Abstract
Abstract: :
Purpose: To determine clinical factors that may precede the development of unusually acute cases of infiltrative keratitis (ACIK) during silicone hydrogel extended wear (EW).Method: The ocular, lens fitting and lens performance characteristics of five subjects who experienced ACIK were compared to a group of 28 subjects that had no adverse events for the 15 month period of silicone hydrogel EW prior to the first case of ACIK. In an exploratory analysis, all clinical variables measured at dispensing, 1, 3, 6, 9, 12 and 15 months EW were compared for the two groups of subjects. Statistical analysis was performed using the Mann Whitney exact test. The level of significance was set at p<0.1, given the small sample size. Significant variables will later be entered into a logistic regression to determine predictive factors in these events.Results: There was no difference in age or male:female ratio of the two groups. The ACIK spherical component of the spectacle refraction was lower for the ACIK cases compared to the subject group without adverse events (p<0.05). The ACIK cases exhibited higher bulbar redness levels at baseline, (inferior quadrant, p=0.07), 3MEW (nasal, p=0.01, inferior, p<0.01), 9MEW (nasal , p=0.09), 12MEW (nasal, p<0.01, superior, p=0.02), and in the temporal, superior and inferior quadrants at 15MEW (p<0.05). At1MEW and 9MEW, there was greater corneal staining (extent, type and depth) (inferior cornea at 1MEW and superior cornea at 9MEW) in the eyes of the ACIK cases. The lids of the ACIK cases had higher lid margin erythema (p<0.05), more greasy scales (p<0.05) and overall blepharitis (p<0.1) at baseline, more dry scales and overall blepharitis at 1MEW (p<0.05), more lid margin erythema and overall blepharitis at 3MEW (p<0.05), more overall blepharitis at 6MEW (p<0.05) and more dry scales (p<0.1) and overall blepharitis (p<0.05) at both 12MEW and 15MEW.Conclusion: Higher bulbar redness and signs of blepharitis at baseline and during EW of silicone hydrogel lenses and greater corneal staining during EW may associated with the development of ACIK.
Keywords: 367 contact lens • 369 cornea: clinical science • 437 inflammation