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Effectiveness and repeatability of eye-tracking-based test in strabismus measurement of children
Leilei Zou1,2,3,4, Tian Tian1,2,3, Tamara Wygnanski-Jaffe5,6
1Department of Ophthalmology, Eye and ENT Hospital of Fudan University, Shanghai, China.
Insights
The eye-tracking-based test (ETBT) effectively measures eye deviation in children with strabismus, showing higher repeatability than the manual prism alternating cover test (PACT). This new method is reliable for young children.
Area of Science:
- Ophthalmology
- Pediatric ophthalmology
- Vision science
Background:
- Strabismus is a common condition in children.
- Accurate measurement of eye deviation is crucial for diagnosis and management.
- Current methods like the manual prism alternating cover test (PACT) have limitations.
Purpose of the Study:
- To evaluate the effectiveness of an eye-tracking-based test (ETBT) for measuring eye deviation angle in children.
- To compare the ETBT with the PACT in terms of accuracy and repeatability.
- To determine the minimum age at which ETBT can be reliably used.
Main Methods:
- A prospective, masked, cross-sectional study involving 95 children aged 1.8 years and older.
- Eye deviation was measured twice using both ETBT and PACT with habitual optical correction.
- Examiners compared PACT results with ETBT measurements.
Main Results:
- High correlation (approx. 90%) was found between ETBT and PACT measurements.
- ETBT demonstrated superior repeatability (correlation coefficient 0.99) compared to PACT (0.91).
- PACT results showed poor correlation between examiners for deviations >40 prism diopters.
Conclusions:
- The eye-tracking-based test (ETBT) is effective for measuring eye deviation in children as young as 1.8 years.
- ETBT offers higher repeatability than PACT for strabismus assessment.
- ETBT is a promising tool for objective and reliable eye deviation measurement in pediatric populations.
Objectives:
To assess the effectiveness of an eye-tracking-based test (ETBT) to measure eye deviation angle vs. a manual prism alternating cover test (PACT) in children with strabismus.
Design:
The prospective, masked, cross-sectional study included 95 children aged 1.8 years and older. Eye deviation was tested twice by each of ETBT and PACT. Each subject underwent four strabismus measurements, two by the ETBT and two by PACT. In each test, subjects were fixated on accommodative targets at 50 cm, with habitual optical correction allowed. Masked examiners compared the manual PACT results with those of the ETBT.
Results:
There was a high correlation (about 90%) between the ETBT and PACT. Repeatability of ETBT was higher than that of PACT (correlation coefficients of 0.99 and 0.91 respectively, p < .002). Age, strabismus type, and eye deviation measurement did not affect repeatability of ETBT. However, in PACT, results could not be correlated between the two examiners when the deviation was larger than 40 prism diopters.
Conclusions:
The ETBT was effective in measuring eye deviation in children as young as 1.8 years. The ETBT showed higher repeatability compared to PACT.
