THE INTERNATIONAL FORUM for Scleral Lens Research (IFSLR) remains a unique assembly in the field of scleral lenses by limiting its focus to sharing and discussing research related to scleral lenses. In this program, the authors of evidence-based literature present on important and related issues, and an equal amount of time is spent discussing the points addressed in these presentations.

The discussions are conducted by practitioners and researchers active in this specialized field and attending this annual forum, which preceded—and is in collaboration with—the Global Specialty Lens Symposium in Las Vegas. This year’s approximately 100 attendees represented a great blend of academics, clinical practitioners, and industry-affiliated people, both on location and remotely connected.

The 2023 IFSLR addressed three important issues: new instrumentation and technology, therapeutics applications for scleral lens wearers, and scleral lens management of special populations. Here we summarize the findings and discussions featured at IFSLR 2023.

SESSION I: NEW INSTRUMENTATION AND TECHNOLOGY

The resurgence in scleral lens prescribing over the past decade has sparked the development of imaging technology that allows us to better understand anterior ocular contour and create lens designs to better align with the surface of the eye (Figure 1). The first session of the 2023 IFSLR meeting was devoted to describing the use of technology in scleral lens fitting.

Pure descriptive data can be derived from anterior surface imaging technology; this data can help us to select an appropriate initial lens design and assess the fit of a scleral lens on the eye. Melanie Frogozo, OD, summarized anterior imaging technology and described how it is used in research and practice.¹ She reported that scleral lenses with toric landing zone designs exhibit minimal rotation if the difference between steep and flat meridians is at least 200 microns; quadrant-specific designs may be most appropriate for eyes in which the sagittal height difference between highest or lowest points is at least 300 to 400 microns, particularly if no regular periodicity between highest and lowest points is observed.

Next, Stephanie Tran, OD, described the use of high-resolution anterior segment optical coherence tomography (AS-OCT) to precisely measure central, paracentral, and limbal clearance in multiple meridians with single-image acquisition.² She suggested that this technology could simplify both clinical lens evaluations and research on scleral lens fitting relationships.

The other three speakers in the first session described outcomes of image- and impression-based scleral lens fitting. Hannah Yoon, OD, presented a summary of the fitting process for eight patients (13 eyes) with ocular surface disease using a tomographer. Mean time needed to acquire a scan was approximately 10 minutes, and the first lens ordered was dispensed for seven of the 13 eyes. The mean number of lenses needed to complete the fit was 2.14 (right eyes) and 2.11 (left eyes), and the mean number of visits required was 2.88; these values are lower than those found in previous studies describing these aspects of the fitting process.^3-6

William Skoog, OD, also reported on CSP-guided scleral lens fitting for six patients (12 eyes) with moderate-to-severe keratoconus (KC). The number of scans required per eye to fabricate an initial lens ranged from two to seven, and 25% of initial lenses ordered were dispensed.

Finally, Amy Nau, OD, summarized the findings of a multicenter retrospective review of impression-based lens fitting that described using impression-based lenses in 44 patients (70 eyes, 44 that have corneal irregularity and 26 that have ocular surface disease).⁷ Of note, 39% of these eyes had undergone at least one surgical procedure, and 56% of patients had unsuccessfully attempted to wear other scleral lens designs.

Improvements in visual acuity were noted in 32 eyes with impression-based lenses compared to habitual correction, and percentages of eyes achieving 20/20 and 20/40 or better also increased with impression-based lenses. An average of 1.3 impressions per eye were obtained. Although initial impressions of 16 eyes were rejected by the laboratory, no patients who had discontinued use of habitual scleral lenses three or more days prior to impression acquisition required subsequent impressions. The mean number of lenses ordered for each eye during the fitting process was 2.1, and the fitting process required an average of four visits per patient.

While these studies suggest that utilization of technology may improve efficiency of the fitting process, suboptimal fitting relationships may still be observed with image- or impression-based lenses. Using this technology does not eliminate the need for careful evaluation of lens fit on the eye. Practitioners must still understand how to manipulate lens parameters to optimize visual and physiological outcomes.

SESSION II: THERAPEUTICS AND SOLUTIONS

The second session of the IFSLR was dedicated to research surrounding the solutions used with scleral lenses and the impact of having a fluid reservoir over the cornea during scleral lens wear. Gloria Chiu, OD, provided the keynote address and presented a variety of related research projects from past years that looked into the sterility of application solutions.

She started by clarifying the established precedent, filling scleral lenses with non-preserved solutions only, and outlined the current U.S. Food and Drug Administration (FDA) approval status of the solutions available in the U.S. She noted that most patients use some form of preservative-free saline solution to fill the scleral lens bowl prior to application. The first study her group performed investigated the growth of bacteria on swabs taken from open bottles of sterile saline that were FDA approved for use in scleral lenses in 2021.⁸ On swabs taken from unused bottles of the saline, no bacterial growth was observed after one, two, seven, 30, and 63 days after opening and incubating.

In a second arm of the study, the researchers inoculated the same sterile saline solution with 11 different bacteria strains and one yeast strain and found that although the bacteria and yeast survived, there was no proliferation of the microorganisms in the saline (i.e., it was bacteriostatic). Lastly, they cultured the bottles and handling devices (plungers) used by 35 scleral lens wearers and found more than 20 different microorganisms.⁹ There were no severe infections found in any of these cases and, although two patients did experience a bacterial conjunctivitis, neither patient had a positive culture reading. To our knowledge, this important work is the only published safety data on the use of these solutions as application solutions; therefore, studies testing the bacterial growth and safety of other FDA-approved solutions are indicated.

The next two speakers in Session II both focused on neovascularization on corneas that were fitted with scleral lenses. First Jenn Liao, OD, shared a published case series of patients who showed successful regression of corneal vascularization when using scleral lenses. These patients had Stevens-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) with scleral lenses. Dr. Liao reminded the audience that ocular pathology is present in the majority of SJS (69% to 81%) and TEN (50% to 67%) patients,^10,11 mostly in the form of dry eye syndrome due to damage to the lacrimal gland and mucosal tissues.^12-14

She presented two cases, one female with SJS and one male with TEN, who were fitted with scleral lenses with back-surface channels that were intended to improve tear exchange and reduce suction.¹⁵ In both patients, the corneal opacification improved and the neovascularization regressed. Overall, this case series highlighted cases of ocular surface disease and corneal opacification that improved with scleral lens wear, resulting in reduced inflammation and increased quality of vision.

The final speaker discussed one of the potential corneal sequelae observed when there is vascularization of the cornea in a patient wearing scleral lenses. Amanda Crum, OD, presented a case report of a man wearing scleral lenses who had an interesting complication arise. This 77-year-old male patient had congenital aniridia, limbal stem cell deficiency (LSCD), and open-angle glaucoma (OAG) and was taking several topical medications (dorzolamide 2% b.i.d., latanoprost 0.005% q.h.s., lifitegrast 5% b.i.d., and artificial tears).¹⁶ Prior to being fitted with scleral lenses, the patient presented with circumlimbal corneal vascularization with branches toward the central cornea. He used an FDA-approved sterile saline to apply the lenses, and experienced intracorneal hemorrhaging after initiating scleral lens wear (Figure 2). 

This patient had glaucoma and was taking a rho kinase inhibitor that reportedly causes conjunctival hemorrhages as a side effect.¹⁷ This case report sparked an interesting discussion, and other attendees reported having seen intracorneal hemorrhages in patients wearing scleral lenses. It was agreed by most that the force of the suction created by removing scleral lenses would be sufficient to cause a hemorrhage of the leaky vascularized vessels in the cornea, although this has never been investigated in the literature.

SESSION III: SCLERAL LENSES IN SPECIAL POPULATIONS

The third session started with the keynote address by Karen Carrasquillo, OD, PhD, discussing the management of traumatic lid ptosis in a pediatric patient, which was successfully treated using scleral lenses.¹⁸ The patient was a 9-year-old boy who had suffered blunt trauma to his left eye, resulting in ptosis and corneal exposure. Despite undergoing several surgical interventions to correct the ptosis, including levator muscle resection and frontalis sling surgery, the patient had no improvement. Thus, the scleral lens was considered as a possible solution and was fitted to the patient’s left eye, resulting in a total central clearance of 1100μm (1.1mm), with the weight distributed over the increased surface area of a 19mm-diameter lens.

One potential concern when fitting patients with a scleral lens for ptosis management is hypoxic corneal stress due to the increased sagittal depth. In this case, the patient’s cornea was able to tolerate this scleral lens fit without any adverse effects. His eye showed clearing of corneal opacities over time, indicating good long-term physiological function of the cornea.

As a result of the treatment, the ptosis was corrected and the corneal exposure was resolved, with the patient’s visual acuity improving from 20/60 to 20/30. Dr. Carrasquillo and her co-authors noted that a scleral lens is a viable option for a pediatric patient who has traumatic lid ptosis, particularly when traditional surgical interventions have failed. They recommend this treatment modality as an option for similar patients for whom traditional surgical interventions have failed, as it can provide excellent visual and functional outcomes with minimal risk and a high degree of patient satisfaction.

S. Barry Eiden, OD, discussed the results of a review of classic and current studies on the frequency of KC, which showed that KC is more widespread than previously believed. While older studies indicated a prevalence of around 1 in 2,000 individuals,¹⁹ newer, more sensitive diagnostic technologies have found frequencies as high as 1 in 375²⁰ or higher.²¹ Discrepancies between studies can be attributed to differences in populations evaluated, including age group, ethnicity, and geographic location, as well as differences in diagnostic criteria and technology used.

Dr. Eiden reported that an ongoing pediatric frequency study has found similarly high frequencies of suspected and confirmed KC in the pediatric population when using corneal Scheimpflug tomography analysis, although the final data is not yet published. The panelists discussed changes in clinical practices based on the increased frequency of KC and the need for affordable advanced technology.

Another presentation by Boris Severinsky, OD, focused on using scleral lenses in pediatric patients who have irregular corneas, including those who have pediatric KC, penetrating ocular trauma, post-pediatric keratoplasty, and various ocular surface diseases. The study included patients 15 years old or younger fitted with scleral lenses for visual rehabilitation and ocular surface protection²² (Figure 3). 

This study found that scleral lens use was beneficial in patients who have advanced KC and traumatic corneal scarring and obviated the need for penetrating keratoplasty in some cases. The challenges associated with fitting and training did not preclude long-term wear in most patients. The authors emphasized the importance of visual rehabilitation and ocular surface protection as the primary goals of scleral lens fitting in pediatric patients.

Christine Sindt, OD, discussed the successful clinical application of scleral lenses in special populations with a wide variety of ocular pathologies, including lid hyperkeratinization, scleral keratinization, LSCD, granulomas, symblepharon, a variety of congenital anomalies, microcornea, megalocornea, blebs, patch grafts, and neurotrophic disease. Throughout the many case discussions, Dr. Sindt reminded the audience to manage the entire patient and emphasized the need for out-of-the box thinking to help these children and their families. One creative story that she shared was of a patient’s mother who was using eyelid tape to help hold her daughter’s ptotic eyelids open along with the scleral lens.

Her discussions focused on how to communicate with and manage these specialty patients on an individual basis—and also pointed out that many specialty patients are very sick beyond their ocular condition. This final session reminded the audience of the powerful impact that SLs can provide for special populations.

CONCLUSIONS

Collectively, the presentations at the sixth annual IFSLR were a resounding success. New and improved technologies facilitate the prescribing of scleral lenses for eyes previously not manageable with scleral lenses. The IFSLR meeting also highlighted population groups that particularly benefit from wearing these lenses. The lively discussions followings the presentations were welcomed by all.

The seventh annual IFSLR will be held on Jan. 17, 2024, prior to the commencement of GSLS 2024 in Las Vegas. CLS

Acknowledgment: The authors would like to acknowledge the scleral lens researchers and clinicians who presented at the sixth annual IFSLR and provided content for this article. Support for the sixth IFSLR was provided by CooperVision, Blanchard Contact Lens, and Bausch Health, and we appreciate the educational support from our media partners, BroadcastMed and the Global Specialty Lens Symposium, as well as our educational partner, The Scleral Lens Education Society.

