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Quantitatively comparing weekly changes in retinal vascular characteristics of eyes eventually treated versus not
Gloria J Hong1, Jagger C Koerner1, Marguerite C Weinert2
1Department of Ophthalmology, Duke University, Durham, North Carolina.
Insights
Quantitative analysis of retinal vascular features using ROPtool can predict the need for retinopathy of prematurity (ROP) treatment as early as 32 weeks postmenstrual age. ROPtool index values are more predictive than index changes.
Area of Science:
- Ophthalmology
- Neonatology
- Medical Imaging Analysis
Background:
- Retinopathy of prematurity (ROP) is a leading cause of childhood blindness.
- Early detection and intervention are crucial for managing ROP.
- Quantitative analysis of retinal vasculature may offer predictive insights.
Purpose of the Study:
- To quantitatively compare retinal vascular characteristics over time in eyes treated versus not treated for ROP.
- To assess the predictive value of ROPtool indices for ROP treatment necessity.
Main Methods:
- Longitudinal study of narrow-field retinal images from infants screened for ROP.
- Analysis using ROPtool, quantifying tortuosity index (TI), dilation index (DI), sum of adjusted indices (SAI), and tortuosity-weighted plus (TWP).
- Comparison of ROPtool indices and their weekly changes between treated and untreated eyes.
Main Results:
- ROPtool indices differed significantly between treated and untreated eyes at various postmenstrual ages (PMA).
- Differences were observed for TI, SAI, and TWP at PMA 33-35 and 37 weeks, and for DI at PMA 33-34 and 37 weeks.
- Weekly change in SAI differed between groups at 32 weeks PMA.
Conclusions:
- Quantitative retinal vascular analysis with ROPtool can predict the need for ROP treatment by 32 weeks PMA.
- ROPtool index values are more effective predictors than their rate of change.
Purpose:
To quantitatively compare retinal vascular characteristics over time in eyes eventually treated versus not treated for retinopathy of prematurity (ROP), using ROPtool analysis of narrow-field retinal images.
Methods:
This longitudinal study used prospectively collected narrow-field retinal images of infants screened for ROP, prior to treatment, if needed. Images were analyzed using a methodology that combines quadrant-level measures from several images of the same eye. For the longitudinal analysis, one examination per postmenstrual age (PMA) was included per eye. We compared the following ROPtool indices and their change per week between eyes eventually treated versus not treated for ROP: tortuosity index (TI), dilation index (DI), sum of adjusted indices (SAI), and tortuosity-weighted plus (TWP). Analysis was performed on three levels: eye (mean value/eye), quadrant (highest quadrant value/eye), and blood vessel (highest blood vessel value/eye).
Results:
Of 832 examinations (99 infants), 745 images (89.5%) had 3-4 quadrants analyzable by ROPtool. On the eye level, ROPtool indices differed between eyes eventually treated versus not treated at PMA of 33-35 and 37 weeks for TI, SAI, and TWP, and at PMA of 33-34 and 37 weeks for DI (P ≤ 0.0014), and change per week differed between eyes eventually treated versus not treated only for SAI at PMA of 32 weeks (P < 0.001).
Conclusions:
Quantitative analysis of retinal vascular characteristics using ROPtool can help predict eventual need for treatment for ROP as early as 32 weeks PMA. ROPtool index values were more useful than change in these indices to predict eyes that would eventually need treatment for ROP.
