Leo J. Maguire
"To avoid aberration in the center of the visual field, the cornea must be regular over the entrance pupil".
"When the cornea is irregular over the entrance pupil, the image generated by the cornea loses contrast and edge definition".
"The final result is that corneal irregularity from refractive surgery can cause optical degradation; and optical performance in the central field can change with pupil size".
"To avoid aberration in more peripheral portions of the visual field, the cornea must be regular over the cornea adjacent to the entrance pupil as well as over the entrance pupil itself."
"First, the pupil enlarges. As it does, aberration of central vision increases as more distorted paracentral cornea falls within the pupillary space."
"The problems with pupil-related aberration are further magnified by the reality that the Stiles-Crawford effect is negated in night vision."
"I hope the reader will understand how a patient may have clinically acceptable 20/20 visual acuity in the daytime and still suffer from clinically dangerous visual aberration at night if that patient's visual system must cope with an altered refractive error, increased glare, poorer contrast discrimination, and preferentially degraded peripheral vision. People die at night in motor vehicle accidents four times as frequently as they do during the day, and these figures are adjusted for miles driven. Night driving presents a hazardous visual experience to adults without aberration. When we discuss aberration at night we are considering a possible morbid effect of refractive surgery."