Hta Msac 1078 Mmop 20060719

Title:Multifocalmulti-channelobjectiveperimetry(MMOP)forthe diagnosisofvisualfielddefects,August2004

Agency:MedicalServicesAdvisoryCommittee(MSAC)

Australian GovernmentDepartmentof Health andAgeing

GPOBox 9848Canberra ACT2601Australia

Reference:MSACapplication1078,Assessmentreport,ISBN0642827311, ISSN1443-7120

Aim

Toassessthesafetyandeffectivenessof multifocalmulti-channelobjectiveperimetry(MMOP) comparedtostaticautomatedperimetryforthediagnosisof visualfielddefectsandunderwhat circumstancespublicfundingshouldbesupported.

Conclusionsandresults

SafetyTherewaslittlepublishedevidenceofthesafetyofMMOP.However,asthe testisnon-invasivetheriskstosubjectsshouldbeminimal.Scalpelectrodes usedforMMOPmaycauseskinirritationorminortraumaalthoughthe frequencyofsucheventsisunknown.

EffectivenessDuetothelimitationsoftheavailableevidenceitisunclearwhetherMMOPis

equivalenttostaticautomatedperimetryintermsofdiagnosticaccuracyin patientswithundiagnosedvisualfielddefects.Overallthediagnosticaccuracy ofMMOPcouldnotbeestablishedastherewerewidevariationsinthe reportedsensitivities(100-75%)andspecificities(97-45%).Sensitivitywas highlydependentontheMMOPthresholdsofpositivityused.Specificitywas usuallydependentonthepopulationused,forexample,specificitywashighest inthosestudiesusingnormalcontrolsandlowerinsubjectswithsuspected glaucoma.TheabilityofMMOPtodiagnosepeoplewithpre-perimetric disease(ie,ganglioncelldamagepriortothedevelopmentofvisualfieldloss) wasnotadequatelyaddressedinanyofthestudies.Inordertodeterminethe truepredictivevalueofMMOP,longitudinaldatawouldbenecessaryto determineifpatientsactuallydevelopeddisease.

Cost-effectivenessAstherewasinsufficientevidencetodemonstratethecomparative

effectivenessofMMOP,acosteffectivenessanalysiscouldnotbeundertaken. Ananalysisofcostbasedontheapplicant’smodeldidnotdemonstratecost savingsforMMOPcomparedtothecurrentalternativetechnology.

Recommendations

MSACdidnotrecommendpublicfundingformultifocalmultichannelobjectiveperimetryfor thediagnosisofvisualfielddefects.OveralltheMSACconcurredthatalthoughMMOP

appearedtobesafetherewasinsufficientevidencetodemonstrateits’effectivenesscomparedto otheralternativetechnologies.Asaresult,itscost-effectivenesscouldnotbedetermined.

Method

InNovember2002theMSACreviewedmultifocalmultichannelobjectiveperimetry(MSAC Reference13)recommendingthatsincetherewasinsufficientevidencepertainingtoMMOP, publicfundingshouldnotbesupportedfortheprocedure.Inresponsetoanapplicationfor fundingoftheMMOP,MSACupdatedthereviewoftheevidence,incorporatingunpublished datafromtheapplicant.MSACconductedasystematicreviewofmedicalliteraturepublished from2002to2004viaMedline,Medlineinprocessandothernon-indexedcitations,EMBASE, BiologicalAbstracts,CINAHLandtheCochraneLibrary.Internetsourcesandhealth technologyassessmentsiteswerealsosearched.Astherewasinsufficientevidencetoassessthe comparativecost-effectivenessofMMOP,acostanalysisbasedonthemodelpresentedinthe applicationtoMSACwasexaminedanddiscussed.