Related Experiment Video
Updated: Jan 28, 2026

Customizing a Cryolite Glass Prosthetic Eye
Published on: October 31, 2019
Keratoconic eyes with stable corneal tomography could benefit more from custom intraocular lens design than normal
Simon Schröder1, Timo Eppig2, Weidi Liu2,3,4
1Saarland University, Institute of Experimental Ophthalmology, Kirrberger Str. 100, Bldg. 22, D-66424, Homburg/Saar, Germany. Simon.Schroeder@uks.eu.
Abstract:
We investigated whether eyes with keratoconic corneal tomography pattern could benefit more from aberration correction with custom intraocular lenses (IOLs) than normal cataractous eyes despite the effect of misalignment on the correction of aberrations. Custom IOLs (cIOLs) were calculated for twelve normal and twelve keratoconic eyes using personalized numerical ray tracing models. The Stiles-Crawford weighted root-mean-square spot-size (wRMS) at the virtual fovea was evaluated for cIOLs and aberration-neutral IOLs (nIOLs) in a simulated clinical study with 500 virtual IOL implantations per eye and per IOL. IOL misalignment (decentration, tilt, rotation) and pupillary ectopia (4.5 mm iris aperture) were varied upon each virtual implantation. The nIOLs achieved average wRMS of 16.4 ± 4.3 μm for normal, and 92.7 ± 34.4 μm for keratoconic eyes (mean ± standard deviation). The cIOLs reduced the average wRMS to 10.3 ± 5.8 μm for normal, and 28.5 ± 18.6 μm for keratoconic eyes. The cIOLs produced smaller wRMS than nIOLs in most virtual implantations (86.7% for normal and 99.4% for keratoconic eyes). IOL misalignment resulted in larger wRMS variations in the keratoconus group than in the normal group. Custom freeform IOL-optics-design may become a promising option for the correction of advanced aberrations in eyes with non-progressive keratoconic corneal tomography pattern.
Related Concept Videos
Muscles of the Eye
Extraocular Muscles
The six extraocular muscles surround the eyeball and control its movements. They are responsible for a wide range of eye motions, including looking up, down, left, right, and...
Accessory Structures of the Eye
Focusing of Light in the Eye
Benefits of Self-Esteem
Normal Stress
When a rod is under axial loading, the internal forces and corresponding stress are normal to the plane of the section, so it is termed normal stress. It's important to...
Normal Distribution

