Vertigo is a symptom in which a person feels as if they or objects around him move when they are not. Often feels like a spinning or swaying motion. It may be associated with nausea, vomiting, sweating, or difficulty walking. It's usually worse when the head is moved. Vertigo is the most common dizziness type.
The most common diseases that result in vertigo are benign paroxysmal positional vertigo (BPPV), MÃÆ' Â © niÃÆ'¨re disease, and labyrinthitis. Less common causes include stroke, brain tumor, brain injury, multiple sclerosis, migraine, trauma, and uneven pressure between the middle ear. Physiological vertigo may occur after being exposed to movement for prolonged periods such as when on a ship or just following a spin with closed eyes. Other causes may include exposure to toxins such as carbon monoxide, alcohol, or aspirin. Vertigo usually indicates a problem in the vestibular system. Other causes of dizziness include presyncope, disequilibrium, and non-specific dizziness.
A benign paroxysmal positional vertigo is more likely in someone who has repeated vertigo episodes with movement and is otherwise normal between these episodes. The vertigo episode should last less than a minute. Dix-Hallpike tests usually produce a period of rapid eye movement known as nystagmus under these conditions. In MÃÆ' Â © niÃÆ'¨re disease there is often ringing in the ears, hearing loss, and vertigo attacks lasting more than twenty minutes. In labyrinthitis, the onset of vertigo is sudden and nystagmus occurs without movement. In this condition vertigo can last for days. More severe causes should also be considered. This is especially true if other problems such as weakness, headache, double vision, or numbness occur.
Dizziness affects about 20-40% of people at some point of time, while about 7.5-10% has vertigo. About 5% have vertigo in a given year. It becomes more common with age and affects women two to three times more often than men. Vertigo accounts for about 2-3% of emergency department visits in developed countries.
Video Vertigo
Classification
Vertigo is classified as peripheral or central depending on the location of vestibular pathway dysfunction, although it can also be caused by psychological factors.
Vertigo can also be classified into objective, subjective, and pseudovertigo. Objectively objective describes when the person has a sensation that objects are stationary in a moving environment. Vertigo subjective refers to when people feel as if they are moving. The third type is known as pseudovertigo, an intensive sensation of rotation inside a person's head. While this classification appears in textbooks, it has nothing to do with pathophysiology or vertigo treatment.
Peripherals
Vertigo caused by problems with the inner ear or vestibular system, consisting of the semicircular canal, the vestibule (utrikulus and saccule), and the vestibular nerve are called "peripheral", "otologic" or "vestibular" vertigo. The most common cause is benign paroxysmal positional vertigo (BPPV), which accounts for 32% of all peripheral vertigo. Other causes include MÃÆ' Â © niÃÆ'¨re (12%), superior canal dehiscence syndrome, labyrinthitis, and visual vertigo. Any cause of inflammation such as the common cold, influenza, and bacterial infections can cause transient vertigo if it involves the inner ear, as well as chemical insult (eg, aminoglycosides) or physical trauma (eg, skull fracture). Motion sickness is sometimes classified as a cause of peripheral vertigo.
People with peripheral vertigo usually present with mild to moderate imbalance, nausea, vomiting, hearing loss, tinnitus, fullness, and pain in the ears. In addition, lesions in the internal auditory canal may be related to facial weakness on the same side. Because of the rapid compensation process, acute vertigo as a result of peripheral lesions tends to improve in a short time (day to week).
Middle
Vertigo arising from injury to the central central nervous system (CNS), often from lesions in the brain stem or cerebellum, is called "central" vertigo and is generally associated with less prominent motion illusions and nausea than peripheral origin vertigo. Central vertigo may have accompanying neurological deficits (such as slurred speech and double vision), and pathological nystagmus (which is purely vertical/torsional). Central pathology can cause disequilibrium which is an unbalanced sensation. Balance disorders associated with central lesions cause vertigo often so severe that many patients can not stand or walk.
A number of conditions involving the central nervous system may cause vertigo including: lesions caused by infarction or bleeding, tumors present in the corner of cerebellopontine such as vestibular schwannoma or cerebellar tumors, epilepsy, cervical spine disorders such as cervical spondylosis, degenerative ataxia disorders, migraine headaches, lateral medullary syndrome, Chiari malformation, multiple sclerosis, parkinsonism, and cerebral dysfunction. Central vertigo may not improve or may be slower than vertigo caused by disturbances in peripheral structures.
