title: Individual IOL surface topography analysis by the WaveMaster Reflex UV.
abstract: OBJECTIVE
  In order to establish inspection routines for individual intraocular lenses (IOLs), their surfaces have to be measured separately. Currently available measurement devices lack this functionality. The purpose of this study is to evaluate a new topography measurement device based on wavefront analysis for measuring individual regular and freeform IOL surfaces, the "WaveMaster Reflex UV" (Trioptics, Wedel, Germany).
  
  
  METHODS
  Measurements were performed on IOLs with increasingly complex surface geometries: spherical surfaces, surfaces modelled by higher-order Zernike terms, and freeform surfaces from biometrical patient data. Two independent parameters were measured: the sample's radius of curvature (ROC) and its residual (difference of sample topography and its best-fit sphere). We used a quantitative analysis method by calculating the residuals' root-mean-square (RMS) and peak-to-Valley (P2V) values.
  
  
  RESULTS
  The sample's best-fit ROC differences increased with the sample's complexity. The sample's differences of RMS values were 80 nm for spherical surfaces, 97 nm for higher-order samples, and 21 nm for freeform surfaces. Graphical representations of both measurement and design topographies were recorded and compared.
  
  
  CONCLUSIONS
  The measurements of spherical surfaces expectedly resulted in better values than those of freeform surfaces. Overall, the wavefront analysing method proves to be an effective method for evaluating individual IOL surfaces.
authors.affiliation: Department of Experimental Ophthalmology, Saarland University, Homburg, Germany. marc.kannengiesser@uks.eu
authors.forename: Marc
authors.initials: M
authors.lastname: Kannengießer
authors.forename: Achim
authors.initials: A
authors.lastname: Langenbucher
authors.forename: Edgar
authors.initials: E
authors.lastname: Janunts
mesh_terms: D000465:Algorithms; D019781:Corneal Topography / Q000379:methods*; D006801:Humans; D007910:Lenses, Intraocular; D012372:ROC Curve; D013499:Surface Properties