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Scheimpflug Camera-Based Systems

  • Melanie Corbett
  • Nicholas Maycock
  • Emanuel Rosen
  • David O’Brart
Chapter

Abstract

The Scheimpflug principles enable the capture of focused images of objects that are not parallel to the camera and lens, such as a curved cornea. This is achieved by careful movement of the image and lens planes. In the Pentacam, this is achieved by rotation around a central axis and capture of 50 meridional pictures.

Scheimpflug photography images the anterior segment and uses ray-tracing algorithms to provide data on the anterior and posterior corneal surfaces, corneal pachymetry and anterior chamber depth. The effects of misalignment and eye movement can be reduced by using a dual Scheimpflug system with two cameras. The accuracy of measurements can be improved by incorporating Placido imaging into the device.

Keywords

Corneal topography Scheimpflug Ray-tracing algorithms Corneal shape Corneal elevation Corneal pachymetry Anterior chamber depth 

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Melanie Corbett
    • 1
  • Nicholas Maycock
    • 2
  • Emanuel Rosen
    • 3
  • David O’Brart
    • 4
  1. 1.Imperial College Healthcare NHS TrustLondonUK
  2. 2.University Hospital Coventry and WarwickshireCoventryUK
  3. 3.ManchesterUK
  4. 4.Department of OphthalmologySt. Thomas HospitalLondonUK

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