Full 3-D OCT-based pseudophakic custom computer eye model

Abstract

We compared measured wave aberrations in pseudophakic eyes implanted with aspheric intraocular lenses (IOLs) with simulated aberrations from numerical ray tracing on customized computer eye models, built using quantitative 3-D OCT-based patient-specific ocular geometry. Experimental and simulated aberrations show high correlation (R = 0.93; p<0.0001) and similarity (RMS for high order aberrations discrepancies within 23.58%). This study shows that full OCT-based pseudophakic custom computer eye models allow understanding the relative contribution of optical geometrical and surgically-related factors to image quality, and are an excellent tool for characterizing and improving cataract surgery.

Keywords: (110.4500) Optical coherence tomography; (200.4560) Optical data processing; (220.1010) Aberrations (global); (330.7326) Visual optics, modeling.

Fig. 1

Acquisition at two different foci (cornea and lens) (a) Vertical cross-sectional scans of a patient’s cornea while fixating foveally, i.e. along the line of sight; (b) Vertical cross-sectional scans of a patient’s cornea, while fixating eccentrically, i.e. pupilary axis aligned with the OCT optical axis (c) Vertical cross-sectional scans of the IOL implanted in patient. Typical image acquisitions are obtained with the alignment as in (b) and (c). The yellow line indicates the iris plane, used for merging. Images are for subject S1#OD.

Fig. 2

Illustration of the computation of aberrations using quantitative OCT geometrical data in a customized computer pseudophakic eye model.

Fig. 3

Anterior and posterior corneal topographic maps from Pentacam (upper panel) and OCT (lower panel). OCT-based maps were used in the computer eye models. Data are for 6-mm pupil.

Fig. 4

Measured (LRT, 1st column) and Simulated (from OCT-based geometry/biometry, 2nd −5th columns) wave aberration maps in three pseudophakic Simulated aberrations include wave aberration maps for the anterior cornea alone (2nd column); anterior and posterior cornea (3rd column); eye wave aberration with IOL assuming no tilt and decentration (4th column); eye wave aberration with IOL with no tilt/decentration (5th column). (a) Wave aberration maps including astigmatism (no tilt or defocus); (b) Wave aberrations for 3rd and higher order; Data are for 5-mm pupil, and for foveal fixation, i.e. including eye rotation.

Fig. 5

(a) RMS Astigmatism; (b) RMS Spherical Aberration; (c) RMS Trefoil; (d) RMS Coma; (e) RMS Tetrafoil, for anterior corneal RMS (blue bars), total corneal RMS (red bars), simulated total eye RMS assuming centered IOL (green bars), simulated total eye RMS assuming real IOL tilt/decentration (purple bars); and experimental (LRT) total eye aberration (light blue bars).

Fig. 6

Linear correlations between measured and simulated Zernike coefficients (astigmatism and 3rd and higher orders) in (a) S#1 OD; (b) S#2 OS; (c) S#3 OS; (d) combining data from the three subjects (72 points). Data are for 5-mm pupil diameters.

Fig. 7

(a) MTFs (radial profiles) for astigmatism and higher odder terms (b) MTFs (radial profiles) for 3rd and higher order aberrations, for LRT (blue lines), IOL with no tilt/decentration (green lines) and IOL with real tilt/decentration (purple lines). Data are for the three subjects, for 5-mm pupils.

Fig. 8

(a) Corresponding Visual Strehl with Astigmatism and 3rd and higher order aberration (b) Corresponding Visual Strehl with 3rd and higher order aberration without Astigmatism (green bars present Simulation with IOL centered, purple bars present simulation with IOL tilt and decentration, blue bars present LRT).