Articles Vol. 67 No. 6 25/06/2026

RESEARCH ON BINOCULAR VISION CHARACTERISTICS IN PATIENTS WITH STRABISMUS

Nguyen Ngan Ha1,2,3,4, Nguyen Thu Trang2,4, Truong Thu Hue1,3, Tran Hai Dang1,3, Nguyen Thi Phuong Thuy1,3, Dao Thi Minh Thu1,3, Tran Thi Anh Tuyet1,3, Pham Viet Trinh1,3, Dang Thi Thao1,3, Do Ngoc Vinh1,3
1 Hanoi Medical University
2 National Eye Hospital
3 Trường Đại học Y Hà Nội
4 Bệnh viện Mắt Trung ương
DOI: 10.52163/yhc.v67i6.5503
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Keywords
Strabismus, binocular vision, accommodation, convergence.
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.

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