www.bjorl.org
Brazilian
Journal
of
OTORHINOLARYNGOLOGY
ORIGINAL
ARTICLE
Subjective
visual
vertical
after
treatment
of
benign
paroxysmal
positional
vertigo
夽
Maristela
Mian
Ferreira
a,∗,
Maurício
Malavasi
Gananc
¸a
b,
Heloisa
Helena
Caovilla
caUniversidadeFederaldeSãoPaulo(Unifesp),EscolaPaulistadeMedicina(EPM),ProgramadePós-graduac¸ãoemDistúrbiosda
Comunicac¸ãoHumana,CampoFonoaudiológico,SãoPaulo,SP,Brazil
bUniversidadeFederaldeSãoPaulo(Unifesp),EscolaPaulistadeMedicina(EPM),DepartamentodeOtorrinolaringologia,São
Paulo,SP,Brazil
cUniversidadeFederaldeSãoPaulo(Unifesp),EscolaPaulistadeMedicina(EPM),DisciplinadeOtologiaeOtoneurologia,São
Paulo,SP,Brazil
Received31May2016;accepted29August2016 Availableonline28September2016
KEYWORDS
Benignparoxysmal positionalvertigo; Innerear; Utricle;
Posturalbalance
Abstract
Introduction:Otolithfunctioncanbestudiedbytestingthesubjectivevisualvertical,because thetiltoftheverticallinebeyondthenormalrangeisasignofvestibulardysfunction.Benign paroxysmal positional vertigois adisorder ofoneor more labyrinthinesemicircular canals causedbyfractionsofotolithsderivedfromtheutricularmacula.
Objective: Tocomparethesubjectivevisualverticalwiththebuckettestbeforeand immedi-atelyaftertheparticlerepositioningmaneuverinpatientswithbenignparoxysmalpositional vertigo.
Methods:Weevaluated20patients.Theestimatedpositionwhereafluorescentlinewithina bucketreachedtheverticalpositionwasmeasuredbeforeandimmediatelyaftertheparticle repositioningmaneuver.Dataweretabulatedandstatisticallyanalyzed.
Results:Beforerepositioningmaneuver,9patients(45.0%)hadabsolutevaluesofthesubjective visualvertical abovethereferencestandardand2(10.0%)afterthemaneuver;themeanof the absolute values ofthe vertical deviation was significantly lower after theintervention (p<0.001).
夽 Pleasecitethisarticleas:FerreiraMM, Gananc¸a MM,Caovilla HH.Subjectivevisual verticalaftertreatmentofbenignparoxysmal
positionalvertigo.BrazJOtorhinolaryngol.2017;83:659---64. ∗Correspondingauthor.
E-mail:[email protected](M.M.Ferreira).
PeerReviewundertheresponsibilityofAssociac¸ãoBrasileiradeOtorrinolaringologiaeCirurgiaCérvico-Facial.
http://dx.doi.org/10.1016/j.bjorl.2016.08.014
1808-8694/©2016Associac¸˜aoBrasileiradeOtorrinolaringologiaeCirurgiaC´ervico-Facial.PublishedbyElsevierEditoraLtda.Thisisanopen
Conclusion:Thereisareductionofthedeviationsofthesubjectivevisualvertical,evaluatedby thebuckettest,immediatelyaftertheparticlerepositioningmaneuverinpatientswithbenign paroxysmalpositionalvertigo.
© 2016 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Published by Elsevier Editora Ltda. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/by/4.0/).
PALAVRAS-CHAVE
Vertigemposicional paroxísticabenigna; Orelhainterna; Utrículo;
Equilíbriopostural
Verticalvisualsubjetivaapóstratamentodavertigemposicionalparoxísticabenigna
Resumo
Introduc¸ão:A func¸ãodootólitopodeserestudadapormeiodetestesdaverticalvisual sub-jetiva,porque ainclinac¸ão dalinha vertical alémdafaixa normalé um sinalde disfunc¸ão vestibular.Avertigemposturalparoxísticabenignaéumdistúrbiodeumoumaiscanais semi-circulareslabirínticoscausadoporfrac¸õesdeotólitosderivadosdamáculautricular.
Objetivo:Compararaverticalvisualsubjetivacomotestedobaldeanteseimediatamenteapós amanobradereposicionamentodepartículasempacientescomvertigemposicionalparoxística benigna.
