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.• Sudden onset of vertigo is due to asymmetry of vestibular system dysfunction.• Approximately half of patients presenting with dizziness have true vertigo.• Establish the onset of problem, and whether it is acute, subacute, or chronic.• Vertigo is usually paroxysmal.Constant vertigo suggests psychogenic and not vestibular dysfunction.Chronic conditions such as acoustic neuroma rarely present with vertigo.• Aggravating factors can be head or body position.• Benign positional vertigo accounts for about half of all cases of vertigo.• Associated symptoms: nausea, vomiting, fullness of ears, hearing loss, tinnitus, all of which suggest otological etiologies; headaches, diplopia, blurred vision, ataxia, paresthesia, all suggestive of central nervous system (CNS) etiologies.• History of recent ear or upper respiratory infection or head trauma.• History of drug regimen or drug overdose.• History of depression or other psychiatric problems.• Vertigo that is provoked by exertion, loud noise, sneezing, or coughing (Tullio’s phenomenon) is suggestive of perilymphatic fistula.KEY POINTS OF PHYSICAL EXAMINATION• Check cardiovascular system for cardiac arrhythmia, murmur, orthostatic hypotension, and carotid or subclavian bruits.• Check ear for infection, trauma, or impacted wax.• Do Nylen-Barany (Dix-Hallpike) test: Have the patient, from seating position on the table, quickly lie down supine with head positioned 45° over the From: Current Clinical Neurology:Practicing Neurology: What You Need to Know, What You Need to Do By: R.Pourmand © Humana Press Inc., Totowa, NJ111112Practicing Neurologyend of the table, and then rotate the head 45° side to side (for 30 seconds).Observe for vertigo, nausea, and nystagmus (onset, direction, and duration); presence of these symptoms/signs is suggestive of vestibulopathy if they have delayed onset, and are fatigable and unidirectional.Nystagmus in vestibulopathy is upbeat and torsional and resolves with eye fixation.• Complete neurological examination, with special attention to brainstem, cranial nerves, and cerebellar function, stance, and gait.CAUSES OF VERTIGOVertigo is a multifactorial condition.The neurologist is often consulted to differentiate whether vertigo is caused by inner ear disease (vestibulopathy) or CNS lesion.Keep in mind migraine as a possible cause of vertigo in a young adult.SYMPTOMS AND SIGNS OF CNS CAUSES1.The onset could be acute, subacute, or chronic.2.When doing the head-tilt test or Nylen-Barany test, the onset of vertigo is sudden, without any latency or delay and it does not fatigue (decrease severity with repetition of tilt).Vertigo persists as long as head is kept tilted.3.Nystagmus is often multidirectional.4.Nausea/vomiting, generalized fatigue, and hearing loss is less severe.5.Associated neurological symptoms and signs (brainstem/cerebellar dysfunction) are further supportive of CNS causes.SOME CNS CAUSES OF VERTIGO• Posterior circulation transient ischemic attacks or stroke.• Brainstem stroke or tumor.• Cerebellopontine angle tumors.• Posterior fossa pathologies.• Multiple sclerosis.• Spinocerebellar degeneration.• Migraine variant.CAUSES OF DRUG-INDUCED DIZZINESS ANDVERTIGO• Aminoglycosides.• Penicillin.• Aspirin.• Sulfonamide.• Antiepileptic drugs.• Antihistamines.Dizziness and Vertigo113SOME COMMON OTOLOGICAL CAUSES OF VERTIGOBenign Paroxysmal Positional Vertigo• Benign paroxysmal positional vertigo is the most common cause of acute vertigo.• Characteristically presents with recurrent episode of vertigo, lasting seconds to minutes, aggravated by head position, particularly rolling over in bed.• Hearing is intact and rarely does tinnitus occur.• It is thought to be caused by calcium deposit in the posterior semicircular canal (canalithiasis) after head trauma or repeated ear infection.• Although generally self-limited, the condition is disabling at times.Acute Labyrinthitis or Vestibular Neuronitis• Acute vestibular neuronitis or labyrinthitis causes more severe and prolonged duration of vertigo, associated with nausea and vomiting and, occasionally, hearing impairment and tinnitus.• Usually preceded by upper respiratory tract infection.It is usually self-limited.• Some experts recommend a course of methylprednisolone to prevent hearing loss.WORKUP OF DIZZY PATIENTWorkup depends upon the suspected etiology, after history and examination.If the patient has hearing loss and tinnitus, and is suspected of having otological disease, the patient should be evaluated by an ear, nose, and throat specialist for a formal audiogram and caloric testing.If CNS causes are suspected, magnetic resonance imaging of the head is indicated.Dizziness of undetermined etiology should be tested for complete blood count, erythrocyte sedimentation rate, chemistry profile, electrocardiogram, thyroid function test, and fluorescent treponemal antibody test.Electronystagmography and brainstem auditory evoked response have limited use.SYMPTOMATIC DRUG THERAPY FOR DIZZINESS1.Anticholinergic.Scopolamine disk (Transderm-Scop): 1.5 mg/disk behind the ear, or 0.5–1 mg, three times a day orally.2.Antihistamines.Meclizine hydrochloride (Antivert): 25–100 mg/day in divided dose, or dimenhydrinate (Dramamine): 50 mg four times a day.3.Antiemetics.Promethazine hydrochloride (Phenergan): 50–100 mg/day in divided dose, or metoclopramide.4.Benzodiazepines.Diazepam or lorazepam.5.Diuretics.Hydrochlorthiazide: 50 mg/day.114Practicing NeurologyCaveat: All above medications except diuretics have sedation effects, and they should be used only when necessary, such as for frequent and severe symptoms.The response to pharmacotherapy is generally unrewarding.Vestibular exercise—inducing vertigo by repeating the position to produce adaptation—is effective in treating mild vertigo (Brandt-Daroff exercise).For benign paroxysmal positional vertigo, the most effective treatment is repositioning maneuvers such modified Epley and Semon maneuvers.15Headaches and Facial PainHEADACHESEvaluation of the Patient With HeadacheHistory: Obtaining a careful and thorough history of the headache is the most important part of the evaluation.You should establish the following as you are taking the history:• Age at onset of headache.• Onset of headache: whether it is acute, subacute, or chronic.• Severity and frequency of the headache.• Characteristics of the pain as described by the patient.• Location and duration of the headache.• Any associated symptoms or signs.• What the aggravating or relieving factors are.• Have there been any recent changes of headache type?• Any relation to menstrual period or season?• How often are medications used or how was the response to previous treatment?Social history: occupation, marriage, history of alcohol or drug abuse.Family history: Very important; about 50% of patients with migraine have a positive family history.Medical history: history of hypertension, depression, glaucoma.Medication history: contraceptives, diet control pills, or medications that have been used for headaches.Physical and Neurological ExaminationExamine the head and neck, record blood pressure, and check peripheral and temporal arteries pulses.With any new patient, a complete neurological examination is mandatory.Special attention is particularly given to the neck for stiffness, bruits, fundoscopy examination, pupillary size and reactions, visual field, cranial nerves, and any focal neurological signs.From: Current Clinical Neurology:Practicing Neurology: What You Need to Know, What You Need to Do By: R.Pourmand © Humana Press Inc [ Pobierz całość w formacie PDF ]