heterotropia

Last reviewed 03/2023

Heterotropia is an upward deviation of the non-fixing eye. The higher rather than the lower eye is designated. It is far less common than horizontal strabismus and usually, develops after childhood.

Congenital causes include anomalies in muscle attachments. Acquired causes include closed head trauma, orbital tumours, brain stem lesions, and systemic diseases such as multiple sclerosis, Grave's disease, and myasthenia gravis.

Clinical findings vary. Useful investigations are prism and cover measurements. Diplopia is usual if the heterotropia develops after the age of 6-8 years. Earlier onset is associated with sensory adaptations such as suppression and anomalous retinal correspondence in the direction of gaze in which there is strabismus. Changes in head posture are common and typically vary according to the direction of gaze. Non-concomitance is usual.

Heterotropia is most commonly due to superior oblique paresis.

A spectacle prism and/or the occlusion of one eye may be sufficient to correct minor and less non-concomitant deviations. Surgery is indicated if these are unsuccessful. Adjustable sutures are often used since great precision is usually necessary.