Dizziness and Vertigo Dr. Anirban Biswas Neurotologist, Vertigo and Deafness Clinic, Kolkata Introduction Good balance is an imperative skill for sustenance of daily life that requires the complex integration of sensory information regarding the position of the body relative to the surroundings and the ability to generate appropriate motor responses to control body movement and stabilize posture and gaze. Gaze stabilization is as important as stabilization of posture. If there is a defect in gaze stabilization, the surroundings appear to be moving with the subject and feels like vertigo. If there is a defect in postural stability, subject gets the feeling of imbalance or instability. Balance calls upon contributions from vision, vestibular sense (i.e., the sensation from the balance organ in the ears), proprioception, musculoskeletal coordination, and even cognitive skills. Like all the body reflexes, the reflex system that controls balance has a sensory organ (the eyes/vestibular labyrinth in the ears/ proprioceptors in the soles of the feet, back and buttocks) that senses the stability of the ground and the surroundings. An afferent pathway carries the sensation to the centre of the reflex in the vestibular 3 nuclei of the brainstem. An afferent motor pathway are neural pathways or nerves that carry the motor output in the form of neural impulses to the effector motor organs, which are the muscles of the limbs/trunk for stabilization of posture and to the muscles of the eyes for stabilization of gaze. With advancing age, there is a progressive loss of functioning of all these systems, which can contribute to balance deficits. Balance disorders represent a growing public health concern due to the association with falls and fall-related injuries, particularly in regions of the world in which high proportions of the population are elderly. The major functional objectives of the balance system aret a)Maintenance of clear and very distinct image of the surrounding visual field with the head in motion, the surrounding objects in motion, or both the head and the surrounding objects in relative motion. Objects in the surroundings should not appear to be rotating or spinning if they are not actually spinning/rotating. Stable objects should appear fixed and stable in the visual environment. b) Perceptions of orientation relative to gravity like going up or down in a lift, perceiving the direction and speed of movement, and when a change in the speed or direction of movement takes place. c) The ability to maintain static and dynamic upright stance, and to perform volitional movements ranging from routine ambulation to complicated balance tasks involved in activities like playing 4 tennis, badminton, cycling, skiing, dancing, tight rope walking, walking on a fence, etc. Classification of balance disorder1: • Sensory factors affecting balance: ⊲Vision ⊲ Vestibular sense ⊲ Proprioception ⊲ Sensory integration • Motor system factors affecting balance: ⊲Strength ⊲ Reaction time i.e., the time taken for the reflex contraction of the muscles of the body/eyes after the sense organs have perceived a movement Dizziness Dizziness is a general term used for a sense of disorientation. Diagnosing the cause of dizziness can be difficult because symptoms are often non-specific and the differential diagnosis is broad. However, a few simple questions and physical examination tests can narrow the possible diagnosis. It is estimated that primary care physicians treat more than 50% of all patients who present with dizziness. Dizziness is the chief presenting symptom in about 3% of primary care visits 5 for patients aged 25 years and older, and in nearly 3% of all emergency department visits. Dizziness can be classified into four main types viz., vertigo, disequilibrium, pre-syncope and lightheadedness (Table 1).2 Category Description Percentage of patients with dizziness Vertigo False sense of motion, possibly spinning sensation 45–54 Disequilibrium Off-balance or wobbly or instability Up to 16 Pre-syncope Feeling of losing consciousness or blacking out or a sinking sensation Up to 14 Lightheadedness Vague symptoms, possibly feeling disconnected with the environment/disorientation Approx. 10 Table 1: Main categories of dizziness2 Causes of dizziness2 Dizziness may be attributed by a wide variety of causes. Some of the causes are of sinister significance and can be life threatening, and therefore require immediate medical attention. Some causes are trivial self-limiting disorders that need to be managed just by providing symptomatic relief for a few days. The problem is that, the presentation is the same irrespective of whether it is a life-threatening condition or any self-limiting benign disorder. Selected causes, category and diagnostic criteria are listed in Table 2. 