Influence of Soft Contact lens on Tear Excretion Measured with lacrimal Scintillography

ABSTRACT

In order to evaluate the influence of soft contact lens(SCL) on the tear turnover rate in the conjunctival sac with SCL, this study was performed with lacrimal scintillography. Two determinations were carried out in the same eye the first determination was carried out in both eyes without SCL(control group) and the second determination was carried out in both eyes after adaptation to the SCL from 4 hours to 8 hours only in the left eye(study group). In the results, there was no statistical difference of the fractional turnover rate of the tear between both eyes without SCL. In left eyes, the fractional tunover rate of the study group was significantly lower than that of the control group, because the accumulation of the Technetium 99m sodium pertechnetate in the SCL. In right eyes, there was no statistical difference of the fractional turnover rate of the tear between the control group and the study group. This result may be derived from 'fatigue block' and/or the decreased sensitivity of the cornea fitted with SCL.