Development and evaluation of evidence-based guidelines on contact lens-related microbial keratitis

To assess the response to clinical guidelines based on recent epidemiological studies of contact lens-related microbial keratitis.

Incidence rates for silicone hydrogel extended wear were summarized from recent studies. Risk factors were listed and two key factors identified: overnight wear and poor hygiene accounting for 43% and 33% of risk, respectively. A pre-guidelines, web-based survey was conducted to assess the need for information and level of knowledge on CL-related microbial keratitis (n=162). Comparisons to a post-guidelines survey (n=51) measured whether new information was acquired through an educational brochure posted to the membership.

In the pre- and post-guidelines surveys, 52% (85/162) vs. 43% (22/51, p=0.3) indicated they did not have enough information on CL-related microbial keratitis. The importance attached to risk factors was generally reflective of the magnitude of risk and practitioners made appropriate recommendations about low risk modalities. Hygiene practices were rated as highly important in both surveys (>90%) with increased awareness of handwashing (p=0.03). Overnight wear of hydrogel lenses was considered highly important in 94% (201/213). However, despite evidence to the contrary, only 53% in the pre-guidelines and 58% in the post-guidelines surveys indicated that silicone hydrogel overnight wear was a highly important risk factor.

Research evidence has been disseminated to the BCLA membership and responses gathered via a web survey. There are some areas of disconnect between practitioner opinion, as gauged in this survey, and the evidence from the research, particularly with regards to increased risk with overnight wear.