Post-Penetrating Keratoplasty Assessment of Endothelial Function With a Scleral Lens Challenge.

ABSTRACT: Patients who have undergone penetrating keratoplasty may have corneal edema because of endothelial cell dysfunction. Scleral lens wear may exacerbate edema, particularly if lens fit is suboptimal. Distinguishing between edema because of inherent endothelial cell dysfunction and swelling because of scleral lens-related hypoxia can be challenging. It is necessary, however, to identify the most likely cause of increased corneal thickness to determine whether the patient simply needs refitting for a different lens design or needs additional surgical intervention. This case report describes the utility of corneal tomographic imaging before and after scleral lens wear both to estimate endothelial cell function and to direct decisions when designing a scleral lens for a post-transplant eye.

Patient-Reported Dry Eye Treatment and Burden of Care.

OBJECTIVES: Dry eye is a common condition that can decrease the quality of life. This survey-based study of persons with dry eye investigated self-reported treatments (initial, current), out-of-pocket expenses, time spent on self-management, sources of care, and sources of information about their condition. METHODS: Online dry eye newsletters and support groups were emailed a link to an electronic survey asking members to participate. Survey respondents were not required to answer every question. RESULTS: In total, 639 persons with self-reported dry eye responded (86% women, 14% men [n=623]; mean ± SD age, 55 ± 14 years [n=595]). Artificial tears were the most reported intervention (76% initially, 71% currently). The median (interquartile range) out-of-pocket treatment cost annually was $500 ($200-$1,320 [n=506]). In addition, 55% (n=544) estimated 5 to 20 min daily on self-management; 22% spent an hour or more. Ophthalmologists provided most dry eye care (67%, n=520). Only 48% (n=524) reported that their primary source of dry eye information came from their eye care clinician. CONCLUSIONS: Artificial tears are the primary treatment for dry eye. Ophthalmologists provide most dry eye care, but half of patients report that their eye care provider is not their primary source of information. Almost one fourth of patients spend an hour or more daily on treatments.

Survey-Based Estimation of Corneal Complications Associated with Scleral Lens Wear.

ABSTRACT: The benefits of scleral lens (SL) wear have been described in cross-sectional and retrospective studies; however, the frequency of complications associated with SL wear has not, to the best of our knowledge, been determined. From a survey of SL practitioners, we estimated the period prevalence over 1 year of corneal complications that required SL wearers to discontinue lens wear. In a sample of 72,605 wearers, SL wear was discontinued for the following complications: corneal edema, 1.2%; corneal neovascularization, 0.53%; microbial keratitis, 0.45%; and limbal stem cell deficiency, 0.20%. This study design allowed for calculation of period prevalence of these complications rather than complication incidence rates. Information presented in this report may be useful in clinical decision-making and for future study design.

Current Trends in Scleral Lens Prescription, Management, and Evaluation.

OBJECTIVES: To report current trends in scleral contact lens prescription and management, including lens designs prescribed, care products recommended, and procedures performed during routine scleral lens (SL) evaluation. METHODS: An online survey was designed by the Scleral Lenses in Current Ophthalmic Practice Evaluation study team and administered to eye care practitioners attending a specialty contact lens meeting. The survey was available from November 8, 2019, through March 31, 2020. Participants' demographic data were collected, along with information on lens diameters, landing zone (LZ) designs, recommended care products, and components of routine SL evaluation. RESULTS: In total, 715 participants responded to at least one of the survey items of interest. Most lenses prescribed (63%) were 16 mm or more in diameter. Lenses with toric LZs were the most frequently prescribed (48%), followed by spherical (40%), quadrant-specific (8%), and impression-based or image-based designs (3%). Most participants (61%) recommended hydrogen peroxide products for lens care. Nonpreserved saline in a single-use vial was most frequently recommended to fill the bowl of the lens before application. Intraocular pressure was measured during SL evaluation by 45% of participants; 38% of participants routinely measured corneal thickness. CONCLUSIONS: Practitioners increasingly are prescribing SLs with advanced LZ designs. Most practitioners recommend hydrogen peroxide-based disinfection systems and single-use vials of nonpreserved saline for lens care and application. Because differences in components of routine SL evaluations were reported, clinicians may benefit from reaching a consensus on essential components of SL evaluation.

