WHICH METHOD OF CONTRAST SENSITIVITY TESTING IS MOST EFFECTIVE AND PRACTICAL 10% CONTRAST VS 25% CON

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WHICH METHOD OF CONTRAST SENSITIVITY
TESTING IS MOST EFFECTIVE AND PRACTICAL?
10 CONTRAST VS 25 CONTRAST
ASCRS
2007 LEE T. NORDAN, MD
SAN DIEGO, CA

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• GOALS OF CONTRAST SENSITIVITY TESTING
• TO DEMONSTRATE LEVEL OF FUNCTIONAL ACUITY
• TO DIFFERENTIATE THE QUALITY OF VISION
  PROVIDED BY VARIOUS TYPES OF CORRECTIVE SURGERY
  -8.00 D LASIK vs. IOL MONO-VISION
  vs PRESBYOPIC IOL CONTACT LENS VS
  KERATO-REFRACTIVE SURGERY

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• ASSUMPTIONS (MY OPINIONS)
• MUST TEST EACH EYE OF EVERY PATIENTIN ORDER TO
  KNOW FUNCTIONAL VISION
• DRIVING SIMULATION TESTS ARE RESEARCH PROJECTS
• SNELLEN-TYPE TESTING IS IMPORTANT
• 25 CONTRAST TARGETS ARE NOT SENSITIVE ENOUGH

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CONTRAST LUM BACKGROUND - LUM TARGET
LUM BACKGROUND LUM TARGET SNELLEN
CONTRAST 100 - 5 94

100 5 CONTRAST 100 - 60
40 25 100 60
160 CONTRAST 100 - 80 20 11
100 80 180
A
A
A
5
CONTRAST 50 - 5 45 80
50 5 55 CONTRAST 7 - 5 2
16 7 5 12 WOULD
A REDUCED BACKGROUND LUMINANCE BE MORE INDICATIVE
OF REAL-WORLD CONTRAST FUNCTION?(NIGHT-TIME
DRIVING)
A
A
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SNELLEN RESULTS WITH 10 CONTRAST
TESTING NORMS AGE DEPENDENT (LENS CLARITY)
WITH 20/20 SNELLEN AGE 20, 10
CONTRAST LOSS OF 1 LINE AGE 40,
10 CONTRAST LOSS OF 1.5 - 2 LINES RESULTS TO
BE PRESENTED USING 10 CONTRAST
MULTI-FOCAL IOL LASIK PRK
HARD CONTACT LENS SOFT CONTACT LENS
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CONCLUSIONS 25 CONTRAST - NOT SENSITIVE
ENOUGH 10 CONTRAST TESTING - BETTER ALLOWS
FOR GREATER DIFFERENTIATION SNELLEN
VISUAL ACUITY STYLE LOW LUMINANCE BACKGROUND
TESTING MORE PREDICTABLE? INDEPENDENT OF
PUPIL SIZE?
A
A