Scanning laser polarimetry and retinal thickness analysis before and after laser in situ keratomileusis.
OBJECTIVE
To evaluate changes in retinal nerve fiber layer (RNFL) thickness after laser in situ keratomileusis (LASIK) using a scanning laser polarimeter with fixed corneal compensation (GDx) and the retinal thickness analyzer (RTA).


METHODS
Thirty-eight eyes of 19 healthy subjects (10 female and 9 male; mean age 37.0-/+8.8 years) underwent GDx and RTA measurements before and after LASIK. All subjects revealed mild to high myopia (mean spherical refraction: -4.0-/+2.75 D). Measurements using GDx were followed by RTA measurements after pupil dilation. All measurements were performed the day before LASIK and 1 week postoperatively.


RESULTS
GDx revealed a decrease in nerve fiber layer thickness measurements after LASIK, but did not reach statistical significance (p>0.05). Using RTA, mean RNFL thickness (MRNFL) and RNFL cross sectional area decreased significantly after LASIK (p=0.03 and p=0.02, respectively).


CONCLUSIONS
Scanning laser polarimetry revealed a slight decrease in RNFL thickness measurements after LASIK. MRNFL and RNFL cross section were significantly lower after LASIK using RTA. The changes might be artifacts in a small group of myopic subjects.
Hoffmann
E M
EM
Department of Ophthalmology, University of Mainz, Mainz - Germany. ehoffman@mail.uni-mainz.de
Dick
H B
HB
Grus
F H
FH
Pfeiffer
N
N
D000328:Adult; D003315:Cornea / Q000601:surgery; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000601:surgery*; D009412:Nerve Fibers / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D011184:Postoperative Period; D011300:Preoperative Care; D012165:Retinal Ganglion Cells / Q000473:pathology*