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Purpose To estimate the prevalence of patient-reported midday fogging and to identify risk factors for midday fogging. Method A multicenter, cross-sectional study was conducted with an electronic survey that was distributed to scleral lens practitioners. The survey asked them to describe their most recently examined established scleral lens patient. Respondents provided data about patient-reported midday fogging, patient demographic characteristics, indication for lens wear, lens-wearing schedule, lens design, and care products. Results Of the 248 survey respondents who indicated whether their patients had midday fogging, 64 (25.8 %) had patients who self-reported such issues. Midday fogging was not associated with demographic characteristics (age, sex, race/ethnicity), indications for scleral lens wear, mean lens diameter (P = .30), haptic design (P = .29), use of a daily cleaner (P = .12), disinfection/storage solution used (P = .71), or filling solution (P = .65). Patients who reported midday fogging more commonly reported redness or irritation associated with scleral lens wear compared with those who did not experience midday fogging (P = .03). Conclusions Prevalence of midday fogging in this study was similar to previously reported rates. No specific lens design or care product was associated with patient-reported midday fogging. If inflammatory mediators are elevated in the postlens fluid reservoir of patients with midday fogging, as previously described, the redness or irritation associated with scleral lens wear suggests that ocular surface inflammation may be contributing to this phenomenon.

SIGNIFICANCE Scleral lenses (SLs) are increasingly being considered as the initial correction for patients with keratoconus. In this study, keratoconus patients report higher levels of comfort and visual satisfaction with SL compared with corneal gas-permeable lenses (GPs). PURPOSE This study aimed to compare patient satisfaction and care burden associated with GP and SL for the management of keratoconus. METHODS An electronic survey was distributed by the National Keratoconus Foundation from October 2016 to March 2017. Age at diagnosis, initial and current treatment, lens complications, access to care, lens handling time, and annual out-of-pocket treatment costs were collected. Vision, lens comfort, and ease of use satisfaction were rated from 1 to 5. RESULTS A total of 422 responses were received, including 75 bilateral GP and 76 bilateral SL wearers. Scleral lens wearers had greater satisfaction with vision (3.2 ± 1.1 [SL] vs. 2.6 ± 1.1 [GP]; P < .001) and comfort (3.3 ± 1.0 [SL] vs. 2.2 ± 1.2 [GP]; P < .001) but similar ease of use satisfaction in both groups (2.8 ± 1.1 [SL] vs. 2.7 ± 1.1 [GP]; P < .90). Both groups reported issues with cloudy or foggy vision (GP, 63%; SL, 58%) and contact lens discomfort (GP, 77%; SL, 67%). Although GP wearers reported more issues with lens movement or loss (40 [GP] vs. 18% [SL]), they had fewer difficulties with halos (53 vs. 72% [SL]) and lens handling (40%) compared with SL wearers (63%). Gas-permeable lens (48%) and SL (45%) wearers spend 6 to 10 minutes daily handling their lenses. Sixty percent of GP wearers reported annual out-of-pocket cost expenses less than U.S.$1000, whereas only 41% of SL wearers reported the same. CONCLUSIONS Scleral lens wearers with keratoconus report greater satisfaction with vision and comfort than do GP wearers, although both groups reported cloudy vision and lens discomfort.

SIGNIFICANCE As scleral lens wear becomes more common, understanding the impact of these lenses upon ocular physiology is critically important. Studies on the effect of scleral lens wear upon intraocular pressure (IOP) have used different instruments and have reported conflicting results. PURPOSE The purpose of this study was to compare assessment of IOP during scleral lens wear using pneumatonometry and transpalpebral tonometry. METHODS Twenty healthy subjects wore a small-diameter (15.2 mm) and a large-diameter (18.0 mm) scleral lens on the right eye, each for 1 hour in randomized order. IOP was assessed with pneumatonometry and transpalpebral tonometry on both eyes before lens application, immediately after lens application, after 1 hour of lens wear, and immediately after lens removal. Paired t test compared mean IOP in the study eye to the control eye. Repeated-measures ANOVA was performed to take instrumentation, lens diameter, and their interaction into account in an analysis of the change in IOP in the study eye. RESULTS Mean peripheral IOP measured with pneumatonometry was not significantly different from baseline at any subsequent measurement. Measurements with transpalpebral tonometry, however, were significantly different during scleral lens wear immediately after application and after 1 hour of wear with both diameter lenses (P < .005), but were not significantly different after either sized lens was removed. Repeated-measures ANOVA revealed that the instrument used to measure IOP was a significant factor in IOP changes found during lens wear (P ≤ .001). CONCLUSIONS Assessment of IOP during scleral lens wear varies based upon the instrument that is used. Although further studies are clearly needed to further elucidate this issue, clinicians should continue to monitor optic nerve structure and function in scleral lens wearers, as they do in all patients.

