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Evaluation of binocular vision parameters as screening indicators for asthenopia
Guan-Cheng Lin1, Pei-Ru Huang1, Yueh-Jung Chen1
1Department of Optometry, Chung Hwa University of Medical Technology, Tainan, Taiwan.
Summary
This study suggests using positive relative accommodation (PRA) as an objective measure for screening asthenopia, offering high accuracy and potential for clinical use.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Asthenopia, or eye strain, is typically diagnosed using subjective questionnaires.
- Subjective methods can be limited by symptom specificity and individual response bias.
- Objective measures are needed to improve the accuracy and reliability of asthenopia screening.
Purpose of the Study:
- To evaluate the feasibility of using binocular vision parameters as objective indicators for asthenopia screening.
- To reduce the reliance on subjective questionnaires in diagnosing asthenopia.
- To identify specific binocular vision parameters with high screening efficacy.
Main Methods:
- 50 young adults underwent binocular vision tests, measuring parameters like negative relative accommodation (NRA), positive relative accommodation (PRA), near point of accommodation (NPA), near point of convergence (NPC), and binocular accommodative facility (BAF).
- Participants completed the Convergence Insufficiency Symptom Survey Questionnaire (CISS-Q) for post-hoc grouping into asthenopia and non-asthenopia groups.
- Receiver operating characteristic (ROC) curve analysis was used to assess the screening efficacy of different parameters.
Main Results:
- Significant differences in NRA, PRA, NPC, and BAF were observed between asthenopia and non-asthenopia groups (p < 0.001).
- PRA showed the highest screening efficacy with a cut point of -2.25 D, achieving 88.5% sensitivity and 91.7% specificity.
- NPC and NRA also demonstrated significant screening capabilities, with specific cut points, sensitivities, and specificities.
Conclusions:
- Positive relative accommodation (PRA) at -2.25 D is proposed as a highly sensitive and specific indicator for asthenopia screening.
- Binocular vision parameters, particularly PRA, offer a potential objective method for asthenopia assessment in clinical practice.
- Further validation of PRA as a screening tool could enhance routine optometric examinations without additional equipment.
