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Updated: Aug 11, 2026
07:04
A Step Beyond BRET: Fluorescence by Unbound Excitation from Luminescence (FUEL)
Published on: May 23, 2014
18th annual Frank Costenbader Lecture. Fusion and suppression: development and loss
1Department of Ophthalmology, University of British Columbia, Vancouver, Canada.
Journal of Pediatric Ophthalmology and Strabismus
|January 1, 1992
Summary
Congenital esotropia patients rarely achieve central fusion, even with early alignment. A congenital deficit in fusion potential is suggested, with potential midbrain lesions impacting fusion development.
Area of Science:
- Ophthalmology
- Neuroscience
- Pediatric Medicine
Background:
- Congenital esotropia is a common condition requiring early intervention.
- The potential for developing sensory fusion in these patients is not fully understood.
Purpose of the Study:
- To investigate the long-term sensory outcomes in patients with congenital esotropia treated early.
- To identify factors influencing the development of fusion and stereopsis.
Main Methods:
- Retrospective study of 118 patients with congenital esotropia.
- Patients underwent surgical and/or optical alignment before age 2, maintaining alignment for at least one year.
- Standardized examinations were performed after age 6 with a minimum 5-year follow-up.
Main Results:
- None of the patients achieved central fusion.
- 53% (53/118) achieved peripheral fusion with adequate fusional amplitude.
- 28% of those with peripheral fusion also had stereopsis.
- No specific factors were identified to explain the lack of fusion in 65 patients.
Conclusions:
- A congenital inability to develop fusion potential is postulated in congenital esotropia.
- The study suggests a potential midbrain lesion location for central fusion disruption.
- Fusion can be lost in adults due to sensory deprivation without suppression.
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