Effects of photorefractive keratectomy and cataract surgery on ocular optical errors of higher order

Abstract

Both PRK and cataract surgery are operations which may considerably increase the ocular optical errors of higher order. These aberrations are not predictable and can affect the visual acuity despite optimal sphero-cylindrical correction, in particular under mesopic conditions.

Corneal and total wavefront aberrations in phakic and pseudophakic eyes after implantation of monofocal foldable intraocular lenses

“…One reason might be the higher-order optical aberrations that are present or higher in the pseudophakic eyes than in normal eyes with a natural crystalline lens in loco. 4,5 Corneal topography and wavefront aberrometry are commonly accepted methods to measure aberrations of the cornea and of the entire eye. [5][6][7][8][9][10][11][12][13][14][15][16][17][18] Although wavefront measurements are not capable of measuring edge glare or diffraction, they allow measurement of higher-order aberrations (HOAs) and explanation of some of the visual disturbances.…”

“…One reason might be the higher-order optical aberrations that are present or higher in the pseudophakic eyes than in normal eyes with a natural crystalline lens in loco. 4,5 Corneal topography and wavefront aberrometry are commonly accepted methods to measure aberrations of the cornea and of the entire eye. 5-18 Although wavefront Q 2006 ASCRS and ESCRS Published by Elsevier Inc.…”

Changes in higher-order aberrations after implantation of a foldable iris-claw lens in myopic phakic eyes

“…Several studies confirm that laser refractive surgery induces spherical aberration and coma. [12][13][14][15][16][17][18][19] Thus, evaluation of HOAs after keratorefractive surgery has surfaced in recent years. Oshika et al 1,2 report that refractive keratotomy and laser in situ keratomileusis (LASIK) increase the total wavefront aberration in eyes with 3.0 mm and 7.0 mm pupils and the values did not return to preoperative levels over a 12-month follow-up.…”

Etiology and Clinical Presentation of Astigmatism

“…The measurement of optical aberrations is based on the principle of Tscherning's aberroscope (Mierdel et al, 1999), Hartmann-Shack's aberroscope (Moreno-Barriuso et al, 2001) or light ray tracing (Moreno-Barriuso et al, 2001). The joint representation of all the raw aberroscope data constitutes the spot diagram, which can be taken as a rough estimate of the shape of the retinal point spread.…”