The Size, Location, and Clinical Severity of Corneal Infiltrative Events Associated With Contact Lens Wear

Abstract

The purpose of this study is to determine the relationship between the size, location, and clinical severity of corneal infiltrative events (CIEs) associated with contact lens wear. We examined a series of contact lens wearers, presenting consecutively to a large hospital clinic, who had any form of CIE. The severity of the CIE was quantified using a clinical severity matrix based on scores attributed to each of 10 signs and symptoms. The infiltrate was accurately drawn on a schematic diagram of the ocular surface, and from this, we determined its size (i.e., largest dimension) and distance from the limbus. Cartograms were constructed to illustrate the size and location of the corneal infiltrates according to wearing modality and lens type. Useable data pertaining to 111 patients were analyzed. A significant positive correlation was found between the distance of the infiltrate from the limbus versus clinical severity (p = 0.002), but not between the distance of the infiltrate from the limbus versus infiltrate size (p = 0.97). The cartograms revealed a tendency for infiltrates to occur in the superior cornea of patients wearing extended wear silicone hydrogel lenses (p = 0.0002) in the central cornea of patients wearing daily wear hydrogel daily disposable lenses (p = 0.007) and in the peripheral cornea of patients wearing daily wear hydrogel (excluding daily disposable) lenses (p = 0.0006). These data statistically validate the previously held anecdotal notion that CIEs which occur in the peripheral cornea are less clinically severe than those which occur in the central cornea. Consideration of the distribution of CIEs may facilitate a better understanding of the etiology of these events and can serve to alert practitioners as to their likely clinical presentation.