Classification of Concomitant Deviations

1. Classification of Concomitant Deviations Created on behalf of NHS NES as supplement to workshops on binocular vision and additional techniques.

2. Classification • Eso / exo / hyper/ hypo • Constant / intermittent / latent • Accommodative element • Other near / distance difference

3. ManifestEsotropia

4. ESOTROPIA Primary Constant Accommodative Element (larger Near) • Hypermetropic • Always manifest • Angle smaller with glasses • Angle smaller in distance • Onset 6m – 3yrs

5. ESOTROPIA Primary Constant Non-Accommodative • Hypermetropia does not affect angle • Always manifest • <10∆ difference Nr /Dist • Onset often early but vague

6. ESOTROPIA Primary Constant Non-Accommodative • Onset before 6/12 • Large constant angle • Often alternate • Associated with DVD and latent nystagmus Infantile

7. ESOTROPIA Intermittent Accommodative Fully accommodative • Hypermetropic +2.0 / +4.5 • Large manifest angle on accommodation without glasses • Fully controlled esophoria with glasses • Normal BSV (or microtropia) with glasses • Onset 18m – 4yrs

8. ESOTROPIA Intermittent • Low hypermetropia +1.0 / +3.0 • Large manifest angle near & distance without glasses • Manifest esotropia with glasses for near • Fully controlled esophoria in distance with glasses • Normal BSV (or microtropia) with glasses • Onset 4-5 Accommodative Convergence Excess

9. ESOTROPIA Intermittent Non-accommodative (rare) • Manifest esotropia near • BSV Distance • Not affected by plus lenses • Manifest in distance only • Lateral rectus weakness or post-op • Alternate day squint Near Esotropia Distance Esotropia Cyclic Esotropia

10. Secondary • Due to severe loss or impairment of vision • Esotropia - infancy onset • Exotropia – onset after early childhood • Divergence with time in amblyopia or absence of BV • Eso when previously exo or vice versa • Post-operative Divergence with time in amblyopia or absence of BV • Divergence with time Consecutive

11. Manifest Exotropia

12. Primary EXOTROPIA Constant Early onset • Rare • Suspect low VA • Often diagnosed from history / photographs • BSV may be recoverable Decompensated intermittent

13. Primary EXOTROPIA Intermittent • Often decompensated from exophoria • Manifest Near , controlled distance • Older children /adults • Check for dyslexia / stress • Angle similar near /distance • May be worse near or distance but angle similar Near exotropia Non-specific

14. Primary EXOTROPIA Intermittent Distance exotropia • Manifest exotropia 6m or Far Distance • Exophoria with normal BSV Near • <10∆ change with +/- 3.00 or after 30 mins occlusion True

15. Primary EXOTROPIA Intermittent • Clinically similar to true distance exotropia • Manifest distance, controlled near • Angle increases at 1/3m after 30 mins occlusion • After occlusion angle inceases at 1/3m with +3.00 lenses Distance exotropia Simulated Controlled with fusion Controlled with Accommodation

16. Heterophoria

17. Main difference between intermittent heterotropia and heterophoria is • Size of angle • Fusion range • Not cause