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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
