RESEARCH ON BINOCULAR VISION CHARACTERISTICS IN PATIENTS WITH STRABISMUS
Main Article Content
Abstract
Objective: To evaluate binocular visual function characteristics in patients with strabismus.
Subjects and methods: A cross-sectional descriptive study was conducted on 38 patients aged ≥ 5 years with strabismus at the National Eye Hospital and Hanoi Medical University Hospital from September 2025 to April 2026. Patients underwent examinations including visual acuity using the Snellen chart, ocular motility assessment, Hirschberg test, cover-uncover test, prism measurement of deviation, accommodative convergence/accommodation ratio, near point of convergence, positive and negative fusional vergence, amplitude of accommodation, negative and positive relative accommodation, and Worth 4-dot test. Data were analyzed using SPSS 20.0 software.
Results: Exotropia accounted for 73.7% of cases, followed by esotropia, with no cases of vertical deviation. Positive fusional vergence was increased, while negative fusional vergence was markedly reduced. Amplitude of accommodation was below age-expected norms in 77% of eyes. Negative relative accommodation was increased in 90.5% of patients, whereas positive relative accommodation showed variability. Near point of convergence indicated reduced convergence function.
Conclusion: Patients with strabismus exhibit accommodative-vergence imbalance, characterized by convergence predominance and reduced divergence. A comprehensive treatment approach is required.
Article Details
Keywords
Strabismus, binocular vision, accommodation, convergence.
References
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