Impact of Spherical Aberration on Visual Quality and Depth of Focus in Pseudophakic Eyes

Journal:
Journal of Cataract & Refractive Surgery
Year:
2023
Authors:
Kozhaya, Karim; Kenny, Peter I.; Esfandiari, Saina; Wang, Li MD; Weikert, Mitchell P.; Koch, Douglas
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Purpose: 

Assess the performances of four intraocular lenses (IOLs) in various spherical aberration (SA) conditions, using the VAO adaptive optics simulator (Voptica S.L.).

Setting: 

Cullen Eye Institute, Baylor College of Medicine, Houston, TX.

Design: 

Prospective case series.

Methods: 

Distance-corrected visual acuities at distance (CDVA), intermediate (DCIVA), and near (DCNVA) were measured in 42 dilated pseudophakic eyes at baseline and with ocular SA ranging from –0.4 to +0.4 μm in increments of 0.2 μm (6.0-mm pupil). Four IOL types were assessed: monofocal IOLs with zero-SA, enhanced-monofocal, extended depth-of-focus (EDoF), and continuous-range-of-vision.

Results: 

Compared to SA = 0μm, significant changes (all P<.05) were: 1) zero-SA monofocal IOLs’ DCNVA at high contrast improved by 0.13 logMAR with SA = – 0.4 μm and worsened by 0.09 and 0.10 logMAR with SA = +0.2 and +0.4 μm, respectively. DCNVA at low contrast worsened by 0.09 logMAR with SA = +0.4 μm; and 2) with SA = –0.4 μm, the enhanced monofocal IOL lost 0.06 logMAR of CDVA at high contrast and gained 0.09 logMAR of DCNVA at low contrast. There were no significant changes from SA = 0 μm for EDoF and continuous-range-of-vision IOLs.

Conclusions: 

Zero-SA and EDoF IOLs were the most and least sensitive to SA modulation, respectively. In perfect optical systems where all the optical elements are aligned, induction of targeted amounts of negative SA improved the depth of focus of some IOL types. We found no benefit with positive SA.