Método: Foramavaliados20pacientes.Aposic¸ãoestimada,ondeumalinhadefluorescência dentrodeumbaldeatingiaaposic¸ãovertical,foimedidaanteseimediatamenteapósamanobra dereposicionamentodepartículas.Osdadosforamtabuladoseanalisadosestatisticamente.
Resultados: Antesdamanobradereposicionamento,9pacientes(45,0%)apresentaramvalores absolutosdeverticalvisualsubjetivaacimadareferênciapadrãoe2(10,0%)depoisdamanobra; amédiadosvalores absolutosdodesvioverticalfoisignificativamentemaisbaixa depoisda intervenc¸ão(p<0,001).
Conclusão:Háuma reduc¸ãodosdesvios davertical visual subjetiva,avaliada pelotestedo balde,imediatamenteapósamanobradereposicionamentodepartículasempacientescom vertigemposicionalparoxísticabenigna.
© 2016 Associac¸˜ao Brasileira de Otorrinolaringologia e Cirurgia C´ervico-Facial. Publicado por Elsevier Editora Ltda. Este ´e um artigo Open Access sob uma licenc¸a CC BY (http:// creativecommons.org/licenses/by/4.0/).
Introduction
Theperceptionoftheverticalpositiondependsonthe inte-grationofvestibular,proprioceptiveandvisualinformation; however, it hasnot yet been determined howand where in thecerebral cortex thevestibular informationfor spa-tialperceptionisprocessed.1Thethreesemicircularcanals
aresensitivetoangularaccelerations,andtheutricularand saccularmaculae,withtheirotoliths,aresensitivetolinear accelerations;thecorticalotolithafferentsprovidespatial orientation,perceptionofmovement,andmental represen-tationofthebodyinspace.2
Thebenignparoxysmalpositionalvertigo(BPPV), recog-nizedasacommoncauseofvertigowithahigherprevalence infemalesandintheelderly,inmostcasesisunilateraland idiopathic.Itischaracterizedbyepisodesofsuddenvertigo and/orpositionalnystagmus,ofshortduration,andmaybe accompaniedbynausea;itoccurswhenthereisachangeof positionoftheheadduetootolithfractionation of utricu-larmacula,andthedisplacementoftheseparticlestothe semicircularcanals.3---8
ThediagnosisofBPPVisbasedonclinicalhistoryandis establishedbyacomplaintof vertigowithvisualizationof nystagmusduringpositionalmaneuvers,usuallyparoxysmal andfatigable,andexhibitinglatency.Thecharacteristicsof
thepositionalnystagmuselicitedbytheDix-Hallpiketest9
orthetestofheadrotation10identifytheaffectedlabyrinth
andsemicircularcanal.10
Thereareseveralmethods toassess thevestibular sys-tem.The testthat evaluatesthe abilitytojudgewhether objectsareuprightiscalledsubjectiveverticalvisual(SVV). This test can indicate impairment of spatial orientation in patients with peripheral11 and central12,13 vestibular
disorders, especially in acute unilateral otolith dysfunc-tions, indicating thatthe greaterthe deviation,the more acute or more extensive the lesion.14 The direction of
SVV tilt is usually to the same side in unilateral periph-eral(labyrinthand/orvestibularnerve)orpontomedullary (vestibularnuclei)lesions,andtotheoppositeside ofthe affectedonesinunilateralpontomesencephaliclesions,and canbetothesamesideortheoppositesideinthalamicor dentatenucleuslesions.15
bucketmethod,appliedinBrazil,showedthatthehighest concentrationofabsolutevaluesoftheverticaldeviations reachedavalue of3inadultsandhealthyelderly individ-uals,regardlessofgender,anddidnotincreasewithage.17
The limit of SVV deviation with the bucket method con-sidered normal in adultsand elderly,17 and in the elderly
andoldest,18,19 issimilartothelimit ofSVVusedinother
methods.20,21
In patients with BPPV that were evaluated by differ-entmethods,SVVdeviationsweredifferent22---24orsimilar25
to the control group deviations. Deviations of SVV were normal,23 abnormal20,26 or were near normal limits11 and
werealwaysorofteninclinedtowardtheaffectedside11,20,23
orinclinedtothehealthyside.26 Withthebucketmethod,
abnormal deviations of SVV were frequent, and often occurredtotheaffectedside.27
The low cost, easy evaluation of SVV with the bucket test,andthecontradictory reportsintheliteratureabout the findings in patients withBPPVmotivated theinterest in expanding the experience with this diagnostic method beforeandaftertreatmentofthisdiseasewithmaneuvers forrepositioningparticles.