Trends in Scleral Lens Fitting Practices: 2020 Scleral Lenses in Current Ophthalmic Practice Evaluation Survey.

OBJECTIVES: To explore trends in demographic characteristics of scleral lens (SL) practitioners and primary indications for SL fitting over 5 years. METHODS: An online survey similar to the 2015 Scleral Lenses in Current Ophthalmic Practice Evaluation (SCOPE) study was designed and administered from November 8, 2019, through March 31, 2020, to attendees at two international contact lens meetings, members of the Scleral Lens Education Society, and participants in the 2015 SCOPE study. Practitioners reporting at least five completed SL fits were included in the analysis. RESULTS: Of 922 respondents, 777 had fit at least five SLs: 63% from the United States (59 other countries were represented), findings similar to the 2015 survey, in which 799 respondents (72%) were US-based and 49 from other countries. Most practitioners were in community practice (76%) than academic practice (24%). In 2015, 64% were in community practice and 36% in academic practice. A median of 84% of SLs were fit for corneal irregularity, 10% for ocular surface disease, and 2% for uncomplicated refractive error. In comparison, the 2015 indications were 74%, 16%, and 10%, respectively. The median number of fits completed per practitioner was 100 (range, 5-10,000; mean [SD] 284 [717]; n=752). In 2015, the median was 36 (range, 5-3,600; mean [SD] 125 [299]; n=678). CONCLUSIONS: The number of experienced SL practitioners is increasing, as is international representation. Most practitioners practice in community rather than academic settings. SLs continue to be primarily prescribed for corneal irregularity and are rarely used solely for correction of refractive error.

Microbial Keratitis Associated With Penetrating Keratoplasty and Scleral Lens Wear: A Case Series.

OBJECTIVES: To report on microbial keratitis (MK) in three scleral lens (SL) wearers who had undergone penetrating keratoplasty (PKP). METHODS: This retrospective case series describes 3 cases of MK in patients who wore SLs after PKP. RESULTS: All three patients wore SLs for visual rehabilitation for corneal irregularity induced by PKP; all three also had concurrent ocular surface disease (keratoconjunctivitis sicca and corneal exposure). Cultures identified the causative organism in two patients, and septated hyphae suggestive of fungal infection were identified in tissue removed during therapeutic PKP in the third patient. All three patients were receiving either topical or systemic immunosuppressive therapy before the infection developed. CONCLUSIONS: Scleral lenses are often used to manage complex ocular disease, which can make it difficult to determine the precise cause of complications that arise after wearing the lenses. Multiple factors, including SL wear, may have contributed to the initial development of MK in the three patients in this case series. Patients who wear SLs after PKP should be monitored closely.

Tear Exchange, Intraocular Pressure, and Wear Characteristics of Quadrant-specific Versus Spherical Haptic Scleral Lenses.

