This includes those with meibomian gland dysfunction (MGD), ocular rosacea, atopic conditions, graft-versus-host disease, Stevens-Johnson syndrome, Sjögren’s syndrome and other severe ocular surface diseases or filamentary keratitis. ![]() Poor tear film quality and stability, lens surface deposits, eyelid disease, allergies, environmental factors and medications can all impede successful contact lens wear. Patients with certain ocular surface diseases are especially at risk for poor surface wettability. 9-11 A contact angle of zero degrees is a completely wettable surface. Small contact angles are associated with an increased ability of the tears to spread over the surface of a contact lens, leading to a more stable tear film. This angle determines the ability of moisture to spread. The contact angle is the angle formed when a drop of liquid is placed on a surface. It is determined by the wetting angle or contact angle. Wettability refers to how easily a liquid spreads over the surface of a contact lens. Understanding the risk factors and underlying mechanisms at play can help you better understand why a patient is struggling with wettability, fogging or both. This article discusses the causes of these two frustrating complications in scleral lens wear-and how you can combat them in your practice. 4-6 Debris accumulation between the scleral lens and cornea can cause lens fogging either rapidly after insertion (sometimes even during the diagnostic lens fitting) or more slowly, worsening throughout the day. 3Īlso, minimal tear exchange exists during scleral lens wear, causing the potential for fogging in the post-lens fluid reservoir. This common issue can cause suboptimal or “cloudy” vision, diminished lens comfort and increased chair time and cost for both the patient and practitioner. 2įor many scleral lens wearers, the fit may be pristine, the patient may report excellent vision and comfort and handling may be smooth, but poor anterior lens surface wetting hampers comfortable long-term wear ( Figure 1). ![]() 1 Although these lenses are problem solvers that can correct for anything from irregular astigmatism and severe ocular surface disease to refractive error and mild-to-moderate dry eye disease, they also present some unique challenges. In recent years, scleral lens popularity has grown tremendously, with fits and refits up to 16% in 2017 compared with 13% in 2016.
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