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Updated: Nov 7, 2025

Using an Automated Hirschberg Test App to Evaluate Ocular Alignment
Published on: March 24, 2020
[Prism-Induced Gaze Shift and Strabismus Treatment for Ocular Motility Disorders and Anomalous Head Posture]
Leila Sara Eppenberger1, Rahel DiTaranto1, Andrea Bücheler1
1Augenklinik, Kantonsspital St. Gallen, Schweiz.
Background:
The therapeutic treatment of ocular motility disorders and anomalous head postures (AHP) is often challenging. We report our experience with prism use in these patients.
Patients And Methods:
Retrospective case series of three patients with ocular motility disorders and associated AHP who were treated with prism correction.
Results:
A 37-year-old male with a traumatic left oculomotor nerve palsy suffered from a residual minor depression deficit and a severe elevation palsy. With OS: 10^ base-up he was corrected for left hypotropia only in down gaze. Ten yoked prisms base-up shifted the field of binocular single vision in primary position. A 45-year-old male with traumatic Parinaud syndrome and upward gaze palsy suffered from neck pain due to his pronounced chin elevation. He also had a right amaurosis with secondary exotropia. With OS: 8^ base-up, his AHP was corrected and his neck pain was alleviated. A 69-year-old woman with a left abducens nerve palsy adopted a left turn of 20° to compensate for her deviation in extreme right gaze. With OS: 20^ base-out, her AHP was corrected and she experienced no double vision in primary position.
Conclusions:
Prisms are used to correct strabismic deviations but also can successfully shift images towards another gaze in different clinical scenarios. Reduction of AHP, therefore, can be obtained by a prism-induced gaze shift in the direction of the motility restriction.
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