-Reference-
Vision
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 - (¼)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 |