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Beyond the Dresden Protocol: Optimization of Corneal Cross-Linking for Visual Function

  • Grace Lytle
  • John Marshall
Chapter

Abstract

Corneal cross-linking (CXL) is a minimally invasive, conservative intervention for the treatment of progressive keratoconus that offers the opportunity to preserve visual function by slowing disease progression. A conventional treatment protocol, Dresden CXL, has been established as a first line treatment for keratoconus, and has been demonstrated to be safe and effective in randomized controlled clinical trials. This chapter provides an overview of modifications to the conventional Dresden CXL protocol aimed at shortening treatment time, improving clinical workflow, expanding access to the procedure to patients with thinner corneas, and targeting improved visual function in addition to stabilization. Parameter modifications discussed include adjustments to UVA irradiance, total energy dose, pulsed illumination and customized UV beam shaping. The chapter explores these modifications in the context of the photochemical mechanisms of cross-linking and evaluates the theoretical impact of each modification on the spatial distribution of cross-link bonds formed within the corneal stroma. Clinical evidence for the impact of each modification will be presented, and practical clinical implications are discussed.

Keywords

Cross-linking Accelerated cross-linking Pulsed cross-linking Customized cross-linking Riboflavin Keratoconus Normalization CuRV PiXL Mosaic Photochemical mechanisms Demarcation line Oxygen UVA 

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Grace Lytle
    • 1
  • John Marshall
    • 2
  1. 1.AvedroWalthamUSA
  2. 2.Institute of Ophthalmology University College London in association with Moorfields Eye HospitalLondonUK

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