title: Evaluation of 4 corneal astigmatic marking methods.
abstract: OBJECTIVE
  To compare 4 devices used to mark the cornea before astigmatism-reducing surgery.
  
  
  METHODS
  Hanusch Krankenhaus, Vienna, Austria.
  
  
  METHODS
  Randomized examiner-masked clinical trial.
  
  
  METHODS
  Patients were randomly allocated to 1 of 4 groups for preoperative corneal marking in the sitting position. The 4 methods used were marking at the slitlamp with an insulin needle, a pendular marker, a bubble marker, and a tonometer marker. The marks were then documented with a standardized photographic technique, and the rotational deviation and vertical misalignment were assessed.
  
  
  RESULTS
  The study enrolled 60 patients. The pendular-marking device showed the least rotational deviation to the reference meridian (mean 1.8 degrees). There was no statistically significant difference between slitlamp marking and pendular marking (P = .05); however, there was a significant difference between the pendular marker and the bubble marker and between the pendular marker and the tonometer marker (P = .01 and P < .01, respectively). The least vertical misalignment was observed with the slitlamp-marking device (mean 0.28 mm). There was no statistically significant difference in vertical misalignment between the 4 groups.
  
  
  CONCLUSIONS
  All marking devices showed a slight deviation to the horizontal reference meridian. Because small deviations of the meridian can result in a relevant reduction in the astigmatism-reducing effect with toric intraocular lenses, accurate marking of the cornea before surgery is critical due to the variable cyclotorsion caused by a change from the upright to the supine position.
  
  
  BACKGROUND
  No author has a financial or proprietary interest in any material or method mentioned.
authors.affiliation: Vienna Institute for Research in Ocular Surgery, Karl Landsteiner Institute, Hanusch Hospital, Vienna, Austria.
authors.forename: Nina
authors.initials: N
authors.lastname: Popp
authors.forename: Nino
authors.initials: N
authors.lastname: Hirnschall
authors.forename: Sophie
authors.initials: S
authors.lastname: Maedel
authors.forename: Oliver
authors.initials: O
authors.lastname: Findl
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001251:Astigmatism / Q000175:diagnosis* / Q000601:surgery; D002386:Cataract / Q000150:complications; D002387:Cataract Extraction / Q000295:instrumentation*; D003315:Cornea / Q000473:pathology*; D004311:Double-Blind Method; D005260:Female; D057918:Fiducial Markers; D006801:Humans; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D011187:Posture; D011446:Prospective Studies