WHILE SCLERAL LENSES (SLs) have gained popularity for managing various ocular conditions, their primary indication remains corneal irregularities (Schornack et al, 2023). A recent survey reported a significant shift in preference by clinicians for managing corneal irregularities, with 42% now opting for SLs as the treatment of choice (Shorter et al, 2023). This article will discuss some of the recent advances in SL usage.

SLs can play a crucial role in managing moderate to severe dry eye disease (DED) and associated conditions by alleviating discomfort, reducing reliance on lubricants, and enhancing visual acuity (VA) (Alipour et al, 2012; Jacobs et al, 2021). Unfortunately, some DED patients continue to experience discomfort caused by lens surface deposits and debris (Visser et al, 2007).

A 90% water polyethylene glycol (PEG)-based polymer coating has recently shown promise in enhancing the comfort of rigid and soft contact lens wear and has been applied to SLs (Mickles et al, 2021). The surface of the contact lens is chemically bonded with this polymer mixture coating, resulting in a permanent wetting surface (Mickles et al, 2021).

This coating effectively separates the lens material from the ocular surface and tear film with a clear hydrophilic shell, resulting in improved surface wettability, increased tear breakup time, reduced deposition of proteins and lipids, and improved lubricity, comfort, symptoms, tear film stability, ocular surface signs, and VA (Mickles et al, 2021).

Patients who have DED are also more prone to experiencing midday fogging (McKinney et al, 2017), which can result in decreased VA (Rathi et al, 2012) and potential corneal punctate staining (Pecego et al, 2012). Recent research has linked higher levels of nonpolar lipids to increased fogging during SL wear (Walker et al, 2023). Given that changes to lipid composition in the tears are found in diseases such as meibomian gland dysfunction, analysis of lipids as part of managing midday fogging may be needed in the future.

Moderate changes in intraocular pressure (IOP) might occur in some individuals who wear SLs, although the studies investigating this link in the literature demonstrate variation (Fadel and Kramer, 2019). A new approach proposed to evaluate IOP while patients wear SLs is to measure the Bruch’s membrane opening-minimum rim width (BMO-MRW) at the optic nerve head (Samaha and Michaud, 2021).

Using this approach, researchers observed a decrease in BMO-MRW measurements with SL wear, estimated to correspond to an increase in IOP of approximately 5 mmHg. Further research, including investigations involving different disease populations, is necessary to gain a better understanding of the relationship between SLs and IOP, and whether increased vigilance in monitoring for signs of glaucoma in at-risk populations wearing SLs is necessary.

SLs can come in various designs, including prolate and oblate back optic zone with spherical, toric, and quadrant-specific designs in the limbal area and peripheral back surface (Barnett et al, 2021). Additionally, elliptical lenses are available to improve lens fit (Fadel 2018), while the inclusion of fenestrations (Fadel and Ezekiel, 2020) and channels (Carrasquillo and Byrne, 2018) serves to reduce suction and prevent corneal edema. More advanced customization, including the development of specific free-form lens designs using techniques such as scleral profilometry or impression, are becoming available (Barnett et al, 2021).

Notably, advancements in SL optics encompass the incorporation of prisms for addressing binocular issues and effectively managing higher-order aberrations (HOAs) (Vincent and Fadel, 2019). In cases in which HOA optics or advanced and decentered ectasias are present, the SL optic zone can be intentionally decentered to optimize vision and lens fitting and stability. These lens designs have improved the availability of high-quality customized SLs, making fittings that historically have been challenging more straightforward and widely available. CLS

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