title: [Aberrometry due dilated pupils--Which mydriatic should be used?].
abstract: BACKGROUND
  For a wavefront-based LASIK procedure aberrometric measurements are necessary via a dilated pupil. The more dilated the pupil is the more aberrations can be identified. There are different mydriatic eyedrops used to dilate the pupil. It is unclear so far which mydriatic is best for measuring aberrations before LASIK.
  
  
  METHODS
  We performed aberrometry measurements on 50 eyes under the following different conditions: physiological mydriasis under mesopic environment, tropicamide-induced dilation, phenylephrine-induced dilation, and cyclopentolate-induced dilation. The wavefront measurements were compared with the respective subjective refraction (sr).
  
  
  RESULTS
  The refractive myopic error measured by aberrometry was less than after subjective refraction depending on the mydriatic used. Phenylephrine-induced mydriasis resulted in 0.19 D less myopia, tropicamide induced 0.35 D less myopia, and cyclopentolate 0.42 D less on the average. The aberrometry measurements under mesopic conditions led to 0.24 D less myopia than measured subjectively.
  
  
  CONCLUSIONS
  Using cyclopentolate eyedrops wavefront analysis results in a considerable difference in the preoperative refractive error compared to the standard subjective refraction. Regarding the average differences in refraction the aberrometry measurements after neosynephrine-induced dilation of the pupil usually resemble the subjective refractive error. For practical reasons we would like to recommend aberrometry measurements under mesopic conditions without applying mydriatics provided the pupillary diameter is at least 6 mm.
authors.affiliation: Klinik für Augenheilkunde Martin-Luther-Universität Halle-Wittenberg, Germany.
authors.forename: Susan
authors.initials: S
authors.lastname: Giessler
authors.forename: Thomas
authors.initials: T
authors.lastname: Hammer
authors.forename: Gernot I W
authors.initials: GI
authors.lastname: Duncker
mesh_terms: D000328:Adult; D003519:Cyclopentolate / Q000008:administration & dosage; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ / Q000379:methods*; D008297:Male; D009184:Mydriatics / Q000008:administration & dosage*; D009216:Myopia / Q000175:diagnosis / Q000601:surgery*; D009883:Ophthalmic Solutions; D010656:Phenylephrine / Q000008:administration & dosage; D011680:Pupil / Q000187:drug effects*; D012016:Reference Values; D012029:Refraction, Ocular; D012680:Sensitivity and Specificity; D014331:Tropicamide / Q000008:administration & dosage
chemical_list: D009184:Mydriatics; D009883:Ophthalmic Solutions; D010656:Phenylephrine; D003519:Cyclopentolate; D014331:Tropicamide