Corneal epithelial bullae after short-term wear of small diameter scleral lenses

Complications of scleral lens wear are not well documented or understood. While multiple studies focus on oxygen transmission during scleral lens wear and associated corneal swelling, little is known about the effects of varying scleral lens fitting relationships, especially when there is corneal interaction. Scleral lenses, by convention, are designed to completely clear the corneal surface and rest on the conjunctival and scleral tissue. However, some designs maximize oxygen transmission by reducing the lens diameter, thickness, and recommended corneal clearance.While the modifications increase oxygen transmission in any scleral lens design, they also distribute the lens mass closer to the limbus and make visualization of corneal clearance, especially narrow in the limbal region, more difficult. The sequelae from mechanical interaction between scleral lenses and the ocular surface, in particular the cornea, remain uncertain. This case series will describe corneal epithelial bullae, molding, and epithelial erosions as unintended scleral lens complications. These corneal changes corresponded to areas of contact lens-corneal bearing confirmed utilizing a combined scanning laser ophthalmoscopy (SLO) and anterior segment OCT. This case series will discuss epithelial bullae detection, their etiology, and suggestions for application of this information into scleral lens fitting protocols.