TY - JOUR
T1 - Effect of Corneal Drying on Optical Coherence Tomography
AU - Stein, Daniel M.
AU - Wollstein, Gadi
AU - Ishikawa, Hiroshi
AU - Hertzmark, Ellen
AU - Noecker, Robert J.
AU - Schuman, Joel S.
N1 - Funding Information:
Supported in part by the National Institutes of Health, Bethesda, Maryland (grant nos.: R01-EY013178-6, P30-EY008098); The Eye and Ear Foundation, Pittsburgh, Pennsylvania; and an unrestricted grant from Research to Prevent Blindness, Inc., New York, New York.
PY - 2006/6
Y1 - 2006/6
N2 - Purpose: To determine the effect of corneal drying on the outcome of optical coherence tomography (OCT). Design: Cohort study. Participants: Seventeen normal participants (mean age, 39±12 years). Methods: Subjects underwent a series of peripapillary circular StratusOCT scans (version 3.0; Carl Zeiss Meditec, Inc., Dublin, CA) in a randomly selected eye. Baseline scan sets were acquired, and thereafter, blinking was prevented by taping the eyelid. Eyelid taping was immediately followed by 6 to 8 serial scan sets, each separated by 20 seconds. After removing the eyelid tape, 3 additional scans were acquired at 1, 2, and 4 minutes of blinking freely. Main Outcome Measures: The analyzed outcome measures were scan quality as defined by signal-to-noise ratio (SNR) and signal strength (SS) provided by the built-in OCT software and mean nerve fiber layer (NFL) thickness. Results: Significant reductions in SNR, SS, and NFL were noted at each scanning point in the drying phase (for each, P<0.015, paired t test) except for NFL thickness measurements acquired at 140 and 160 seconds. The reduction in NFL thickness exceeded the 95% confidence limit of the reported reproducibility error of StratusOCT after 15 seconds of corneal drying. After 1 and 2 minutes of blinking freely, there was still a significant reduction in NFL thickness compared with the baseline value, which was no longer evident at the 4-minute scan. Conclusions: Corneal dryness affects OCT scan quality and measured NFL thickness after a short exposure time. It is recommended to instruct those who are scanned to blink frequently or to instill artificial tears.
AB - Purpose: To determine the effect of corneal drying on the outcome of optical coherence tomography (OCT). Design: Cohort study. Participants: Seventeen normal participants (mean age, 39±12 years). Methods: Subjects underwent a series of peripapillary circular StratusOCT scans (version 3.0; Carl Zeiss Meditec, Inc., Dublin, CA) in a randomly selected eye. Baseline scan sets were acquired, and thereafter, blinking was prevented by taping the eyelid. Eyelid taping was immediately followed by 6 to 8 serial scan sets, each separated by 20 seconds. After removing the eyelid tape, 3 additional scans were acquired at 1, 2, and 4 minutes of blinking freely. Main Outcome Measures: The analyzed outcome measures were scan quality as defined by signal-to-noise ratio (SNR) and signal strength (SS) provided by the built-in OCT software and mean nerve fiber layer (NFL) thickness. Results: Significant reductions in SNR, SS, and NFL were noted at each scanning point in the drying phase (for each, P<0.015, paired t test) except for NFL thickness measurements acquired at 140 and 160 seconds. The reduction in NFL thickness exceeded the 95% confidence limit of the reported reproducibility error of StratusOCT after 15 seconds of corneal drying. After 1 and 2 minutes of blinking freely, there was still a significant reduction in NFL thickness compared with the baseline value, which was no longer evident at the 4-minute scan. Conclusions: Corneal dryness affects OCT scan quality and measured NFL thickness after a short exposure time. It is recommended to instruct those who are scanned to blink frequently or to instill artificial tears.
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U2 - 10.1016/j.ophtha.2006.02.018
DO - 10.1016/j.ophtha.2006.02.018
M3 - Article
C2 - 16751039
AN - SCOPUS:33744520373
SN - 0161-6420
VL - 113
SP - 985
EP - 991
JO - Ophthalmology
JF - Ophthalmology
IS - 6
ER -