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Published on: October 18, 2024
871
Dioptric differences between clinically determined and metric-optimised refractions for adults with Down syndrome
Maureen D Plaumann1, Jason D Marsack1, Julia S Benoit1,2
1University of Houston College of Optometry, Houston, Texas, USA.
Summary
New wavefront-derived metrics improve refractive accuracy for individuals with Down syndrome, addressing limitations of standard clinical techniques. These methods account for higher-order aberrations and myopic errors, enhancing visual correction.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Standard clinical refraction techniques may fall short for individuals with Down syndrome.
- Wavefront aberrometry offers potential for more precise refractive error assessment.
Purpose of the Study:
- To compare dioptric differences between standard clinical refractions and two wavefront-derived metric-optimised methods (visual Strehl ratio [VSX] and pupil fraction tessellated [PFSt]).
- To investigate participant characteristics contributing to differences in refraction types.
Main Methods:
- Thirty adults with Down syndrome underwent three refractive corrections: VSX, PFSt, and clinical.
- Refractions were converted to vector notation (M, J0, J45) and analyzed using mixed-model repeated measures.
- Correlations examined relationships between dioptric differences and higher-order root mean square (RMS), spherical equivalent refractive error, and adaptive behavior scores.
Main Results:
- Significant differences were found between clinical refractions and both VSX (1.19 D) and PFSt (1.04 D) methods (p < 0.001).
- Increased dioptric differences correlated with higher-order RMS (R=0.64 for VSX vs. clinical) and myopic spherical equivalent refractive error (R=0.51 for PFSt vs. clinical).
Conclusions:
- Wavefront-optimised refractions (VSX, PFSt) provide different endpoints compared to standard clinical methods in individuals with Down syndrome.
- Higher-order aberrations and myopic refractive error contribute significantly to refractive uncertainty in this population.
- The choice of methodology, clinical techniques versus wavefront aberrometry, influences refractive outcomes.
Keywords:
Down syndromemetric-optimised refractionsobjective refractionvector analysiswavefront aberrationsMore Related Videos
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