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Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile
Published on: September 20, 2024
CustomCornea wavefront retreatment after conventional laser in situ keratomileusis
Gary S Schwartz1, David H Park, Stephen S Lane
1Associated Eye Care, Lake Elmo, Minnesota 55042, USA. gsschwartz@associatedeyecare.com
Purpose:
To evaluate the safety and efficacy of performing laser in situ keratomileusis (LASIK) retreatment using the Alcon CustomCornea system in patients who had prior myopic LASIK using conventional (nonwavefront) software.
Setting:
Private practice ophthalmology clinic, St. Paul, Minnesota, USA.
Methods:
In this prospective interventional trial, consecutive patients having CustomCornea retreatment following conventional LASIK were evaluated. Main outcome measures were uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refractive error, and higher-order aberrations (HOAs).
Results:
Fourteen eyes of 10 patients were evaluated, with a mean follow-up of 5.3 months (range 6.2 to 15.4 months). Mean UCVA improved from 20/50 (logMAR) to 20/26 (P<.001). Mean spherical equivalent changed from -1.45 diopters (D) to +0.52 (P<.00001). Total aberrations, HOAs, defocus, and spherical aberration improved significantly. No eye lost a line of BCVA; 4 eyes (28.6%) gained 1 line, and 1 eye (7.1%) gained 2 lines. Ten eyes (71.4%) were within 0.5 D of emmetropia. Four eyes were overcorrected by 1.00 to 2.00 D. Risk factors for overcorrection included increased HOAs, higher spherical aberration, and not using the surgeon's offset at the time of surgery.
Conclusions:
Wavefront retreatment following conventional LASIK is safe and effective. Care must be taken when treating patients with higher amounts of total aberration, especially spherical aberration. Refractive results are closer to emmetropia when the surgeon's offset is used.
