Transcript Postoperative month 3

Wavefront-Guided LASIK Using the VISX
CustomVue™ Star S4 Laser System With and
Without Iris Registration™:
A Retrospective Comparative Study
Sonal B. Dave, MD
Ladan Espandar, MD
Majid Moshirfar, MD
John A. Moran Eye Center
Salt Lake City, Utah
Purpose
To compare visual outcomes after laser in situ
keratomileusis (LASIK) using the VISX Star S4
CustomVue™, with and without Iris
Registration™ (IR) technology.
Is there a difference
between Iris
Registration™ and
non-Iris Registration™
LASIK?
Methods
• Retrospective study
• 239 myopic eyes of 142 patients with or without astigmatism
underwent LASIK
• Primary LASIK treatment with the VISX Star S4
CustomVue™ laser (VISX Incorporated, Santa Clara, CA)
with or without Iris RegistrationTM technology
• 121 eyes with IR
• 118 without IR
• Primary outcome measures: uncorrected visual acuity
(UCVA), best spectacle-corrected visual acuity (BSCVA), and
manifest refraction
• Secondary outcome measures: higher-order aberrations (HOA)
and vector analysis of residual astigmatism
UCVA 6 months post LASIK
6 months post LASIK
Postoperative month 3 (±0.5 D lines)
Change in BSCVA (Snellen lines) 6 months postoperatively
Results
• At 6 months, the mean values for logMAR UCVA:
– 0.00 ± 0.09 in the IR group
– -0.01 ± 0.11 in the non-IR group (p=0.587)
• UCVA of 20/20 or better:
– 79% of eyes in the IR group
– 73% in the non-IR group (p=0.518)
• Within ±0.5 D of emmetropia:
– 92% of the eyes in the IR group
– 90% in the non-IR group (p=0.999)
• Mean postoperative absolute changes in total root mean square (RMS)
higher order aberrations HOA (μm):
– IR group 0.22
– non-IR group 0.19 (p=0.6)
• At 3 months, the mean magnitude of error of surgically induced
astigmatism:
– -0.09 in the IR group
– -0.04 in the non-IR group (p=0.24)
Why did IR not have better outcomes?
• Eyes were marked at the limbus and patients
were adjusted accordingly
• IR was performed prior to lifting of flaps
resulting in possible patient movement after
iris verification
• Stromal remodeling and epithelial hyperplasia
may mask benefits of IR
• Other thoughts???
Conclusions
• Wavefront-guided LASIK with the VISX Star S4
CustomVue™ laser system, independent of Iris
Registration™ status, is effective, safe, and
predictable.
• This study did not find any statistical significance
supporting the better achievement of visual acuity,
astigmatism correction, or the lesser induction of
HOA using Iris Registration™ in comparison to a
non-Iris Registration™ system.
References
Supported in part by an unrestricted grant from Research To Prevent Blindness, Inc., New York,
NY, to the Department of Ophthalmology and Visual Sciences, University of Utah
http://joneseyecenters.com/images/content/joneseyecenters/Iris_Registration_Image.jpg
http://www.cullomeyecenter.com/images/content/visxS3_fullview_sm.jpg
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