. 787 2

Vertigo and dizziness are common complaints encountered in clinical practice. The patient's history and a thorough otoneurological evaluation are essential for identifying the specific pathology behind the patient's complaints. If the patient reports an illusion of movement (vertigo), this most likely indicates an imbalance within the vestibular system. A sensation of rotatory movement together with a spontaneous nystagmus suggests a lesion involving the semicircular canals, while an illusion of linear movement indicates a disturbance of the otoliths. Nystagmus of central origin or caused by a peripheral vestibular lesion can usually be distinguished by other features in the history or on clinical examination. While peripheral vestibular lesions usually lead to a mixed horizontal-torsional or vertical-torsional nystagmus, a pure vertical or pure torsional nystagmus is always caused by a central lesion. With simple bedside tests such as head-shaking nystagmus and rapid head impulses deficits in labyrinthine function can clearly be detected. For a more thorough investigation of vestibular function at the level of individual semicircular canals and the otoliths, modern techniques are now available such as three-dimensional eye movement vector analysis for the evaluation of individual semicircular canal function, measurement of the subjective visual vertical for utricular, and click-evoked myogenic potentials for saccular testing.
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PMID:Assessing vestibular function: which tests, when? 1089 64

Dizziness is a frequent presenting complaint in emergency department patients. Although seen in patients of all ages, it is more prevalent in patients older than 50 years of age. Vertigo represents a subset of dizziness and is defined as an illusion of movement, usually rotational, of the patient or the patient's surroundings. The illusion of motion may be of oneself (subjective vertigo) or of external objects (objective vertigo). The emergency physician should consider a large differential in the evaluation of vertigo with special attention to whether the vertigo is central or peripheral in origin.
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PMID:Benign paroxysmal positional vertigo: diagnosis and treatment in the emergency department--a review of the literature and discussion of canalith-repositioning maneuvers. 1127 32

This work uses clinical examples to explore sources of conflict and denial of patients and physicians during contraception consultations. The discovery of oral contraceptives (OCs) and improvements in mechanical contraception raised hopes that couples could achieve total control of their fertility. But continued high abortion rates and the persistence of sexual problems and maladjustments have demonstrated that contraception alone is not a panacea. Conflicts about contraception may be conscious and quickly expressed during a consultation, even if a medical pretext is given. The resentment when 1 partner desires a child and the other does not for example can translate into a conflict about contraception. Some women are fully aware of their own ambivalence about pregnancy and contraception and able to express it openly, but very often the woman's concerns are expressed by questions, fears, and verbal slips. The fear that pills are unnatural or will cause congenital defects can be interpreted as an expression of guilt over the pleasure that pills permit. Sterility is the ultimate fear caused by this unlimited possibility for pleasure. In the majority of cases, physical complaints are the means by which contraception clients address their physicians. In some cases, intolerance to OCs may actually be a hysterical manifestation that is not understood. Such symptoms as nausea, breast swelling, dizziness, vomiting, nervousness, and insomnia may be signs of early pregnancy as well as of intolerance for pills. Intolerance to pills may be caused by intolerance of a sexuality in which all things seem possible but in which the individual feels unrecognized by the partner. The resulting aggression may be turned inward in the form of a morbid symptom or of forgetting or stopping pill use, recourse to abortion, and demand for recognition. Acting out, especially by adolescents, is common in the area of contraception. In some cases the psychological or emotional needs of the patient might be better met by contraception that leaves some risk of failure, such as low-dose progestins or local methods. Their relative efficacy may allow the ambivalent desire for a child not to be completely stifled. Cases also arise in which patients use contraceptives to mask problems and to give the illusion of a normally functioning body. The possibility of having a child is very seldom raised during contraceptive consultations, perhaps because for the physician contraception subconsciously evokes the forces of death. The doctor can take refuge in the technical aspects of contraception, ignoring the emotional needs of the client.
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PMID:[The difficulties of contraception: conflicts and paradoxes]. 1231 42

