title: Effect of pupillary dilation on retinal nerve fiber layer thickness measurements using optical coherence tomography.
abstract: OBJECTIVE
  To evaluate the effect of pupillary dilation on retinal nerve fiber layer thickness (RNFL) measurements using optical coherence tomography (OCT-3).
  
  
  METHODS
  Randomly chosen eyes of healthy individuals were scanned before and after pupillary dilation by two trained operators (R.G.O., R.V.) using OCT-3 (Carl Zeiss Meditec, Inc., Dublin, CA). Fast and regular RNFL (256 A-scans) OCT-3 protocols (software version A1.1) were used in each scanning session. RNFL thickness measurements before and after dilation were compared.
  
  
  RESULTS
  Ten eyes of 10 subjects (6 females, 4 males) were enrolled. Mean age was 32.0 +/- 11.2 years (range, 21 to 52 years). Mean pupillary diameter before and after dilation was 2.9 +/- 0.6 mm and 7.6 +/- 0.8 mm, respectively (P < 0.0001, paired t-test). There was no significant difference in RNFL thickness measurements before and after dilation using both fast and regular RNFL protocols (P > or = 0.05 for all comparisons, paired t-test). Mean coefficients of variation for mean RNFL thickness measurements were 15.3% before and 13.7% after dilation for operator 1; and 10.8% before and 12.7% after dilation for operator 2 for the fast RNFL protocol and 11.3% versus 10.4% and 12.9 versus 11.1%, respectively, for the regular RNFL protocol.
  
  
  CONCLUSIONS
  Pupillary dilation is not necessary in all subjects to obtain reproducible RNFL thickness measurements using OCT-3.
authors.affiliation: Department of Ophthalmology, The New York Eye and Ear Infirmary, New York, NY, USA.
authors.forename: Samiah
authors.initials: S
authors.lastname: Zafar
authors.forename: Rabia
authors.initials: R
authors.lastname: Gurses-Ozden
authors.forename: Roberto
authors.initials: R
authors.lastname: Vessani
authors.forename: Manchima
authors.initials: M
authors.lastname: Makornwattana
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Liebmann
authors.forename: Celso
authors.initials: C
authors.lastname: Tello
authors.forename: Robert
authors.initials: R
authors.lastname: Ritch
mesh_terms: D000328:Adult; D003936:Diagnosis, Computer-Assisted; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000000981:diagnostic imaging*; D011680:Pupil / Q000502:physiology*; D012016:Reference Values; D012160:Retina / Q000648:ultrastructure*; D012984:Software; D041623:Tomography, Optical Coherence; D014463:Ultrasonography