Ent Trends, Vol2, Issue 2, April 2011

ENT

ORTHO

NEUROLOGISTNEURO

SURGEON

MEDICINE

BALANCE– ANATOMY & PHYSIOLOGY

APPROACH TO A PATIENT

WITH VERTIGO

BENIGN PAROXYSMAL POSITIONAL VERTIGO

MENIERE’S DISEASE

QUIZ

ISSUE 2 APRIL 2011 VOLUME 2

ENT E– NEWSLETTER ON RECENT TRENDS IN ENT

VERTIGO Issue 2

� BALANCE– ANATOMY

� APPROACH TO A PATIENT WITH VERTIGO

� QUIZ

© Dr. Pooja Kataria, New Delhi, April 2011

trends

Volume 2 Issue 2 April 2011 Pg2

Hello readers,

Welcome to the second issue of Volume 2 of our e newsletter.

Often, an ENT practitioner is just one of the several specialists a patient

suffering from vertigo consults. Due to the significant overlap amongst the

causes of vertigo in various specialties, the patients are mostly given symp-

tomatic treatment. In doing that, we forget that it is more important to

treat the patient than the symptoms. A patient with vertigo/dizziness may

not be suffering from a grave pathology but is usually symptomatically very

distressed. To diagnose the cause requires expertise along with a battery

of tests.

We will cover the same in this issue including a brief on two important

otological causes of vertigo– Meniere’s Disease and Benign Paroxysmal Posi-

tional Vertigo.

Lets hope, readers benefit from this issue of our newsletter and, get tips

to approach a patient presenting with vertigo/dizziness.

Happy reading to all of you.

Regards,

ENT TRENDSENT TRENDSENT TRENDSENT TRENDS

ISSUE 2 VOLUME 2 APRIL 2011ISSUE 2 VOLUME 2 APRIL 2011ISSUE 2 VOLUME 2 APRIL 2011ISSUE 2 VOLUME 2 APRIL 2011

EEEE–––– NEWSLETTER ON RECENT TRENDS NEWSLETTER ON RECENT TRENDS NEWSLETTER ON RECENT TRENDS NEWSLETTER ON RECENT TRENDS

Advisor

Dr. A.K. Agarwal

Editorial Board

Pooja Kataria Sumit Mrig Ankush Sayal

Volume 2 Issue 2 April 2011 Pg3

ANATOMY AND PHYSIOLOGY OF BALANCEANATOMY AND PHYSIOLOGY OF BALANCEANATOMY AND PHYSIOLOGY OF BALANCEANATOMY AND PHYSIOLOGY OF BALANCE

The INTERNAL EAR is not only the essential part of the organ of hearing, but also of balance. It is called the labyrinth, from the complexity of its shape, and consists of two parts: the OSSEOUS LABYRINTH, a series of cavities within the petrous part of the temporal bone, and the MEMBRANOUS LABYRINTH, a series of communicating membranous sacs and ducts, con-tained within the bony cavities. OSSEOUS LABYRINTH —The osseous labyrinth consists of three parts: the vestibule, semicircular canals, and cochlea.

THE SEMICIRCULAR CANALS: 3 in number- superior, horizontal and posterior. They contain the semicircular ducts. They open into the vestibule through 5 openings. The anterior ends have a dilated portion called the ampulla which opens independ-ently into the vestibule. The posterior ends, which are not dilated, of the superior and posterior SCC fuse together and then open into the vestibule whereas the posterior end of the lateral SCC opens independently. The lateral canal of one ear is very nearly in the same plane as that of the other; while the superior canal of one ear is nearly parallel to the posterior canal of the other.

MEMBRANOUS LABYRINTH :- The membranous labyrinth consists of the cochlear duct, the semicircular canals, the endolymphatic sac and duct. The membranous labyrinth is lodged within the bony cavities just described, and has the same general form as these; it is, how-ever, considerably smaller, and is partly separated from the bony walls by a quantity of fluid, the perilymph. In certain places it is fixed to the walls of the cavity. The membranous labyrinth contains fluid, the endolymph, and on its walls the ramifications of the acoustic nerve are distributed. Within the osseous vestibule the membranous labyrinth does not quite preserve the form of the bony cavity, but consists of two membranous sacs, the utricle, and the saccule. The utricle receives the openings of the 5 Semicircular canals. It is concerned with linear acceleration. The saccule also is con-cerned with linear acceleration. Both have sensory epithelium which is called Macula. The semicircular ducts correspond to the semicircular canals. They are concerned with angular acceleration and deceleration. The cochlear duct lies between the scala tympani and scala vestibule, also known as the scala media.

Volume 2 Issue 2 April 2011 Pg 4

PHYSIOLOGY

The functions of the vestibular system are to sense angular acceleration, linear acceleration and to coordinate head and eye move-ments as well as maintain the antigravity and lower body muscles in relation to the head. The semicircular canals provide sensa-tion for angular acceleration. The membranous labyrinth moves with head motion while the endolymph does not, causing a rela-tive flow of endolymph and deflection of the cupula. Each hair cell has a resting potential and its associated neuron has a sponta-neous discharge. Movement will cause an increase in the discharge rate on one side and a decrease from the paired canal on the opposite side.

The otolith organs are sensitive to linear acceleration. Movement of the otoconia mass deflects the hair cells attached to it. The maculae have hair cells oriented in many directions so linear acceleration in any direction may be sensed. The saccule is most sen-sitive to gravity since it is in the vertical plane.

The reflexes involving the vestibular system include the vestibulo-ocular reflex and the vestibulospinal reflex. The vestibule-ocular reflex helps maintain fixation of the eyes on an object with movement of the head. Both angular and linear acceleration sig-nals are use in the vestibule-ocular reflex. Projections from the vestibular nuclei to the extraocular muscle nuclei allow for eye movements that counteract head movements for gaze stabilization. The vestibulospinal reflex allows for input from the vestibular organs to be use for posture and stability in a gravity environment. The projections from the vestibular nuclei travel to antigravity muscles for coordinated movements to maintain posture.


Of all the human vestibular pathways, the VOR remains the most important and most studied. At its simplest level the VOR is required to maintain a stable retinal image with active head movement. When an active head movement is not ac-companied by an equal but opposite conjugate movement of the eyes, retinal slip occurs. When the VOR is affected bilaterally (as could occur from systemic aminoglycoside poisoning) patients characteristically complain of visual blurring with head mo-vement, better known as oscillopsia, in addition to having significant complaints of imbalance and ataxia.

Figure 1 and 2 depicts the various supranuclear oculomotor centres involved in maintainance of Vesticulo-ocular re-flex. The abbreviations have been detailed below along with the various functions these regions perform. Figure 1:

RiMLF = Rostral interstitial nucleus of the medial longitudinal Fascicle It is responsible for maintaining vertical saccades i.e velocity, accuracy and symmetry of vertical saccades. Lesions involving the riMLF would lead to internuclear opthalmoplegia and upbeat nystagmus. PPRL = Paramedian pontine reticular formation It is responsible for maintainance of horizontal saccades. Its palsy leads to ipsiverse horizontal parasis of saccades. INC = Interstitial nucleus of Cajal It is responsible for vertical gaze holding. Its dysfunction leads to vertical gaze evoked nystagmus. NPH = Nucleus prepositus hypoglossi It is responsible for horizontal gaze holding function. Its dysfunction leads to horizontal gaze evoked nystagmus. CP= Posterior commisure It is responsible for convergence retraction nystagmus


CEREBELLUM AND ITS CONTRIBUTION IN VOR: The cerebellum works like the brake of a car and maintains an inhibitory output through the purkinje cells via neurotransmitter GABA. Thus, it maintains the accuracy of saccades and loss of its function leads to hypermetric saccades and loss of smooth pursuit. Figure 2:

VERMIS: Responsible for dysmetric saccades FLOCULLUS: Most commonly involved in cerebellar lesions. It is responsible for : - smooth pursuit deficit, ♦ Impaired VOR suppression ♦ Gaze evoked nystagmus ♦ Down beat nystagmus ♦ Rebound nystagmus NODULUS: Responsible for

⇒ Central positioning nystagmus ⇒ Periodic alternating nystagmus

EXAMINATION OF A PATIENT WITH VERTIGO TO RULE OUT C ENTRAL CAUSE: Whenever a patient with vertigo and/or nystagmus presents in the clinic the following should be the basic 4 questions that need to be answered:

Is there a deficit? Is it peripheral/ central If it is central, is it in the brainstem/ cerebellum If it is in the brainstem, is it the midbrain, pons or medulla

It has been observed that the ratio of central to peripheral vertigo is greater than 50% and in more than 50% cases of central cause of vertigo, associated symptoms such as cerebellar signs are absent. The following are clinical tests that need to be performed in addition to the routine ENT examination to differentiate between central and peripheral vertigo.

COVER- UNCOVER TEST: This is to test malalignments of the visual axis. The prerequisite for all of these tests is foveal

fixation. The unilateral cover test reveals heterotropia (manifest strabismus), i.e. a malalignment of the visual axis when both eyes look at a single target. First the patient has to fixate either a near target (at a distance of 30 to 40 cm e.g. exam-iner’s nose) or one 5 to 6 mts away. Then the examiner covers one eye and looks for movements of the uncovered eye (correction movements). If the uncovered eye moves from the inside outward, esotropia is present; if it moves from the out-side inward, exotropia; if it moves from above downward, hypertropia; if it moves below upwards, hypotropia. The other eye is then examined.


The unilateral cover test reveals heterophoria (latent strabismus), i.e., a malalignment of the visual axis when an object is fixed by only one eye. At first one eye is covered, then the cover is removed and its corrective movement is observed. If the eye moves to the outside, esophoria is present; if it moves to the inside, exophoria; if it moves downward, hyperphoria; if it moves upwards, hypophoria. The alternate cover test reveals the maximum deviation of the eye axis, in cases of tropia and phoria. It is also useful for de-tecting skew deviation (part of the ocular tilt reaction). Vertical corrective movements are looked for, when the cover is switched from one eye to the other. In contrast to 4th cranial nerve palsy, the vertical alignment changes little during different directions of gaze. The cover tests are done to rule out latent or manifest strabismus from skew deviation in which no movements shall be visual-ized. Remember skew deviations (vertical divergence) are associated with central lesions such as wallenberg’s syndrome.

Figure 3. Cover- Uncover Test

Check for spontaneous nystagmus: Ask the patient to fix eye over an object 25- 30cm away and check nystagmus in the primary

position. This allows us to rule out horizontal, vertical (upbeat/downbeat) and torsional nystagmus. Remember nystagmus gets suppressed by fixation in peripheral vestibular dysfunction and remains stationary or increases in central vestibular dysfunc-tion; a congenital nystagmus beats as a rule, horizontally at various frequencies and amplitudes and increases during fixation

After checking for possible eye movements in primary position and the misalignment of the axis of the eyes (cover test), the exam-iner should then establish the range of eye movements monocularly and binocularly in the nine end positions; deficits found here can indicate, e.g., ocular muscle or nerve palsy. Gaze holding deficits can also be determined by examining eccentric gaze position.

When the eye is taken to the end positions, look for ability of gaze holding and any gaze evoked nystagmus. Horizontal gaze

evoked nystagmus can indicate a structural lesion in the area of brainstem or cerebellum (flocculus, NPH, Vestibular nucleus). Vertical gaze evoked nystagmus is observed in lesions of the INC. Most important cause of gaze evoked nystagmus in all di-rections is medications (e.g., phenytoin, tegretal) and alcohol intoxication. Remember that down beat nystagmus is most prominent in the lateral gaze.

Look for any deficits in convergence reaction i.e., when an object is moved from a distance of 50cm towards the patients eye, this

causes vergence, accommodation and miosis. The neurons important for this lie in the mesencephalic reticular formation and oculomotor nucleus. Lesions of rostral midbrain lesions and tumors of pineal region and thalamus lead to abnormal conver-gence reaction. Convergence retraction nystagmus is seen with lesions of posterior commissure.

The above mentioned clinical examination for spontaneous nystagmus, range of eye movements, gaze evoked nystagmus can be

performed using frenzel’s glasses. These 20 diopters glasses prevent visual fixation. Remember spontaneous nystagmus indi-cates a tone imbalance of the vestibule-ocular reflex; if it is caused by a peripheral lesion e.g. vestibular neuritis, the nystagmus is typically damped by visual fixation.Head shaking nystagmus shows a latent asymmetry of the so called velocity storage, which can be due to peripheral and central vestibular disorders.


Author details: Dr. Tripti Brar, Senior Resident, Department of ENT & Head and Neck surgery, Maulana Azad Medical College, Lok Nayak Hospital & Associated Hospitals. Dr. Ankush Sayal, Senior Resident, Department of ENT & Head and Neck surgery, Maulana Azad Medi-cal College, Lok Nayak Hospital & Associated Hospitals.

Clinical examination of saccades: Ask the patient to glance back and forth between two horizontal and two vertical targets. The velocity, accuracy and the conjugacy of the saccades should be noted. Normal individuals can immediately reach the target with a fast single movement or one small corrective saccade. Slowing of saccades—often accompanied by hypometric saccades--- occurs for example with intoxication (medication, especially antiepileptics or benzodiazepines) or in neurodegenerative disorders. Slowing of horizontal saccades is ob-served in brainstem lesions; there is most often dysfunction of the ipsilateral PPRF. Slowing of vertical saccades indicates a midbrain lesion in which the rostral intermedial MLF (riMLF) is involved, not only in ischemic inflammatory diseases but also in neurodegen-erative diseases, especially progressive supranuclear palsy. Hypermetric saccades, which can be identified by a corrective saccade back to the object, indicate lesions of the cerebellum (especially the vermis) or the cerebellar pathways.

Clinical examination of the smooth pursuit eye movements: The patient is asked to tract visually any object moving slowly in horizontal and vertical directions while keeping the head stationary.

Corrective (catch-up or back up) saccades are looked for; they indicate a smooth pursuit gain that is too low or too high. Many anatomical structures ( visual cortex, frontal eye fields, cerebellum, vestibular and ocular motor nuclei) are involved in smooth pursuit movements, which keep the image of the object on the fovea. Remember that even healthy persons exhibit a slight smooth pursuit during downward gaze. For this reasons a saccadic smooth pursuit as a rule does not allow either an exact topog-raphical or etiological classification. Marked asymmetries of smooth pursuit, however, indicate a structural lesion; strongly im-paired smooth pursuit is observed in intoxication (antiepileptics, benzodiazepines or alcohol) as well as degenerative disorders involving the cerebellum or extrapyramidal system. A reversal of smooth pursuit is typical for congenital nystagmus.

HALMAGYYI’S HEAD-IMPULSE TEST: It tests the horizontal vestibule-ocular reflex. In this the examiner holds the patient’s head between both hands, asks him to fixate

a target in front of his eyes, and rapidly turns the patient’s head horizontally to the left and then to the right. This rotation of the head in a healthy subject causes rapid compensatory eye movements in the opposite directions. In cases of unilateral labyrinthine loss, during rapid head rotations towards the affected ear, the patient is not able to generate a fast contraversive eye movement and has to perform a corrective (catch up) saccade to fixate the target.

VISUAL FIXATION SUPPRESSION OF THE VESTIBULO-OCULAR REFLEX (VOR) Before performing this test the examiner must be sure that the VOR is intact. The patient is asked to fixate a target in front of his

eyes while moving his head uniformly, first horizontally and then vertically. The examiner should watch for corrective sac-cades. A disorder of visual fixation suppression of the VOR is often observed in lesions of the cerebellum.

In summary, 4 basic tests that have been found to be helpful in differentiating central from peripheral vertigo include:

Gaze evoked nystagmus Skew deviation Head impulse test Saccadic smooth pursuit

Remember that any patient presenting with acute onset nystagmus with normal head impulse test is most likely due to central lesion.


DIZZINESS

SINGLE

EPISODE

RECURRENT

ATTACKS

COUNTINOUS

IMBALANCE

1.

COCHLEAR

SYMP-

TOMS

NO

COCHLEAR

SYMP-

TOMS

COCHLEAR

SYMP-

TOMS

NO CO-

CHLEAR

SYMP-

TOMS

4.

NO ASSOC

SYMP-

TOMS

5.

ASSOC.

SYMP-

TOMS

6.

NO ASSOC

SYMP-

TOMS

7.

ASSOC

SYMP-

TOMS

NO CO-

CHLEAR

SYMP-

TOMS

8.

NO ASSOC

SYMP-

TOMS

9.

ASSOC

SYMP-

TOMS

2.

NO ASSOC

SYMP-

TOMS

3.

ASSOC

SYMP-

TOMS

APPROACH TO A PATIENT WITH VERTIGO


CAUSES 1.

Vascular Labyrinthine lesion Labyrinthine fistula Viral labrinthitis

2. Inner ear lesion Vestibular neuronitis

3. Vascular brain stem lesion

4. Endolymphatic hydrops Infection– CSOM, syphilis CP angle lesion

5. CP angle lesion

6. BPPV

7. Neurological Temporal lobe lesion Epilepsy Multiple sclerosis Migraine Cervical vertigo General medical -hypoglycemia.hyperventilation CVS causes

8. CVS – postural hypotension CNS – cerebellar lesions, ms

9. Vestibulotoxic drugs.

ENT

ORTHO

NEUROLOGISTNEURO

SURGEON

MEDICINE


VERTIGO—

Patients of vertigo are generally first seen by a general practioner and are referred from one speciality to other without making any diagnosi s.

Vertigo A sense of feeling the environment moving when it d oes not. Persists in all positions. Aggravated by head movement. Dysequilibrium A feeling of unsteadiness or insecurity without rot ation. Standing and walking are difficult. Giddiness Swimming, floating, giddy or swaying sensation in t he head or in the room. Unsteadiness Sense of imbalance


Any mismatch between the afferent & the efferent c auses vertigo. Pathophysiology

Balance requires – Normal functioning vestibular system Input from visual system (vestibulo-ocular) Input from proprioceptive system (vestibulo-spinal)

Disruption of balance between inputs results in : vertigo (acute) disequilibrium (chronic)

Afferent

VisualProprioceptiveVestibular

CNSEfferent

OculomotorSceletal musclesVegetative

Dizziness

DISORDERS OF BALANCE Differential diagnosis

• Benign Paroxysmal Positional Vertigo • Meniere’s Disease • Vestibular Neuronitis • Autoimmune Inner Ear Disease • Trauma • Toxic Substances/Medications • Migraine • Acoustic Neuroma • Vascular Disorders • Multiple Sclerosis • Cervical Vertigo History: what to cover;

Onset of symptoms Chronologically Periods of complete freedom Speed of both onset and resolution Ensure on same wavelength

Predominantly one can distinguish vertigo as of per ipheral or central origin. A brief classification according to the duration & site of origin is as below :


Time Peripheral Central

Seconds BPPV VB-TIA, aura of epilepsy

Minutes perilymph fistula VB-TIA, aura of migraine

(Half) hours Meniére disease basilar migraine

Days vestibular neuronitis labyrinthitis

VB stroke

Weeks, Month acoustic neuroma, drug toxicity

multiple sclerosis cerebellar

degenerations

Examination ♦ Ears

♦ Hearing

♦ Nystagmus

♦ Balance

♦ BP

♦ Positional testing

♦ Neurological examination

Protocol for evaluation of vertigo patient include s clinical examination and battery of tests :


Investigations (i) Hearing Tests a. P.T.A. b. Impedence Audio c. EcHog (ii) Vestibular Function Test a. Bi-thermal caloric test. b. Dix-Hallpike Manouvere c. Unter Berger test. d. ENG e. Video-oculography f. Dynamic posturography (iii) Haematology a. FBC + ESR b. VDRL/TPHA (iv) Radiology a. Mastoid X-rays b. Internal auditory meatus X-rays c.CTscan/MR scan Apart from routine examination of the ear few bed s ide clinical tests helps in reaching to a diagnosis of vertigo HEAD SHAKE TEST Head-shaking nystagmus (HSN) is a jerk nystagmus that may follow a prolonged sinusoidal head oscillation. It is not new -- it was first described in 1907 by Robert Bárány (1907). Moritz called it "kopfschutteinnystagmus" (1951). Subse-quent studies (Borries 1923; Klestadt 1936; Vogel 1929) described different techniques of eliciting the nystagmus and advanced hypotheses regarding its pathophysiology (Fetter et al. 1990; Hain and Spindler 1993; Halmagyi and Curthoys 1988; Katsarkas et al. 2000; Minagar et al. 2001; Perez et al. 2004) It is most commonly elicited in the following way: The patient is positioned upright and instrumented so that fixation is removed but horizontal and vertical eye movements can be observed. The test is best performed using video Frenzel goggles. The test cannot be done without a method of eliminating fixation. Eye movements are observed in darkness for 10 seconds to obtain a baseline. Next, the examiner grasps the patient’s head and moves it briskly back and forth in the yaw plane (around the vertical axis) , aiming for a frequency of about 2 Hz and a displacement of the head of approximately 30 degrees to either side. Ideally, the head should be pitched about 20 degrees downward with respect to vertical so that the axis of rotation is close to being parallel to the axes of the lat-eral canals, but practically the results of the test are not sensitive to this procedure. The head-shaking is continued for 20 cycles and then abruptly stopped. In normal subjects or persons with symmetrical vestibular loss (such as bilateral vestibular loss), no nystagmus is ex-pected. In persons with a dynamic imbalance between the ears (such as due to unilateral vestibular neuritis or an acoustic neuroma), a nystagmus is often seen (usually beating towards the “better” ear (Hain et al. 1987; Katsarkas et al. 2000)) which decays over about 30 seconds. This is referred to as the first phase of nystagmus, because in some cases it is followed by a second phase of nystagmus that is weaker, decays more slowly, and is directed towards the “bad” ear. The main value of seeing a secondary phase is that one can clearly identify the primary phase (sometimes the primary nystagmus is very short). Rarely, horizontal head-shaking produces a non-horizontal nystagmus, such as vertical nystag-mus (Wu et al. 2005) or torsional nystagmus (Califano et al. 2001). This is called a “perverted” head-shaking nystagmus.


VIBRATORY TEST FOR VESTIBULAR DISORDERS

A vibratory stimulus has been applied not only to the mastoids but also to the vertex and neck 1,2. In 1999, Hamann and

Schuster 3 found that the sensitivity of the test was increased using a frequency of 60 Hz instead of 100 Hz. In 2004, Du-

mas et al. 7reported complete concordance between MVT, the head shaking test (HST) and the caloric test for detecting

the side with total vestibular loss. It was also suggested that MVT elicits vibratory nystagmus (VN) in healthy subjects 2 5.

It is not clear how mastoid vibration causes nystagmus in patients with peripheral vestibular deficit. Vibration has been

shown to excite semicircular canals and otolithic afferents in various animal species6-8 and in humans 1 3 9,10, indicating

that the effects on eye movement can be attributed to direct stimulation of intact vestibular receptors. Kalberg et al., in

particular, showed that vibration to the mastoid bone induces eye movements similar to those seen acutely, without vi-

bration, after unilateral vestibular loss and that the eye rotation axis of vibration-induced nystagmus is related to the ex-

tent of the unilateral vestibular deficit 9. The vibratory test, according to some authors, is not unlike the simultaneous ca-

loric test 4. Vibration also seems to increase afferent activity from stimulated muscles 11, suggesting that the effects may

be due to interaction between neck proprioceptors and the vestibular system 12,13

The aim of the present study was to determine the sensitivity and specificity of MVT in patients with damage caused by

vestibular neuritis, comparing results with those of the caloric test, the current gold standard for identifying unilateral defi-

cit in vestibular function. MVT was also compared with the head shaking test (HST) and with the head thrust test (HTT),

other conventional bedside tests used in the detection of vestibular asymmetry. Apart from bed side clinical test which help in diagnosing cause of vertigo, balance regulation of the body can be evalu-ated with the help of CDP. It is generally classified into static & dynamic posturogaphy. Computerized Dynamic Posturography (CDP) Computerized dynamic posturography (CDP) is an established test of postural stability. While ENG and rotation testing assess visual-vestibular interactions, CDP provides information about motor control or balance function under varying environmental conditions. The ability to maintain balance depends not only on vision and the vestibular system, but also on information that the brain receives from the muscles and joints which provide clues such as the direction of head turn and the texture and slope of the walking surface. CDP tests the relationships among all balance system components--eyes, somatosensory system, and vestibular system . It measures the person's response to environments in which the amount of reliable information from the eyes and somatosensory system is varied.


The test involves standing on a platform, typically with some form of visual target to watch. The platform and/or the visual target move while pressure gauges under the platform record shifts in body weight (body sway) as the person being tested maintains balance. (A safety harness is worn to prevent falling during the test.) Posturography gives information about how well balance is maintained during challenging situations. It can help doctors plan other vestibular testing, as well as assist in treatment design. ROLE OF ENG It helps in documenting the type of nystagmus with effect of maneuvers on the nystagmus. The eyes are closely linked to the inner ear; these organs depend on each other for good balance and clear vision. Head movement or other stimulation of the inner ear sends signals to the muscles of the eyes via the nervous system; this is called thevestibulo-ocular reflex, or VOR. The VOR normally generates eye movements that maintain clear vision with head move-ment. Electronystagmography (ENG) is a battery (group) of eye-movement tests that look for signs of vestibular dys-function or neurological problems by measuring nystagmus (a type of involuntary eye movements). ENG tests are the most common ones administered to people with dizziness, vertigo, and/or balance disorders, although the test battery and some testing methods vary widely. During ENG, eye movements are recorded and analyzed via small electrodes placed on the skin around the eyes. The electrodes attach to the skin with an adhesive, much like a small bandage. Alternatively, eye movements may be re-corded by videonystagmography (VNG) using an infrared video camera mounted inside goggles that the patient wears instead of sticky-patch electrodes. One ENG test evaluates the movement of the eyes as they follow a moving target. Another observes eye movements as the head is positioned in different directions. During the caloric test warm or cold water or air is circulated in the ear canal. The temperature change stimulates the inner ear in order to test the nystagmus response. Caloric testing – cold and warm water irrigation

MEDICAL TREATMENT FOR VERTIGO PRINCIPLES OF TREATMENT:

Medical treatment is advisable only in acute cases of vertigo with emphasis on rehabilitation exercises once the acute crises is over.

Lot of vestibular suppressants are available in the market , but caution – not to add two or more vestibular suppres-sants together as they not only make the patient more dizzy but also delay brain compensation.

Diazepam is the best vestibular suppressant & is used when other drugs fail to control vertigo. Stemetil should not be given for more than a wk as it delays brain compensation.

A brief description of the various antivertigo drug s is given below:



BIBLIOGRAPHY

1 Dumas G, Michel J. Valeur semiologique du test de vibration osseux cranien. Liege: Compte rendu des seances de la Societé

d’Otoneurologie de langue française, XXXIe symposium, Liege 1997, Edition IPSEN.

2. Michel J, Dumas G, Lavielle JP, Characon R. Diagnostic value of vibration-induced nystagmus obtained by combined vibratory

stimulation applied to the neck muscles and skull of 300 vertiginous patients. Rev Laryngol Otol Rhinol 2001;2:89-94.

3. Hamann KF, Schuster EM. Vibration induced nystagmus – a sign of unilateral vestibular deficit. J Otorhinolaryngol Relat Spec

1999;61:74-9.

4. Dumas G, Lavielle JP, Schrmerber S. Vibratory test and head shaking test and caloric test: a series of 87 patients. Ann Otolaryngol

Chir Cervicofac 2004;121:22-32.

5. Perez N. Vibration induced nystagmus in normal subjects and in patients with dizziness. A videonystagmography study. Rev

Laryngol Otol Rhinol 2003;2:85-90.

6. Young ED, Fernandez C. Responses of squirrel monkey vestibular neurons to audio frequency sound and head vibration. Acta

Otolaryngol 1977;84:352-60.

7. Christensen-Dalsgaard J, Narins PM. Sound and vibration sensivity of VIIIth nerve fibres in frogs Leptodactylus abilabris and

Rana pipiens pipiens. J Comp Physiol A 1993;172:653-62.

8. Wit HP, Bleeker JD, Mulder HH. Responses of pigeons vestibular nerve fibers to sound and vibration with audiofrequencies. J

Acoust Soc Am 1984;75:202-8.

9. Karlberg M, Aw S, Black R, Todd M, MacDougall H, Halamgyi M. Vibration-induced ocular torsion and nystagmus after unilat-

eral vestibular deafferentation. Brain 2003;126,956-64.

10 Lackner JR. Elicitation of vestibular side effects by regional vibration of head. Aerospace Med 1974;45:1267-72.

11. Roll JP, Vedel JP. Alteration of proprioceptive messages induced by tendon vibration in man: a microneurographic study. Exp

Brain Res 1989;76:213-22.

12. Strupp M, Arbusow V, Dieterich M, Brandt T. Perceptual and oculomotor effects of neck muscle vibration in vestibular neuritis:

ipsilateral somatosensory substitution of vestibular function. Brain 1998;121:677-85.

13. Popov KE, Lehkel H. Visual and oculomotor responses induced by neck vibration in normal subjects and labyrinthine-defective

patients. Exp Barin Res 1999;128:343-52.

Author details: Dr. Sumit Mrig. Senior Consultant, Department of ENT & Cochlear Im palnt Surgery, Primus Super-speciality Hospital, New Delhi.


BENIGN PAROXYSMAL POSITIONAL VERTIGOBENIGN PAROXYSMAL POSITIONAL VERTIGOBENIGN PAROXYSMAL POSITIONAL VERTIGOBENIGN PAROXYSMAL POSITIONAL VERTIGO

First described by Barany in 1921, the entity of benign paroxysmal positional vertigo (BPPV) was more fully defined in 1952 by Dix and Hallpike, who originated the provocative test now referred to as the “ Hallpike maneuver”. BPPV can appear at any time from childhood to senility, but at least the idiopathic form is typically a disease of old age. Male to female ratio is 1:1. Although the most common cause is head trauma but BPPV also occurs after excessive bed rest in connection with other illnesses or after operation. About 10% of the spontaneous cases and 20% of the trauma cases show bilateral BPPV. It is called benign because it resolves spontaneously within weeks to months, in some cases, however it can last for years. PATHOPHYSIOLOGY According to the histologically based cupulolithiasis model of Schuknecht (1969), heavy, anorganic particles (Otoconia) of specific weight, which become detached as a result of trauma or spontaneous degeneration from the utricular otoliths of the cupula, settle in the underlying ampulla of the posterior canal. Whereas the cupula normally has the same specific weight as the endolymph, it is heavier with these particles (heavy cupula), i.e., the canal is transformed from a sensor of rotatory acceleration into a transducer of linear or angular acceleration. Despite its widespread acceptance, this theory failed to explain many of the typical criteria of nystagmus in cases of positional vertigo. Various studies have shown that when a heavy cupula is created by alcohol or deuterium ingestion, the resulting nystagmus, in a particular head position, is sustained for a longer period of time, rather than transient as in the classical nystagmus. Based on the observation by Pames And McClure, Epley, in 1992, proposed the canalolithiasis hypothesis which could explain all symptoms of positioning nystagmus. According to this hypothesis, otoconia or canaliths float freely within the endolymph of the semicircular canal instead of being firmly attached to the cupula and the heavy conglomerate, which almost fills the canal, is assumed to be the cause of the positioning vertigo. The movement of the conglomerate causes either an ampullofugal or ampullopetal deflection of the endolymph depending on the direction of the sedimentation. CLINICAL PRESENTATION The main symptoms of BPPV include severe attacks of rotatory vertigo with or without nausea, which are caused by rapid changes in head position relative to gravity. Typical triggers include lying down or sitting up in bed, turning around in bed and also bending over to tie shoe laces or extending the head in order to look up or do something above the head. They frequently occur in the morning and are most pronounced during the first change in position after sleep; re-peated changes in position cause a transient lessening of the attacks. BPPV is elicited by extending the head or positioning the head or body toward the effected ear. Rotatory vertigo and nys-tagmus occur after such positioning with a short latency of seconds in form of a crescendo/decrescendo course of maxi-mally 30-60 seconds. The beating direction of nystagmus depends on the direction of gaze; it is rotatory when the gaze is to the undermost ear and mostly vertical (to the forhead) during gaze to the uppermost ear. The nystagmus corre-sponds to the ampullofugal excitation of the posterior canal of the undermost ear. TREATMENT 1. PHYSICAL LIBERATORY MANEUVERS: When correctly performed, all three physical liberatory maneuvers (Simont or Epley liberatory maneuvers, Brandt-Daroff exercises) are successful in almost all patients (Figure 1, 2 and 3 respectively). Simont’s maneuver is quickly performed in three steps with the aid of a therapist as the patient lies on the examination couch. It is important that the head of the sitting patient is turned by 45 degrees to the healthy ear, in order to put the re-sponsible canal into a position parallel to the movement during the positioning. Relief is thus achieved in about 50% of the cases with one single maneuver. Epley’s liberatory maneuver requires that the patient’s head and trunk be rotated after being tilted backward into slightly head-holding position.


If, however, the plug is not dislodged during the outpatient visit the patient can be quickly instructed to perform Brandt-Daroff exercises at home. These exercises should be repeated 5 times a day. They are most effective when performed after a period of rest, for example, in the morning and at noon as the clot that develops during sleep can be easily removed from the canal than single otoconia. Despite successful liberatory maneuvers, many patients com-plain of transient attacks of postural vertigo and dizziness. This can be explained by the partial repositioning of the otoconia toward the otolith organs.

Fig 1. Schematic drawing of the Simont’s maneuver of a patient with right BPPV. (1) In the sitting position, the head is turned horizontally 45 degree to the unaffected ear. (2) The patient is made to lie down on the side of affected ear first with the nose pointing upwards. The patient maintains this position for 3 minutes. (3) The Patient is made to lie down on the side of unaffected ear with nose pointing downwards and maintain this for 3 minutes, causing the clot to exit the canal. The patient is then slowly moved into sitting position; this causes the clot to move into the utricular cavity. 2. SURGERY In patients refractory to liberatory meneuvers, singular neurectomy can be offered. Such selective neurectomy is diffi-cult to perform and carries a risk of permanent hearing disorder. Neurectomy has been replaced by plugging of the posterior canal. It is safer and more effective than nerve sectioning. 3. ANTIVERTIGINOUS THERAPY Drug treatment of BPPV with antivertiginous substances is neither possible nor sufficiently effective long term against the symptoms, because of the pathomechanism of the disorder. Patients who suffer from severe nausea after a sin-gle repositioning maneuver can be prescribed dimenhydrinate (100mg) half an hour before performing the liberatory maneuver.


Fig 2. Schematic drawing of Epley’s maneuver. (A) In the sitting position the head is turned horizontally 45 degrees to the affected (right) ear. (B) The patient is tilted approximately 105 degree backward into a slightly head hanging position, causing the clot to move in the canal. The pa-tient remains in this position for 1 minute. (C) The head is turned 90 degree to the unaffected ear. (D) The head and trunk continue turning an-other 90 degree towards the unaffected ear, causing the clot to exit the canal. The patient remains in this position for 1 minute. (E) The patient is moved into sitting position.


Fig 3. Schematic drawing of Brandt-Daroff exercises for a patient with BPPV. Eavh position should be held for 20-30 seconds and the exercises should be performed serially several times a day.

BPPV OF THE HORIZONTAL CANAL (h-BPPV) BPPV of the horizontal canal is less frequent than posterior BPPV but is still diagnosed too seldom. Its cardinal features are:

It can be induced by turning the head along the longitudinal axis of the supine body (either to the right or the left). This results in an ampullopetal deflection of the cupula (with more severe vertigo and nystagmus) when the head is turned to the side of the affected ear.

The nystagmus beats linear and horizontal to the undermost ear. Repeated positioning maneuvers cause little fatigue of the positioning nystagmus. The duration of the attacks and the nystagmus is longer because of the so called central storage mechanism of ve-

locity in the horizontal canal. The striking feature of horizontal BPPV, i.e., it does not fatigue, agrees with the assumption as does the general experi-ence that horizontal BPPV is difficult to treat by a single positioning maneuver. Treatment of Horizontal BPPV

1. Forced prolonged position on the healthy side: Vannuchi et al have adviced patients with h-BPPV to lie down on the healthy side for 12 hours to allow otolithic debris to gravitate to the vestibule, by maintaining the affected side uppermost.

2. 270 degree barbecue maneuver: this consists of turning the patients head and body from the supine position by three 90 degree step rotations (total 270) towards the unaffected side to assume the lying position on the affected side and then sit up (Fig 4).

3. 360 degree yaw rotation: Baloh proposed that treatment of h-BPPV can be achieved by this maneuver in which the patients head and body is rotated by 360 degrees in rapid 90steps and towards the unaffected ear. The time interval between each step is 30 seconds or until nystagmus subsides.

4. Liberatory maneuvers have been described in which the patient lies supine with head lifted by 30 degrees, turned to the affected side and maintained in that position for five minutes. The head is then turned as quickly as possi-ble 180 degrees to the other side and maintained there for five minutes. After the maneuver the patient is asked to avoid head shaking and not to lie down for the next 48 hours.


Fig 4. Positioning maneuver for treatment of h-BPPV. Each 90 degree head rotation is performed rapidly within a half second. Head positions are maintained for between 30 and 60 seconds until all nystagmus subsides. A. starting position. B. head rotation towards the unaffected ear. C. Body turned from supine to prone while head position is maintained. D. Head rotation to nose down position. E. Final head turn to unaf-fected ear down position. F. Sitting up position.

ANTERIOR CANAL BPPV (a-BPPV) This is rare and occurs as a consequence of treatment of posterior canal BPPV by single step maneuvers. Brandt Daroff exercise have been found to be effective in a- BPPV.


REFERENCES: Barany R, Cited by Dix R, Hallpike CS. Diagnose von krankheitserscheinungen im bereiche des otolithenapparatus.

Acta otolaryngol 1921; 2: 434-7. Dix R, Hallpike CS. The pathology, symptamatology, and prognosis of certain common disorders of the vestibular sys-

tem. Proc R Soc Med 1952;54:341-54. Schuknecht HF (1969) Cupulolithiasis. Arch Otolaryngol 90: 765-778.

Parnes ES, McClure JA (1991) Posterior semicircular canal occlusion in normal hearing ear. Otolaryngol Head Neck Surg 104: 52-57

Epley JM (1992) The canalith repositioning procedure: For treatment of benign paroxysmal positioning vertigo. Oto-

laryngol Head Neck Surg 10: 299-304. Brandt T, Daroff RB (1980) Physical therapy for benign paroxysmal positional vertigo. Arch Otolaryngol 106: 484-485. Brandt T, Steddin S, Daroff R.B. (1994) Therapy for benign paroxysmal positioning vertigo, revisited. Neurology 44.

796-800. Brandt T, Steddin S (1993) Current view of the mechanism of benign paroxysmal positioning vertigo: Cupulolithiasis or

canalolithiasis? J Vestib Res 3: 373-382. Levat E, van Melle G, Monnier P, Maire R (2003) Efficacy of the Semont maneuver in benign paroxysmal positional

vertigo. Arch Otolaryngol Head Neck Surg 129: 629-633. Semont A, Freyss G, Vitte E (1988) Curing the BPPV with a liberatory manoevre. Adv Otorhinolaryngol 42: 290-293. Herdman SJ, Tusa RJ, Zee DS, Proctor LR, Mattox BE (1993) Single treatment approaches to benign paroxysmal ver-

tigo. Arch Otolaryngol Head Neck Surg 119: 450-454. Gacek RR (1978) Further observations on posterior ampullary nerve transection for positional vertigo. Ann Otol Rhinol

Laryngol 87: 300-306. Baloh RW, Jacobson K, Honrubia V (1993) Horizontal semicircular canal variant of benign positional vertigo. Neurology

43: 2542 – 2549. Lempert Th, Tiel-Wilck K (1996) A positional maneuver for treatment of horizontal-canal benign positional vertigo, La-

ryngoscope 106: 476-478. Bisdorff AR, Debatisse D (2001) Localizing signs in positional vertigo due to lateral canal cupulolithiasis. Neurology 57:

1085-1088. Vanucchi P, Giannoni B, Pagnini P (1997) Treatment of horizontal semicircular canal benign paroxysmal positional ver-

tigo. J Vestib Res 7: 1-6.

Author details: Dr. Ankush Sayal, Senior Resident, Department of ENT & Head and Neck surgery, Maulana Azad Medi-cal College, Lok Nayak Hospital & Associated Hospitals.


MENIERE’S DISEASE

Introduction Background Ménière's disease, also known as idiopathic endolymphatic hydrops, is a disorder of the inner ear resulting in the clinical triad of ver-tigo, tinnitus and hearing loss. Prosper Ménière first proposed the disorder in 1861 in a series of papers in which he rejected the term apoplectic cerebral congestion, commonly used for vertigo, as this suggested that the pathology lay in the brain. He initially pro-posed the term inner ear glaucoma.1,2,3,4 Patients report an intermittent and progressive nature of the disease with a significant num-ber having spontaneous resolution. PATHOPHYSIOLOGY Endolymph is produced primarily by the stria vascularis in the cochlea and also by the planum semilunatum and the dark cells in the vestibular labyrinth.5 .Endolymphatic flow has been previously described as a "lake-river-pond" model. The endolymph flows from the endolymphatic fluid space (lake) through the vestibular aqueduct (river) to the endolymphatic sac (pond).6 More specifically, episodes of hydrops are probably caused by an increase in endolymphatic pressure that causes a break in the mem-brane separating the perilymph (a potassium-poor fluid) from the endolymph (a potassium-rich fluid). The resultant chemical mixture bathes the vestibular nerve receptors, leading to depolarization blockade and transient function loss. Sudden change in the vestibular nerve firing rate creates an acute vestibular imbalance, giving the sense of vertigo. Physical distention caused by the increase in endolymphatic pressure leads to mechanical disturbance of the otolithic organs. Be-cause the utricle and saccule are responsible for linear and translational motion detection, rather than angular and rotational accelera-tion, irritation of these organs may produce nonrotational vestibular symptoms. This physical distention causes mechanical disturbance of the organ of Corti as well. Distortion of the basilar membrane and of the inner and outer hair cells may cause hearing loss and tinnitus. Because the apex of the cochlea is wound tighter than the base, the apex is more sensitive to pressure changes than the base. This explains why hydrops affects low frequencies (located at the apex) more than high frequencies (located at the relatively wider base of the cochlea. Various extrinsic mechanisms are thought to contribute to the development of endolymphatic hydrops including infection, trauma, and allergens.7 Recent studies have questioned whether endolymphatic hydrops is a marker of disease rather than a cause. One study looking at tem-poral bones found all cases of patients with Ménière’s disease had hydrops in at least one ear. Hydrops was also found in patients who exhibited no signs of the disease.8

Race Ménière's disease primarily affects Caucasians,12 although this may be due to a reporting bias.13

Sex A slight increase may be noted in females compared to males (1.3:1).3 This may be biased due to more females seeking treatment. Age The peak incidence of Ménière's disease is in the 40- to 60-year-old age group.3 Ménière's disease has been described in children as young as 4 years and in elderly persons older than 90 years.6

Genetic factors

There is evidence that a COCH gene mutation was found in three families with Meniere’s disease (Olivera,C.A.and Braga,A.M.,1992),but in another study HLA class I and class II antigens were not found

to increase the susceptibility of developing Meniere’s disease (Koyama,S.et al.,1993).

Etiology • Multiple causes of dysfunction of the vestibular system are known. • No single entity is known to be responsible for Ménière's disease. It is currently thought to be due to overaccumulation of endo-lymph in the cochlear duct. Ménière's disease must be distinguished from other causes of endolymphatic hydrops such as post-traumatic, post-infectious, oto-syphilis, and Cogan's syndrome (interstitial keratitis).20 An autoimmune etiology has been postulated after it was found that there was an association with presence of thyroid autoantibodies in patients with Ménière's disease.21,22

GLOBAL VIEW Reported prevalence of Ménière's disease varies widely, from 15 per 100,000 in the United States to 157 per 100,000 in the United Kingdom.3 This difference in prevalence based on geographic area is likely due to reporting biases and not geographic patterns of disease. Bilateral disease is found in 10% of patients with Ménière's disease at initial diagnosis but, with disease progression, it may increase to over 40%.9 A genetic predisposition appears to exist.10

A familial predisposition seems to exist; approximately one half of all patients have a family history of the disease.


Differential Diagnosis Benign Paroxysmal Positional Vertigo

Inner Ear, Perilymphatic Fistula

CNS Causes of Vertigo

Inner Ear, Tinnitus

Inner Ear, Autoimmune Disease

Inner Ear, Evaluation of Dizziness

Inner Ear, Labyrinthitis

Migraine-Associated Vertigo

PERSONAL CLINICAL EXPERIENCE & MANAGEMENT Clinical presentation History The American Academy of Otolaryngology–Head and Neck Surgery Foundation (AAO-HNS) Committee on Hearing and Equilib-rium published guidelines on the clinical diagnosis of Ménière's disease in 1972, 1985, and, most recently, in 1995. According to these guidelines, Ménière's disease is defined as "recurrent, spontaneous episodic vertigo; hearing loss; aural fullness; and tinnitus. Either tinnitus or aural fullness (or both) must be present on the affected side to make the diagnosis."14

Vertigo ο Vertigo is a subjective sensation of motion while motionless. At least 2 definitive episodes of vertigo of at least 20 minutes duration must have occurred to make the diagnosis.14 ο Duration is usually several hours long. Horizontal or rotatory nystagmus is always present during attacks of vertigo.14 ο Symptoms are often accompanied with nausea, vomiting, and anxiety. Acute attacks may be accompanied with sudden falls without loss of consciousness. These are termed crises of Tumarkin or drop attacks.15 Most studies find the incidence of drop attacks to be less than 10%. In one case series, self-reporting of drop attacks was 72% among patients with diagnosis of Ménière's disease.16

In patients with the symptom of vertigo, Ménière's disease is the cause in 10%.17

Hearing loss ο Sensorineural hearing loss must be documented audiometrically in the affected ear at least once during the course of the disease. ο There may be fluctuation in the degree of hearing loss superimposed on a gradual decrement in function. ο Hearing loss affects low frequencies initially but at a later stage flattening of the curve is seen . Tinnitus and aural fullness ο Tinnitus is often nonpulsatile and may be described as whistling or roaring. ο It may be continuous or intermittent. Less than one third of patients present with all components of the triad at onset. Vertigo is the most common initial component with additional components appearing after a delay of months to years.13


TREATMENT ALGORITHM History of

• Fluctuating hearing loss • Tinnitus • Vertigo • Ear fullness

↓ Think of MENIERE’S DISEASE

PTA Low freq loss High freq loss ?presbycusis ECOG NIHL +ve -ve hearing aid evaluation Meniere’s does not r/o Meniere’s OR inactive Meniere’s Start medical therapy Fail to respond for 3-6 mnths SURGICALTHERAPY


Diet Dietary management of endolymphatic hydrops is based on the avoidance of substances that may trigger or exacerbate fluid pressure buildup in the inner ear. As with systemic hypertension, the goal of managing Ménière disease is to reduce the total volume of body fluid. This reduction, in turn, may reduce the fluid volume in the inner ear. • Avoidance of salt is one of the mainstays of therapy because sodium seems to play a major role in fluid retention in the inner ear. ο Patients should avoid foods with high sodium content (eg, pizza, preserved foods, smoked fish). ο Sodium nitrate is used in many preserved and smoked foods; therefore, these foods are high in sodium content. ο A rigid salt-restricted diet is recommended (ie, 1.5 g sodium), under the guidance of a nutritionist. ο Avoidance of other trigger substances has also been shown to help. The following should be avoided: caffeine; nicotine; chocolate, which has shown to be a potent trigger substance; tobacco; alcohol, particularly red wine and beer; foods with high cholesterol or triglyceride content; foods with high carbohydrate con-tent; and excessive sweets and candy. Activity Endolymphatic hydrops does not preclude regular activity. Exercise is recommended in moderation. Because of the unpredictable na-ture of the disease, balance-intensive dangerous tasks (eg, ladder use, precarious activities) should be avoided. Medical Care

Medical therapy is directed toward the mitigation of symptoms and/or their prevention. There has always been a debate regarding medical treatment. There are vast majority of drugs which have been tried ranging

from oral therapy to intratympanic therapies . In general, medications that decrease symptoms (eg, meclizine , droperidol, prochlorperazine diazepam, lorazepam , alprazolam )

only mask the vertigo. These masking agents are vestibulosuppressants and work by dulling the brain's response to signals from the inner ear.

Diuretics

Medications with diuretic-like properties (eg, hydrochlorothiazide and triamterene , hydrochlorothiazide , acetazolamide [Diamox], methazolamide ) decrease fluid pressure in the inner ear. These medications help prevent attacks but do not help after the attack is triggered.

Diamox can be started as 250 mg once a day after baseline electrolyte are done and repeated every 2 wks to keep a watch on the potassium level.

Diuretics help best in reducing aural fullness than relieving tinnitus or improving hearing loss Intravenous fluid support can also help prevent dehydration and replace electrolytes. Steroids

They have also been helpful in treating endolymphatic hydrops because of their anti-inflammatory properties. Steroids can reverse vertigo, tinnitus, and hearing loss, probably by reducing endolymphatic pressure. Steroids can be given orally, intramuscularly, or even transtympanically. Although the transtympanic route is controversial, it is

gaining wider acceptance throughout the otologic community. Oral prednisolone started 1mg/kg after breakfast for a period of 2 wks→ 0.75 mg/kg for 1 wk →0.5mg/kg for 1 wk →0.25mg/kg

for 1 wk . Before starting patients on steroids they must be evaluated for hypertension & diabetic status.

Aminoglycosides They are a class of antibiotics that were serendipitously discovered to be preferentially toxic to the vestibular (balance) end or-

gan. Destruction of the vestibular end organ renders the brain insensitive to fluctuations in inner ear pressure brought on by Ménière

disease. Given systemically, aminoglycosides affect both ears. Although aminoglycosides can be used to treat extremely severe bilateral Ménière disease, such treatment leaves the patient with

little or no balance function. The resulting complete loss of inner ear function (ie, Dandy syndrome) can be debilitating.


One innovation in the treatment of Ménière disease is the Meniett device.

The Meniett device delivers pulses of pressure to the inner ear via the tympanostomy tube. Although no one knows exactly why this works, some patients have symptomatic relief when the device is used on a daily basis. Because it is new, long-term results have not been fully evaluated. Histamine agonists Medications such as betahistine hydrochloride are widely used in Europe and South America. Although its mechanism of action is somewhat controversial, many have reported success with its use in mitigating symptoms of Ménière disease. Unfortunately, since betahistine is not US Food and Drug Administration approved, it is not discussed much in the United States. A new molecule Betahistine mesilate 6/12mg has been used & the dosage is less as compared to betahistine hydrochloride with more potency. Most of the studies are from Japan with no Indian studies are available . Betahistine hydrochloride 16mg tid or 24 mg bid is the therapeutic dose for patients with vertigo and gradually reduced to bid or od dose once the symptoms starts improving. BASIC AIM IS NOT TO MAKE PATIENT DEPENDENT ON VESTIBULAR SUPPRESENT DRUGS BUT TO ENCOURAGE THEM FOR REHABILITATION EXERCISES . LATEST GUIDELINES RECENT GUIDELINES IN MENIERE’S MEDICAL TREATMENT : 1. Betahistine Hydrochloride – 48mg three times a day. Even upto 480-540 mg can be given. 2. Treatment for Meniere’s disease is required upto a period of 3 – 4 months & majority of the cases of poor response to betahistine is because of inadequate treatment . Role of Prochlorperazine Known by the name of stemetil , it is used in acute crisis to control vomiting but should not be used round the clock for more than 5 – 7 days as it delays brain compensation. THE BEST VESTIBULAR SUPPRESENT IS diazepam, given when other drugs fail to control vertigo.

Surgical management Indications

• Surgery is indicated for Ménière disease that is refractory to medical management. Typically, failure to respond to 3-6 months of medical therapy is an indication of surgery. However, patients with severe debility may undergo surgery sooner.

• Any underlying medical causes for Ménière disease should be treated before surgical therapy is undertaken. The diseased ear must be clearly identified.

Historically, multitudes of clever surgical procedures have been invented, tested, and discarded. This article covers the 4 most

generally accepted management options: ♦ Endolymphatic sac decompression or shunt placement, ♦ Transtympanic medication perfusion, ♦ Vestibular nerve sectioning, ♦ Labyrinthectomy.


Transtympanic medication perfusion, intratympanic perfusion

Transtympanic medication perfusion, as shown in the image above, is becoming an established treatment modality. Popularized by Dr John Shea in 1995, the procedure is still evolving

Medications that may exert some effect on Ménière disease are delivered to the middle ear cavity through a myringotomy and the placement of tympanostomy tubes From there, medication is absorbed into the inner ear, presumably through the round win-dow membrane.

Innovations such as the round window microcatheter and Silverstein MicroWick were designed to channel medication flow di-rectly to the round window niche..

Transtympanic perfusion is considered a nondestructive procedure when steroids are used. Transtympanic steroid application is useful, particularly when patients have poor tolerance for the systemic adverse effects of

steroids. Furthermore, high concentrations can be administered by using this approach. Although results of long-term studies are not yet available, success rates appear to be favorable.

Transtympanic perfusion is considered a destructive procedure when aminoglycosides are used. When aminoglycosides are given transtympanically, their effects are concentrated in the affected ear rather than in both ears. Because streptomycin is difficult to obtain in the United States because of restrictions by the U.S. Food and Drug Administration

(FDA). gentamicin is more widely used. Early studies show an efficacy of about 90%. Some authors report substantial worsening of

hearing in 5-25% of patients. Vestibular nerve sectioning

Sectioning the diseased balance nerve can be the ultimate solution for patients with useful hearing in the affected ear. Although hearing and balance functions are housed in 1 common chamber within the inner ear, their neural connections to the

brain separate themselves into distinct nerve bundles as they course through the internal auditory canal. This anatomical sepa-ration facilitates the isolation and ablation of balance function without disturbing hearing function.

Advantages of vestibular nerve sectioning Vertigo-control rate of about 95-98%, and hearing preservation in the surgically treated ear, which is successful in about 95% of

patients. Risks of this procedure are those inherent to craniotomy and acoustic neuroma surgery. Facial-nerve damage, hearing loss, exacerbation of tinnitus and dizziness, CSF leakage, headaches, hemorrhage, and infection

(meningitis) are possible but rarely develop. After surgery, patients generally require 3-5 days of inpatient care. Adaptation to the surgical loss of 1 vestibular apparatus usually takes weeks to months. Vestibular rehabilitation during this period is often helpful. Labyrinthectomy

Labyrinthectomy has the advantage of a high cure rate (>95%) and is useful in patients in whom Ménière disease has destroyed their hearing on the affected side.

Labyrinthectomy involves ablation of the diseased inner-ear organs but does not require entry into the cranial cavity. Therefore, it is less complex than vestibular nerve sectioning.

Labyrinthectomy can be accomplished through 2 appro aches: transcanal and basic mastoidectomy . Transcanal approach

It is done through the external ear canal. First, a tympanomeatal flap is elevated. Next, a right angle pick is inserted through the oval window and maneuvered to disrupt and scramble the nerve tissues of the labyrinth.

Sometimes, a drill is used to connect the round and oval windows to improve exposure to the neuroepithelium. Mastoidectomy approach

Extension of the mastoidectomy by drilling through the semicircular canals allows for more complete ablation of the labyrinthine neuroepithelium than does the transcanal approach.

Labyrinthectomy is a bit less invasive than vestibular nerve sectioning. Craniotomy is not required; therefore, the risk of CSF leakage and meningitis is reduced. Patients typically require a few days of inpatient care. Adaptation to the surgical loss of 1 vestibular appa-ratus usually takes weeks to months. Vestibular rehabilitation during this period is also helpful.


ROLE OF VESTIBULAR REHABILITATION • Because of its fluctuating nature, vestibular therapy is not particularly useful as a primary treatment of Ménière disease. • However, it is useful in the rehabilitation of patients who have undergone vestibular ablation. In fact, vestibular rehabilitation is strongly recommended in those who have undergone aminoglycoside perfusion, labyrinthectomy, and vestibular nerve section.. References 1. Meniere P. Observations de maladies de I'oreille interne caracterisee par des symptomesde congestion apoplectiforme. Gaz Med de Paris. 1861;16:379. 2. Meniere P. Maladies de l'oreille interne offrant les symptomes de la congestion cerebraleapoplectiforme. Gaz Med de Paris. 1861;16:88. 3. Minor LB, Schessel DA, Carey JP. Ménière's disease. Curr Opin Neurol. Feb 2004;17(1):9-16.

4. Meniere P. Nouveaux documents relatifs aux lesions de l'oreille interne caracterisee pardes symptomes de congestion cerebrale apoplectiforme. Gaz Med de Paris. 1861;16:239. 5. Sajjadi H, Paparella MM. Meniere's disease. Lancet. Aug 2 2008;372(9636):406-14.

6. Paparella MM. Pathogenesis and pathophysiology of Meniére's disease. Acta Otolaryngol Suppl. 1991;485:26-35.

7. Paparella MM, Djalilian HR. Etiology, pathophysiology of symptoms, and pathogenesis of Meniere's disease. Otolaryngol Clin North Am. Jun 2002;35(3):529-45, vi. 8. Merchant SN, Adams JC, Nadol JB Jr. Pathophysiology of Meniere's syndrome: are symptoms caused by endolymphatic hy-drops?. Otol Neurotol. Jan 2005;26(1):74-81. 9. Kitahara M. Bilateral aspects of Meniére's disease. Meniére's disease with bilateral fluctuant hearing loss. Acta Otolaryngol Suppl. 1991;485:74-7. 10. Klockars T, Kentala E. Inheritance of Meniere's disease in the Finnish population. Arch Otolaryngol Head Neck Surg. Jan 2007;133(1):73-7. 11. Stephens D, Pyykko I, Varpa K, Levo H, Poe D, Kentala E. Self-reported effects of Ménière's disease on the individual's life: a qualitative analysis. Otol Neurotol. Feb 2010;31(2):335-8. 12. Morrison AW, Johnson KJ. Genetics (molecular biology) and Meniere's disease. Otolaryngol Clin North Am. Jun 2002;35(3):497-516. 13. Mancini F, Catalani M, Carru M, Monti B. History of Meniere's disease and its clinical presentation. Otolaryngol Clin North Am. Jun 2002;35(3):565-80. 14. Monsell EM. New and revised reporting guidelines from the Committee on Hearing and Equilibrium. American Academy of Otolar-yngology-Head and Neck Surgery Foundation, Inc. Otolaryngol Head Neck Surg. Sep 1995;113(3):176-8. 15. Baloh RW, Jacobson K, Winder T. Intratympanic gentamicin for Meniere's disease: effect on quality of life as assessed by Glas-gow benefit inventory. J Laryngol Otol. Oct 2006;120(10):827-31. 16. Kentala E, Havia M, Pyykko I. Short-lasting drop attacks in Meniere's disease. Otolaryngol Head Neck Surg. May 2001;124(5):526-30. 17. Bhattacharyya N, Baugh RF, Orvidas L, Barrs D, Bronston LJ, Cass S. Clinical practice guideline: benign paroxysmal positional vertigo. Otolaryngol Head Neck Surg. Nov 2008;139(5 Suppl 4):S47-81. . 18. White J. Benign paroxysmal positional vertigo: how to diagnose and quickly treat it. Cleve Clin J Med. Sep 2004;71(9):722-8. .

19. Bronstein A. Visual symptoms and vertigo. Neurol Clin. Aug 2005;23(3):705-13, v-vi.

20. Grasland A, Pouchot J, Hachulla E, Bletry O, Papo T, Vinceneux P. Typical and atypical Cogan's syndrome: 32 cases and review of the literature. Rheumatology (Oxford). Aug 2004;43(8):1007-15. . 21. Fattori B, Nacci A, Dardano A, Dallan I, Grosso M, Traino C. Possible association between thyroid autoimmunity and Menière's disease. Clin Exp Immunol. Apr 2008;152(1):28-32. Nacci A, Dallan I, Monzani F, Dardano A, Migliorini P, Riente L. Elevated antithyroid peroxidase and antinuclear autoantibody titers in Ménière's disease patients: more than a chance association?. Audiol Neurootol. 2010;15(1):1-6.

16. Kentala E, Havia M, Pyykko I. Short-lasting drop attacks in Meniere's disease. Otolaryngol Head Neck Surg. May 2001;124(5):526-30. 17. Bhattacharyya N, Baugh RF, Orvidas L, Barrs D, Bronston LJ, Cass S. Clinical practice guideline: benign paroxysmal positional vertigo. Otolaryngol Head Neck Surg. Nov 2008;139(5 Suppl 4):S47-81. . 18. White J. Benign paroxysmal positional vertigo: how to diagnose and quickly treat it. Cleve Clin J Med. Sep 2004;71(9):722-8. . 19. Bronstein A. Visual symptoms and vertigo. Neurol Clin. Aug 2005;23(3):705-13, v-vi. 20. Grasland A, Pouchot J, Hachulla E, Bletry O, Papo T, Vinceneux P. Typical and atypical Cogan's syndrome: 32 cases and review of the literature. Rheumatology (Oxford). Aug 2004;43(8):1007-15. . 21. Fattori B, Nacci A, Dardano A, Dallan I, Grosso M, Traino C. Possible association between thyroid autoimmunity and Menière's disease. Clin Exp Immunol. Apr 2008;152(1):28-32. 22. Nacci A, Dallan I, Monzani F, Dardano A, Migliorini P, Riente L. Elevated antithyroid peroxidase and antinuclear autoantibody titers in Ménière's disease patients: more than a chance association?. Audiol Neurootol. 2010;15(1):1-6.

Author details: Dr. Sumit Mrig. Senior Consultant, Department of ENT & Cochlear Im palnt Surgery, Primus Super-speciality Hospital, New Delhi.



Q 1 . A 44 yr/f having slowly progressive imbalance with vertical oscillopsia for the

past 5 yrs. On examination there is downbeat nystagmus present during downward & lat-

eral gaze & is worse in the morning. The patient is suffering from ?

a. Vestibular deficit

b. Cerebellar lesion

c. Episodic ataxia type 2

d. Phobic postural vertigo.

Q 2. The treatment for the above cause of vertigo is

a. Betahistine 16mg 8 hrly

b. 3,4 diaminopyridine

c. Rehabilitation

d. Beta blocker

Q 3. 26 yr/m c/o vertigo with gait & postural with normal neurological examination .

vertigo attacks get worse in crowds & departmental store & improve in the night . the

patient is suffering from ?

a. B/l vestibulopathy

b. Cerebellar lesion

c. Phobic postural vertigo

d. Demyelinating disease.

Q 4. The treatment in the above cause is

a. Betahistine 24 mg bd

b. Psycho educational therapy & desensitization

c. Rehabilitation

d. Anxiolytics

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Ent Trends, Vol2, Issue 2, April 2011