A comparison of conventional and disposable extended wear contact lenses.

The charts of 126 extended wear contact lens patients (65 disposable and 61 conventional extended wear lens users) were reviewed for subjective and objective contact lens problems. We found that the number of complication events per person per year of lens wear was higher for conventional extended lens wearers than for disposable extended wear patients. There was a trend in both groups toward decreased numbers of complications in the second and third years of lens wear. Within each group, we also examined first time lens wearers and patients with a history of contact lens related complications. Both of these subgroups also fared better with disposable lenses, with fewer complication events per year and fewer complications overall. Of the 20 individual signs and symptoms that were analyzed, 13 occurred more frequently among conventional extended wear lens users; this difference was statistically significant for itching, burning and dryness, poor vision, foreign body sensation, torn and lost lenses, giant papillary conjunctivitis, mucus, and superficial punctate keratopathy. Five signs were more frequent among the disposable extended wear lens users, but the difference was not statistically significant. There were no cases of ulcerative keratitis in either group. The average wearing time was 11.2 +/- 5.9 days for conventional extended wear patients and 6.7 +/- 2.3 days in the disposable group. The difference in wearing time between the two groups may have been a factor in the higher complication rate among conventional extended wear lens patients.