Theobjectiveofthisresearchistocomparethe subjec-tiveverticalvisualthroughthebuckettestbeforeandafter particles repositioning maneuver in patients with benign paroxysmalpositionalvertigo.
Methods
ThisstudywasapprovedbytheResearchEthicsCommittee oftheinstitutionunderNo.733.154/2014.Allparticipants receivedinformationabouttheresearchanditsobjectives throughanexplanatoryletter,andsignedtheInformed Con-sentbeforetheinvestigationbegan.
Inthiscross-sectionalstudy,thesampleconsistedofadult maleorfemalepatientsdiagnosedwithBPPV.
Thecriterionforinclusionofpatientswasthediagnosis ofBPPV,madebytheotolaryngologist,basedonclinical his-toryandthepresence ofvertigoandpositionalnystagmus whenundergoingDix-Hallpiketest9andheadrotation,10to
identifytheimpairedlabyrinth(right,leftorboth)andthe semicircularcanal(posterior,anteriororlateral).
We excluded patients withinability tounderstand and followsimpleverbalcommands;severevisualimpairment, oranywhosevisionwasnotcompensatedwiththeuseof cor-rectivelenses;neurologicaland/ormentaldisorders;other vestibulardisorders,alcoholintake24hpriortoevaluation; thoseondrugsthatactonthecentralnervoussystemorthe vestibularsystem;andthosehadundergonerehabilitation forbodybalanceinthelastsixmonths.
Patientsunderwent,successivelyonthesameday,history taking,investigation forvertigo andpositionalnystagmus, andevaluation ofSVV withthe bucketmethod16,17 before
andimmediatelyafterperforminga singleparticle reposi-tioningmaneuver.
The investigation for vertigo and positional nystagmus in Dix-Hallpike tests9 andhead rotation10 determined the
clinical diagnosis of patients. The presence of nystagmus at right Dix-Hallpike test indicated right labyrinth BPPV, andatleftDix-Hallpikeindicated leftlabyrinth BPPV. Tor-sional and vertical up-beatnystagmus indicated posterior
canalinvolvement;thetorsionalandverticaldown-beat nys-tagmusindicated anteriorcanal involvement. Inthe head rotation test to the right and left sides, more intense geotropic horizontal nystagmus indicated an impairment of the lateral canal on the same side, and more intense ageotropic horizontal nystagmus indicated impairment of thelateralcanalontheoppositeside.10
Dependingontheidentificationoftheimpaired semicir-cular canal,the otolaryngologist selectedEpley’s particle repositioningmaneuver28 tobeperformed incasesof
pos-teriorcanalBPPV,andLempert’smaneuver29forthelateral
canalBPPV.
BinocularassessmentofSVVusedabucket.30Atthe
inter-nalbottomofthebucket,afluorescenttapewasarranged rectilinearlyandperfectlyalignedwiththegroundzeroofa protractorpositionedontheoutsidebottomofthebucket, andthetrueverticalrelativetotheEarth.
Patients, sitting with their head held upright and the visualfieldcompletelyintothebucket,wereinstructedto lookatthefluorescentlineinsideit.Thebucketwasrotated atrandombytheexaminerclockwiseandcounterclockwise. Then the examiner slowly turned the bucket toward the zerodegreeposition.Patientssaid‘‘stop’’whenthe fluo-rescentlinereached the verticalposition.Tenrepetitions wereperformed,fiveclockwiseandfiveanti-clockwise.The angulardeviationfromtheverticalpositionwasmeasured indegreesfromthescalelocatedoutsidethebucket.The meanofabsolutevaluesofdeviationsfromtrueverticalof ten repetitionsof the procedure wascalculated for each patientbeforeand afterthe repositioning maneuver. Val-uesabove 3,to theright or tothe left,were considered abnormal.17---19 Thedirectionoftheslopeineachcase was
determined by summing the values of all 10 repetitions, consideringthepositiveornegativesign.18Deviationstothe
rightweredefinedaspositive(bucketrotatedclockwise rel-ative tothe patient),and deviations tothe left negative (bucketrotated counterclockwiserelativetothe patient). The sumof the deviations tothe right (positive) and left (negative)thatwereequaltozerodefinedalackof preva-lenceinonedirectionovertheother.