6 Causes Category of dizziness Diagnostic criteria from history Benign paroxysmal positional vertigo Vertigo Positive findings with Dix–Hallpike test; episodic vertigo for a few seconds only on change of head position, without hearing loss Hyperventilation syndrome Lightheadedness Symptoms reproduced with voluntary hyperventilation Ménière’s disease Vertigo Episodic vertigo with hearing loss/aural fullness/tinnitus Migrainous vertigo (vestibular migraine) Vertigo Episodic vertigo with signs of migraine, plus photophobia, phonophobia, or aura during at least two episodes of vertigo; some will have history of typical migraine headache, not all 7 Orthostatic hypotension Pre-syncope Decrease of systolic blood pressure by 20 mm Hg; decrease of diastolic blood pressure by 10 mm Hg; or increase of pulse by 30 bpm on sudden standing Parkinson’s disease Disequilibrium Shuffling gait with reduced arm swing and possible hesitation; typical dull emotionless face Peripheral neuropathy Disequilibrium Decreased sensation in lower extremities, particularly the feet Table 2: Selected causes of dizziness 8 Patients presents with dizziness Ask about medication regimen; caffeine, nicotine, and alcohol intake; and history of head trauma or whiplash What sensation on dose the patient describe? False sense of motion or spinning sensation Vertigo Ask about migraine symptoms Migrainous vertigo is diagnosed with history of episodic vertigo with a current migraine or history of migraine and one of the following symptoms during at least two episodes of vertigo: migraine headache, photophobia, phonophobia, aura Off-balance or wobbly Dysequilibrium Pre-syncope Consider possible underlying conditions, Ask about history of arrhythmias such as peripheral and myocardial neuropathy and infarction Parkinson’s disease Lightheadedness Ask about history of anxiety or depression Re-check medication Re-check medication Perform regimen, especially in regimen, especially hyperventilation older patients in older patients provocation test Examine gait and vision, Measure perform Romberg’s test, orthostatic blood screen for neuropathy pressures Consider cardiac testing in patients with relevant history Hearing loss? No Yes Episodic vertigo? Yes Feeling of losing Vague symptoms, consciousness or possibly feeling blacking out disconnected with the environment No Episodic vertigo? Yes Ménière’s Labyrinthitis Benign paroxysmal disease positional vertigo No Vestibular neuritis Perform Dix–Hallpike maneuver Table 3: Algorithm for the initial evaluation of a patient with dizziness2 9 Vertigo Vertigo is a sub-type of dizziness, which results from a disparity in the electrical discharge in between the left and right vestibular labyrinths. Vertigo is a spinning sensation, and in medical parlance is defined as an illusion of rotational motion. Physiology of vertigo3 Most vertigo is caused by dysfunction of the vestibular labyrinth(s) of the inner ear, which houses the rotational velocity sensors. In the normal situation, individuals continuously process three types of sensory inputs: vestibular (inner ear), visual and somatosensory/ proprioceptive. These three streams of information from the sides of the body as well as from the front and back are combined or integrated in the central vestibular apparatus in the brain to assess the stability of the ground and the surroundings, and thereby form an estimate of orientation and motion of the head and body. Asymmetrical or defective input into the central vestibular apparatus (that is the central nervous system) or asymmetrical central processing leads to physiological and pathological vertigo. In disorders of the vestibular labyrinth, which will be resulted by various causes like inflammatory, degenerative, neoplastic, vascular or infective, the input from one or both vestibular labyrinths in the central nervous system is either symmetrical or sub-normal. Neurochemistry of vertigo There are at least six neurotransmitters of the vestibular system involved in the three-neuron arc between the vestibular hair cells and 10 oculomotor nuclei that drive the vestibulo–ocular reflex (see Table 4). There are also a host of other neurotransmitters that modulate function or involved in a more minor way. Neurotransmitter Peripheral role Central role Glutamate Excitatory Excitatory Acetylcholine Excitatory for efferent synapse Excitatory GABA Unclear Inhibitory Dopamine Excitatory Noradrenaline (norepinephrine) Modulator Histamine Unclear Table 4: Neurotransmitters of the vestibular system A lot of current medication in the management of vertigo consists of modulating the excitatory or inhibitory effects of the neurotransmitters. 11 Classification of vertigo Based on Based on site Prolonged vertigo usually a Otomastoiditis Central vertigo Peripheral vertigo Vestibular neuronitis Labyrinthine concussion Lateral medullary infarction Cerebellar infarction Recurrent episodes of vertigo Ménière’s syndrome Auto-immune inner-ear disease Perilymph fistula Migraine-related vertigo Benign positional paroxysmal vertigo Vertebrobasilar insufficiency 12 Etiology of vertigo4 Vertigo related to the inner ear (vestibular labyrinth – semicircular canals/otolith organs viz., uticle and saccule) may be caused by: • Benign paroxysmal positional vertigo • Drugs such as aminoglycoside antibiotics, cisplatin, diuretics, or salicylates • Injury (such as head injury) Infections Epilepsy Diseases of blood vessels Multiple sclerosis Trauma Middle ear: otitis media Tumors Labyrinthitis, Ménière’s disease Medicines Fig. 1: Possible causes of vertigo Adapted from Netter. 