Objectives: To study the effect of optic asphericity on visual rehabilitation of corneal ectasia with a prosthetic device.
Methods: Subjects with corneal ectasia treated with a fluid-ventilated gas-permeable prosthetic device of diameter 18.0–19.0 mm, who had subjective improvement of good Snellen vision with introduction of optic asphericity, were studied. Best corrected Snellen visual acuity (BCVA) under standard illumination, high contrast visual acuity (HCVA), low contrast visual acuity (LCVA), and wavefront aberrations were measured in a sequence of devices that varied per patient only in presence or amount of ellipsoidal front surface optical eccentricity (FSE).
Results: Five eyes of 5 subjects were studied. (M:F = 3:2; Age: 20–76). Mean steepest SimK was 57.72±8.30 D. BCVA was ≥20/30 in all eyes in all prosthetic devices, regardless of FSE. Although FSE improved BCVA, HCVA, and LCVA in each patient, no optimal amount could be identified in this small series. Asphericity in the form of 0.6 or 0.8 FSE improved HCVA, LCVA, or both in each patient. FSE was associated with a trend toward reduction of higher-order aberrations, particularly coma.
Conclusions: Optic asphericity shows promise for optimization of vision in the rehabilitation of corneal ectasia with a prosthetic device.
Boston Foundation for Sight (T.H., H.G.L., K.G.C., L.J.), Needham, MA; and Harvard Medical School (P.R., D.S.J.), Boston, MA.
Address correspondence and reprint requests to Deborah S. Jacobs, M.D., Boston Foundation for Sight, 464 Hillside Avenue, Suite 205, Needham, MA 02494; e-mail: email@example.com
The authors are salaried full-time employees of the 501(c)3 nonprofit Boston Foundation for Sight, Needham, MA. None of them has proprietary or financial interest in any contact lens or prosthetic device.
Accepted June 19, 2012