OBJECTIVES: To compare scleral lenses (SLs) with a quadrant-specific (study lens) or a spherical (habitual lens) landing zone in a crossover study. METHODS: Seven participants (eight eyes) wore each of two lenses for 2 weeks before measurements. We measured visual acuity, contrast sensitivity, intraocular pressure (IOP), fluid reservoir clearance, corneal thickness, tear exchange, and lens experience. Variables were compared between lenses and before and after 2 hr of wear. RESULTS: The visual acuity was not different between the study lens, 0.12 logarithm of the minimum angle of resolution (logMAR), and habitual lens, 0.18 logMAR (median, P = 1.0). Contrast sensitivity was 1.3% under the study lens and 1.6% under the habitual lens ( P = 0.94). IOP did not change after 2 hr of wear for either lens (study lens, P = 0.33 and habitual lens, P = 0.74), and corneal thickness did not change during wear of either lens ( P = 0.44). The fluorescein concentration under the study lens did not change after 2 hr (99% of initial concentration; P = 0.84) but decreased to 46% of initial concentration under the habitual lens ( P = 0.008). Lens comfort was slightly better with the study lens (5.0 vs. 4.0, respectively; P = 0.05). CONCLUSIONS: SLs with spherical or quadrant-specific landing zones provide good vision and do not affect IOP or corneal thickness. However, tear exchange is greater under spherical lenses than under quadrant-specific lenses. The quadrant-specific lens provides greater patient comfort.

Quadrant-Specific Changes in Corneal and Tear Fluid Reservoir Thickness for After 2 Hours of Wear.

OBJECTIVE: To measure corneal swelling and thickness of the tear fluid reservoir (TFR) after wearing scleral lenses (SLs). METHODS: Thirty-five participants had 1 eye fitted with each of three SLs (15.0-mm Jupiter, 18.2-mm Jupiter, and 18.0-mm Digiform). Scheimpflug images were obtained before wear, after application, after 2 hr of wear, and after removal. Initial and final TFR thickness and corneal thickness were measured in the central cornea and 3 mm from the center in the superior, inferior, temporal, and nasal quadrants. RESULTS: Corneal thickness increased with wear, but no between-lens differences were observed in the superior (P=0.09), inferior (P=0.38), or temporal (P=0.53) quadrants. The greatest change in central and nasal cornea thickness was with the 15.0-mm SL (P<0.001). All areas showed settling, with no between-lens differences. Greater final TFR thickness was noted for the superior and nasal quadrants with the 18.0-mm SL (P<0.001), and less final TFR thickness was noted in the inferior (P<0.001) and temporal (P<0.001) quadrants with the 15.0-mm SL. Corneal thickness was not associated with the final TFR thickness. CONCLUSIONS: The greatest corneal swelling was observed in the inferior quadrant with the 15.0-mm SL, although this lens had the least TFR thickness inferiorly. TFR thickness alone did not account for observed corneal swelling.

Clinical Outcomes of Scleral Lens Fitting with a Data-driven, Quadrant-specific Design: Multicenter Review.

SIGNIFICANCE: Alignment of the scleral lens haptic with the anterior ocular surface is of critical importance when fitting scleral lenses. The concept of leveraging big-data analysis to drive lens design is explored in this study. This retrospective study evaluated fitting outcomes of a data-driven, quadrant-specific scleral lens design and found that most patients (76%) were successfully fit with this design. PURPOSE: The purpose of this study was to evaluate clinical outcomes with a data-driven, quadrant-specific scleral lens design compared with traditional lens designs. METHODS: For this multicenter retrospective observational study, A REDCap (Research Electronic Data Capture) survey was distributed to scleral lens practitioners who participated in ß testing of a data-driven, quadrant-specific scleral lens design (study lens) between June 1, 2016, and January 31, 2017. Descriptive data were collected, and patient-reported outcomes, visual acuity, and lens design outcomes achieved with the study lens were described. RESULTS: Seventy-five patients (85 eyes) were fit with the study lens design between June 2016 and January 2017. Mean patient age was 47 years (range, 17 to 77 years). Forty-six were male, and 29 were female. Seventy-six eyes (89%) were fit for corneal irregularity, whereas nine eyes (11%) were fit for management of ocular surface disease. Compared with habitual correction, 22% more eyes achieved 20/20 or better, and 21% more eyes achieved 20/40 or better. There was also a 60% decrease in the need for midday removal with the study lens. An average of two lenses were manufactured per eye to complete the fitting process. CONCLUSIONS: Using a data-driven, quadrant-specific scleral lens resulted in visual improvement, a reduced need for midday removal, and an average of two lenses needed to complete the fitting process. Longer-term clinical outcomes and the use of big-data analysis to inform scleral lens design should be further explored.

