Reported Scleral Lens Complications May Guide Clinical Decision Making

Corneal edema and neovascularization, microbial keratitis, and limbal stem cell deficiency are complications that may lead to discontinuation of scleral lens wear, according to a survey published in Eye & Contact Lens. Among these complications, microbial keratitis incidence is higher among individuals who wear scleral lenses compared with those who wear rigid corneal or soft contact lenses, according to the report. 

Researchers surveyed 639 contact lens practitioners who evaluated 72,605 scleral lens wearers between November 2019 and March 2020. Clinicians estimated the number of patients who discontinued scleral lens use due to corneal edema, corneal neovascularization, microbial keratitis, or limbal stem cell deficiency.  

Corneal edema was the most common survey-related condition for discontinuing scleral lens wear (n=869; 1.2%), followed by corneal neovascularization (n=385; 0.53%), microbial keratitis (n=325; 0.45%), and limbal stem cell deficiency (n=135; 0.20%).

No differences in prevalence were noted between new and established practitioners for any of the complications, according to the report. Clinicians who worked in a community setting reported higher percentages of patients with microbial keratitis and corneal edema compared with clinicians who worked in an academic setting. Clinicians who practiced in the US reported significantly lower percentages of all 4 complications compared with clinicians who practiced elsewhere (microbial keratitis: 0.38% vs 0.60%; corneal neovascularization: 0.33% vs 0.95%; corneal edema: 1.10% vs 1.41%; limbal stem cell deficiency: 0.12% vs 0.32%; P <.001 for all). 

The investigators estimate microbial keratitis incidence in scleral lens wearers to be 45 cases per 10,000 wearers per year. This value is higher than incidence rates reported from other studies for rigid corneal lens (1.2/10,000 wearers/year), soft contact lens (1.9/10,000 wearers/year) and overnight soft contact lens wear (19.5/10,000 wearers/year), according to the report.

“[T]his survey-based study [provides] an estimate of the frequency with which corneal complications may occur in patients who wear [scleral lenses],” according to the researchers. “It also suggests that, whereas the percentage of patients who experienced [scleral lens]-related complications is low, the risk of [microbial keratitis] is greater than for other types of lenses. This information may help practitioners and patients better assess the risks and benefits of [scleral lens] wear and could provide preliminary data for calculation of the sample size needed for formal investigations of the incidence of complications with this lens modality.”

Study limitations include the potential for recall bias, variations in contact lens practice among practitioners, and failure to determine disease severities.