Related Experiment Video
Updated: Nov 30, 2025
06:19
Comparison of Three Clinical Stereoscopic Methods for Measuring Binocular Visual Function During Amblyopic Treatment in Unilateral Amblyopia
Published on: September 27, 2024
417
Comparison between distance and near visual acuity in amblyopes.
Heejeong Chun1, Young Chun Lee
1Department of Ophthalmology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Kyungki-do, Republic of Korea.
Medicine
|November 12, 2020
Summary
Near visual acuity (NVA) is better than distant visual acuity (DVA) in amblyopia patients before treatment. NVA may underestimate amblyopia severity, impacting accurate diagnosis.
Area of Science:
- Ophthalmology
- Vision Science
- Pediatric Ophthalmology
Background:
- Amblyopia, or 'lazy eye,' affects vision development.
- Accurate diagnosis relies on visual acuity measurements.
- Distant visual acuity (DVA) is standard, but near visual acuity (NVA) is also assessed.
Purpose of the Study:
- To compare DVA and NVA in amblyopia patients.
- To determine if NVA can reliably diagnose amblyopia.
- To analyze factors influencing the difference between DVA and NVA.
Main Methods:
- Retrospective study of 73 amblyopia patients.
- NVA measured using a Snellen chart at 30 cm.
- DVA measured using a Dr Hahn vision test chart at 5 m.
Main Results:
- NVA was significantly better than DVA in amblyopes (P=.000).
- The difference between DVA and NVA was not significantly related to age, amblyopia type, spherical equivalent, or prism diopter.
- NVA may underestimate amblyopia severity.
Conclusions:
- NVA is better than DVA in untreated amblyopia.
- NVA's accuracy in diagnosing amblyopia may be limited.
- Consider NVA's potential to underestimate amblyopia severity.
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