Region-Specific Changes in Postlens Fluid Reservoir Depth Beneath Small-Diameter Scleral Lenses Over 2 Hours.

OBJECTIVES: Scleral lenses settle on the eye with time, and the depth of the postlens fluid reservoir decreases. We measured changes in central, superior, inferior, temporal, and nasal clearance beneath a small-diameter scleral lens after 2 hr of lens wear in healthy eyes. METHODS: Thirty-one participants (age, mean±SD, 29±7 years) with no history of eye disease or scleral lens wear were fitted with a 15-mm scleral lens in 1 eye. Scheimpflug images were acquired by a camera system within 5 min of lens placement and again after 2 hr of continuous lens wear. The central cornea was located in both horizontal and vertical meridians, and lens clearance was measured at that point. Lens clearance was also measured 2 mm superior, inferior, nasal, and temporal to the center of the cornea. RESULTS: After 2 hr of lens wear, central clearance was reduced 46% (mean [SD], from 227 [77] to 122 [61] µm; P<0.001). Superior clearance was reduced 48% (from 168 [62] to 87 [61] µm); inferior clearance, 54% (from 241 [82] to 111 [55] µm); temporal clearance, 45% (from 224 [79] to 124 [74] µm); and nasal clearance, 52% (from 166 [73] to 80 [49] µm) (P<0.001 for all). Statistically significant decreases in clearance were noted at all points assessed after 2 hr of lens wear. CONCLUSIONS: Fluid reservoir depth beneath small-diameter scleral lenses decreased nearly 50% after 2 hr of lens wear in normal eyes.

Changes in Optical Density of Postlens Fluid Reservoir During 2 Hours of Scleral Lens Wear.

OBJECTIVES: Debris accumulation in the postlens fluid reservoir during scleral lens wear is clinically observed. We evaluated a method to quantify increases in turbidity of the postlens fluid reservoir by assessing changes in optical density of the fluid over time and compared these changes during 2 hr of scleral lens wear using three different lens designs. METHODS: Thirty-five patients (age, mean [SD], 29 [7] years) with no history of eye disease were enrolled in the study. Participants were fit with a 15.0-, 18.0-, and 18.2-mm scleral lens on one randomly selected eye during the enrollment examination. During each of three subsequent visits, one of three lenses selected during enrollment was placed on the eye. Scheimpflug images were acquired within 5 min of lens placement and at 20-min intervals for the ensuing 2 hr. Fluid reservoir optical density was assessed using Pentacam (Oculus Inc) analysis software. RESULTS: Increases in fluid reservoir optical density were significant between each time interval with all lenses until 100 min. No significant increases in fluid reservoir optical density were noted with the 15.0- and 18.0-mm lenses between 100 and 120 min; fluid reservoir optical density increased with the 18.2-mm lens between 100 and 120 min. Optical density increased by 105% (15.0-mm lens) and 117% (18.0- and 18.2-mm lenses) at 2 hr. CONCLUSIONS: Optical density of the postlens fluid reservoir can be quantified during scleral lens wear. During 2 hr of wear, fluid reservoir optical density doubled with all lens designs evaluated.

Scleral Lenses in the Management of Corneal Irregularity and Ocular Surface Disease.