13 •Labyrinthitis •Ménière’s disease • Perilymph fistula Vertigo related to disorders of vestibular nerve may be caused by: • Inflammation (neuronitis) • Pressure on the vestibular nerve (most often due to a non-cancerous tumor such as a meningioma or schwannoma, commonly called as acoustic neuroma) • Effect of some drugs like oral contraceptives • Trauma to the nerve as in transverse fracture of the temporal bone usually after traffic accidents Vertigo related to the brainstem may be caused by: • Blood vessel disease • Drugs (anti-convulsants, aspirin, alcohol) • Migraine • Multiple sclerosis • Seizures (rarely) Central vs peripheral vertigo • Peripheral vertigo occurs if there is a problem with the part of the inner ear that controls balance (vestibular labyrinth) or with the vestibular nerve, which connects the inner ear to the brainstem. 14 • Central vertigo occurs if there is a problem in the brain, particularly in the brainstem or the cerebellum. Central vertigo Intermediate vertigo Peripheral vertigo Fig. 2: Sites of vertigo 15 Clinical history (in addition to vertigo, nausea, and vomiting) Otomastoiditis Previous ear infections, otorrhea, ear pain, hearing loss Examination (in addition to nystagmus and imbalance) Management (in addition to treatment of symptoms) Otitis media, tympanosclerosis, cholesteatoma, granuloma Vestibular neuritis No other clinical findings other than nystagmus, positive findings in some of the clinical neurotological steps like stepping test Antibiotics, surgical removal of infected tissue/ cholesteatoma, vestibular rehabilitation Brief course of high-dose steroids, vestibular rehabilitation Labyrinthine concussion 16 Previous influenza-like symptoms, acute onset of severe vertigo persisting for 1–3 days, no hearing loss Onset after blow to head, hearing loss and tinnitus, symptoms of brain concussion Hearing loss, possible blood or CSF in ear canal Vestibular rehabilitation Lateral medullary infarction Vascular Ipsilateral Horner’s Control of risk factors, syndrome, facial vascular risk sudden numbness, lack factors onset, facial of coordination, numbness decreased gag and reflex, contralateral weakness, numbness in limbs diplopia, dysphagia, lateropulsion Cerebellar Cardiac Truncal ataxia, limb Control infarction disease, ataxia, or both of source vascular of emboli, risk factors, other risk sudden onset, factors, gait profound and balance imbalance, training possible lack of limb coordination Table 5: Common causes of prolonged non-episodic vertigo3 17 Clinical history (in addition to vertigo, nausea, and vomiting) Ménière’s Fluctuating syndrome hearing loss, ear fullness, roaring tinnitus, rarely sudden falls (otolithic crises) Autoimmune Fluctuating inner-ear or slowly disease progressive hearing loss, possible systemic symptoms of autoimmune disease Perilymph “Popping” sound, fistula hearing loss, or tinnitus after head trauma, barotrauma, cough, sneeze, straining 18 Examination (between attacks) Lowfrequency hearing loss (unilateral in most cases) Management (in addition to treatment of symptoms) Low-salt diet, diuretics, surgery only for intractable but confirmed cases Hearing loss (bilateral in many cases), interstitial keratitis, arthritis, rash High-dose steroids Possible positive fistula sign (nystagmus induced by pressure change in external ear canal) Bed rest, avoidance of straining, exploratory tympanotomy for fistula if symptoms persist Migraine Headache, visual aura, unilateral numbness, motion sensitivity dysphagia, lateropulsion Normal in most cases Vertebrobasilar insufficiency Visual loss, diplopia, ataxia, dysarthria, numbness, weakness Normal in most cases β-blockers, calcium-channel blockers, tricyclic antidepressants Anti-platelet drugs (aspirin 75–330 mg daily, ticlopidine 500 mg daily), anti-coagulation for severe progressive symptoms Table 6: Common causes of recurrent attacks of vertigo3 19 Vestibular neuritis (vestibular neuronitis) Vestibular neuronitis/neuritis is the second common cause of vertigo seen in peripheral labyrinthine disorders. It occurs due to viral/ bacterial inflammation of the vestibular nerve, and usually follows an upper respiratory tract infection. The onset of vertigo, usually with nausea, and vomiting but without any ear-related symptoms like deafness/tinnitus/aural fullness in vestibular neuritis is typically acute, over minutes to hours. Symptoms usually peak within 1–6 h and resolve slowly over 2–3 days, but may sometimes continue for about a week. During the first day, the patient has severe truncal unsteadiness and imbalance, and has difficulty in focusing the eyes because of spontaneous nystagmus. The course is usually benign, with complete recovery in 4–6 weeks. Recovery of the presenting symptoms of vertigo with nausea and vomiting occurs spontaneously in most cases even when the unilateral loss of vestibular function is permanent because the brain compensates for the vestibular loss. There are exceptions, particularly in older patients and the ill patients who will be taking the symptom relieving and the vertigo drugs for a prolonged period, in which compensation may be slow or incomplete. Vestibular neuritis is thought to have a viral origin, but proof in an individual case is difficult. MRI with contrast enhancement occasionally reveals an inflammation of the 8th cranial nerve, but these findings are non-specific and have little diagnostic