Fluorescein dye disappearance test in patients with different degrees of epiphora

To assess the diagnostic efficacy of a modification of the fluorescein dye disappearance test (DDT) in patients with different degrees of epiphora.

DDT was performed by instilling a drop of 2% fluorescein in the eye. Schirmer tear test strips were placed in the lower conjunctival fornix, after 3 and 10 minutes. The colour dilution on the strips was compared to a scale with known standards and the most closely comparable colour dilution was chosen and recorded as the visual scale test (VST) grade of the strip. The grey-scale value (GV) of each strip was calculated by computer image analysis. The control group comprised 44 patients, mean age 44.8 years (SD 7.5, range 30-60). There were 13 patients in group 1 with moderate epiphora; mean age was 44.2 years (SD 9.5, range 30-60). There were 17 patients in group 2 with severe epiphora; mean age was 48.3 years (SD 7.7, range 37- 60).

VST and GV differed significantly between controls and group 1 patients at 3 minutes (p=0.002, p=0.001), and between controls and group 2 patients at 3 minutes (p<0.001, p<0.001). There was no difference between groups 1 and 2 patients in VST and GV at 3 minutes. The differences were highly significant between controls and group 1 at 10 minutes (p=0.001, p=0.007), and between controls and group 2 at 10 minutes (p<0.001, p<0.001). The differences in GV and VST between groups 1 and 2 were significant at 10 minutes (p=0.026, p=0.018).

This modified DDT permits identification of different degrees of epiphora in a non-invasive manner, it can therefore be used to evaluate the outcome of different treatment strategies.