PURPOSE: To describe current practice patterns regarding the use of scleral lens therapy in the management of corneal irregularity and ocular surface disease among eye care providers who fit scleral lenses. METHODS: The Scleral Lenses in Current Ophthalmic Practice: an Evaluation (SCOPE) study group conducted an electronic survey of eye care providers from January 15 to March 31, 2015. Respondents ranked management options for corneal irregularity in the order in which they would generally consider their use. Respondents also ranked options for the management of ocular surface disease in the order in which they would use each of the treatments. Results for each option were analyzed as percentage first-place ranking; percentage first-, second-, or third-place ranking; and mean rank score. RESULTS: Survey responses were obtained from 723 providers who had fit 5 or more scleral lenses. Of these respondents, 629 ranked options for management of corneal irregularity and 612 ranked options for management of ocular surface disease. Corneal rigid gas-permeable lenses were the first option for management of corneal irregularity for 44% of respondents, and scleral lenses were the first option for 34% of respondents. Lubricant drops were the first therapeutic recommendation for ocular surface disease for 84% of respondents, and scleral lenses were ranked first by 6% of respondents. CONCLUSION: Scleral lenses rank second only to corneal rigid gas-permeable lenses for management of corneal irregularity. Scleral lenses are generally considered after other medical intervention and before surgery for the management of ocular surface disease.

Demographic Characteristics and Prescribing Patterns of Scleral Lens Fitters: The SCOPE Study.

OBJECTIVES: This study reports demographic characteristics of scleral lens providers and indications for scleral lens prescription as assessed by a worldwide online survey. METHODS: The Scleral Lenses in Current Ophthalmic Practice: an Evaluation (SCOPE) study group designed the online survey regarding current scleral lens prescription and management practices. The Mayo Clinic Survey Research Center administered the survey, which was open from January 15 to March 31, 2015. Data from 989 responses were collated by the Survey Research Center and deidentified before analysis. Responses of individuals who had fit at least five patients with scleral lenses were analyzed in detail. RESULTS: Most lens fitters were men (61%, n=800). Of survey respondents, 29% were 25 to 34 years; 22%, 35 to 44 years; 22%, 45 to 54 years; and 26%, more than 55 years (n=806). For 29% of all respondents, professional training was completed between 2009 and 2014 (n=804). Most (54%) fit their first patient between 2010 and 2015, with the earliest lens fit reported in 1956 (n=634). Most respondents (63%) worked primarily in private, group, or retail practice (n=811). Scleral lenses were most often prescribed for corneal irregularity (74%), followed by ocular surface disease (16%) and uncomplicated refractive error (10%) (n=673). CONCLUSIONS: Eye care providers of all ages are fitting scleral lenses. The number of individuals who fit this lens modality has increased during the past decade. Scleral lenses are being fit by providers in a wide range of practice settings. Most scleral lenses are prescribed for corneal irregularity.

Scleral Lens Prescription and Management Practices: The SCOPE Study.

OBJECTIVES: To assess current scleral lens prescription and management practices by conducting an international online survey of eye care providers. METHODS: The SCOPE (Scleral Lenses in Current Ophthalmic Practice: an Evaluation) study group designed and administered an online survey regarding current scleral lens prescription and management practices. The survey was open from January 15 to March 31, 2015, and generated 723 responses from individuals who had fit at least 5 patients with scleral lenses. RESULTS: Respondents (n=663) prescribed scleral lenses that ranged from 15 to 17 mm in diameter (65%), smaller than 15 mm (18%), and larger than 18 mm (17%). More than 50 lens designs were identified. Average daily wearing time of 11.8 hr was consistent across 651 respondents, and 475/651 (73%) recommended midday removal on some, most, or all days. Most respondents recommended nonpreserved saline to fill the bowl of the lens before application (single-use vials, 392/653 [60%]; bottled products, 372/653 [57%]). A hydrogen peroxide-based disinfection system was the most commonly recommended care product (397/651 [61%]). CONCLUSIONS: A reasonable degree of consensus exists regarding some aspects of scleral lens prescription and management (average lens diameter, daily wearing time, and use of nonpreserved products for lens application). Further study is needed to develop evidence-based guidelines for scleral lens prescription and management.

Intraocular Pressure After 2 Hours of Small-Diameter Scleral Lens Wear.