Objectives To assess dry eye symptoms associated with different contact lens modalities in patients with keratoconus using a dry eye questionnaire. Methods An online survey was distributed by the National Keratoconus Foundation. The survey asked participants to report demographic characteristics, current optical correction, age at the time of diagnosis of keratoconus, and contact lens history. The 12-item Ocular Surface Disease Index (OSDI) questionnaire was also completed. Data from participants wearing the same contact lens modality bilaterally were analyzed. Results The survey was completed by 197 individuals wearing the same contact lens modality bilaterally. The average age of participants at the time of the survey was 47.2±14.8 years (range: 15-87 years), and the average age at which keratoconus was diagnosed was 26.1±9.9 years (range: 8-55 years). The mean overall OSDI score of all participants was 40.2±22.8 (range: 0-100). There was no difference in the mean OSDI scores based on current contact lens modality type (F=1.79; n=187; P=0.13). Based on an OSDI score of 33 or higher, 90% of participants reported symptoms indicative of dry eye disease. Scleral lens wearers reported less discomfort on the individual items related to windy and low-humidity conditions. Conclusions Individuals with keratoconus, irrespective of contact lens modality, report a high incidence of dry eye symptoms.

OCCUPATIONAL APPLICATIONS Our study examined the influences of visual occlusion on healthy adults during the performance of hand coordination tasks. We found that central vision occlusion, similar ...

Introduction This study was conducted to evaluate the functional performance of the BrainPort V100 device, an FDA-cleared sensory-substitution system, in persons who are profoundly blind (that is, have some or no light perception). Methods This was a prospective, single-arm, multicenter clinical investigation. Participants received 10 hours of device training and were required to use the device in their everyday environments for 1 year. Functional performance measures of object identification, orientation and mobility (O&M), and word identification were assessed at baseline, in post-device training, and at the 3-, 6-, 9-, and 12-month time points. Results Fifty-seven participants completed the study and used the device for 1 year. No device-related serious adverse events were reported, demonstrating that the risks associated with the BrainPort are minimal. Participants performed object recognition (91.2% success rate) and O&M (57.9% success rate) tasks beyond chance level. Discussion This study demonstrates that the BrainPort can be used safely and independently by persons who are blind. Participants with profound blindness can accomplish a set of tasks more successfully by using the BrainPort than without the device. Following initial training, performance on these tasks was maintained or improved over the course of 1 year. Implications for practitioners The BrainPort is a noninvasive and nonsurgical device that heightens functional independence for persons who are blind. The device presents users with more information about their environment than conventional assistive devices, and can enhance independence in performing activities of daily living.