Dataoftheinvestigationwerehandledexclusivelybythe main investigatorto ensurethe right toconfidentiality of information.
Adescriptivestatisticalanalysistocharacterizethe sam-plewasperformed.Forquantitativevariables,theminimum and maximum values were observed, and the mean val-ues, medians and standard deviations were calculated. Forqualitativevariables,absoluteandrelativefrequencies were calculated. The Wilcoxon test was used to com-pareSVVmeasurementsatdiagnosisandimmediatelyafter the repositioning maneuver. The power of the test was calculated, showing that the sample size was sufficient. Analyses were performed using SPSS (Statistical Package for Social Sciences)version 19; the significance level was 0.05(5%).
Results
Table1 Absolutevaluesandstatisticaldataofverticaldeviationsanditsdirectionbeforeandaftertherepositioningmaneuver inpatientswithbenignparoxysmalpositionalvertigo.
Patients Semicircularcanal affectedinBPPV
Beforethemaneuver Afterthemaneuver
Meanofabsolute valuesinSVV(in degrees)
Prevalent directionofSVV deviation
Meanofabsolute valuesofSVV(in degrees)
Prevalent directionofSVV deviation 1 Lposterior 3.6 Right 3.1 Right 2 Lposterior 3.7 Right 1.8 Right 3 Lposterior 2.6 Left 1.0 Left 4 Lposterior 3.1 Left 1.4 Left 5 Lposterior 2.2 Right 1.2 Right 6 Rposterior 2.8 Right 1.1 Left 7 Rposterior 3.6 Right 2.2 Right 8 Rposterior 1.3 Left 0.5 Left 9 Rposterior 4.6 Right 2.8 ---10 Rposterior 3.5 Right 1.7 Right 11 Lposterior 2.3 Right 1.7 Right 12 Rposterior 3.3 Left 2.0 ---13 Lposterior 1.7 Left 0.2 ---14 Rposterior 1.5 Left 1.3 Left 15 LateralD 2.1 Right 0.5 Right 16 Lposterior 2.4 Right 1.4 Right 17 Lposterior 2.3 Right 1.0 Right 18 Rposterior 5.3 Right 5.4 Right 19 Rposterior 3.5 Left 1.4 Left 20 Lposterior 1.5 Left 1.1 Left
Mean 2.8 1.6
Median 2.7 1.4
Minimumvalue 1.3 0.2 Maximumvalue 5.3 5.4 Standarddeviation 1.1 1.1 Wilcoxontest p<0.001
R,right;L,left;---,noprevalenceofdirection.
Theinvolvementoftheleftposteriorsemicircularcanal was identified in 10 cases, the involvement of the right posterior semicircularcanal in nine, andthe right lateral semicircularcanalinone.
Table1showsacomparisonoftheabsolutevaluesofSVV beforeandaftertherepositioningmaneuverin20patients withBPPV.
Beforetherepositioningmaneuver,ninepatients(45.0%) hadabsolutevaluesofSVV abovethereferencestandard: abnormal deviations to the same side of the affected labyrinth in BPPV occurred in 5 cases (25.0%) and tothe oppositesidein4(20.0%).Elevenpatients(55.0%)had devia-tionsoftheabsolutevaluesofSVVinthereferencestandard. Afterthe repositioning maneuver,two patients(10.0%) hadabnormaldeviations ofthe absolute valuesofSVV, in thesamedirectionobservedbeforethemaneuver;15cases (75.0%)hadnormaldeviations fromtheabsolutevaluesof SVV,14(70.0%)in thesamedirection,and 1(5.0%)inthe oppositedirectioncomparedtothatseenbeforethe maneu-ver; 3 cases (15.0%) did not show any prevalence of one directionovertheother.
Comparing SVV deviations before and after the repo-sitioning maneuver, the mean of absolute values of the
vertical deviations in 20 cases of BPPV in the reference standard was significantly lower after the intervention (p<0.001).