OBJECTIVES: Compression of episcleral veins or deformation of tissue in the Schlemm's canal beneath the landing zone of scleral lenses could elevate intraocular pressure (IOP). We examined the effect of 2 hr of small-diameter scleral lens wear on IOP. METHODS: Twenty-nine participants, 29 ± 6 years old (mean ± SD) who experienced no history of eye disease or scleral lens wear, were included in the study. Each participant was fitted with a 15-mm Jupiter scleral lens on one eye (study eye). Intraocular pressure was measured in both eyes by pneumatonometry centrally on the cornea and peripherally on the sclera. The lens was then placed on one eye and was worn for 2 hr. Intraocular pressure was remeasured immediately after lens placement, at 1 and 2 hr of lens wear, and immediately after lens removal. Intraocular pressure after removal of the scleral lens was compared with IOP before placing the lens and to IOP in the control eye using paired t tests. RESULTS: Immediately after removing the scleral lens, mean central IOP in the study eye (13.9 ± 3.1 mm Hg) was not different from mean central IOP in the control eye (13.5 ± 2.2 mm Hg, P = 0.4) or in the same eye before lens wear (13.6 ± 1.9 mm Hg, P = 0.6). There were also no differences in IOP measured peripherally at 2 hr of lens wear (P = 0.8). CONCLUSIONS: Neophyte scleral lens wear of a 15-mm scleral lens for 2 hr does not increase IOP in healthy eyes.

Scleral lenses: a literature review.

OBJECTIVE: To present a comprehensive review of current and historical literature on scleral lenses. METHODS: A comprehensive search of several databases from each database's earliest inception to May 23, 2014 was conducted by an experienced librarian with input from the author to locate articles related to scleral lens design, fabrication, prescription, and management. RESULTS: A total of 899 references were identified, 184 of which were directly related to scleral lenses. References of interest were organized by date, topic, and study design. Most of articles published before 1983 presented lens design and fabrication techniques or indications for scleral lens therapy. Case reviews published after 1983 identified major indications for scleral lenses (corneal ectasia, ocular surface disease, and refractive error) and visual and functional outcomes of scleral lens wear. Statistically significant improvements in visual acuity, vision-related quality of life, and ocular surface integrity were reported. Reviews of ocular and systemic conditions suggested that comprehensive management strategies for these conditions could include scleral lenses. Early work investigating scleral lens fitting characteristics, optical qualities, and potential physiological impact on anterior ocular structures have been published in the past 5 years. CONCLUSIONS: Indications for scleral lens wear are well-established. Developing areas of research on the physiologic impact of scleral lens wear on the ocular surface, the use of technology to improve scleral lens vision and fit, and the impact of these devices on the quality of life should further enhance our understanding of scleral lenses in the future.

Ocular Graft-Versus-Host Disease: A Review.

Hematopoietic stem cell transplantation is important in the management of several lymphoproliferative and bone marrow disorders. Graft-versus-host disease (GVHD) involves inflammatory manifestations that arise after transplant and can affect many organs. Ocular manifestations of GVHD are common, and eye care providers must understand this disease entity. The ocular surface is most commonly involved, but GVHD can affect all parts of the eye. Ocular GVHD can be relapsing and remitting, can decrease quality of life, and can be challenging to diagnose and adequately treat. The diagnostic criteria for and grading of ocular GVHD continue to evolve. This review aims to summarize current definitions, clinical findings, diagnostic criteria, and management of ocular GVHD. The care of patients with ocular GVHD requires a multidisciplinary approach.

Scleral lenses in the management of ocular surface disease.