value. Serological studies may show a viral infection but cannot prove that a virus has caused the inner ear damage. Vestibular neuritis is different from Ramsay Hunt syndrome, which is also a viral inflammation of the vestibulo–cochlear 20 nerve that is caused by varicella zoster virus. In this disease, visible eruptions are quite often seen in the external auditory meatus along with facial paralysis and hearing loss, none of which are present in vestibular neuritis. In Ramsay Hunt syndrome, patients typically have a deep burning pain in the ear, which is never seen in vestibular neuritis. Ménière’s syndrome3 In 1861, Prosper Ménière first described the triad of fluctuating hearing loss, tinnitus, and episodic vertigo. This is the hallmark of Ménière’s syndrome even today, and the diagnosis of Ménière’s disease is based on this typical presentation, where the patient will have recurrent episodes of vertigo, which will last for anything between 21 half an hour and 12 h, and rarely a little more but definitely less than a day, along with ear-related symptoms like deafness, tinnitus, and a fullness of one ear. In between two attacks of vertigo, the patient does not have any significant imbalance or any vertiginous sensation, but some ear-related problems like deafness and tinnitus are usually persistent. The ear-related symptoms of an aggregate is observed just prior to or during the episode of vertigo. Patients with Ménière’s syndrome have different symptoms, in different stages Endolymphatic sac Endolymphatic duct Utricle Saccule Stapes Fig. 3: Engorged endolymphatic compartment of the inner ear in Ménière’s disease Adapted from Hain and Uddin. 22 of the disease. Diagnosis is difficult, particularly in the early stages and remains uncertain in the first one or two attacks of vertigo as the ear-related symptoms may not be apparent in the very early stages. By definition, Ménière’s disease can be diagnosed without the combination of fluctuating hearing loss and vertigo. Simply recurrent attacks of vertigo even if episodic cannot be labeled as Ménière’s disease, if there is no ear-related symptoms. Delayed Ménière’s syndrome can develop in an ear that has been damaged years before, usually by a viral or bacterial infection. Patients with this type of Ménière’s syndrome report a long history of hearing loss sometimes since early childhood, followed many years later by episodes of vertigo. In such cases hearing loss is generally profound, and the vertigo is not accompanied by fluctuating hearing loss and tinnitus. Though the disease is primarily diagnosed from its typical presentation as described above, yet for confirmation certain investigations need to be done namely video-nystagmography, pure tone audiometry with glycerol test and other localizing tests, brainstem-evoked response audiometry, and electrocochleography. Imaging studies like an MRI of the brain or inner ear does not help even though it is not unwise to have an imaging study done to rule out an acoustic neuroma, which can also be present with vertigo and deafness with tinnitus. However, in an acoustic neuroma, there is practically never an episodic vertigo as is present in Ménière’s disease. The main pathological finding in patients with Ménière’s syndrome is an increase in the volume of endolymph, associated with distension of the entire endolymphatic system (endolymphatic hydrops). The episodes of hearing loss and vertigo may be caused by ruptures in the membranes separating endolymph from perilymph, which lead to 23 a sudden increase in potassium concentration in the perilymph. Another possible explanation for the fluctuating symptoms is mechanical deformation of the end organ, which is reversible as the endolymphatic pressure decreases. The incidence of sudden falling are probably due to sudden distension and deformation of one of the otolith organs. Healthy inner ear: Balance canal Endolymphatic sac Hearing and balance nerve Hearing canal Ménière’s disease: Backed-up fluid leads to swelling and pressure Swelling distorts balance information Swelling distorts sound information 24 Distorted information travels to brain Benign paroxysmal positional vertigo4 Patients with benign paroxysmal positional vertigo (BPPV) develop brief episodes of vertigo with position change, typically when turning over in bed, getting in and out of bed, or extending the head back to look upwards or even downwards. Typically, the spinning sensation occurs just for a few seconds to less than a minute. The diagnosis is easily made from the typical history, and confirmed by identification Posterior semicircular canal Utricle Vestibule Cupulolithiasis, debris attached to cupula Canalithiasis, debris in posterior canal Fig. 4: Canalolithiasis mechanism of benign paroxysmal positional vertigo (Adapted from Hain and Uddin.) 