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Published on: March 3, 2023
Repeatability of topographic and aberrometric measurements at different accommodative states using a combined
Claudia Gabriel1, Oliver Klaus Klaproth1, Christine Titke1
1From the Department of Ophthalmology, Goethe-University, Frankfurt, Germany.
Purpose:
To evaluate the repeatability of corneal first-surface aberrations and aberrometric measurements of a combined aberrometer-topographer (iTrace Visual Function Analyzer) for 5 accommodative stimuli.
Setting:
Department of Ophthalmology, Goethe-University, Frankfurt, Germany.
Design:
Prospective case series.
Methods:
Eyes of young adults with low to moderate myopia or hyperopia were examined in 2 measurement series comprising 3 corneal topography measurements and wavefront measurements focusing on targets at 5 distances (0.4, 0.5, 0.6, 1.0, and 4.0 m). Repeatability was analyzed using the standard deviation (SD) within 6 measurements and the coefficient of repeatability (CoR) by Bland-Altman analysis of the means of the 2 measurement series.
Results:
Fifty eyes (50 subjects) were evaluated. The lowest calculated mean SD/CoR measurements using the aberrometer function at 5 target distances were 0.07 μm/0.14 μm for total ocular aberrations root mean square (RMS), 0.07 μm/0.16 μm for lower-order aberrations (LOAs) RMS, 0.03 μm/0.66 μm for higher-order aberrations (HOAs) RMS, 0.10 diopter (D)/0.22 D for sphere, 0.08 D/0.13 D for cylinder, and 0.09 D/0.21 D for the spherical equivalent (SE). Repeatability of the total RMS, LOAs RMS, sphere, and SE measurements improved with increasing target distance (P < .01 for aberrometric values; P < .03 for refractive values). Measurement reproducibility using the corneal topographer showed mean SDs/CoRs of 0.19 μm/0.41 μm for total RMS, 0.19 μm/0.39 μm for LOAs RMS, and 0.08 μm/0.23 μm for HOAs RMS.
Conclusion:
The aberrometer showed satisfactory results for measurement repeatability at all target distances and declining repeatability with increasing accommodation effort.
Financial Disclosure:
No author has a financial or proprietary interest in any material or method mentioned.
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