Abstract
Purpose::
To determine upper and lower tear menisci on contact lenses using real time optical coherence tomography (OCT).
Methods::
Both eyes of 20 adapted contact lens wearers were imaged when they wore two types of silicone hydrogel lenses, PureVision (balafilcon A, Bausch & Lomb) on one eye and Acuvue Advance (galyfilcon A,Vistakon) on the other eye. The height, curvature and area of upper and lower tear menisci were obtained before, immediately and 20 minutes after lens wear in two consecutive days.
Results::
There were no significant differences of all measured parameters between lenses (ANOVA, F(3, 57) = 0.20, P=0.89) and visits (ANOVA, F(3, 57) = 0.88, P=0.46). Upper tear meniscus heights (UTMH) were 297±48 (Mean ± SD mm) and 301±47 with PureVision and Acuvue, respectively at lens insertion. Lower tear meniscus heights (LTMH) were 317±62 and 310±92 with PureVision and Acuvue, respectively at lens insertion. The menisci around both eyelids immediately after lens insertion were significantly greater than that before lens wear (post hoc, P<0.005). UTMH at lens insertion (averaged, 299±39) was greater than baseline (268±36) and LTMH at lens insertion (314±69) was greater than baseline (266±57). Recovery of tear menisci to baseline 20 minutes after wearing lenses was found. Variables of tear menisci were strongly and significantly correlated (P<0.05).
Conclusions::
It is feasible to use OCT in the measurement of both upper and lower tear menisci on contact lenses in situ. This study was supported by a research grant from Bausch & Lomb.
Keywords: contact lens • clinical research methodology • cornea: tears/tear film/dry eye