25 of the characteristic torsional nystagmus after the patient is moved from the sitting to the sideward – head hanging position (the Dix–Hallpike test). This type of vertigo can occur in otherwise perfectly normal ears with normal vestibular function be it a sequelae of head trauma or vestibular neuritis. Migrainous patients are very susceptible to BPPV, and the incidence of this disorder is quite high in patients with migraine. The BPPV can involve any of the three semi-circular canals. Most often, posterior semi-circular canal is involved, followed by lateral semi-circular canal and rarely the superior semi-circular canal. The pathology of BPPV is attributed to the sequestrated otoconia moving into the cupula or the canal, called cupulolithiasis or the canalolithiasis. Psychogenic vertigo5 Balance disorders and psychological disorders are believed to be comorbid conditions and there is enough of published research work to support this. About 64% of vertigo patients had psychiatric symptoms, and 45% of vertigo patients had panic symptoms. Vertigo/ imbalance and psychiatric disorders coexist as a result of neurological links between vestibular and autonomic systems – neuroanatomic connections between the two systems have now been established. The uncertainty of the timing and severity of the attacks of vertigo, the loss of confidence that occurs due to imbalance, the frustration that occurs due to inefficiency of diagnosis/treatment leads to anxiety, helplessness, panic disorders, agoraphobia, somatization, and depression psychopathology in patients. In between the attacks of vertigo there is quite often instability, lassitude, and a constant fear of recurrence of vertigo leading to a markedly severe negative effect on 26 the quality of life. Primary psychogenic vertigo can be suspected if vertigo is precipitated by social/psychological stimuli, or if the patient expresses extreme anxiety/fear (inappropriately more than clinical features), and if the patient complains of severe rotational vertigo but no clinical evidence of nystagmus, and other signs of actual vertigo/instability is found in the clinical tests and investigations. Psychogenic vertigo is caused by an independently diagnosable psychiatric problem such as anxiety, depression, somatization or malingering. Psychiatric-associated vertigo is the coexistence of an organic vertigo with an independently diagnosable psychiatric condition, such as anxiety, which might be comorbid or reactive. 27 Migraine-associated vertigo and basilar migraine The manifestations of migraine-associated vertigo are quite varied and may include episodic true vertigo, positional vertigo, constant imbalance, movement-associated disequilibrium, and/ or lightheadedness.6,7 Symptoms can occur before the onset of headache, during a headache, or most commonly, during a headachefree interval. As such, many patients who experience migraines have vertigo or dizziness as the main symptom rather than headache. For this reason, this article is devoted to the description of migraineassociated vertigo. 28 Basilar migraine, also known as Bickerstaff syndrome,8 is an important variant of migraine with aura. Bickerstaff syndrome consists of two or more symptoms (i.e., vertigo, tinnitus, decreased hearing, ataxia, dysarthria, visual symptoms in both hemifields of eyes, diplopia, bilateral paresthesias, or paresis, decreased level of consciousness) followed by a throbbing headache. Vascular ischemia The sudden onset of vertigo in a patient with additional neurologic symptoms (e.g., diplopia, dysarthria, dysphagia, ataxia, weakness) suggests the presence of vascular ischemia. Treatment of transient ischemic attack (TIA) and stroke includes preventing future events through blood pressure control, cholesterollevel lowering, smoking cessation, inhibition of platelet function (e.g., aspirin, clopidogrel, aspirin–dipyridamole) and possibly anticoagulation by warfarin. Acute vertigo caused by a cerebellar or brainstem stroke is treated with vestibular suppressant medication and minimal head movement for the first day. As soon as tolerated, medication should be tapered, and vestibular rehabilitation exercises should be initiated. Placement of vertebrobasilar stents may be considered in a patient with symptomatic critical vertebral artery stenosis that is refractory to medical management. Rarely, infarction or hemorrhage in the cerebellum or brainstem may present with acute vertigo as the only neurologic symptom. Given the risk of brainstem compression with a large cerebellar stroke, neurosurgical decompression may be indicated. 29 Lateral medullary syndrome The PICA syndrome is also known as “lateral medullary syndrome”, or “Wallenberg’s syndrome”, after Wallenberg’s description in 1895. This is the most common brainstem stroke. It is typified by vertigo, ipsilateral hemiataxia, dysarthria, ptosis, and miosis. Most patients with this stroke recover very well and often resume their previous activities.9 Patients often have a Horner’s syndrome (unilateral ptosis, miosis, and facial anhidrosis). Also there may be saccadic dysmetria (overshoot), and/or saccadic pulsion (pulling of the eye during vertical saccades toward the side of lesion). Prognosis is generally quite good with full or near-full recovery expected at 6 months. Diagnosis is generally via MRI. CT-angiography with 3D reconstruction has gotten good enough in recent years to be helpful too. Auditory brainstem response (ABR) testing is often abnormal in persons with central Horner’s syndrome10; however, as the lesion in Wallenberg syndrome is usually below the auditory connections, Horners due to Wallenbergs are not generally associated with abnormal ABR. The PICA syndrome may