title: Predicting patients' night vision complaints with wavefront technology.
abstract: OBJECTIVE
  To evaluate the accuracy of the diagnostic capabilities of optical metrics generated from wavefront measurements in relationship to post-laser-assisted in situ keratomileusis (LASIK) visual complaints as expressed and drawn by patients.
  
  
  METHODS
  Retrospective analysis and observational case series.
  
  
  METHODS
  Patient wavefront data from an investigational device exemption study for wavefront-guided ablations were used to derive normative modulation transfer function (MTF), encircled energy (EE), and Strehl ratio. These optical metrics and their point-spread functions (PSF) were compared with data from five postoperative patients with night vision complaints. Patients were asked to draw their symptoms, which were elicited by testing with a Fenthoff muscle light, while using their best-corrected distance vision.
  
  
  RESULTS
  The MTF, EE, and Strehl ratio of most patients were markedly different from those of the averages of 208 normal myopic eyes before and after LASIK surgery. The spatial extent of the PSF correlated positively with the severity of the visual complaints. Wavefront-derived PSFs were markedly similar to the patients' drawings.
  
  
  CONCLUSIONS
  The results of this study demonstrate the diagnostic capability of the wavefront system in predicting visual symptoms and complaints of patients with high-order aberrations. Objective visual metrics from patients with night vision complaints were different from those of normal myopic eyes that had undergone LASIK procedures.
authors.affiliation: VISX Inc, Santa Clara, California, USA.
authors.forename: Kuang-Mon Ashley
authors.initials: KM
authors.lastname: Tuan
authors.forename: Dimitri
authors.initials: D
authors.lastname: Chernyak
authors.forename: Sandy T
authors.initials: ST
authors.lastname: Feldman
mesh_terms: D000328:Adult; D003941:Diagnostic Techniques, Ophthalmological; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D008297:Male; D009216:Myopia / Q000601:surgery*; D009755:Night Blindness / Q000175:diagnosis*; D011183:Postoperative Complications; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014792:Visual Acuity