To describe patient-specific outcomes of scleral lens wear utilizing a variety of lens designs across multiple practice settings as reported in an international practitioner survey.An electronic survey was administered to eye care providers who prescribe scleral lenses in which they were asked to describe their most recently examined established scleral lens patient. Data was collected on patient characteristics, lens designs, wearing schedules, care products, and visual and physiological outcomes of lens wear. Descriptive analysis of data was performed.A total of 292 responses were received. Participants represented 26 countries. The most commonly reported indication for scleral lens wear was corneal irregularity (87%) followed by ocular surface disease (8%), refractive error (4%) and 1% with multiple indications. Visual acuity improved from 0.4 ± 0.4 (mean ± SD) to 0.1 ± 0.2 in eyes with corneal irregularity (p 0.001), from 0.3 ± 0.3 to 0.1 ± 0.3 in eyes with ocular surface disease (p 0.001), and from 0.1 ± 0.1 to 0.0± [0.1] in eye with refractive error (p = 0.01). Prior to scleral lens wear, corneal staining was present in 55% of patients; staining was present in only 35% of patients following scleral lens wear. The number of topical ophthalmic drops needed decreased from 1.7 ± 0.9 to 0.8 ± 0.8 in patients with corneal irregularity (p 0.001) and from 3.5 ± 1.7 to 1.1 ± 1.0 in patients with ocular surface disease (p 0.001). The number of drops used by patients with refractive error remained stable, with these patients using an average of 2.0 ± 1.0 drops prior to scleral lens wear and 1.7 ± 1.5 drops following scleral lens wear.Patients with corneal irregularity experienced the greatest improvement in visual acuity, but patients with ocular surface disease and refractive error also achieved better visual acuity with scleral lenses. Ocular surface condition improved in patients with both corneal irregularity and ocular surface disease; patients with ocular surface disease experienced the most dramatic improvement. Patients who wore scleral lenses to correct uncomplicated refractive error did not experience an improvement in signs or symptoms of ocular surface disease.

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.

Objectives To examine the types of contact lenses used as bandage lenses in the postoperative management of patients with Boston type 1 keratoprosthesis (K-Pro). We examined the lens parameters, the number of trial lenses used to achieve successful fit, and lens replacement schedule. The strategies to achieving a successful fit in these complex patients are reviewed. Methods This was a single-center, retrospective chart review of patients who had undergone implantation of the Boston keratoprosthesis in 1 or more eyes from January 2006 to December 2011. Patients included male and female subjects aged 18 years or older who had been fit with bandage contact lenses as part of their postoperative management. Results Twenty-two eyes of 15 patients met the criteria for this review. The age range was 30 to 90 years. There were eight men and seven women. The average number of lenses to achieve a successful fit varied from 1 to 8, with an average of 2.22 trial lenses used per patient. By 6 months after the surgery, 12 K-Pro eyes showed visual acuity of 20/200 or better, with 7 of those eyes attaining better than 20/80 best-corrected Snellen distance acuity. Conclusions Our results show that it is often necessary to use custom contact lenses for K-Pro patients. Management of poor tear film quality, protein deposition, inflammation, lens replacement schedule, and antibiotic resistance are related considerations.

Vision impairments such as age-related macular degeneration (AMD) and glaucoma are among the top risk factors for geriatric falls and falls-related injuries. AMD and glaucoma lead to loss of the central and peripheral visual fields, respectively. This study utilized a custom contact lens model to occlude the peripheral or central visual fields in healthy adults, offering a novel within-subject approach to improve our understanding of the etiology of balance impairments that may lead to an increased fall risk in patients with visual field loss. Two dynamic posturography tests, including an adapted version of the Sensory Organization Test and a virtual reality environment with the visual scene moving sinusoidally, were used to evaluate standing balance. Balance stability was quantified by displacement and time-normalized path length of the center of pressure. Nine young and eleven older healthy adults wore visual field occluding contact lenses during posturography assessments to compare the effects of acute central and peripheral visual field occlusion. The results found that visual field occlusion had greater impact on older adults than young adults, specifically when proprioceptive cues are unreliable. Furthermore, the results suggest that both central and peripheral visions are important in postural control; however, peripheral vision may be more sensitive to movement in the environment.

OBJECTIVE. We sought to determine whether intensive low vision rehabilitation would confer any functional improvement in a sample of blind adults using the BrainPort artificial vision device. METHOD. Eighteen adults ages 28–69 yr (n = 10 men and n = 8 women) who had light perception only or worse vision bilaterally spent up to 6 hr per day for 1 wk undergoing structured rehabilitation interventions. The functional outcomes of object identification and word recognition were tested at baseline and after rehabilitation training. RESULTS. At baseline, participants were unable to complete the two functional assessments. After participation in the 1-wk training protocol, participants were able to use the BrainPort device to complete the two tasks with moderate success. CONCLUSION. Without training, participants were not able to perform above chance level using the BrainPort device. As artificial vision technologies become available, occupational therapy practitioners can play a key role in clients’ success or failure in using these devices.

