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Using an Automated Hirschberg Test App to Evaluate Ocular Alignment
05:40

Using an Automated Hirschberg Test App to Evaluate Ocular Alignment

Published on: March 24, 2020

Alternate day exotropia.

Emma Dawson1, Gill Adams, Lak Mengher

  • 1Moorfields Eye Hospital, London, UK. Emma.Dawson@moorfields.nhs.uk

Strabismus
|December 17, 2009
PubMed
Summary
This summary is machine-generated.

Cyclic exotropia, a rare condition, alternates between manifest strabismus and controlled heterophoria. This report details two pediatric cases, offering insights into this unusual eye alignment disorder.

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Area of Science:

  • Ophthalmology
  • Pediatric Ophthalmology
  • Strabismus Research

Background:

  • Cyclic strabismus is a rare condition characterized by alternating manifest strabismus and controlled heterophoria over a regular pattern, typically 48 hours.
  • During the 'straight' phase, patients exhibit controlled heterophoria with good fusion and stereopsis.
  • During the 'squinting' phase, patients present with constant manifest strabismus, lacking fusion and stereopsis.

Observation:

  • This study presents two cases of alternate-day exotropia in young, non-Japanese female children.
  • One patient required strabismus surgery for persistent binocularity.
  • The second patient developed alternate-day exotropia post-surgery for intermittent exotropia, eventually resolving spontaneously.

Findings:

  • These are the first reported cases of cyclic exotropia in non-Japanese female children.
  • The cases presented without any ocular or systemic pathologies.
  • The condition demonstrated variability in presentation and resolution, with one case requiring surgical intervention and the other resolving over time.

Implications:

  • Highlights the presentation of cyclic exotropia in diverse pediatric populations.
  • Suggests potential for spontaneous resolution in some cases of cyclic exotropia.
  • Informs diagnostic and management strategies for this rare strabismus variant.