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Rigid Gas-Permeable Contact Lenses Fitting Philosophy for Unilateral Aphakic Infants
Xiaoxiao Zhang1, Junwen Zeng, Zhou Zhai
1State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Optometry department, Sun Yat-sen University, Guangzhou, China.
Insights
This study offers guidelines for fitting rigid gas-permeable (RGP) contact lenses in infants with unilateral aphakia, using age to determine initial lens parameters when precise measurements are unavailable.
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Contact Lens Technology
Background:
- Unilateral aphakia in infants presents unique challenges for contact lens fitting.
- Accurate initial contact lens parameters are crucial for visual development and ocular health.
- Establishing reliable fitting guidelines is essential for managing these complex cases.
Purpose of the Study:
- To develop age-based guidelines for selecting initial rigid gas-permeable (RGP) contact lens (CL) power, base curve (BC), and diameter for unilateral aphakic infants.
- To provide a practical approach for fitting CLs when precise biometry is difficult to obtain in infants.
- To correlate infant age with RGP CL parameters for initial fitting.
Main Methods:
- Retrospective analysis of 52 infants (52 eyes) fitted with RGP CLs for unilateral aphakia.
- Assessment of refractive status via retinoscopy and determination of initial CL parameters (BC, diameter) using keratometry and fluorescein patterns under sedation.
- Correlation and linear regression analyses to establish relationships between infant age and CL parameters.
Main Results:
- Mean initial RGP CL parameters were 25.46±4.83 D power, 7.57±0.40 mm BC, and 9.48±0.23 mm diameter.
- Significant correlations were found between infant age and CL power (r=-0.676), BC (r=0.367), and diameter (r=0.497).
- A regression model was developed: CL power = 31.66 - 0.62 × age. Lens adjustments occurred every 3-5 months. Mild conjunctivitis was the only adverse event.
Conclusions:
- Infant age is a reliable factor for determining initial RGP CL parameters in unilateral aphakia when precise biometry is unobtainable.
- The developed empirical fitting guidelines offer a practical solution for managing aphakic infants.
- RGP CLs demonstrated ideal fit characteristics and a favorable safety profile in this pediatric population.
Purpose:
To provide fitting guidelines with suggested powers and base curves (BCs) and diameters for initial rigid gas-permeable (RGP) contact lenses (CLs) selection for unilateral aphakic infants based on age.
Methods:
Records of 52 children (52 eyes) with RGP CLs to unilateral aphakia between 2014 and 2019 were evaluated. Refractive status was assessed by standard retinoscopy. The original BC and diameter were determined by keratometric readings and fluorescein pattern under sedation. Correlation analysis was performed between age and CLs parameters. Linear regression analysis was used to develop a model for estimating power with the help of infant's age. Subgroup analysis was performed by grouping the eyes into four groups according to age. Lens adjustments and adverse events were also evaluated.
Results:
The median age was 9.0 months (interquartile range [IQR], 5.25-13.0 months). The mean power and BC and diameter of the initial RGP CLs were 25.46±4.83 diopters, 7.57±0.40 mm, and 9.48±0.23 mm, respectively. All these parameters showed correlations with infant's age (Pearson r=-0.676, 0.367, and 0.497, respectively; P=0.000, 0.008, and 0.000, respectively). Regression analysis revealed that CL power =31.66 to 0.62×age (P<0.001). The median follow-up was 7.50 months (IQR, 3.0-11.0 months). Lens adjustments took about every 3 months before 1 year of age and every 5 months afterward (F=3.442; P=0.024). The RGP CLs provided ideal fit characteristics, and no severe lens-related adverse event occurred except only one patient had mild conjunctivitis.
Conclusions:
Our empirical RGP CLs fitting philosophy presented that aphakic infant's age can be used to determine the initial lens if accurate biometry cannot be obtained initially.
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