Browse by author
Lookup NU author(s): Professor Francisco FigueiredoORCiD
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
PURPOSE: To determine the higher order aberrations at the corneal first surface before and after surgery for pterygium. METHODS: Data were drawn from a longitudinal study of patients undergoing pterygium excision at Royal Victoria Infirmary, Newcastle upon Tyne, England between September 1998 and May 2004. Corneal topography was taken with the TMS-2 Topographic Modeling System (Computed Anatomy Corp) prior to and 6 months after surgery, exported to VOLPro software v7.08 (Sarver & Associates), and wavefront aberrations were derived for a 5.0-mm pupil using a 10th order Zernike polynomial expansion. Pre- to postoperative changes were assessed for significance using analyses of variance, and the relative risk of significant postoperative aberrations by pterygium size was determined. RESULTS: Satisfactory corneal topography was available on 67 eyes (mean age 53.8 +/- 16.7 years [range:, 25-86 years]). The root-mean-square (RMS) fit error in preoperative eyes was 0.15 +/- 0.10 mu m. Preoperatively the total higher order RMS wavefront aberration was 0.94 +/- 0.83 pm. All Zernike modes were elevated; with trefoil being the major contributor 0.52 +/- 0.50 mu m. Pterygium excision significantly reduced wavefront aberrations across all modes and orders (F-1,F-129=6.7 to 22.6, P <.01): total higher order RMSpostop 0.45 +/- 0.35 mu m. Cases with visually significant postoperative aberrations occurred and were more likely with larger pterygia:relative risk compared to pterygia 1.0 to 1.9 mm was 1.3 13.3 for 4.0 for 2.0 to 2.9 mm, 8.5 for 3.0 to 3.9 mm, to 4.9 mm and 10.2 for 5 0 to 5 9 mm. CONCLUSIONS- Zernike polynomial fitting well describes wavefront aberrations in eyes with pterygia. Pterygia are associated with wavefront aberrations, especially trefoil, but these were largely eliminated by surgery. Earlier excision of pterygia reduces the likelihood of significant residual aberrations.
Author(s): Pesudovs K, Figueiredo FC
Publication type: Conference Proceedings (inc. Abstract)
Publication status: Published
Conference Name: 7th International Congress of Wavefront Sensing and Optimized Refractive Corrections
Year of Conference: 2006
Pages: 921-925
ISSN: 1081-597X
Publisher: Journal of Refractive Surgery: Slack, Inc.
Library holdings: Search Newcastle University Library for this item
ISBN:
