In the last decade, we have seen rigid gas permeable (RGP) lenses maintain a roughly 10% share of fits and refits in the United States, with a recent survey of contact lens prescribers ascribing the highest growth potential to scleral lenses.¹ Some of this usage, particularly smaller scleral or mini-scleral lenses, is for refractive error, but a portion of this is for therapeutic use, that is, for the treatment of a disease state.

Here, I discuss the conditions that can benefit from the therapeutic application of scleral lenses, as these lenses protect against an adverse environment, and by virtue of providing a precorneal fluid reservoir, neutralize irregular astigmatism, which affords optimal vision.

Irregular Corneas

It’s now apparent that scleral lenses fill an unmet need in the rehabilitation of keratoconus (KC), when spectacles, soft lenses, and corneal RGP lenses are inadequate for a patient’s visual needs. Additionally, scleral lenses mask irregular astigmatism and decrease higher-order aberrations in patients who have irregular corneas.

Further, scleral lenses have been shown to yield equivalent and faster visual outcomes without the inherent surgical and lifelong risks and the uncertain refractive result of PK, after conventional contact lenses fail.^1,2

Indeed, one can make the point that the only reason for PK in corneal ectasia is axial scarring, which reduces vision. Furthermore, axial scarring cannot be assessed without a scleral lens trial because some of the reduction of vision related to a “scar” may be related to the distortion of the ocular surface rather than the apparent opacity.

Although the decline in PK for KC is typically attributed to the advent of corneal cross-linking, that delay is likely to manifest over many years, suggesting that the increased use of scleral lenses as an alternative to surgery has pushed the rate down.³

Many of these patients can be fitted with commercially available scleral lenses, such as the Jupiter Scleral and Europa Scleral (Visionary Optics), Zenlens, (Bausch + Lomb) AccuLens (Accu Lens), and Onefit Scleral Lens Platform (Blanchard Contact Lenses), to name just a few. Others may benefit from larger, more custom lenses, such as the ocular surface prosthesis offered in PROSE (BostonSight) treatment or the EyePrintPRO (EyePrint Prosthetics).^4,5

Ocular Surface Disease

Scleral lenses are certainly welcome news in the care of patients who have ocular surface disease, particularly those entities for which medical and surgical interventions are inadequate.⁶

• Ocular chronic Graft-versus-Host Disease (cGVHD). This can be considered the poster child for the therapeutic use of scleral contact lenses in ocular surface disease. Ocular cGVHD affects a significant portion of hematopoietic stem cell transplant recipients. In many cases, ocular surface disease symptoms emerge as the patient’s biggest problem in the second year after transplantation when systemic immunosuppression is reduced. Topical and systemic treatment, short of increasing systemic steroid use with all its side effects, does little for cGVHD signs and symptoms. Scleral lenses, on the other hand, have an immediate and striking impact on symptoms and the quality of life for these patients.⁷ (As a brief, yet somewhat-related aside, readers should be aware of the value of bandage soft lenses in ocular cGVHD, as these are easily accessible and familiar to cornea specialists.^8,6) (Figure 1)

• Stevens-Johnson syndrome (SJS). Scleral lenses are also of proven benefit in the management of ocular surface disease related to Stevens-Johnson syndrome.^7,9,10 They have a role in the sub-acute phase, particularly if the patient develops a persistent epithelial defect or ulceration. In the chronic phase, scleral lenses offer the relief of symptoms and support of the ocular surface related to the keratoconjunctivitis that typically occurs in the presence of lid margin keratinization and exposure. (Figure 2)

      

• Persistent epithelial defects, exposure keratitis and neurotrophic keratopathy. Scleral lenses can be used on a continuous-wear basis, with daily disinfection and prophylactic antibiotics, for persistent epithelial defects in the outpatient setting and for exposure related to burns and trauma in the inpatient setting.^11,12 Broader use for keratopathy among patients treated in oculoplastics clinics is described.

Finally, there is a role for long-term use in the setting of neurotrophic keratopathy.¹³ Specifically, children who have hereditary sensory and autonomic neuropathy, in which bilateral corneal opacification progresses rapidly in the first two decades, are particularly good candidates for scleral lenses. Lack of corneal sensation is precisely why such young children can cooperate with lens fitting, daily insertion and removal by their caregivers. Children who have corneal sensation and those highly sensitive due to SJS can be fitted by practitioners who have the appropriate skill and patience.

Scleral lenses can also be used for support of the ocular surface and improvement of vision in limbal stem cell deficiency. Caution is warranted, given that contact lenses are associated with the development of limbal stem cell deficiency! Only peroxide disinfection systems should be used. Close attention must be paid to lens thickness, lens material, and fit to avoid any hypoxic or mechanical stress at the limbus.

As with the other conditions listed above, close follow-up is warranted to monitor for adverse effects, which may appear as progression of disease.

Limitations

Scleral lenses aren’t perfect and may not work for every patient. I have found that the smaller diameter versions, although easier to fit, can be prone to seal-off and suction, with clouding of the fluid reservoir, insult to the epithelial tight junctions and corneal edema. Patients may complain of fogging and reduced vision. Additionally, I have discovered that eyes with aqueous tear deficiency, lid margin abnormalities, or poor blink may be subject to fouling of the front surface of the lens. This clouding of the reservoir and front-surface fouling are limiting factors for scleral lenses in patients who have good vision and non-specific dry eye disease. Further, I have found that eyes that have reduced endothelial cell count resulting from Fuchs’ endothelial dystrophy or previous keratoplasty may do poorly with scleral lenses due to limited endothelial reserve and poor epithelial tight junctions. However, lens modifications, such as tear ventilating channels on the back surface of the lens, or full-thickness fenestrations, may reduce suction and allow access to just enough atmospheric or tear film oxygen for physiologic function of the lens.

An Important Option

Scleral lenses are an important option in the armamentarium of corneal specialists. Continued innovations in material science and manufacture and increased understanding of physiology will increase their utility. To learn more about scleral lenses, I recommend “Scleral lenses: a literature review¹⁴ and “A Guide to Scleral Lens Fitting” (http://commons.pacificu.edu/mono/10/ ). CP

References:

1. Nichols JJ, Starcher LS. Contact Lenses 2019, Contact Lens Spectrum, January 1, 2020 www.clspectrum.com/issues/2020/january-2020/contact-lenses-2019 . Accessed December 7, 2020.
2. DeLoss KS, Fatteh NH, Hood CT. Prosthetic Replacement of the Ocular Surface Ecosystem (PROSE) scleral device compared to keratoplasty for the treatment of corneal ectasia. Am J Ophthalmol. 2014;158:974-82.
3. Koppen C, Kreps EO, Anthonissen L, Van Hoey M, Dhubhghaill SN, Vermeulen L. Scleral Lenses Reduce the Need for Corneal Transplants in Severe Keratoconus. Am J Ophthalmol. 2018;185:43-47.
4. Jeng BH, Farid M, Patel SV, Schwab IR. Corneal Cross-linking for Keratoconus: A Look at the Data, the Food and Drug Administration, and the Future. Ophthalmology. 2016;123(11):2270-72.
5. Stason WB, Razavi M, Jacobs DS, et al. Clinical benefits of the Boston Ocular Surface Prosthesis. Am J Ophthalmol. 2010;149(1):54-61.
6. Schornack MM, Pyle J, Paten SV. Scleral lenses in the management of ocular surface disease. Ophthalmology. 2014;121(7):1398-1405.
7. Jacobs DS, Rosenthal P. Boston scleral lens prosthetic device for treatment of severe dry eye in chronic graft-versus-host disease. Cornea. 2007;26(10):1195-1199.
8. Nguyen MY, Thakrar V, Chan CC. EyePrintPRO therapeutic scleral contact lens: indications and outcomes. Can J Ophthalmol. 2018;53:66-70.
9. Russo PA, Bouchard CS, Galasso JM. Extended-wear silicone hydrogel soft contact lenses in the management of moderate to severe dry eye signs and symptoms secondary to graft-versus-host disease. Eye Contact Lens. 2007;33(3):144-147.
10. Inamoto Y, Sun YC, Flowers ME, et al. Bandage Soft Contact Lenses for Ocular Graft-versus-Host Disease. Biol Blood Marrow Transplant. 2015;21(11):2002-2007.
11. Papakostos TD, Le H, Chodosh J, Jacobs DS. Prosthetic replacement of the ocular surface ecosystem as treatment of ocular surface disease in patients with a history of Stevens-Johnson syndrome/toxic epidermal necrolysis. Ophthalmology. 2015;122(2):248-253.
12. Sotozono C, Ymauchi N, Maeda S. Kinoshita S. Tear exchangeable limbal rigid contact lens for ocular sequelae resulting from Stevens-Johnson syndrome or toxic epidermal necrolysis. Am J Ophthalmol. 2014 Nov;158(5):983-993.
13. Lin A, Patel N, Yoo D, DeMartelaere S, Bouchard C. Management of ocular conditions in the burn unit: thermal and chemical burns and Stevens-Johnson syndrome/toxic epidermal necrolysis. J Burn Care Res. 2011;32(5):547-560.
14. Schornack MM. Scleral lenses: a literature review. Schornack MM. Eye Contact Lens. 2015;41(1):3-11.

 

DR. JACOBS is the director of the Massachusetts Eye and Ear Ocular Surface Imaging Center. Her faculty appointments include Mass Eye & Ear Cornea Service and associate professor of Ophthalmology, part-time, at the Harvard Medical School. She was the president of the Contact Lens Association of Ophthalmologists (2014 to 2016), and spent 15 years as director, Cornea Service, Beth Israel Deaconess Medical Center, in Boston.