English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We present a comparison between measurements of the radius of the anterior and posterior lens surface, which was performed using corrected Scheimpflug imaging and Purkinje imaging in the same group of participants (46 for the anterior lens, and 34 for the posterior lens). Comparisons were also made as a function of accommodation (0 to 7 D) in a subset of 11 eyes. Data were captured and processed using laboratory prototypes and custom processing algorithms [for optical and geometrical distortion correction in the Scheimpflug system and using either equivalent mirror (EM) or merit function (MF) methods for Purkinje]. We found statistically significant differences in 4 of 46 eyes for the anterior lens radius, and 10 of 34 eyes for the posterior radius (using the MF and individual biometric data to process the Purkinje images). For the anterior lens, the agreement increases using individual biometry as opposed to biometric data from a model eye. For the posterior lens, the agreement increases using the MF as opposed to the EM method. For the changes during accommodation, no significant difference between the two techniques was found. In conclusion, the results of the cross-validation using the Scheimpflug and Purkinje imaging technique show that both techniques provide comparable lens radii and similar changes with accommodation. Purkinje tends to overestimate posterior lens radius, whereas pupil size limits the acquisition of posterior lens data with the Scheimpflug camera. Computer simulations using the Scheimpflug data as input show that the consistent slight overestimation of the posterior lens radius using Purkinje imaging can be partly attributed to the asphericity of the lens surface.

Crystalline lens radii of curvature from Purkinje and Scheimpflug imaging