Binocular Vision

Test Expected Values
Near Cover Test Ortho - 6XP
NPC 5/7cm Near
7/10cm Distance
Vergence Facility (3BI/12BO) 15 cycles/min
Positive Fusional Vergence 17/21/11
Negative Fusional Vergence 13/21/13
Positive Fusional Reserve
(Blur/Break/Recovery)
7-11 / 15-23 / 8-12 △
Negative Fusional Reserve
(Blur/Break/Recovery)
x / 5-9 / 3-5 △
Amplitude of Accomodation Minimum: 15 - (1/4)Age
Lag of Accomodation +0.25 to +0.75
Positive Relative Accomodation -2.37 (+/-1.00)
Negative Relative Accomodation +2.00 (+/-0.50)
ACA 4/1 △
Condition Cover Test NPC Vergence
Facility
Vergence
Amplitude
Accomodative
Amplitude
Binocular
Acc. Facility
Monocular
Acc. Facility
NRA/PRA MEM
Basic Exophoria Exo, D=N Normal Low BO @ D&N Low BO @ D&N Normal Fails (+) Normal Low NRA Low
Basic Esophoria Eso, D=N Normal Low BI @ D&N Low BI @ D&N Normal Fails (-) Normal Low PRA High
Convergence Insufficiency Exo, >N Receded Low BO Low BO Normal Fails (+) Normal Low NRA Low
Convergence Excess Eso, >N Normal Low BI Normal Normal Fails (-) Normal Low PRA High
Divergence Insufficiency Eso, >D Normal Low BI @ D Normal Normal Normal Normal Normal Normal
Divergence Excess Exo, >D Normal Low BO @ D Low BO @ D Normal Normal Normal Normal Normal
Accomodative Insufficiency No Pattern Normal Normal Normal Low Fails (-) Fails (-) Low PRA High
Fusional Vergence Dysfunction Low Eso or Exo Normal Low BI & BO Normal Normal Fails (+) & (-) Normal Low NRA/PRA Normal

Expected Refractive Error

VA Absolute Myopia/Hyperopia (D) Uncorrected Astigmatism (D)
20/20 0.00 Small
20/30 0.50 1.00
20/40 0.75 1.50
20/60 1.00 2.00
20/80 1.50 3.00
20/120 2.00 4.00
20/200 2.00 - 3.00 High

Significant Refractive Error

Isoametropic Anisometropic
Astigmatism ≥ 2.50D ≥ 1.50D
Myopia ≥ 6.00D ≥ 3.00D
Hyperopia ≥ 4.00D ≥ 1.00D

Lens Materials

Material Abbe Value Refractive Index
Glass 58.6 1.503
CR-39 56.8 1.498
Trivex 44 1.532
High Index 1.74 33 1.740
Polycarbonate 30 1.586