Imagine being able to offer your presbyopic patients better depth of focus by altering the aberrations in their eyes. Much of our research was centered on trying to understand the role that certain aberrations play in a patient’s depth of field. If you have no accommodation, but you have some aberrations, then there’s a degree of multifocality that might give you an expanded depth of field to see a range of visual target. Wavefront testing has proven to be a useful technology to assess these higher-order aberrations (HOAs) and to better understand the limitations of visual function.
Adaptive optics (AO) was originally designed for use in astronomy but is finding its way into ophthalmology and our clinical practice. AO visual simulator technology takes the wavefront signal and, through a special deformable mirror, cancels out whatever wavefront error it detects. Because imperfections in the cornea and lens are unavoidable, AO compensates for the irregularities and improves visual function. This can offer the patient a perfect optical pathway and can also be used by practitioners to look at the retina. In highly aberrated eyes, AO allows you to show patients a simulation of what their vision could be if the errors are corrected.
We found that the generation of the right amount of spherical aberration enhances depth of focus. Our goal is to find what the best aberration pattern is for maintaining good optical quality and enhancing the depth of field. We anticipate that AO technology will help determine the most functional aberration values for the typical presbyopic patient, which will contribute significantly to the design of presbyopic corneal and lens-based treatments.
1. Rocha KM, Vabre L, Harms F, et al. Effects of Zernike wavefront aberrations on visual acuity measured using electromagnetic adaptive optics technology. J Refract Surg. 2007;23(9):953-959.
2. Rocha KM, Vabre L, Chateau N, Krueger RR. Expanding depth of focus by modifying higher-order aberrations as induced by an adaptive optics visual simulator. J Cataract Refract Surg. 2009;35(11):1885-1892.
3. Rocha KM, Vabre L, Chateau N, Krueger RR. Enhanced visual acuity and image perception following correction of highly aberrated eyes using an adaptive optics visual simulator. J Refract Surg. 2010;26(1):52-56.
4. Rocha KM, Soriano ES, Chamon W, Chalita MR, Nosé W. Spherical aberration and depth of focus in eyes implanted with aspheric and spherical intraocular lenses: a prospective randomized study. Ophthalmology. 2007;114(11):2050-4.