title: Evaluating the effect of pupil dilation on spectral-domain optical coherence tomography measurements and their quality score.
abstract: BACKGROUND
  Spectral-domain optical coherence tomography (SD-OCT) provides fast scan speed and high scan resolution improving its diagnostic accuracy. The purpose of this study was to evaluate if SD-OCT measurements and their quality score are influenced by pupil dilation.
  
  
  METHODS
  Retinal nerve fiber layer thickness (RNFL), ganglion cell complex (GCC) and optic nerve head (ONH) were measured in one eye of 57 glaucoma patients and 36 healthy subjects using spectral domain optical coherence tomography (SD-OCT) before and after pupil dilation. Comparisons were made between measurements and their quality score pre- and post dilation (Signal Strength Index, SSI). Overall RNFL, average GCC and ONH rim volume were considered in the analysis.
  
  
  RESULTS
  No statistically significant differences were found between pre- and post-dilation measurements in both groups (glaucoma: RNFL 80 ± 15 μm vs 80 ± 16 μm, p = 0.87; GCC 81.35 ± 13.4 μm vs 81.10 ± 13.14 μm, p = 0.92; ONH 0.05 ± 0.11 mm(3) vs 0.04 ± 0.07 mm(3), p = 0.74; controls RNFL 99 ± 12 μm vs 98 ± 14 μm, p = 0.70; GCC 92.12 ± 6.7 μm vs 91.54 ± 7.05 μm, p = 0.72; ONH 0.11 ± 0.1 mm(3) vs 0.04 ± 0.07 mm(3), p = 0.36) nor between pre- and post-dilation quality score (glaucoma SSI RNFL 54.3 ± 10.3 vs 51.7 ± 18.1, p = 0.12; SSI GCC 58 ± 9.5 vs 57 ± 8.09, p = 0.55; SSI ONH 48.5 ± 7.6 vs 46.6 ± 7.2, p = 0.16; controls SSI RNFL 57 ± 10.3 vs 54 ± 9.31, p = 0.2; SSI GCC 60.9 ± 8.1 vs 58.8 ± 7.3, p = 0.3; SSI ONH 51.5 ± 8.9 vs 50.4 ± 8.3, p = 0.59).
  
  
  CONCLUSIONS
  Pupil dilation doesn't affect SD-OCT measurements and their quality score.
authors.affiliation: IRCCS-Fondazione GB Bietti, Via Livenza 3, 00198, Rome, Italy. lucia.tanga@gmail.com.
authors.forename: Lucia
authors.initials: L
authors.lastname: Tanga
authors.affiliation: IRCCS-Fondazione GB Bietti, Via Livenza 3, 00198, Rome, Italy. gloriaroberti82@gmail.com.
authors.forename: Gloria
authors.initials: G
authors.lastname: Roberti
authors.affiliation: IRCCS-Fondazione GB Bietti, Via Livenza 3, 00198, Rome, Italy. oddonef@gmail.com.
authors.forename: Francesco
authors.initials: F
authors.lastname: Oddone
authors.affiliation: DSMC, Università degli studi di Brescia USVD "Centro per lo studio del Glaucoma", P.le Spedali Civili, 1 - 25123, Brescia, Italy. quaranta@med.unibs.it.
authors.forename: Luciano
authors.initials: L
authors.lastname: Quaranta
authors.affiliation: IRCCS-Fondazione GB Bietti, Via Livenza 3, 00198, Rome, Italy. manuela.ferrazza@gmail.com.
authors.forename: Manuela
authors.initials: M
authors.lastname: Ferrazza
authors.affiliation: IRCCS-Fondazione GB Bietti, Via Livenza 3, 00198, Rome, Italy. berardo.francesca@gmail.com.
authors.forename: Francesca
authors.initials: F
authors.lastname: Berardo
authors.affiliation: DSCMT, Università di Roma Tor Vergata, Viale Oxford 81, 00133, Rome, Italy. gianlucamanni53@gmail.com.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Manni
authors.affiliation: IRCCS-Fondazione GB Bietti, Via Livenza 3, 00198, Rome, Italy. marco.centofanti@fastwebnet.it.|DSCMT, Università di Roma Tor Vergata, Viale Oxford 81, 00133, Rome, Italy. marco.centofanti@fastwebnet.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Centofanti
mesh_terms: D000368:Aged; D005260:Female; D005901:Glaucoma / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D009184:Mydriatics / Q000008:administration & dosage*; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis; D011680:Pupil / Q000187:drug effects*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000592:standards*; D014331:Tropicamide / Q000008:administration & dosage
chemical_list: D009184:Mydriatics; D014331:Tropicamide