Repeatability of autorefraction and axial length measurements after laser in situ keratomileusis.
OBJECTIVE
To assess the repeatability and agreement of refractive error measurements and the repeatability of axial length (AL) measurements in patients after laser in situ keratomileusis (LASIK).


METHODS
The Ohio State University College of Optometry, Columbus, Ohio, USA.


METHODS
Subjective refraction, autorefraction measurements with the Grand Seiko and Humphrey autorefractors, and AL measurements with the IOLMaster were completed for 40 previously myopic LASIK patients under noncycloplegic and cycloplegic conditions on 2 separate occasions.


RESULTS
The mean difference between visits for axial length measurements was 0.008 mm +/- 0.04 (SD). The between visits repeatability for all refractive error measurements were <0.75 diopter (D). The mean difference between the subjective refraction and the Humphrey autorefractor for spherical equivalent was statistically significant under noncycloplegic conditions (-0.90 D, P<.0001) and cycloplegic conditions (-2.05 D, P<.0001). The mean difference between subjective refraction and Grand Seiko autorefraction measurements was not significant under noncycloplegic conditions (+0.05 D, 95% limits of agreement [LoA]=-0.99, 1.09; P=.52) conditions but was statistically significant, but not clinically relevant, under cycloplegic conditions (+0.17 D, 95% LoA=-0.73, 1.07; P=.03).


CONCLUSIONS
Refractive error measurements after LASIK using the Grand Seiko autorefractor are reliable and agree well with subjective refraction measurements.
The Ohio State University College of Optometry, Columbus, Ohio 43210, USA. mbailey@optometry.osu.edu
Melissa D
MD
Bailey
Michael D
MD
Twa
G Lynn
GL
Mitchell
Deepinder K
DK
Dhaliwal
Lisa A
LA
Jones
Timothy T
TT
McMahon
D000328:Adult; D005123:Eye / Q000473:pathology*; D005260:Female; D006801:Humans; D020731:Keratomileusis, Laser In Situ; D008297:Male; D009885:Ophthalmology / Q000295:instrumentation*; D011184:Postoperative Period; D012029:Refraction, Ocular; D012030:Refractive Errors / Q000175:diagnosis*; D015203:Reproducibility of Results