Purpose: Neuronal reorganization after blindness is of critical interest because it has implications for the rational prescription of artificial vision devices. The purpose of this study was to distinguish the microstructural differences between perinatally blind (PB), acquired blind (AB), and normally sighted controls (SCs) and relate these differences to performance on functional tasks using a sensory substitution device (BrainPort). Methods: We enrolled 52 subjects (PB n = 11; AB n = 35; SC n = 6). All subjects spent 15 h undergoing BrainPort device training. Outcomes of light perception, motion, direction, temporal resolution, grating, and acuity were tested at baseline and after training. Twenty-six of the subjects were scanned with a three Tesla MRI scanner for diffusion tensor imaging (DTI), and with a positron emission tomography (PET) scanner for mapping regional brain glucose consumption during sensory substitution function. Non-parametric models were used to analyze fractional anisotropy (FA; a DTI measure of microstructural integrity) of the brain via region-of-interest (ROI) analysis and tract-based spatial statistics (TBSS). Results: At baseline, all subjects performed all tasks at chance level. After training, light perception, time resolution, location and grating acuity tasks improved significantly for all subject groups. ROI and TBSS analyses of FA maps show areas of statistically significant differences (p ≤ 0.025) in the bilateral optic radiations and some visual association connections between all three groups. No relationship was found between FA and functional performance with the BrainPort. Discussion: All subjects showed performance improvements using the BrainPort irrespective of nature and duration of blindness. Definite brain areas with significant microstructural integrity changes exist among PB, AB, and NC, and these variations are most pronounced in the visual pathways. However, the use of sensory substitution devices is feasible irrespective of microstructural integrity of the primary visual pathways between the eye and the brain. Therefore, tongue based devices devices may be usable for a broad array of non-sighted patients.

We describe an indoor, portable, standardized course that can be used to evaluate obstacle avoidance in persons who have ultralow vision. Six sighted controls and 36 completely blind but otherwise healthy adult male (n=29) and female (n=13) subjects (age range 19-85 years), were enrolled in one of three studies involving testing of the BrainPort sensory substitution device. Subjects were asked to navigate the course prior to, and after, BrainPort training. They completed a total of 837 course runs in two different locations. Means and standard deviations were calculated across control types, courses, lights, and visits. We used a linear mixed effects model to compare different categories in the PPWS (percent preferred walking speed) and error percent data to show that the course iterations were properly designed. The course is relatively inexpensive, simple to administer, and has been shown to be a feasible way to test mobility function. Data analysis demonstrates that for the outcome of percent error as well as for percentage preferred walking speed, that each of the three courses is different, and that within each level, each of the three iterations are equal. This allows for randomization of the courses during administration. Abbreviations: preferred walking speed (PWS) course speed (CS) percentage preferred walking speed (PPWS)

We have observed dramatic effects of tactile tongue stimulation on nystagmus eye movements in patients with acquired blindness, and we report these results. Six adult subjects (3 subjects with light perception or worse vision and 3 normal subjects) were included in this study. Causes of blindness included traumatic explosion, anterior ischemic optic neuropathy, and central retinal artery occlusion. Duration of blindness was 15, 3 and 1.5 years, respectively. A video eye tracking system (Eyelink 1000) was used to record eye movements. The eye movement recording (EMR) was repeated four times in a span of 20 min. Two of the EMRs were performed without tongue stimulation and two with tongue stimulation in randomized order. A tongue stimulus was applied to the surface of the tongue using a Brainport device that produces an electrical tactile stimulus. The nystagmus waveform characteristics and frequency were analyzed. We found that all blind subjects showed continuous jerk nystagmus with slow and quick phases, mainly in horizontal plane in their primary eye positions. The recorded nystagmus waveforms were jerk with linear velocity slow phases. When the tongue stimulus was applied, the frequency of nystagmus was significantly reduced by 47, 40, and 11%, and relative amplitude was reduced by 43, 45, and 6% for three blind subjects, respectively. In conclusion, we think our results that tongue stimulation influences nystagmus eye movements support a link between non-visual sensory input and ocular motor activity.