Maps Vertigo
Signs and symptoms
Vertigo is a rotating sensation when stationary. Usually associated with nausea or vomiting, instability (postural instability), falls, changes in one's mind, and difficulty in walking. Recurrent episodes in vertigo sufferers often occur and often interfere with quality of life. Blurred vision, speech impairment, low awareness, and hearing loss can also occur. Signs and symptoms of vertigo may appear as an onset of persistent (insidious) or episodic onset (sudden).
A persistent onset of vertigo is characterized by symptoms lasting more than a day and is caused by degenerative changes that affect balance as we get older. Naturally, nerve conduction slows down with aging and the reduced vibration sensation is common. In addition, there is degeneration of ampullary organs and otolith with increasing age. Persistent onset is generally paired with signs and symptoms of central vertigo.
The characteristic of episodic onset vertigo is shown by symptoms that last for smaller amounts of time, more impressive, usually lasting only a few seconds to minutes. Typically, episodic vertigo is correlated with peripheral symptoms.
Pathophysiology
Neurochemistry vertigo includes six major neurotransmitters that have been identified between three-neuron arcs that induce vestibulo-ocular reflex (VOR). Glutamate maintains the discharge from the central vestibular neuron, and can modulate the synaptic transmission in all three neurons from the VOR arc. Acetylcholine appears to function as a stimulating neurotransmitter in both the periphery and central synapses. Gamma-Aminobutyric Acid (GABA) is considered inhibition for commissures of the medial vestibular nucleus, the connection between Purkinje cerebellar cells, and lateral vestibular nuclei, and vertical VOR.
Three other neurotransmitters work centrally. Dopamine can speed up vestibular compensation. Norepinephrine modulates the intensity of the central reaction to vestibular stimulation and facilitates compensation. Histamine is only present centrally, but its role is unclear. Dopamine, histamine, serotonin, and acetylcholine are neurotransmitters that allegedly produce vomiting. It is well known that centrally acting antihistamines modulate symptoms of acute symptomatic vertigo.
Diagnostic approach
Tests for vertigo often try to get nystagmus and to distinguish vertigo from other causes of dizziness such as presyncope, hyperventilation syndrome, disequilibrium, or the cause of psychological headaches. Vestibular system function tests include: electronystagmography (ENG), Dix-Hallpike maneuver, rotation test, head prick test, calorie reflex test, and computerized dynamic posturography (CDP).
The HINTS test, which is a combination of three physical examinations that can be performed by a doctor at the bedside has been considered helpful in distinguishing between the central and peripheral causes of vertigo. HINTS tests include: a horizontal head impulse test, nistagmus observation in primary gaze, and a skewed test. CT scans or MRIs are sometimes used by doctors when diagnosing vertigo.
Hearing system test (auditory) functions include pure tone audiometry, speech audiometry, acoustic reflex, electrokochleography (ECoG), otoacoustic emissions (OAE), and hearing brainstem response tests.
Certain conditions may cause vertigo. However, in the elderly, the condition is often multifactorial.
Recent underwater dive histories may indicate the possible involvement of barotrauma or decompression disease, but do not rule out all other possibilities. Dive profiles (often recorded by dive computers) can be useful for assessing the likelihood of decompression disease, which can be confirmed by therapeutic recompression.
Vertigo positional paroxysmal benign
Benign paroxysmal positional vertigo (BPPV) is the most common vestibular disorder and occurs when loose calcium carbonate debris has broken off the autoco- rial membrane and enters the semicircular canal thus creating a motion sensation. Patients with BPPV may experience a short vertigo period, usually less than a minute, occurring with a change of position.
This is the most common cause of vertigo. This occurs in 0.6% of the population each year with 10% experiencing attacks during their lifetime. It is believed to be caused by mechanical damage to the inner ear. BPPV can be diagnosed with a Dix-Hallpike test and can be effectively treated with repositioning movements such as the Epley maneuver.
Diseases MÃÆ' Â © niÃÆ'¨re
Disease MÃÆ' Â © niÃÆ'¨re is an unknown inner ear disorder, but is thought to be caused by an increase in the amount of endolymphatic fluid present in the inner ear (hydrops endolymphatic). However, this idea has not been confirmed directly with histopathological studies but electrophysiological studies have demonstrated this mechanism. MÃÆ' Â © niÃÆ'¨re disease often presents with severe recurrent vertigo severe attacks in combination with ringing in the ears (tinnitus), feelings of pressure or fullness of the ear (fullness of aural), severe nausea or vomiting, imbalance, and hearing loss. As the disease worsens, hearing loss will continue.
