title: Determining postoperative anterior chamber depth.
abstract: OBJECTIVE
  To compare measured and calculated postoperative anterior chamber depths (ACDs).
  
  
  METHODS
  Department of Ophthalmology and Institute of Medical Physics, University of Vienna, Vienna, Austria, and Department of Ophthalmology, University of Mainz, Mainz, Germany.
  
  
  METHODS
  The postoperative ACD was measured in 189 pseudophakic eyes using a laboratory prototype of partial coherence interferometry (PCI). In 6 intraocular lens (IOL) groups, the mean ACD was calculated by ray tracing based on the best-known A-constants of the SRK formulas. In addition, for each IOL type, each measured ACD was compared with a value calculated using the individual spherical equivalent of the postoperative refraction.
  
  
  RESULTS
  The measured and the calculated ACD values were close and did not show systematic differences. The ACD values obtained in the study, however, differed significantly from the values published by the IOL manufacturers. A comparison of the PCI-assessed ACDs and the calculated values using the postoperative refraction showed more scattered results for the refraction-based data, which was probably the result of higher measurement errors with the autorefractometer than with PCI.
  
  
  CONCLUSIONS
  High-precision interferometry measurements and ray-tracing calculations confirmed each other. The resulting mean ACD values should be used instead of the manufacturers' values. The refractive outcome of cataract surgery can be improved by combining preoperative high-precision PCI biometry and numerical ray tracing for IOL power calculations.
authors.affiliation: Department of Ophthalmology, University of Vienna, Vienna, Austria.
authors.forename: Katharina
authors.initials: K
authors.lastname: Kriechbaum
authors.forename: Oliver
authors.initials: O
authors.lastname: Findl
authors.forename: Paul Rolf
authors.initials: PR
authors.lastname: Preussner
authors.forename: Christina
authors.initials: C
authors.lastname: Köppl
authors.forename: Jochen
authors.initials: J
authors.lastname: Wahl
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Drexler
mesh_terms: D000867:Anterior Chamber / Q000033:anatomy & histology*; D001699:Biometry / Q000379:methods; D006801:Humans; D007368:Interferometry; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008027:Light; D008962:Models, Theoretical; D011184:Postoperative Period; D019591:Pseudophakia / Q000150:complications