Accommodation in phakic and pseudophakic eyes measured with subjective and objective methods

Abstract

PURPOSE:To measure accommodation subjectively and objectively and assess anterior segment changes during accommodation in phakic eyes and pseudophakic eyes. METHODS: Subjective and objective accommodation measurements and pupillometry were performed in phakic and pseudophakic patients. Refraction and pupil diameter were recorded with different accommodation stimuli. Corneal higher-order aberrations (HOAs) and anterior chamber depths (ACDs) were detected with a rotating Scheimpflug camera. RESULTS:The mean age of the 44 patients in the phakic group was 36.34 years G 16.6 (SD) and of the 27 patients in the pseudophakic group, 69.3 G 9.98 years. The mean subjective accommodation was 4.49 G 3.48 diopters (D) in phakic eyes and showed significant correlation with age, spherical aberration, changes in pupil diameter, and ACD. The mean subjective accommodation was 0.50 G 0.28 D in pseudophakic eyes. In phakic eyes, the mean objective accommodation was 0.46 G 1.02 D, 1.06 G 1.33 D, and 2.2 G 1.9 D with 2.0 D, 3.0 D, and 5.0 D, respectively, of stimulus. In pseudophakic eyes, measurable objective accommodation was recorded. In phakic eyes, the correlations were significant between these values and age, changes in ACD, pupil size, and corneal spherical aberration. In pseudophakic eyes, the only correlation was with the spherical equivalent value.

Comparing Autorefractors for Measurement of Accommodation

“…The Grand Seiko WAM-5500 is now a reference instrument in the study of accommodation. [24][25][26] The main goal of this study is to compare the static and dynamic accommodative measurements obtained with the PowerRef-II and the Grand Seiko WAM-5500. These instruments are two of the most widely used in research to assess the accommodative response.…”

Developments in the correction of presbyopia II: surgical approaches

“…However, although there is some evidence that such effects may occur (see, e.g. Patel et al ., for review), the results of different studies are contradictory and it is doubtful whether movement of conventional single‐vision IOLs contributes any significant systematic power change to the eye …”

A Comparative Study of Two Different Accommodative Intraocular Lenses: The Visual and Accommodative Amplitude Outcomes

“…Under standard room illumination, the patient was seated with a full distance refractive correction while viewing the smallest letter on the visual acuity chart. Then, minus-power lenses were gradually increased in 0.25 D steps until the visual target was blurred (minus-lenses-to-blur-method), and the added diopter was defined as the amplitude of accommodation (12). Anterior chamber depth was measured objectively with Sirius Scheimpflug-Placido topographer (Costruzione Strumenti Oftalmici, Florence, Italy) (4,12).…”

“…Then, minus-power lenses were gradually increased in 0.25 D steps until the visual target was blurred (minus-lenses-to-blur-method), and the added diopter was defined as the amplitude of accommodation (12). Anterior chamber depth was measured objectively with Sirius Scheimpflug-Placido topographer (Costruzione Strumenti Oftalmici, Florence, Italy) (4,12). The distance between the anterior surface of the IOL and the corneal vertex was referred to as the anterior chamber depth and measured before and after pilocarpine instillation.…”