This article is more than 5 years old. Information may no longer be current.
Wavefront-guided LASIK treats hyperopia, mixed astigmatism
Results with the AMO Visx laser for hyperopia, compound hyperopic astigmatism and mixed astigmatism were ‘predictable,’ researchers said.
Hyperopia, compound hyperopic astigmatism and mixed astigmatism were safely, effectively and predictably treated with wavefront-guided CustomVue LASIK using the Advanced Medical Optics Visx S4 excimer laser, a retrospective analysis found.
Fred Chien, MD, presented the study he conducted with Edward Manche, MD, at the American Society of Cataract and Refractive Surgery meeting earlier this year. A single surgeon performed all of the CustomVue wavefront-guided LASIK procedures using the Visx S4 excimer laser system, Dr. Chien said.
Hyperopia, compound astigmatism
Dr. Chien reviewed the results of the CustomVue procedure in 34 eyes of 19 patients with hyperopia and compound hyperopic astigmatism.
Preoperatively, he said, the mean spherical error was +1.93 D, with a range of 0.75 D to 3.75 D. The mean cylinder was 0.6 D with a range of 0 D to 2 D, and the mean spherical equivalent was 2.42 D.
At 1 month postoperatively, Dr. Chien said, mean sphere had decreased to –0.04 D, with a range of –1.25 D to 1 D. The mean cylinder was 0.38 D, ranging from 0 D to 1 D, and the spherical equivalent was +0.14 D.
“Efficacy was quite good, with 100% of patients reaching 20/40 or better at 1 month and 100% of patients reaching 20/20 or better at 3 months,” Dr. Chien said. “Predictability was also quite good, with over two-thirds of patients within 0.5 D of emmetropia at both 1 and 3 months and pretty much 100% of patients within 1 D of emmetropia. Safety at 3 months was quite good. We did notice an initial decrease in best corrected visual acuity at the 1-month visits, but no patient lost more than two lines of vision.”
Mixed astigmatism
Dr. Chien also reported the results of the CustomVue procedure in nine eyes of seven patients with mixed astigmatism. Patients’ mean age was 42. Seven eyes were available for follow-up at 1 month.
Preoperatively, Dr. Chien said, the mean spherical refraction in this group was –1.25 D, with a range of –2.75 D to –0.5 D. The mean cylinder was 2.31 D, ranging from 1 D to 3.75 D.
At 1 month, the mean sphere was –0.5 D, ranging from –0.75 D to –0.25 D, and the mean cylinder was 0.36 D, ranging from 0 D to 0.75 D. Spherical equivalent and standard deviation were also reduced.
“Efficacy was excellent, with 100% of eyes achieving 20/30 or better vision at month 1,” Dr. Chien said. “Predictability was quite good, with 86% within 0.5 D of emmetropia and 100% within 1 D of emmetropia.”
He said several patients gained one line of BCVA and none lost lines. Higher-order aberrations appeared to remain constant from preop to postop.
“Wavefront-guided LASIK is effective, predictable and safe for the treatment of hyperopia, compound hyperopic astigmatism and mixed astigmatism using the Visx CustomVue laser,” Dr. Chien concluded.
For more information:
- Fred Chien, MD, can be reached at the Department of Ophthalmology, Standford University, 900 Blake Wilbur Drive, Room 3002, Palo Alto, CA 93404; e-mail: Fred.Chien@mssm.edu.
- Advanced Medical Optics, maker of the Visx Star S4 IR Laser, can be reached at 1700 E. St. Andrew Place, Santa Ana, CA 92705.; 714-247-8200; fax: 714-247-8672; Web site: www.amo-inc.com.
- Katrina Altersitz is an OSN Staff Writer who covers all aspects of ophthalmology.