This review deals with two syndromes, oscillopsia and visual vertigo. Oscillopsia is the illusion of oscillation of the visual surroundings. For diagnosis purposes one should ask, when does the oscillopsia occur? If oscillopsia is only present during head (or whole body) movements, the likely underlying cause is a bilateral defect in the vestibulo-ocular reflex (VOR). The more common causes are post meningitic vestibular damage, gentamicin ototoxicity or bilateral idiopathic vestibular failure. When oscillopsia develops after specific head positions, it is usually due to a positional nystagmus, usually the result of brainstem-cerebellar disease. When the oscillopsia is largely unrelated to head movements, one should ask, is it fairly constant or is it in attacks (paroxysmal)? If the oscillopsia is constant it is usually due to the presence of a clinically observable nystagmus; the most common is downbeat nystagmus but the most visually disabling is pendular nystagmus. If the oscillopsia comes in brief attacks it is usually due to a paroxysmal nystagmus as observed in irritative VIII nerve and brainstem lesions. However, the most common cause of paroxysmal oscillopsia is a non organic condition called voluntary nystagmus. Treatment of oscillopsia is often pharmacological but disappointing; the best chance of success is carbamazepine for paroxysmal disorders secondary to structural vestibular nerve/nuclear lesions.Visual vertigo should not be confused with oscillopsia. It can be defined as dizziness provoked by visual environments with large size (full field) repetitive or moving visual patterns. Patients with visual vertigo report discomfort in supermarkets and when viewing movement of large visual objects, eg crowds, traffic, clouds or foliage. Visual vertigo is present in many patients with a history of a peripheral vestibular disorder, particularly those who are visually dependent (ie subjects who use vision preferentially for postural and space orientation control). Patients with visual vertigo benefit from the addition to their standard vestibular rehabilitation of optic flow (optokinetic) stimuli and exercises involving visuo-vestibular conflict.
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PMID:Vision and vertigo: some visual aspects of vestibular disorders. 1508 81

Seven hours after 39 migraineurs and 37 controls consumed an amino acid drink that contained or omitted l-tryptophan (thereby reducing brain serotonin synthesis), motion sickness was provoked by the visual illusion of movement. Tryptophan depletion boosted dizziness, nausea, and the illusion of movement in controls to levels that approached those of migraineurs. Thus, reduced brain serotonin activity may promote vestibuloocular disturbances during motion sickness and attacks of migraine.
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PMID:Effect of tryptophan depletion on symptoms of motion sickness in migraineurs. 1611 3

Vertigo can be defined as an illusion or hallucination of movement. The control of balance is complicated. Vertigo can be caused by many different pathologies, some of which are potentially life threatening. An important differentiation is whether the symptoms of vertigo originate from a central or peripheral origin. Clues to a central origin are other brainstem symptoms or signs of acute onset such as headache, deafness and other neurological findings. These patients warrant urgent referral and investigation. Red flags in patients with vertigo include: headache; neurological symptoms; and neurological signs. It is useful to categorise vertigo into acute and chronic. The former usually has a single mechanism whereas chronic dizziness is often multifactorial. History is usually the most important part of the assessment. Key questions should be asked and it is vital to establish if the patient is suffering from vertigo or some other complaint such as anxiety or syncope. A neurological and otological examination should be performed, appropriate to the history. Assessment of gait and posture is crucial. If the patient has positional vertigo then a Hallpike test should be performed. Visual acuity should be checked as vision is a vital part of the balance system. The cranial nerves should be tested in particular eye movements for any ophthalmoplegia pointing to focal cranial nerve pathology and for nystagmus. The rest of the neurological examination should exclude evidence of central disease, in particular cerebellar disease, and neuropathy. If syncope is suspected it is wise to perform an extensive systemic examination in particular lying and standing BP, and cardiovascular and respiratory system assessments.
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PMID:Systematic approach needed to establish cause of vertigo. 2151 May 8


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