slide1 l.
Skip this Video
Loading SlideShow in 5 Seconds..
PowerPoint Presentation
Download Presentation

Loading in 2 Seconds...

play fullscreen
1 / 13

- PowerPoint PPT Presentation

  • Uploaded on

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.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about '' - Leo

Download Now An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

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


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?

  • 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
  • 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
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???
  • 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.

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

1. Awwad ST, McCulley JP. Wavefront-guided LASIK: recent developments and results. Int Ophthalmol Clin 2006; 46:27-38

2. Wang L, Chernyak D, Yeh D, Koch DD. Fitting behaviors of Fourier transform and Zernike polynomials. J Cataract Refract Surg 2007; 33:999-1004

3. Ou JI, Manche EE. Zernike versus Fourier treatment tables for myopic patients having CustomVue wavefront laser in situ keratomileusis with the S4 excimer laser. J Cataract Refract Surg 2007; 33:654-657

4. Ciccio AE, Durrie DS, Stahl JE, Schwendeman F. Ocular cyclotorsion during customized laser ablation. J Refract Surg 2005; 21:S772-4

5. Chernyak DA. Cyclotorsional eye motion occurring between wavefront measurement and refractive surgery. J Cataract Refract Surg 2004; 30:633-638.

6. Chernyak DA. From wavefront device to laser: an alignment method for complete registration of the ablation to the cornea. J Refract Surg 2005; 21:463-468

7. Fea AM, Sciandra L, Annetta F, Musso M, Dal Vecchio M, Grignolo FM. Cyclotorsional eye movements during a simulated PRK procedure. Eye 2006; 20:764-768.

8. Swami AU, Steinert RF, Osborne WE, White AA. Rotational malposition during laser in situ keratomileusis. Am J Ophthalmol 2002; 133:561-562.

9. Kermani O. Alignment in customized laser in situ keratomileusis. J Refract Surg 2004; 20:S651-658

10. Chernyak DA. Iris-based cyclotorsional image alignment method for wavefront registration. IEEE Trans Biomed Eng 2005; 52:2032-2040

11. Fay AM, Trokel SL, Myers JA. Pupil diameter and the principal ray. J Cataract Refract Surg 1992; 18:348-351

12. Donnenfeld E. The pupil is a moving target: centration, repeatability, and registration. J Refract Surg 2004; 20:S593-596

13. Yang Y, Thompson K, Burns SA. Pupil location under mesopic, photopic, and pharmacologically dilated conditions. Invest Ophthalmol Vis Sci 2002; 43:2508-2512

14. Eydelman MB, Drum B, Holladay J, Hilmantel G, Kezirian G, Durrie D, Stulting D, Sanders D, Wong B. Standardized analyses of correction of astigmatism by laser systems that reshape the cornea. J Refract Surg 2006; 22:81-95

15. Solomon KD, Fernandez de Castro LE, Vroman DT, Sandoval HP. Importance of iris registration, effect of cyclotorsion, and pupil centroid shift in refractive outcomes after wavefront-guided myopic LASIK. ASCRS Symposium, San Diego, CA, USA, 2007

16. Chang DC. International experience with new iris registration technology and its impact on clinical outcomes. ASCRS Symposium, San Diego, CA, USA, 2007

17. Netto MV, Wilson SE. Corneal wound healing relevance to wavefront guided laser treatments. Ophthalmol Clin North Am 2004; 17:225-231

18. Erie JC, Patel SV, McLaren JW, Ramirez M, Hodge DO, Maguire LJ, Bourne WM. Effect of myopic laser in situ keratomileusis on epithelial and stromal thickness: a confocal microscopy study. Ophthalmology 2002; 109:1447-1452

19. Donnenfeld ED, Nattis A, Fishman GR, Roth J, Stein J, McDonald MB. Effect of cyclotorsion and pupil centroid shift on excimer laser photoablation: analysis of 1000 cases. ASCRS Symposium, San Diego, CA, USA, 2007