Vertigo/Dizziness Flashcards
The Vestibular system is divided into ?
The vestibular system is broadly categorized into both peripheral and central components. The peripheral system is bilaterally composed of three semicircular canals (posterior, superior, lateral) and the otolithic organs (saccule and utricle). The semicircular canals detect rotational head movement while the utricle and saccule respond to linear acceleration and gravity, respectively
> What is the distinction between Meniere’s Disease and Meniere’s Syndrome? And what is the pathophysiology?
> What are the symptoms
> What is Rx?
> Meniere’s Disease is idiopathic Endolymphatic hydrops.
Endolymphatic Hydrops is increase in endolymphatic pressure resulting in inappropriate nerve excitation which gives rise to the symptom complex of vertigo, fluctuating hearing loss, and tinnitus.
. >Numerous disease processes can result in endolymphatic hydrops; if there is a known etiology then it is termed MENIERE’S SYNDROME.
> SYMPTOMS: Typically, these patients complain of SPONTANEOUS EPISODIC ATTACKS OF TINNITUS, AURAL FULLNESS, FLUCTUATING HEARING LOSS, AND VERTIGO SUPERIMPOSED ON A GRADUAL DECLINE IN HEARING. SYMPTOMS are variable, however, and patients may have a predominance of either cochlear (tinnitus, hearing loss) or vestibular (vertigo) complaints. ATTACKS TYPICALLY LAST MINUTES TO HOURS; HOWEVER, MOST COMMONLY SUBSIDE AFTER 2 TO 3 HOURS.
TREATMENT: Medical treatment is initiated prior to more invasive surgical intervention and consists of salt restriction, diuretics, vasodilators, anti-emetics, and anti-nausea medications. Those who fail medical treatment may consider surgical therapy
> What is the second most common cause of vertigo?
> Etiology?
> Symptoms?
> Vestibular Neuronitis
> Infection of the vestibular nerve results in nerve degeneration and may present bilaterally. Infection is most often thought to be of viral origin, usually from the HERPES VIRUS FAMILY. It may also result from bacterial invasion (e.g. BORRELIA). It is believed that the superior vestibular nerve is more commonly involved secondary to its course throughout a long and narrower bony canal, making it more susceptible to COMPRESSIVE EDEMA. The reported incidence of an upper respiratory infection prior to the development of vestibular symptoms varies from 23% to 100%
> Patients present with complaints of sudden vertigo, lasting up to several days, often with vegetative symptoms. As this process affects only the vestibular portion of the vestibulocochlear apparatus, there is an absence of cochlear symptoms. Vertiginous complaints gradually improve over days to weeks; however, imbalance may persist for months after resolution of acute disease. Recurrence is not uncommon and may occur several times per year. Physical examination is limited and should consist of audiometric evaluation and ENG. Patients may demonstrate nystagmus and caloric weakness on the affected side.
Treatment is primarily supportive with the use of anti-emetics and anti-nausea medications. VESTIBULAR SUPPRESSANTS SHOULD BE USED JUDICIOUSLY IN THE FIRST FEW DAYS OF AN ACUTE ATTACK. PROLONGED USE OF THESE MEDICATIONS CAN DELAY RECOVERY BY INHIBITING CENTRAL COMPENSATION. FURTHERMORE, EARLY AMBULATION IS PARAMOUNT IN the central nervous system’s ability to compensate and is therefore recommended as soon as tolerable. High-dose METHYLPREDNISOLONE HAS BEEN SHOWN TO HASTEN RECOVERY(Treatment with methylprednisolone (22-day tapering dose schedule) significantly improved vestibular function at 12-month follow-up compared with placebo)**Some studies suggest that corticosteroids HASTEN THE RECOVERY BUT THAT DOESN’T CHANGE THE LONG TERM PROGNOSIS*DESPITE these somewhat conflicting results and remaining questions, it seems reasonable to treat presumed viral acute labyrinthitis with corticosteroid therapy. WE TYPICALLY PRESCRIBE A 10-DAY COURSE OF PREDNISONE; 60 MG DAILY ON DAYS ONE THROUGH FIVE, 40 MG ON DAY SIX, 30 MG ON DAY SEVEN, 20 MG ON DAY EIGHT, 10 MG ON DAY NINE, AND 5 MG ON DAY 10.
THERE IS NO EVIDENCE THAT ANTIVIRAL MEDS LIKE VALACYCLOVIR HELP
> What Peripheral causes of Vertigo causes vertigo with exposure to loud noises?
> PERILYMPHATIC FISTULA AND SUPERIOR SEMICIRCULAR CANAL DEHISCENCE SYNDROME
A perilymphatic or inner ear fistula results from an abnormal communication between the perilymphatic space and middle ear or an intramembranous communication. There are numerous causes, stapedectomy most commonly, and also head trauma, explosive blast, barotrauma, and physical exertion.
What is the difference between Labyrinthitis and Vestibular Neuritis(or Neuronitis)?
-They both are caused most often by a viral illness but in Vestibular Neuronitis there is no hearing loss.
Patients with labyrinthitis typically present with severe room-spinning vertigo and associated nausea and vomiting. They may also have hearing loss and tinnitus (ringing in the ear). The hearing loss is sensorineural (i.e., related to inner ear/eighth cranial nerve) rather than conductive (i.e., secondary to middle ear causes). The acute vertigo may last up to 72 hours. Acute vertigo is typically followed by persistent disequilibrium, imbalance, and brief vertigo (seconds) with quick head or body movements.
1-What causes of vertigo last minutes to several hours?
2-What causes of vertigo are of sudden onset and last days to weeks?
3-What cause of vertigo last days but the disequilibrium
can persist for weeks ?
1-Menier’s Diseased
- Vertebrobasilar TIA
- Vestibular Migraine
2-Cerebellar Infarction and hemorrhage
-Brainstem Infarction
3-Vestibular Neuronitis and Labyrinthitis(of viral origin)
What is the difference in Nystagmus between peripheral causes and central causes?
- Peripheral characteristics of nystagmus: horizontal or horizontal-torsional; suppresses with visual fixation, does not change direction with gaze.
- Central characteristics of nystagmus: may be horizontal, torsional, or vertical, does not suppress with visual fixation, may change direction with gaze.