arise from the vertebral artery (the usual case), or as a separate branch of the basilar artery. Due to far more common origin from the vertebral artery, most PICA syndrome strokes actually are due to vertebral artery occlusion. Cardiac embolism causes only 5% of these strokes, while dissection causes 15%.11 PICA is the most common site of occlusion from propagating thrombus or embolism caused by injury to the third section of the vertebral artery, and Wallenberg’s syndrome is the most common stroke caused by chiropractic manipulation.12 30 Perilymph fistula A perilymph fistula (perilymphatic fistula [PLF], labyrinthine fistula) is a pathologic communication between the fluid-filled space of the inner ear and the air-filled space of the middle ear, most commonly occurring at either the round or oval window. The symptoms of PLF may include dizziness, vertigo, imbalance, nausea, and vomiting. However, patients usually report an unsteadiness, which increases with activity that is relieved by rest. Some people experience ringing or fullness in the ears, and many notice a hearing loss. Some people with fistulas find that their symptoms get worse with coughing, sneezing, or blowing their noses, as well as with exertion and activity. This sort of symptom goes under the general rubric of “valsalva-induced dizziness”, and it can also be associated with other medical conditions.13 Fistula 31 Acoustic neuromas Acoustic neuromas, also known as vestibular schwannomas, are non-malignant tumors of the 8th cranial nerve. Most commonly they arise from the covering cells (Schwann cells) of the inferior vestibular nerve. They can also arise within the labyrinth. Acoustics comprise about 6% of all intracranial tumors, about 30% of brainstem tumors, and about 85% of tumors in the region of the cerebellopontine angle – another 10% are meningiomas. Hearing loss is the most frequent symptom of acoustic neuroma. Tinnitus is very common in acoustic neuroma, which is usually unilateral and confined to the affected ear. Vertigo is more common with smaller tumors. Unsteadiness is much more prevalent than vertigo, and approximately 70% of patients with large tumors have this symptom. Acoustic neuroma Facial nerve Cochlea 32 Examination and investigations in vertigo patients A physical examination may reveal: • Eye movement (nystagmus) problems or involuntary eye movements • Lack of coordination and balance • Difficulty in walking • Hearing loss • Weakness of the limbs/trunk Spontaneous nystagmus Eyes open No nystagmus Nystagmus Eyes closed Eyes closed No nystagmus Nystagmus No nystagmus Peripheral disorder Central disorder Nystagmus Peripheral or central disorder 33 In all patients with vertigo or imbalance, there has to be at least a brief examination of the neurological system consisting of deep tendon reflexes, planter flexor/extensor, to look for any motor or sensory loss, the cerebellar tests, and of course a thorough examination of the balance system that consists of the vestibulospinal tests and the vestibulo-ocular tests. The vestibulospinal tests consist of the stepping test, the standing test that is the Romberg’s test, and the gait test. The vestibulo-ocular tests consist of tests for spontaneous nystagmus or any abnormal spontaneous eye movement like opsoclonus, ocular bobbing, etc., and some tests for provoked nystagmus include tests like the Dix–Hallpike test, test for gaze nystagmus, and the oculomotor tests. Sign/symptom Severity Associated symptoms Imbalance Positional Compensation Pre-morbid Spontaneous nystagmus • Nystagmus direction • Nystagmus fixation 34 Peripheral vertigo Severe with vomiting Mild Mild Often triggered Rapid, subsides in 48 h Hearing loss, ear infection Mixed Horizontal and torsional Suppression with fixation Central vertigo Moderate Severe Severe May be worsened Slow, persistent Hypertension, cardiovascular disease Pure nystagmus vectors Pure horizontal and pure vertical No suppression with fixation VOR – Head thrust test Smooth pursuit Direction of associated nystagmus Purely horizontal nystagmus Vertical or purely nystagmus Visual fixation Impaired Intact pursuit Uni-directional, fast phase opposite lesion* Always Never present Intact Broken pursuit Bi- or uni-directional May be vertical, torsional or horizontal May be present Inhibits No inhibition of the nystagmus nystagmus 14 Table 7: Peripheral vertigo vs central vertigo *In Ménière’s disease, the direction of fast phase is variable. Investigations • Caloric test without electronystagmography (ENG) or video nystagmography (VNG) recording is now obsolete and not advocated. • ENG/VNG should include all the oculomotor tests, test for spontaneous nystagmus, test for positional and positioning nystagmus, and of course the caloric tests. The rotational tests are helpful if available, but are not essential in each and every patient. While recording nystagmus by ENG or VNG, the eye movements in both horizontal as well as vertical directions should be recorded. Other tests that should also be done are the vestibular-evoked myogenic potentials (VEMP), posturography, craniocorpography, and 35 the basic audiological tests like pure tone audiometry, brainstemevoked response audiometry and electrocochleography as and when required. Imaging studies