PURPOSE: To describe the management of ocular surface disease with commercially available scleral lenses. DESIGN: Retrospective case series at a tertiary referral center. PARTICIPANTS: A total of 212 patients (346 eyes) who were evaluated for scleral lens therapy for the management of ocular surface disease between June 1, 2006, and November 30, 2011. METHODS: Retrospective review of medical records and analysis of a survey mailed to all patients who completed the scleral lens fitting process to evaluate the long-term success of scleral lens therapy in the management of ocular surface disease. MAIN OUTCOME MEASURES: Therapeutic outcome of scleral lens therapy, improvement in visual acuity with scleral lenses, indications for scleral lens wear, and efficiency of fitting process. RESULTS: Of the 212 subjects, 115 (188 eyes) successfully completed the scleral lens fitting process, and therapeutic goals (improved comfort, ocular surface protection, or resolution of keratopathy) were achieved in all but 2 of these subjects. Visual acuity improved with scleral lens wear, from 0.32 ± 0.37 logarithm of the minimal angle of resolution (logMAR) (mean ± standard deviation; Snellen equivalent, 20/42) with habitual correction to 0.12 ± 0.19 logMAR (Snellen equivalent, 20/26) with scleral lenses (P<0.001). The most common indications for scleral lens therapy were undifferentiated ocular surface disease, exposure keratopathy, and neurotrophic keratopathy. Subjects had attempted an average of 3.2 (range, 0-8) other forms of intervention before scleral lens wear. Scleral lens fitting was completed in an average of 3 visits (range, 2-6), with an average of 1.4 lenses/eye (range, 1-4). Three patients experienced complications during scleral lens wear that resolved without loss of visual acuity, enabling resumption of scleral lens wear. CONCLUSIONS: Commercially available scleral lenses can be successfully used in the management of moderate to severe ocular surface disease. The scleral lens fitting process can be completed efficiently for most eyes by using diagnostic trial lenses. In addition to protecting the ocular surface, scleral lenses improve visual acuity in patients whose surface disease has compromised vision.

Anatomical and physiological considerations in scleral lens wear: Intraocular pressure.

Intraocular pressure (IOP) is maintained through complex and interrelated systems which control aqueous production and drainage, and it has been suggested that scleral lens (SL) wear may disrupt these vital homeostatic processes. This review provides an overview of anatomical and physiological processes that control IOP, identifies potential effects of SLs on these regulatory mechanisms, and examines studies that have attempted to quantify the effect of SLs on IOP. Lack of access to the cornea during SL wear makes accurate assessment of IOP challenging; therefore, a range of different assessment techniques and instruments have been employed to quantify IOP during and following SL wear. Some studies have evaluated IOP using standard techniques prior to lens application and following lens removal, or through a large central fenestration. Other studies have utilised instruments that facilitate assessment of IOP on the peripheral cornea or conjunctiva overlying the sclera (e.g. Schiotz, transpalpebral, and pneumatonometry). Two studies have recently evaluated changes in optic nerve structure during SL wear. Conflicting results have been reported on this topic, much of which examines changes in IOP in healthy subjects over limited periods of time. Currently, only a few studies have reported on long-term effects of SL wear on IOP in habitual SL wearers (after lens removal). Future research in this area must not only consider the fact that ocular conditions treated with SLs may potentially alter corneal biomechanical properties which can influence IOP, but also that these properties may be further altered by SL wear. Monitoring other risk factors for glaucoma (permanent alterations in optic nerve physiology, visual field defects) could provide a more comprehensive assessment of potentially increased risk of glaucomatous optic neuropathy due to SL wear. Ongoing clinical assessment of optic nerve structure and function is advisable in patients at risk for glaucoma who require SLs.

Graduating optometry student perceptions of their scleral lens fitting knowledge.

Although optometric programs have incorporated scleral lens (SL) education into their curricula, actual student experiences with SL fitting varies widely. This survey study describes the SL fitting and training experiences of graduating optometry students in US schools and colleges. Participants (323) were fourth-year students preparing to graduate in 2020 (19% response rate). Students appeared to have insufficient SL fitting practice, the median number of SL evaluations completed before graduation was 5 (range 0-110) and 63% reported less than 10 fits. Students with an interest in fitting SLs may wish to pursue additional training opportunities, such as residency, to acquire further experience before achieving sufficient proficiency with SLs.