Thursday, September 10, 2009

Abstract: Predicting dry eye in new contact lens wearers

The cynic in me (which incidentally seems to be working overtime this morning while catching up on medline) is leaping ahead to anticipate what doctors might do with results like these. Put all patients who fit the risk parameters on Restasis before they start wearing contacts, to maximize their early success in contacts? (Down, boy, down.)

A novel method to predict the dry eye symptoms in new contact lens wearers.
Optom Vis Sci. 2009 Sep;86(9):E1042-50.
Pult H, Murphy PJ, Purslow C.
School of Optometry and Vision Sciences, Contact Lens and Anterior Eye Research (CLAER) Unit, Cardiff University, Wales, United Kingdom. ovr@heiko-pult.de
PURPOSE: Lid wiper epitheliopathy (LWE) and lid parallel conjunctival folds (LIPCOF) give moderate prediction levels for dryness symptoms in experienced contact lens (CL) wearers. This study investigated whether a combination of LWE and LIPCOF plus other tear film tests and subjective evaluation before contact lens fitting was better able to predict CL-induced dry eye (CLIDE) symptoms.

METHODS: Tear meniscus height, non-invasive break-up time (NIBUT), ocular hyperaemia, LIPCOF, phenol red thread test, corneal and conjunctival staining, and LWE of the right eye of 33 new soft CL wearers (12 males, 21 females, median age = 30.5 years; range = 19 to 44) were assessed in a prospective 2-mo longitudinal study. Symptoms were evaluated by the Ocular Surface Disease Index (OSDI) and subjects were grouped according to their response in the Contact Lens Dry Eye Questionnaire (CLDEQ) during the study (20 symptomatic and 13 asymptomatic). The subjects were fitted with vifilcon A and senofilcon A lenses for a 2-week period, consecutively.

RESULTS: Limbal hyperaemia (repeated measures analysis of variance; p < 0.05) and LWE (Friedman; p < 0.004) increased significantly during the study but not LIPCOF (p > or = 0.318; temporal, nasal, and Sum), bulbar hyperaemia (p = 0.432), staining (p > or = 0.060), OSDI (p = 0.126), or CLDEQ (p = 0.317, kappa = 0.279). Limbal hyperaemia significantly decreased in senofilcon A lenses. Wearing comfort among symptomatics was significantly better with senofilcon A (p = 0.005). At the enrolment visit, the subjects who became symptomatic exhibited significantly decreased NIBUT and increased LIPCOF and OSDI (range, p < 0.027). The best test combination to predict CLIDE (logistic regression analyses) was LIPCOF Sum plus NIBUT and OSDI, (positive predictive value = 87% and accuracy = 91%).

CONCLUSIONS: LIPCOF, NIBUT, and OSDI are significant discriminators for CLIDE in new CL wearers compared with hyperaemia, tear meniscus height, phenol red thread test, staining, and LWE. The best test combination is NIBUT plus LIPCOF Sum and OSDI (named the Contact-Lens-Predicting-Test).

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