References

1. Rojas-Viñuela J, Frogozo MJ, Piñero DP. What we know about the scleral profile and its impact on contact lens fitting. Clin Exp Optom. 2022 Jul 11:1-14.
2. Tran S, Roberts CJ, Mahmoud A, Pisano S, Mundy C. Novel High-Resolution Imaging Using ANTERION Optical Coherence Tomography to Assess Fluid Reservoir Change in Scleral Lens Periphery. Eye Cont Lens. 2022 Nov 1;48:466-470.
3. Pecego M, Barnett M, Mannis MJ, Durbin-Johnson B. Jupiter Scleral Lenses: the UC Davis Eye Center experience. Eye Cont Lens. 2012 May;38:179-182.
4. Schornack M, Patel S. Scleral lenses in the management of keratoconus. Eye Cont Lens. 2010 Jan;36:39-44.
5. Schornack MM, Pyle J, Patel SV. Scleral lenses in the management of ocular surface disease. Ophthalmol. 2014 Jul;121:1398-1405.
6. Harthan J, Nau CB, Barr J, et al. Scleral Lens Prescription and Management Practices: The SCOPE study. Eye Cont Lens. 2018 Sep;44 Suppl 1:S228-S232.
7. Nau A, Shorter ES, Harthan JS, Fogt JS, Nau CB, Schornack M. Multicenter review of impression-based scleral devices. Cont Lens Ant Eye. 2021 Oct;44:101380.
8. Seo W, Chiu GB, She RC. Bacteriostatic Effect of Multidose Preservative-free Buffered Saline Used in Scleral Lens Wear. Optom Vis Sci. 2020 Mar;97:162-168.
9. Jeong M, Lee K, She R, Chiu G. Microbiological Evaluation of Opened Saline Bottles for Scleral Lens Use and Hygiene Habits of Scleral Lens Patients. Optom Vis Sci. 2021 Mar 1;98:250-257.
10. Power W, Ghoraishi M, Merayo-Lloves J, Neves RA, Foster SC. Analysis of the acute ophthalmic manifestations of the erythema multiforme/Stevens-Johnson Syndrome/toxic epidermal necrolysis disease spectrum. Ophthalmology. 1995 Nov;102:1669-1676.
11. Chang YS, Huang FC, Tseng SH, Hsu CK, Ho CL, Sheu HM. Erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis: acute ocular manifestations, causes, and management. Cornea. 2007 Feb;26:123-129.
12. Papakostas TD, Le HG, Chodosh J, Jacobs DS. Prosthetic replacement of the ocular surface ecosystem as treatment for ocular surface disease in patients with a history of Stevens–Johnson Syndrome/Toxic Epidermal Necrolysis. Ophthalmology. 2015 Feb;122:248-253.
13. Shanbhag SS, Shah S, Singh M, Bahuguna C, Donthineni PR, Basu S. Lid-Related Keratopathy in Stevens-Johnson Syndrome: Natural Course and Impact of Therapeutic Interventions in Children and Adults. Am J Ophthalmol. 2020 Nov;219:357-365.
14. Kohanim S, Palioura S, Saeed HN, et al. Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis--A Comprehensive Review and Guide to Therapy. Ocul Surf. 2016 Jan;14:2-19.
15. Liao J, Asghari B, Carrasquillo KG. Regression of corneal opacity and neovascularization in Stevens-Johnson syndrome and Toxic Epidermal Necrolysis with the use of prosthetic replacement of the ocular surface ecosystem (PROSE) treatment. Am J Ophthalmol. 2022 Apr 14;26:101520.
16. Crum AR, Srikumaran D. Case Report: Intracorneal Hemorrhages Seen with Scleral Contact Lens Wear and Netarsudil Therapy. Optom Vis Sci. 2022 Apr 1;99:400-404.
17. Batra M, Gupta S, Nair AB, et al. Netarsudil: A new ophthalmic drug in the treatment of chronic primary open angle glaucoma and ocular hypertension. Eur J Ophthalmol. 2021 Sep;31:2237-2244.
18. Phillis K, Brocks D, Carrasquillo KG. Case Report: Use of Prosthetic Replacement of the Ocular Surface Ecosystem Treatment of Traumatic Lid Ptosis in a Pediatric Patient. Optom Vis Sci. 2020 Dec;97:1029-1033.
19. Kennedy R, Bourne W, Dyer J. A 48-year clinical and epidemiological study of keratoconus. Am J Ophthalmol. 1986 Mar 15;101:267-273.
20. Godefrooij DA, de Wit GA, Uiterwaal CS, Imhof SM, Wisse RPL. Age-specific Incidence and Prevalence of Keratoconus: A Nationwide Registration Study. Am J Ophthalmol. 2017 Mar;175:169-172.
21. Millodot M, Shneor E, Albou S, Atlani E, Gordon-Shaag A. Prevalence and associated factors of keratoconus in Jerusalem: A cross-sectional study. Ophthalmic Epidemiol. 2011 Apr;18:91-97.
22. Severinsky B, Lenhart P. Scleral contact lenses in the pediatric population—Indications and outcomes. Cont Lens Ant Eye. 2022 Jun;45:101452.