Abstract
Purpose: :
To examine the relationship between movement of the bulbar conjunctiva during blinking and dryness of the ocular suface, we analyzed the change in superficial conjunctival blood vessel position (BVP) during blinking using a high speed camera.
Methods: :
The dry eye group was comprised of 28 eyes diagnosed by the 2006 Japanese dry eye diagnostic criteria (D group, 32.7 ± 12.6, mean age ± SD, yrs), and the normal group consisted of 30 eyes (N group, 31.4 ± 9.2 yrs). There was no significant difference in the age or sex of the two groups. Using a high speed camera (KEYENCE VW-6000), a tracking point was established on a temporal superficial conjunctival blood vessel 5 mm away from the limbus, and the change in position of the point was measured from the beginning of eyelid closure until it was no longer possible to track movement. In addition, change in BVP was measured by an identical method 30 seconds after administration of 0.1% sodium hyaluronate eye drops used as a lubricant.
Results: :
The average change in BVP in the D group (0.83±0.34 mm) was significantly larger compared with the N group (0.65±0.25 mm) (p=0.037). The change in BVP was more strongly negatively correlated with BUT (tear film breakup time) in the D group (rs= - 0.551, p<0.01) than in the N group (rs = - 0.287, p<0.01). After administration of sodium hyaluronate eye drops, the magnitude of the change in BVP significantly decreased (p<0.01) in both the D group (0.64±0.31 mm) and the N group (0.51±0.21 mm), and there was no significant difference between the two groups.
Conclusions: :
The movement of the bulbar conjunctiva during blinking may be useful as an index of increased friction resulting from dryness of the ocular surface.
Keywords: cornea: tears/tear film/dry eye • conjunctiva • eyelid