Labyrinthitis
Labyrinthitis presents with severe vertigo with nausea, vomiting, and general imbalances and is believed to be caused by viral infection of the inner ear although several theories have been advanced and the cause is uncertain. Individuals with vestibular neuritis usually have no hearing symptoms but may experience aural aural sensation or tinnitus. Persistent balance problems may persist in 30% of people affected.
Migraine vestibular
Vestibular migraine is a link between vertigo and migraine and is one of the most common causes of recurrent episodes of spontaneous vertigo. The cause of current vestibular migraine is unclear; However, one cause of the hypothesis is that trigeminal nerve stimulation causes nystagmus in individuals who suffer from migraine.
Other suggested causes of vestibular migraine include the following: unilateral nerve instability of the vestibular nerve, idiopathic asymmetric activation of the brainstem vestibular nucleus, and vascular vasospasm supplying the labyrinth or central vestibular pathway resulting in ischemia in this structure. Vestibular migraine is thought to affect 1-3% of the general population and can affect 10% of migraine patients. In addition, vestibular migraine tends to occur more frequently in women and rarely affects individuals after the sixth decade of life.
Motion sickness
Motion sickness is common and is associated with vestibular migraine. Nausea and vomiting in response to movement and usually worse if the trip is on a winding road or involves many stops and starts or if the person is reading in a moving car. This is due to a mismatch between visual input and vestibular sensation eg the person is reading a book that is silent in relation to the body but the vestibular system senses that the car, and thus the body, moves.
Alternobaric vertigo
Vertigo was recorded as a symptom of decompression disease in 5.3% of cases by the US Navy as reported by Powell, 2008 This includes isobaric decompression disease.
Decompression can also be caused at constant ambient pressure when switching between gas mixtures containing different inert gas proportions. This is known as isobaric counterdiffusion, and presents a problem for deep diving. For example, after using a very rich trimix helium in the deepest part of the dive, the diver will switch to a mixture containing a little helium and more oxygen and nitrogen during the climb. Nitrogen diffuses into tissues 2.65 times slower than helium, but about 4.5 times easier to dissolve. The shift between gas mixtures that have very different nitrogen and helium fractions can produce "fast tissue" (tissue that has a good blood supply) actually increases the total loading of inert gas. This is often found to provoke decompression of the inner ear, because the ears appear to be very sensitive to this effect.
Stroke
Stroke (either ischemic or hemorrhagic) involving the posterior fossa is the cause of central vertigo. Risk factors for stroke as a cause of vertigo include increased age and known vascular risk factors. Presentations may more frequently involve headache or neck, in addition, those who have some episodes of dizziness in the months leading up to presentation are suggestive of stroke with TIA prodromal. The HINTS exam as well as brain imaging studies (CT, CT angiogram, and/or MRI) are helpful in the diagnosis of posterior fossa stroke.
Management
The definitive treatment depends on the cause of vertigo. Patients of MÃÆ' Â © niÃÆ'¨re disease have a wide range of treatment options to consider when receiving treatment for vertigo and tinnitus including: low-salt diet and intratympanic injection of gentamicin antibiotics or surgical measures such as shunt or labyrinth ablation in refractory cases. The common treatment options for vertigo may include the following:
- Anticholinergics such as hyoscine hydrobromide (scopolamine)
- Anticonvulsants such as topiramate or valproic acid for vestibular migraine
- Antihistamines such as betahistine, dimenhydrinate, or meclizine, which may have antiemetic properties
- Beta blockers such as metoprolol for vestibular migraine
- Corticosteroids such as methylprednisolone for inflammatory conditions such as vestibular neuritis or dexamethasone as second-line agents for disease MÃÆ'Â © niÃÆ'¨re
All cases of decompression disease should be treated initially with 100% oxygen until hyperbaric oxygen therapy (100% oxygen delivered in high pressure chamber) can be provided. Some treatments may be needed, and treatment will generally be repeated until all symptoms recover, or no further improvement.
Etymology
Vertigo comes from the Latin word vert? which means "spinning or spinning motion".
See also
References
External links
Source of the article : Wikipedia
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