Table 1.
Clinical signs used in the study for diagnosing accommodative and binocular anomalies (AA: accommodative amplitude; MAF/BAF: monocular/binocular accommodative facility; MEM: monocular estimate method; PRA/NRA: positive/negative relative accommodation; PFV/NFV: positive/negative fusional vergence; NPC: near point of convergence; VF: vergence facility; Δ: prism diopters; D: diopters; cpm: cycles per minute; BO: base-out; BI: base-in).
| Dysfunction | Fundamental sign | Complementary sign |
|---|---|---|
| Accommodative dysfunctions | ||
| Accommodative insufficiency | Reduced AA: 2.00 D < minimum AA (15–0.25 × age) | MAF < 6 cpm with −2.00 D lenses |
| BAF < 3 cpm with −2.00 D lenses | ||
| MEM > 0.75 D | ||
| PRA < 1.25 D | ||
| Accommodative excess | MAF < 6 cpm with +2.00 D lenses | PRA ≥ 3.50 D |
| BAF < 6 cpm with +2.00 D lenses | ||
| MEM < 0.25 D | ||
| NRA < 1.50 D | ||
| Accommodative infacility | MAF < 6 cpm with ±2.00 D lenses | BAF < 3 cpm with ±2.00 D lenses |
| PRA < 1.25 D | ||
| NRA < 1.50 D | ||
|
| ||
| Binocular dysfunctions | ||
| Convergence insufficiency | Significant exophoria at near vision (≥6 Δ), greater than far vision | PFV at near ≤ 11/14/3 Δ |
| NPC ≥ 6 cm | ||
| VF < 13,4 cpm with 12 Δ base-out prism | ||
| BAF < 3 cpm with +2.00 D lenses | ||
| MEM < 0.25 D | ||
| NRA < 1.50 D | ||
| Convergence excess | Significant esophoria at near vision (≥1 Δ), greater than far vision | NFV at near ≤ 8/16/7 Δ |
| VF < 13.4 cpm with 3 Δ base-in prism | ||
| BAF < 3 cpm with −2.00 D lenses | ||
| MEM > 0.75 D | ||
| PRA < 1.25 D | ||
| Divergence excess | Significant exophoria at far vision (≥4 Δ), greater than near vision (the difference must be >5 Δ) | PFV at far ≤ 4/10/5 Δ |
| PFV at near ≤ 11/14/3 Δ | ||
| NPC ≥ 6 cm | ||
| VF < 13,4 cpm with 12 Δ base-out prism | ||
| BAF < 3 cpm with +2.00 D lenses | ||
| MEM < 0.25 D | ||
| NRA < 1.50 D | ||
| Basic esophoria | Significant esophoria at far and near vision of equal amount (deviations within 5 Δ of one another are considered equal) | NFV at far ≤ X/3/1 Δ and at near ≤ 8/16/7 Δ |
| VF < 13.4 cpm with 3 Δ base-in prism | ||
| BAF < 3 cpm with −2.00 D lenses | ||
| MEM > 0.75 D | ||
| PRA < 1.25 D | ||
| Basic exophoria | Significant exophoria at far and near vision of equal amount (deviations within 5 Δ of one another are considered equal) | PFV at far ≤ 4/10/5 Δ and at near ≤ 11/14/3 Δ |
| NPC ≥ 6 cm | ||
| VF < 13,4 cpm with 12 Δ base-out prism | ||
| BAF < 3 cpm with +2.00 D lenses | ||
| MEM < 0.25 D | ||
| NRA < 1.50 D | ||
| Fusional vergence dysfunction | PFV and NFV reduced at far and near vision or VF < 13.4 cpm with both prisms of the combination used of 12 BO/3 BI | BAF < 3 cpm with ±2.00 D lenses |
| PRA < 1.25 D and NRA < 1.50 D | ||