Introducing Dynamic Stimulation Aberrometry: Binocular Objective Accommodation versus Subjective Measures

Abstract

The objective measurement of binocular accommodation remains a challenge. The dynamic stimulation aberrometry (DSA) system uses wavefront measurements to dynamically assess accommodation. In this study, we sought to introduce this method in a large number of patients of varying age and compared it with the subjective push-up method as well as the historical results of Duane. This study is an evaluation of diagnostic technology. Ninety-one patients aged 20 to 67 years (70 healthy, phakic eyes and 21 myopic eyes after phakic intraocular lens implantation) were enrolled at a tertiary eye hospital. All patients underwent DSA measurements; the accommodative amplitude of 13 patients chosen at random was additionally examined using the subjective push-up method introduced by Duane. DSA measurements were also compared with Duane's historical results. Accommodative amplitude, dynamic parameters of accommodation, and near pupil motility. Dynamic stimulation aberrometry allowed objective measurement of binocular accommodation, which decreased with age (e.g., 30-39 years vs. > 50 years; 3.8 ± 0.9 diopters [D] and 0.1 ± 0.4 D, respectively). Dynamic parameters, such as time delay of the commencement of accommodation after near target presentation, increased with age (0.26 ± 0.14 seconds for 20-30 years vs. 0.43 ± 0.15 seconds for 40-50 years, P= 0.0002). The objective accommodative amplitude was significantly smaller than Duane's historic results (P= 0.001) as well as the subjective push-up method. Dynamic stimulation aberrometry records pupil motility dynamically in parallel to wavefront measurements. Maximum pupil motility during accommodation significantly decreased with age (P= 0.0002). Maximum pupillary speed did not correlate significantly with age. Dynamic stimulation aberrometry allows objective, dynamic, binocular measurement of accommodation and pupil motility with high time resolution in subjects with accommodative amplitudes up to 7 D. This article introduces themethod in a large study population and may serve as a control for further studies. Proprietary or commercial disclosure may be found after the references.