The Impact of the Boston Ocular Surface Prosthesis on Wavefront Higher-Order Aberrations

PURPOSE: To evaluate the effect of the Boston Ocular Surface Prosthesis (Boston Foundation for Sight) on higher-order wavefront aberrations in eyes with keratoconus, eyes that have undergone penetrating keratoplasty, eyes that have undergone refractive surgery, and eyes with ocular surface diseases. DESIGN: Prospective, clinical study. METHODS: The study evaluated 56 eyes of 39 patients with irregular astigmatism who were treated with the Boston Ocular Surface Prosthesis when conventional treatments failed. Patients were sorted into 4 clinical groups based on the underlying cause of irregular astigmatism, including keratoconus (group 1), post penetrating keratoplasty (group 2), post refractive surgery (group 3), and ocular surface diseases (group 4). Another 6 eyes of 5 patients who were treated with rigid gas permeable lenses also were evaluated. Best-corrected visual acuity; topographic refractive indices, including spherical, cylindrical, spherical equivalent values; and higher-order and total wavefront aberration errors were noted at baseline and after fitting the lens. RESULTS: In all groups, higher-order wavefront aberration error was noted to decrease significantly in eyes wearing the Boston Ocular Surface Prosthesis (P < .001, P = .001, P = .002, and P = .001, respectively). By post hoc analysis, significant differences in the level of higher-order aberrations were observed only between groups 1 and 4 (P = .012) and groups 1 and 2 (P = .033). In the overall group, mean correction rate of higher-order aberration error with the Boston Ocular Surface Prosthesis was 72.3%. However, in eyes with rigid gas permeable lenses, 2 eyes demonstrated increased higher-order aberration error, whereas the mean correction rate in other 4 eyes was only 42.5%. CONCLUSIONS: With its unique structure, the Boston Ocular Surface Prosthesis was found to be very effective in reducing higher-order wavefront aberrations in patients with irregular astigmatism resulting from a number of corneal and ocular surface conditions who had not responded satisfactorily to conventional methods of optical correction. (Am J Ophthalmol 2011;151:682-690. (C) 2011 by Elsevier Inc. All rights reserved.)