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Binocular Function in Subjects with Orthotropic Duane Retraction Syndrome
Bhagya Lakshmi Marella1,2, Ruby Moharana1, Ramesh Kekunnaya1
1a Child Sight Institute, Jasti V Ramanamma Children's Eye Care Center , L. V. Prasad Eye Institute , Hyderabad , India.
Journal of Binocular Vision and Ocular Motility
|April 30, 2019
Summary
Subjects with Duane Retraction Syndrome (DRS) exhibit normal accommodation but demonstrate impaired near point of convergence (NPC) and reduced fusional vergence reserves. Stereopsis is also significantly diminished in these patients.
Area of Science:
- Ophthalmology
- Neuroscience
- Vision Science
Background:
- Duane Retraction Syndrome (DRS) is a congenital eye movement disorder.
- Binocular vision function in DRS patients requires further investigation.
Purpose of the Study:
- To evaluate binocular vision parameters in subjects with orthotropic Duane Retraction Syndrome (DRS).
- To compare these parameters with age-matched normal controls.
Main Methods:
- Assessed near point of accommodation (NPA), near point of convergence (NPC), fusional vergence ranges (PFV and NFV), and stereopsis.
- Included 24 DRS subjects (14 Type 1, 2 Type 2, 8 Type 3) and 15 controls.
Main Results:
- Accommodative amplitude was normal in DRS subjects.
- NPC was significantly receded, and PFV/NFV reserves were reduced in DRS patients.
- Type 3 DRS showed poorer distance PFV/NFV reserves than Type 1 DRS; stereopsis was poor in all DRS subjects.
Conclusions:
- DRS patients have normal accommodation but impaired convergence and fusional vergence.
- Stereopsis deficits are common in individuals with DRS.
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