Corneal collagen crosslinking using riboflavin and ultraviolet-A light for keratoconus: One-year analysis using Scheimpflug imaging
Received 14 July 2008; received in revised form 19 November 2008; accepted 21 November 2008.
Purpose
To evaluate changes in corneal curvature, corneal elevation, corneal thickness, lens density, and foveal thickness after corneal collagen crosslinking with riboflavin and ultraviolet-A (UVA) light in eyes with progressive keratoconus.
Setting
Grewal Eye Institute, Chandigarh, India.
Methods
Subjective refraction, best corrected visual acuity (BCVA), Scheimpflug imaging, and optical coherence tomography were performed preoperatively and 1 week, 1, 3, and 6 months, and 1 year after crosslinking.
Results
There were no significant differences (P > 0.05) in mean values between preoperatively and 1 year postoperatively, respectively, in BCVA (0.22 ± 0.10 and 0.20 ± 0.10), spherical equivalent (−6.30 ± 4.50 diopters (D) and −4.90 ± 3.50 D), or cylinder vector (1.58 × 7° ± 3.8 D and 1.41 × 24° ± 3.5 D). There was no significant difference in mean measurements between preoperatively and 1 year postoperatively, respectively, for central corneal thickness (458.9 ± 40 μm and 455.2 ± 48.6 μm), anterior corneal curvature (50.6 ± 7.4 D and 51.5 ± 3.6 D), posterior corneal curvature (−7.7 ± 1.2 D and −7.4 ± 1.1 D), apex anterior (P = .9), posterior corneal elevation (P = .7), lens density (P = .33), or foveal thickness (175.7 ± 35.6 μm and 146.4 ± 8.5 μm; P = .1).
Conclusions
Stable BCVA, spherical equivalent, anterior and posterior corneal curvatures, and corneal elevation 1 year after crosslinking indicate that keratoconus did not progress. Unchanged lens density and foveal thickness suggest that the lens and macula were not affected after UVA exposure during crosslinking.
From the Grewal Eye Institute (D.S. Grewal, Brar, Jain, Sood, Singla, S.P.S. Grewal), Chandigarh, India; Bascom Palmer Eye Institute (D.S. Grewal), Department of Ophthalmology, University of Miami Miller School of Medicine, Palm Beach Gardens, Florida, and Department of Pediatrics (Singla), University of Illinois at Chicago, College of Medicine, Chicago, Illinois, USA
Corresponding author: Dilraj S. Grewal, MD, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, 7101 Fairway Drive, Palm Beach Gardens, Florida 33418, USA.
No author has a financial or proprietary interest in any material or method mentioned.
Presented in part at the ASCRS Symposium on Cataract, IOL and Refractive Surgery, Chicago, Illinois, April 2008, and the World Ophthalmology Congress, Hong Kong, People's Republic of China, June 2008.
ABSTRACT