Expanded
Range CustomCornea Algorithms for Myopia and Astigmatism: One-month
Results
Francesco Carones, MD; Luca Vigo, MD; Elena Scandola, MD; Sergio G. Sorace, MD
Page 1 of 1
Date:
22/03/2007
PURPOSE:
To evaluate the early clinical results achieved with an algorithm adjusted for an expanded
range of correction in wavefront-guided customized
ablation with the LADARVision4000 (Alcon Laboratories Inc, Fort Worth, Tex).
METHODS: Fifty-five consecutive eyes from 31 patients underwent wavefront-guided, customablation
laser in situ keratomileusis (LASIK)
(Hansatome and BD 4000 microkeratomes, LADARWave aberrometer, LADARVision4000 laser
system). These were normal myopic and astigmatic eyes that had never been operated on. The spherical
equivalent refractive error was +0.30 to -8.13 diopters (D) (mean -4.26 ± 2.14 D) and the astigmatism
ranged from 0 to -3.75 D (mean -0.97 ± 0.96 D). All eyes were treated according to the
CustomCornea protocol using the commercial LADARVision4000 platform. Patients were followed
for at least 2 months and standard visual measurements were taken and recorded at 1 day and 1, 3,
and 6 months after treatment. The results of treatment were assessed using the following
parameters: uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA); manifest
spherical equivalent refractive error; wavefront
measurement of high order aberrations; and subjective reports of visual symptoms by
patients.
RESULTS: One month after LASIK, the mean manifest spherical equivalent refractive error was
-0.18 ± 0.41 D. Seventy-eight percent and 96% of eyes had manifest spherical equivalent refractive
error within ±0.50 D and ±1.00 D of attempted correction, respectively, with 78% of eyes with 20/20 or
better UCVA. Eyes with 20/16 and 20/12.5 BSCVA were 89% and 36%, respectively (55% and 7%
preoperatively). The mean high order aberrations rootmean-square was 0.34 ± 0.10 µm preoperatively and
0.35 ± 0.09 µm postoperatively (6.0-mm pupil size). High order aberrations were either reduced,
unchanged, or increased by <10% in 58% of eyes. From the Carones Ophthalmology Center,
Milan, Italy.
Dr Carones is a paid consultant for Alcon Laboratories Inc. The other authors do not have any financial or proprietary interest in the company
or products described in this manuscript.
CONCLUSIONS: The new optimized algorithm for higher refractive errors appears to be effective
in improving BSCVA, and a minority of patients demonstrated an increase in the magnitude of
high order aberrations when compared to preoperative aberrometry. A slight spherical equivalent
refraction undercorrection will be addressed with future nomogram adjustments.
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