UT Southwestern Medical Center at Dallas Department of Ophthalmology

1. The Relationship Between Anterior and Posterior Corneal Higher-Order Aberrations and Ocular Wavefront Aberrations UT Southwestern Medical Center at DallasDepartment of Ophthalmology Zev Shulkin, M.D., Orkun Muftuoglu, M.D., Michael Coleman MS4, Vinod Mootha, M.D., Steven M. Verity, M.D., R. Wayne Bowman, M.D., H. Dwight Cavanagh, M.D., PHD, James P. McCulley, M.D.

2. Financial Disclosure • UT Southwestern Medical Center & Aston Ophthalmology Clinic, Dallas, TX. • Financial Disclosure for all authors: Drs. Bowman, Verity, and McCulley-Alcon Consultants • Dr. Cavanaugh receives research reimbursements from Ciba and Menion. • None of the authors have financial interest in the subject matter of this poster. • Acknowledgements: Supported in part by an unrestricted research grant from Research to Prevent Blindness, Inc., New York, New York.

3. INTRODUCTION • Recent technologic advances have given us the ability to image the anterior segment and the entire eye • Applications of data from these new tools is being utilized in surgical cases • We used two new office-based imaging devices to investigate the relationship between anterior/posterior corneal higher-order aberrations and ocular higher-order aberrations. 

4. Devices -The Scheimpflug camera (Pentacam Oculus Wetzlar, Germany) utilizes 5 rotating cameras to provide anterior and posterior topographic maps of the cornea, corneal pachmetry, tomography, IOL calculations, and lens density -The AMO Wavescan aberrometer uses Hartmann-Shack data points for wavefront error reconstruction. -Both devices provide ocular higher order aberration data

5. Purpose -To investigate the relationship between anterior/posterior corneal higher-order aberrations and ocular higher-order aberrations. 

6. METHODS • Retrospective • 111 eyes of 56 patients • Anterior and posterior corneal higher order aberrations were obtained from the central 6.0 mm zone. These measurements were compared with higher order aberrations of the entire eye, using the Wavescan aberrometer • Diseased eyes and eyes with cataractous lenses were excluded • Correlation analysiswas performed to investigate the aberration symmetry between the right and left eyes and to assess the association between anterior and posterior corneal, and ocular higher order aberrations. • All statistical analyses were performed using Pearson two-tailed analysis. 

7. Results • We found a statistically significant correlation between ocular spherical aberration and both anterior and posterior corneal spherical aberration • There was no correlation between anterior and posterior corneal coma, trefoil higher order aberrations, and total ocular higher order aberrations. 

8. Coma r=0.021, p=0.83 r=0.002, p=0.98

9. Spherical Aberration r=0.41, p=<0.01 r=0.32, p=<0.01

10. Trefoil r=0.097, p=0.313 0.013, p=0.891

11. Total HOAs r=0.032, p=0.738 r=0.229, p=0.016

12. Conclusion • Anterior and posterior corneal spherical aberration measurements with Scheimpflug cameras are compatible with entire ocular spherical aberration measurement.  • On the other hand, anterior and posterior corneal Coma and Trefoil measurements did not have significant compatability with ocular HOA measurements. • References: Mike P. Holzer, MD; Martin Sassenroth; Gerd U. Auffarth, MD, Journal of Cataract and Refractive Surgery “Reliability of Corneal and Total Wavefront Aberration Measurements With the SCHWIND Corneal and Ocular Wavefront Analyzers,” 10/26/2006 pgs 917-920 Xu Cheng, Nikole L. Himebaugh, Pete S. Kollbaum, Larry N. Thibos, and Arthur Bradley, Test–Retest Reliability of Clinical Shack-Hartmann Measurements, IOVS, Jan 2004, Vol 45, No.1 351-360 www.amo.com www.oculus.com