are not required in each and every patient of vertigo, but if the clinical tests or other investigations suggest possibility of some neoplastic, degenerative or vascular problem in the brain, then of course an imaging study specifically an MRI of the brain preferably with contrast is necessary. Pharmacotherapy5 Vertigo or imbalance is just a manifestation of some underlying disorder and not a disease in itself. Vertigo is just like fever in malaria or typhoid. The fever in such diseases is symptomatic and must be managed by treating the underlying cause by anti-malarial or antityphoid drugs. Similarly, for the management of vertigo, the clinician should first try to diagnose the cause of the vertigo or imbalance and then treat the underlying cause, and not merely try to suppress the symptoms. Prolonged symptomatic treatment of vertigo or imbalance by the so-called anti-vertigo drugs does more harm to the patient than good. It is similar to treating the fever in malaria or typhoid with paracetamol for months together. Unfortunately this is what is commonly practiced, which is not only unjust and unethical but also deplorable and condemnable. The symptom-relieving vestibular sedatives or anti-vertigo drugs like prochlorperazine, meclizine, dimenhydrinate, cinnarizine or betahistine are best when used for a very short duration of 3–7 days only, and should be discontinued as soon as the acute symptoms of vertigo subside. If a proper history is taken and clinical tests and investigations are properly performed, the underlying cause of the vertigo/instability can be treated ethically 36 and logically. There are specific treatment protocols for all the causes of vertigo: Ménière’s disease, vestibular neuritis, labyrinthitis, BPPV, PLF, migraine-related vertigo, psychogenic vertigo, cerebellar stroke, etc. Vertigo suppression drugs Drugs modifying underlying pathology Vestibular suppressants Cerebro-active drugs Anti-cholinergics Vasodilators Anti-histamines Diuretics Benzodiazepines Corticosteroids Calcium-channel antagonists Anti-bacterial drugs Anti-emetics 37 Treatment Treatment of vertigo can be divided into three main categories: specific, symptomatic, and rehabilitative. • Specific treatment for Ménière’s syndrome involves restriction of salt intake (1–2 g daily), diuretics (hydrochlorothiazide, acetazolamide), and rarely surgery for intractable cases. Vertebrobasilar insufficiency can be treated with anti-platelet drugs (aspirin 75–330 mg daily or ticlopidine 500 mg daily) and with anti-coagulants if the symptoms are severe and progressive. Migraine-related vertigo is treated by propranolol, imipramine and drugs like flunarizine or divalproic sodium. The specific treatment protocols for a few of the common causes of vertigo have been enumerated above. • Symptomatic therapy is used to control the troublesome symptoms of vertigo, nausea, and vomiting, whatever the cause. Commonly used vestibular suppressants include prochlorperazine meclizine, dimenhydrinate, promethazine, betahistine, cinnarizine, and diazepam. When nausea and vomiting persist, an anti-emetic drug such as domperidone or ondansetron can be combined with the vestibular suppressant drug. Though prochlorperazine is labeled as antiemetic drugs in pharmacology textbooks, it has very good antivertigo effect and is primarily used to control symptoms of acute vertigo. Of all the drugs available for symptomatic relief, the most effective is prochlorperazine. It not only manages vertigo but also the accompanying nausea and vomiting owing to the anti-muscarinic 38 (controls the vertigo) as well as anti-dopaminergic (controls the nausea and vomiting) properties associated with the drug. In case of acute vertigo, the dose regime commonly followed for prochlorperazine is 1 tablet (5 mg) thrice daily for 3–5 days. In chronic vertigo management, betahistine has been the trusted therapy since 1968. Betahistine is a histamine analog with an agonistic action. It is a H1 receptor agonist and antagonizes the H3 receptors. It increases cochlear and cerebral blood flow and regulates firing activity of the vestibular nuclei. Betahistine dose is advised as 24–48 mg/day. The biggest advantage of betahistine is that it is the only non-sedating anti-vertigo drug. All the other anti-vertigo drugs have some sedative effect, and therefore depress the central nervous system, which is detrimental to the central vestibular compensatory mechanism. This central vestibular compensatory mechanism is a faculty of the brain that restores normal balance function after a vestibular assault (vestibular labyrinth has been damaged). This is a natural mechanism which normalizes the patient’s balance system after it has been damaged by disease. Betahistine being a non-anti-histaminic and a non-sedative anti-vertigo drug can be used for somewhat longer periods unlike the anti-histaminic anti-vertigo drugs like prochlorperazine, cinnarizine, meclizine, and dimenhydrinate. • Vestibular rehabilitation helps the patient compensate for permanent vestibular damage.8 Vestibular exercise should begin as soon as the acute stage of nausea and vomiting has ended, and when the underlying disease process is subsiding. Many of the exercises result in dizziness. This sensation is a necessary stimulus