Discussion
VertigotriggeredbyheadmovementsinBPPVisexplainedby themigrationofcalciumcarbonateparticlesresultingfrom thefractionationofotolithsoftheutricularmacula.3,4The
mechanicalmaneuversofrepositioningthedebrisofotolith aimtoreturntheparticlestotheutriclethroughasequence ofmovementsoftheheadandbody.10,28
SVVtestsevaluate theotolithfunction, especiallythat oftheutricularmacula.14,23ThereisevidencethatBPPVis
associatedwithutriculardysfunction,possiblydueto degen-eration of the utricular macula.25 Deviations of SVV were
checkedbymeans ofalight barin87.5% ofpatientswith acuteBPPVcomparedtoacontrolgroup.22Withthebucket
Inthisresearch,theabnormaldeviationofabsolute val-ues of SVV was not necessarily to the same side of the affected labyrinth, a finding that is consistent withsome research20,26,27andnotconsistentwithothersthatobserved
SVVdeviations only tothe BPPVside.11,20,23 Attemptingto
explainthefindingofdeviationstothecontralateralsideof BPPV,itwassuggestedthattheareaoftheutricularmacula affectedbythelossofotolithscouldbeincellfieldsthatare sensitivetoipsilateralorcontralateralcephalicinclinations; theotolithdisordercouldbebilateral,butwouldonly mani-festasaunilateralBPPV;orthatvisuovestibularintegration structuresdevelopedacorrectionbymovingSVV contralat-erally tomaintainharmony between visual andvestibular information.20
Almosthalf ofthisseriesof patientswithBPPV(45.0%) showed abnormal absolute deviations of SVV during the acuteperiodof thedisease.Theliterature describes vari-able results in the acute phase of the disease. With the bucketmethod, 80.9%of thecases ofBPPVshowed abso-lutedeviationsofabnormalSVV,27 andwithothermethods
abnormaldeviationsofSVVinBPPVwerefoundinonly10.0% ofthecases,26andin53%ofcases11andin16.4%ofpatients
diagnosedwithrightBPPVandin14.2%ofpatientswithleft BPPV.20
Justa littlemorethan halfof thesample (55.0%) pre-sentedSVVdeviationresultswithinthestandardreference intheacutephaseofthedisease.SuchresultsofSVVwithin the limit considered normal was previously described in somepatientswithBPPV,11,23,26 suggestingthattheotolith
dysfunctionof BPPVwould notbevery extensivein these cases.11,26
In this study, most patients (77.8%) with abnormal absolute deviations of SVV before repositioning maneu-ver presented results withinthe referencestandard after therapeutic maneuver. The reduction in SVV deviations after the repositioning maneuver in BPPV was also pre-viously described.23,27 The two cases that continued to
showabnormaldeviationsofSVVperhapshadmore exten-sive otolith involvement,23 stenosis or obstruction of the
semicircularcanal,31 orthemaneuverfailedtoremoveall
particles,32possiblyrequiringtherepetitionofrepositioning
procedure33 or multipletreatments,34,35 for theresolution
of BPPV. A greater number of maneuvers could provide greater clearance of the otolithsin the affected semicir-cularcanal.33 Thedeviation ofSVV inBPPVappearstobe
relatedtothedysfunctionoftheotolithorgans;the elimina-tionofsemicircularcanalotolithswouldrestorethemacular structureandsideeffectsintheutricle.5,23
InthecasesofBPPVevaluatedinthisstudy,the signifi-cantreductionoftheaverageabsoluteSVVvaluesafterthe repositioning maneuver suggests an immediate favorable effectofthetherapeuticprocedureperformed,consistent withthepropositionthatthemodificationoftheSVVafter the therapeutic maneuver would reflect the migrationof otolithsbacktotheutricle.23
This research showed that the bucket method was
effectivetoevaluateSVV beforeandafterthe reposition-ing maneuver in BPPV patients. The significant reduction of the values of SVV deviations after the repositioning maneuver implies the utility of the bucket method to assessthefavorableeffectofthistherapeuticprocedurein BPPV.
Conclusion
Evaluations using the bucket test reveal that there is a reduction of the deviations of the subjective vertical visualimmediatelyafterparticlerepositioningmaneuverin patientswithbenignparoxysmalpositionalvertigo.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
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