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An office-based fix-and-follow grading system assessing visual function in preverbal children
Hyeshin Jeon1,2, Jae Ho Jung3, Hee-Young Choi4,5
1Department of Ophthalmology, School of Medicine, Pusan National University, 1-10 Ami-dong Seo-gu, Busan, 49241, South Korea.
Insights
A new grading system for assessing infant visual function using the Fix-and-Follow method was developed. This reliable and reproducible scale is easy to use in clinical settings for preverbal children.
Area of Science:
- Ophthalmology
- Pediatric Vision Assessment
Background:
- Assessing visual function in infants presents challenges.
- The Fix-and-Follow method is commonly used but lacks a standardized grading system.
- A reproducible method is needed to evaluate visual development in preverbal children.
Purpose of the Study:
- To develop and validate a novel grading system for the Fix-and-Follow method.
- To assess visual function development in preverbal children.
- To establish a reproducible and reliable tool for clinical use.
Main Methods:
- A cross-sectional study evaluated the new grading system in 21 preverbal children.
- Fixation was graded based on response duration and ability to shift gaze.
- Following was assessed by smooth pursuit eye movements.
- Two ophthalmologists independently applied the grading system, with repeat testing for intra-observer agreement.
Main Results:
- The grading system demonstrated excellent intra-observer agreement (Kappa = 0.823) and good inter-observer agreement (Kappa = 0.625).
- Discrepancies in scores were noted in patients with abnormal ocular movements.
- The system proved effective in differentiating visual function capacities.
Conclusions:
- The developed Fix-and-Follow grading scale is easily applicable in pediatric office settings.
- The scale is reliable and reproducible for assessing visual function in preverbal children.
- This tool enhances the objective evaluation of early visual development.
Background:
Assessing visual function in infants is usually challenging. Fix-and-Follow is a simple and popular method for assessing early development of visual perception in infants, currently however, there is no formal reproducible method for grading the capacity of fix-and-follow. This study was to develop and validate a new fix-and-follow grading system for assessing visual function development in preverbal children.
Methods:
In this cross-sectional study, the fix-and-follow grades was evaluated in 21 consecutive preverbal children. Fixation was categorised as grade 1 if there was no response to the target and grade 2 if there was a response but only for < 3 s. Grades of 3 and 4 were assigned based capacities to (1) fix on a moving target for ≥3 s, and (2) shift fixation from one target to another. If only one of these two criteria was met, grade 3 was assigned. If both were met, grade 4 was assigned. Following was evaluated using smooth pursuit movement, where grade 1 indicated no movement, grade 2 partial movement, and grade 3 complete movement. Two ophthalmologists independently applied the grading method in all patients. Then one of two examiners repeated the examinations to investigate the intra-observer agreement of the grading system.
Results:
Intra-observer agreement was excellent (Kappa coefficient = 0.823) and inter-observer agreement was good (Kappa coefficient = 0.625). All patients who exhibited abnormal ocular movement had score discrepancy between a new fix-and-following grading examination.
Conclusions:
The new fix-and-follow grading scale can be applied easily in preverbal children in an office setting, and it proved reliable and reproducible.
