Electrodes for MfERG · HK Loop 15 € 1 +++ Estimation of Number of sizes Number of uses unit...

Jacques.charlier@metrovision.fr

ELECTRODESFOR

MULTIFOCAL ERG

WHAT IS NEEDED ?WHAT IS NEEDED ?

optical quality for «optical quality for « goodgood » retinal image» retinal imagerecord best possible signalrecord best possible signalfree from artifactfree from artifactshort setshort set--up timeup timecost effectivecost effective

CornealCorneal or non or non cornealcorneal electrodeelectrode??

MonopolarMonopolar or or bipolarbipolar electrodeelectrode??

BURRIAN ALLENBURRIAN ALLEN

ReferenceReference: : Burian & Allen EEG Clin Neur, 1954

GOLD LENSGOLD LENS

ReferenceReference: : Diagnosys, 2001

ERG JetERG Jet

ReferenceReference: : Grounauer, US patent, 1983

GOLD FOILGOLD FOIL

ReferenceReference: : Borda & al Doc Ophthalmol, 1978

DTL electrodeDTL electrode

ReferencesReferences: : Dawson & al., IOVS 1979Ram & al. Doc Ophthalmol 2003

HK LoopHK Loop

ReferencesReferences: : Hawlina & Konec, Doc Ophthalmol, 1992Hawlina, US patent, 1992

COMPARISONCOMPARISONsignal / noise ratiosignal / noise ratio

For the same quality of results

D = K x (S / N) 2

D = duration of examK = constantS = signalN = noise

If signal amplitude is reduced by 2examination duration increased by 22 = 4

COMPARISONCOMPARISONamplitude of signalamplitude of signal

204190

178

150

112

35

0

50

100

150

200

250

BA mon

opolar

ERG Jet

Gold fo

ilBA bi

polar

DTL fiber

Skin elec

trode

Am

plitu

de (µ

V)

COMPARISONCOMPARISONcost effectivenesscost effectiveness

++++++1115 €15 €HK HK LoopLoop

NumberNumber ofof usesusesNumberNumber ofof sizessizesEstimation Estimation ofofunit unit priceprice

typetype

25 €25 €

15 €15 €

15 €15 €

750 €750 €

500 €500 €

++++++11Gold FoilGold Foil

++11DTLDTL

++++11ERG JetERG Jet

++++++++33Gold Gold lenslens

++++++++77BurrianBurrian AllenAllen