Etiology of heterophoria and heterotropia

50 %
50 %
Information about Etiology of heterophoria and heterotropia

Published on June 16, 2016

Author: DrTukezbanHuseynova

Source: slideshare.net

1. Etiology of Heterophoria and Heterotropia Tukezban Huseynova, MD Specialist in Strabismus and Refractive Cornea, Briz-L Eye Clinic, Baku, Azerbaijan Tukezban@gmail.com

2.  Orthoforia occurs where both visual axes are directed towards the fixation point and do not deviate on dissociation.

3. Factors that determine the relative position of the visual axes.  Anatomical factors.  Innervational factors.

4. Factors Responsible for the Manifestation of a Deviation  Abnormalities of Fusion Mechanism  Reflexologic Theories

5. Heterophoria

6.  Where heterophoria is presented, both visual axes are directed towards the fixation point but deviate on dissociation.

7. Classification. • Esophoria - convergence excess - divergence weakness - non-specific • Exophoria - conveargence weakness - divergence excess - non-specific • Hyperphoria/hypophoria • Alternating hyperphoria/hypophoria • Cyclophoria

8. Aetiology. Esophoria • Anatomical – enophthalmos, narrow IPD, extraocular muscle anomalies • Refractive – suprable hypermetropia, anisometropia • High AC/A ratio • Weak negative fusional reserves

9. Aetiology. Exophoria • Anatomical – exophthalmos, wide IPD, extraocular muscle anomalies • Refractive – acquired myopia, presbyopia, anisometropia • Weak positive fusional reserves • Passage of time

10. Aetiology. Hyperphoria/hypophoria • Refractive – high myopia (heavy eye syndrome) • Weak vertical fusional reserves • Anatomical – displaced globes, abnormal extraocular muscles, ptosis

11. Heterotropia

12.  Heterotropia is a condition in which one or other visual axis is not directed towards the fixation point.

13. There are a number of different forms of heterotropia: • Esotropia • Exotropia • Hypertropia • Hypotropia • Cyclotropia • Dissociated vertical deviation (DVD) • Dissiciated horizontal deviation (DHD)

14. Factors Causing the Deviation.  Mechanical factors  Structural anomalies of extraocular muscles  Accommodation and refraction in comitant strabismus  Fixation disparity Previous eye surgeries or brain surgeries

15. Factors Causing the Deviation. Other Innervational (Neurologic) Factors in Comitant Strabismus.  Paretic elements  Anomalies of the brainstem  Anomalies of convergence and divergence  Vestibular system  Anomalies of the visual pathway  Brain damage  Embryopathy

16. Thank You

Add a comment