An unexpectedly low Stratus optical coherence tomography false-positive rate in the non-nasal quadrants of Asian eyes: indirect evidence of differing retinal nerve fibre layer thickness profiles according to ethnicity.
OBJECTIVE
To determine the frequency distribution of false-positive Stratus optical coherence tomography (OCT) results of healthy eyes in terms of peripapillary location.


METHODS
One eye of each of 137 healthy Korean subjects was included. The false-positive rates (FPRs) relating to retinal nerve fibre layer (RNFL) thickness parameters were determined.


RESULTS
Of the 12 clock-hour positions, the 2 and 4 o'clock positions showed the highest FPRs of 5.1% and 4.4%, respectively, and 7, 8 and 11 o'clock had the lowest FPRs of 0% at <5% level. At <1% level, 2 and 6 o'clock had an FPR of 0.7%, while the FPR was 0% for all other clock-hours. The FPRs for quadrant thicknesses at <5% level were: 0.7% for temporal; 0% for superior; 5.1% for nasal; and 2.2% for inferior. At <1% level, the inferior showed the highest FPR of 0.7%, and the other three quadrants 0%. According to line graph analysis, the 80-120 test point sections had FPRs of 4.4-6.6%, while the 0-40 and 210-256 sections were 0-0.7% at <5% level. At <1% level, the 40-60, 90-110 and 200-210 sections had 0.7%, 190-200 section 1.5%, and all other sections 0%.


CONCLUSIONS
The FPR for the non-nasal region was much lower than expected at <5% level. Given that the current OCT normative database is based on a largely non-Asian population, these findings suggest that RNFL thickness profiles may differ according to ethnicity.
Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.
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Kim
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Kim
K H
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Park
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Kim
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D016208:Databases, Factual; D005189:False Positive Reactions; D005260:Female; D005901:Glaucoma / Q000175:diagnosis* / Q000208:ethnology; D006801:Humans; D007723:Korea; D008297:Male; D008875:Middle Aged; D010786:Photoreceptor Cells / Q000033:anatomy & histology; D012016:Reference Values; D012160:Retina / Q000033:anatomy & histology*; D041623:Tomography, Optical Coherence / Q000379:methods* / Q000592:standards