for compensation; vestibular suppressants should be avoided during this period to ensure the maximum beneficial effect. Different types of exercises are available, the most popular 39 one being the age-old Cawthrone–Cooksey exercises. However, much better options are available now and some of the Yogic asanas and Tichi exercises have been found to be very effective in enhancing and expediting the vestibular compensatory mechanism. Vestibular Rehabilitation15–17 • Adaptation – A phenomenon which helps a patient with persisting peripheral dysfunctional state to regain normal balance. • Habituation – Repeated exposure of the body to “mismatched” sensory input. • Compensation – A goal-directed process induced by some recognized errors, directed towards its elimination. Exercise in bed: Eye movements Looking up and then down 40 Looking alternately left and right Convergence exercises Bending alternately forward and backward Turning alternatively to the left and then right Exercise in sitting position Bending forward and picking up objects from the floor Turning head and trunk alternately to the left and then right 41 Exercise in standing position 42 Changing from sitting to standing, initially with eyes open and then with the eyes closed Throwing a ping pong ball in an arc from hand to hand and following it with the eyes Throwing a small ball from hand to hand under the knee Throwing and catching the ball while walking Walking around in the room with eyes open and closed Walking up and down a flight of stairs Patient Questionnaire 1. Do you feel unsteady? 2. Do you feel as if the room is spinning around you? 3. Do you feel as if you are moving when you know you are sitting or standing still? 4. Do you lose balance and fall? 5. Do you feel as if you are falling? 6. Do you feel “lightheaded” or as if you might faint? 7. Do you have blurred vision? 8. Do you ever feel disoriented, such as losing your sense of time or where you are? 43 Patient fill-up form How can I help my doctor make a diagnosis? You can help your doctor make a diagnosis and determine a treatment plan by answering the questions below. Be prepared to discuss this information during your appointment. 1.The best way I can describe my dizziness or balance problem is: 2. How often do I feel dizzy or have trouble keeping my balance? 3. Have I ever fallen? If yes, A. When did I fall? 44 B. Where did I fall? C. Under what conditions did I fall? D. How often have I fallen? 4. The medicines I take: (Include prescription medications and over-the-counter medicines, such as aspirin, antihistamines, or sleep aids.) A. Name of medicine: B. How much (mg) and how often (times) per day: C. The condition I took this medicine is for: At your appointment, take a minute to write down any instructions your doctor has given you. Be sure to ask any questions you have before you leave the clinic/hospital. 45 References 1. Sturnieks DL, St. George R, Lord SR. Balance disorders in the elderly. Neurophysiol Clin. 2008;38(6):467–478. 2. Post RE, Dickerson LM. Dizziness: a diagnostic approach. Am Fam Physician. 2010;82(4):361–369. 3. Baloh RW. Vertigo. Lancet. 1998;352(9143):1841–1846. 4. Bauer CA, Jenkins HA. Otologic symptoms and syndromes. In: Flint PW, Haughey BH, Lund VJ, et al. editors. Cummings Otolaryngology: Head & Neck Surgery. 5th edition. Philadelphia, PA: Mosby Elsevier; 2010. Chapter 126. 5. Hain TC, Uddin M. Pharmacological treatment of vertigo. CNS Drugs. 2003;17(2):85–100. 6. Harker LA. Migraine-associated vertigo. In: Baloh RW, editor. Disorders of the Vestibular System. Oxford, England: Oxford University Press Inc.; 1996: pp. 407–417. 7. Buchholz DW, Reich SG. The menagerie of migraine. Semin Neurol. 1996;16(1):83–93. 8. Bickerstaff ER. Basilar artery migraine. Lancet. 1961;1:15. 9. Nelles G, Contois KA, Valente SL, et al. Recovery following lateral medullary infarction. Neurology. 1998;50:1418–1422. 10.Faught E, Oh SJ. Brainstem auditory responses in brainstem infarction. Stroke. 1985;16:701–705. 46 11.Kim JS. Pure lateral medullary infarction: clinical– radiological correlation of 130 acute, consecutive patients. Brain. 2003;126(Part 8):1864–-1872. 12. Caplan LR. Vertebrobasilar disease. In: Barnet HJM, et al. editors. Stroke: Pathophysiology, Diagnosis and Management. New York: Chrchill-Livingstone; 1986:549–619. 13. Swartz R, Longwell P. Treatment of vertigo. Am Fam Physician. 2005;71(6):1115–1122. 14. Daroff RB. Faintness syncope, dizziness and vertigo. In: Harrisons Principles of Internal Medicine. 14th edition, p. 105. 15.Kirtane MV. Role of adaptation exercises in clinical practice. Indian J Otolaryngol. 1999;51(2):27–36. 16.Biswas A. Clinical Audio-Vestibulometry for Otologista and Neurologists. 4th edition. Mumbai: Bhalani Medical Book House; 2010. 17. Biswas A. An Introduction to Neurotology. 2nd edition. Mumbai: Bhalani Medical Book House; 2005. 47 Notes 48 Notes 49 Notes 50 For the use of a Registered Medical Practitioner, Hospital or Laboratory only xxxxxxxxxx Abbott India Limited 3-4, Corporate Park, Sion-Trombay Road, Mumbai - 400 071 Visit us at: www.abbott.com * Trademark of the Abbott Group of Companies Copyright 2011 abbott. All rights received. Conceptualized, Edited & Designed by Further information available on request from: