PERIPHERAL, VERTIGOR. BHARGAVA, Senior ResidentP. GHOSH, Professor and Head,All India Institute of Medical Sciences,New Delhi - 110029.

The Present study was carried out in order to evaluate the efficacy of warm monothermaltest in patients of peripheral vertigo. Thirty patients were diagnosed to have peripheral ver-tigo based on clinical, audiometric and vestibular evaluations. The vestibular evaluation wasdone using clinical bithermal caloric test (Fitzgerald & Hallpike), ice cold caloric (Kobark)and bithermal test with ENG recordings. The data of clinical evaluations were comparedwith the normative one, obtained, from a control population consisting of 15 subjects. Thesensitivity of warm monothermal test following clinical evaluation and with ENG was 84%and 79% respectively. The sensitivity of the ice cold caloric test was 71% thus suggestinga greater sensitivity of warm monothermal test. Warm monothermal test is a cost effectivescreening procedure for patients of peripheral vertigo.

INTRODUCTION

Caloric test happens to be one of the mostimportant clinical methods of investigating theequilibrial sense organ and its central neuralsubstrates. Despite being unphysiological andnon-reflective of the normal response of vestibularsubsystem in any way because of its being asuprathreshold test, it has immense diagnosticvalue. The aim of any test procedure is itssimplicity, being less time consuming, havingminimal unpleasant effects, simplicity ofinterpreting the results and test/retestreproducibility with reliability. For these reasonssome simpler techniques have being used inreplacement of the conventional bithermal calorictest. A monothermal caloric test, as comparedto standard bithermal caloric test, is a step inthat direction. Hart (1965) and Bernstein (1965)suggested that warm monothermal test wouldshorten the time of examination and be ableto show common abnormalities. Barber et al(1971) were first to investigate the efficacy ofa warm monothermal stimulation using ENGtechnique.

This study has attempted at assessing theresults of hot caloric test as a reliable param-eter for evaluating patients of vertigo withperipheral localisation and compare it with kobrak

minimal cold caloric test and standard bithermaltest clinically and using electronystagmography.

MATERIALS & METHODS

The present study was conducted on fortyfive subjects which were divided into two groups:

a) Normal Subjects - which constituted thecontrol group.

b) Patients with peripheral vertigo hencecalled the pathologic group.

Control Group : This group comprised offifteen young subjects. They were freeof any ear complaints and vertigo. Athorough history and general physicalexamination were followed byOtolaryngological, audiological and neuro-otologic investigations viz.

1. Pure tone audiometry.

2. Clincical bithermal caloric testing andKobrak's minimal cold caloric test.

3. Standard electronystagmographic(bithermal) evaluation.

There were 12 males and 3 females betweenthe age group of 16-35 years.

Pathological Group: This group was con-stituted by 30 patients, diagnosed to have

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investiperipheral vertigo on the basis of history,clinical examination, audiometry and vestibularevaluations. These patients also underwentinvestigations in order to rule out a retrocochlearpathology where ever indicated. The test batteryincluded special audiometric tests viz; SISI,difference limen, and Tone Decay, X-ray of theinternal auditory, meatus, Brainstem evokedresponse audiometry , CT of the temporal boneand in patients with a high suspicion, Magneticresonance imaging was done.The patients rangedbetween the age 19 years to 70 years.Therewere 20 males and 10 females. There were 16patients complaining of impairment of hearingout of whom 13 had sensorineural and 3 hadconductive hearing loss.

The clinical diagnosis of the patients in thisgroup were as follows :

Vascular 9Vestibular Neuronitis 4Meniere's 3Post-head injury 2Otospongiosis 2Age related 2Ototoxicity 2Cervical spondylosis 1Benign Paroxysmal positional vertigo 1

Cause Undetermined 4

Vestibular Evaluation : The clinical bithermaltest was carried out as described by Fitzgeraldand Hallpike (1942). Having induced the nystag-mus the duration of nystagmus i.e. the time periodbetween the start of stimulus and the end of nystagmuswas noted. An interval of 5 minutes betweensuccessive tests was given with a view to avoidingpossible vestibular fatigue or adaptation.

Cold Caloric Test : The test was performedwith ice cola water as advocated by Kobrak withsome modifications. The patient was seated on achair with a head rest. First the horizontal canalwas stimulated with the head tipped at 60 degreesbackward and then vertical one by putting thehead in erect position with a forward inclination of30 degrees, 5 ml, of water was slowly irrigatedtowards the postero-superior quadrant of the tym-panic membrane and the adjoining canal wall overa period of half minute from a 40 ml. syringe witha 21 gauge needle through an ear speculum andif no reaction was noted within 45 secs, 10ml. ofwater was irrigated. If necessary the quantity ofwater was increased by 5-10 ml, every time tillthere was no reaction with 40 ml. of water".

As soon as the nystagmus started the patientwas asked to close the eyes and tested for pastpointing to see if there was anydissociation or bilateral conjugate deviation ofthe superior extremeties. Then the nystagmuswas noted carefully as to its amplitude,character, direction and duration. The subjectivesensation of vertigo were enquired and thevegetative reactions were looked for. The headwas then tipped forward 30 degrees and thenystagmus was carefully scrutinised for any changeof character (whether rotating or horizontal),direction and dissociation. Normally stimulationof the horizontal canal gives horizontal nystag-mus and vertical ones, rotatory nystagmus infrontal plane both to the opposite side.

Electronystagmography was carried out tonote the following:

a. Spontaneous nystagmus

b. Deviation maintenance nystagmus

c. Optokinetic nystagmus

d. Positional nystagmus

e. Pendular eye tracking test

f. Nystagmus after bithermal claoric stimu-lations.

All with eyes closed-lights off, then eyes openlights off and later eyes open lights on.

OBSERVATION

The normative data obtained from the control,group showed that the difference between rightand left ear was not significant in warm caloric(44 degrees C), Cold caloric (30 degrees C) and,ice cold caloric (Kobrak's) clinical test.

The clinical test procedure showed twocharacteristic features:

1. The cold caloric test both with 30 degreesC and ice cold water had more severe responsesthan warm caloric test.

2. The cold caloric test was more uncom-fortable to the patient than the warm one in thecontrol group.

In the pathological group of patients the crite-ria for hypofunction was taken as greater than15% difference between the two ears. The norma-tive data for the clinical test were obtained fromcontrol group and for ENG the parameters thatare being used in our laboratory i.e. (R) 44 de-

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rwi L,arvnc i est in ranenrs wirn renpneral verugo — N. tmargava, er ar.

grees C (22-56) (R) 30 degrees C (26-63), (L) 44degrees C (23-50) & (L) 30 (25-63) beats/30seconds. Using these criteria it was seen thatthe correlation between the various parameterswas best in the group of patients labelled asMeniere's disease (100%). In other groups thecorrelation was not so accurate possibly due tothe multiplicity of the causative factors. In thepatient of Benign Paromysmal Positional Vertigothere was normal vestibular functioning withbithermal test but with cold caloric (Kobrak's)test, there was, hypofunctioning of the left verti-cal canals. There was, in addition, a left posi-tional nystagmus. This is a unique combinationof left positional nystagmus with hypofunctioningof left vertical canal which should have been ir-ritative in this lesion. We have not done the testfor utricular function which is supposed to behyperactive in cupulolithiasis in the affected earin undermost position. When all the 30 patientsare considered the sensitivity of the clinical warmmonothermal test was 84%.

The sensitivity of ice cold caloric test was71% and warm monothermal test using ENGwas 79%. There was insignificant differencebetween the warm monothermal test using clinicallevaluation and ENG.

(DISCUSSION

It was Hart (1965) and Bernstein (1965) whosuggested that caloric test could be shortenedusing warm water only. They showed that majorityof the abnormal patterns, could be shown withwarm claoric test only. The warm stimulus waschosen because it generated a response to-wards the worse ear in a directional prepon-derance of peripheral origin. The warm stimulushas been shown to be more physiological ascompared to the cold stimulus because of theconvection currents generated in the endolymphby warm stimulus impinge on the physiologicallypositive side of the ampulla' and increase theresting potential of the vestibular nerve undertesting. The warm stimulus was also shown tohave better correlation with vestibular and auditoryfindings in patients of Meniere disease 7 . Theefficacy of the warm monothermal test as ascreening procedure was validated usingelectronystagmographic control'. It was sug-gested by Jacobson et al (1985) that warm

monothermal test could predict normalbithermal response with 97% accuracy andthe authorfurther advised to generate personalnormalite data in each laboratory for com-parison.

In our study it was seen that there was80% correlation between warm monothermaltest and bithermal test. This probably in-dicates that one important parameter of coldcaloric stimulation has been excluded so thatthe complete picture of labyrinthine functionis missing which can be brought about bytemperature above and below body tem-perature. The sensitivity of 80% is of highsignificance and can be used as a screeningtest even in a small hospital where the facilitiesfor sophisticated tests are not available. Itwas further seen in our study that there washigher reliability and correlation withhypofunction of canal elements. In our testprocedure we did not find any hyperexcitabilitywith warm stimulus although it is well knownthat hyperactivity can be seen with cold calorictest°. Although it appears to be a fairly reliabletest for screening, the important aspect ofdirectional preponderance and vestibular re-cruitment and decruitment3 cannot be as-sessed. The cold caloric test appeared tobe more unpleasant with warm stimulationhas been our observation in this study. Nohyperactivity with warm stimulus was no-ticed in peripheral lesion which has beenseen in central lesion. This can broadly localiselesion although it would require more inten-sive studies.

SUMMARY

The sensitivity of warm caloric test inpatients of peripheral vertigo using clinicalobservation with duration of nystagmus asthe parameter and with ENG was superioras compared to,' ice cold caloric test.

The cold caloric tests were moreunpleasant to the patients as compared towarm monothermal test. There was aninteresting observation of left positionalnystagmus with hypofunction of left verticalcanal evident on ice cold caloric test ina patient of benign paroxysmal positionalvertigo.

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REFERENCES

1. Barber Hugho, Wright Grace and Demannule Fred (1971): The hot caloric test as a clinicalscreening device. Arch Otolaryngol, 94:335-337.

2. Bernstein Lestre (1965) : Simplification of clinical caloric test. Arch Otolaryngol, 81:347-349.

3. Ghosh P and Kacker SK (1979) : Vestibular recruitment and decruitment. Acta Otolaryngologica,88: 227-234.

4. Ghosh P and Sen OK (1970) : Nystagmus and brain lesions, Neurology India,28: 236-240.

5. Hallpike CS (1967) : Some types of ocular Nystagmus and their neurological mechanism.Proceedings of Royal Society of Medicine, 60: 1043052.

6. Hart Cacil WJ (1965): The value of the hot caloric test, Laryngoscope, 75: 302-315.

7. Hinchcliffe R (1967) : Validity of measures of caloric test response. Acta Otolaryngologica,63: 69-73.

8. Jacobsen Gary P, Means Eungene D (1985): Efficacy of a monothermal warm water caloricscreen test. Ann. Oto, Rhinol, Laryngol, 94: 377-381.

CLOSURE OF PERSISTENT CENTRAL PERFORATIONS OFTYMPANIC MEMBRANE USING 1% HYALURONIC ACID

Shiv Kumar, Senior Registrar,A.K.Gupta, Professor & Head,Department of E.N.T.,R.N.T. Medical College,UDAIPUR-313 001

Twenty five dry, small or medium sized persistent central perforations were treated by localapplication of 1% hyaluronic acid after excision of the perforation rim. The duration of theperforation ranged from two months to forty years. 88 percent perforations healed with 16 ± 4(S.D.) days using 5 ± 1.6 (S.D.) applications. Hyaluronic acid treatment of dry tympanicmembrane perforations not exceeding one quadrant seems to be an alternative to surgicalmyringoplasty.

Key words : Persistent Central Perforation; Hyaluronic Acid

INTRODUCTION

The tympanic membrane may become perfo-rated in various ways, e.g. by foreign bodies orsurgical instruments inserted into the external auditorycanal, or by a variety of factors which producesudden compression of the tympanic membrane

(a box on the ear hand slap, force-ful syringing).Central perforations as a sequelae of acute sup-purative otitis media, chronic benign otitis mediaand myringotomies are quite common.

In experimental animal, proliferation of stratifiedsquamous epithelium at the edges of a per-

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