Median Snellen Acuity Research Articles

Design of Smart Head–Mounted Display Technology: A Convergent Mixed-Methods Study

Introduction: The purpose of this study was to characterize functional impairments and human factor considerations that affect perceptions and preferences for head-mounted display (HMD) technology for adults with low vision and chronic eye disease. Methods: Through a convergent mixed-methods design, participants with visual impairments (age-related macular degeneration, diabetic retinopathy, glaucoma, or retinitis pigmentosa) were recruited. Participants completed the Impact of Vision Impairment (IVI) questionnaire, used commercially available HMDs (eSight, NuEyes, and Epson Moverio), and were interviewed. The IVI was used to identify groups with low, moderate, and high vision–related quality of life (VRQOL). Transcribed interviews were analyzed using a thematic approach. The survey and qualitative findings were integrated using mixed-methods joint display analysis. Results: Twenty-one participants were enrolled (mean age of 58.2 years, 57% male, median Snellen acuity of 20/40 [range: 20/20–hand movement]). An equal number ( n = 9) expressed a preference for eSight and NuEyes, while ( n = 3) preferred the Moverio. Participants emphasized ease of use, including HMD controls and screen, as common reasons for preference. Those with lower IVI well-being scores preferred eSight due to vision improvement. Those with moderate IVI well-being scores preferred NuEyes due to comfort and size. Those with high IVI well-being scores cited usability as the most important feature. Discussion: User preferences for HMD features were associated with VRQOL. A mixed-methods approach explained how varying degrees of visual impairment and HMD preferences were qualitatively related to usability at the individual level. Implications for Practitioners: To increase acceptance, new HMD development for low vision should focus on performance, usability, and human factors engineering. Although HMD technology can benefit individuals with low vision, device features and functions vary in meaningful ways based on vision parameters. Practitioners should be aware of how patient and device variations influence preferences when they recommend wearable systems and optimize training to harness these systems.

LENS CAPSULAR FLAP TRANSPLANTATION AS PRIMARY TREATMENT FOR CLOSURE OF LARGE MACULAR HOLES.

To report the long-term outcomes of lens capsular flap transplantation (LCFT) as initial treatment for large macular holes (MHs). Thirteen consecutive eyes with large MHs who received LCFT as primary treatment were reviewed retrospectively. All enrolled eyes underwent standard 23-gauge vitrectomy, internal limiting membrane peeling, LCFT, and 15% perfluoropropane tamponade. Autologous whole blood was applied in selected eyes to make the LCT intact. A face-down position maintained for 2 weeks postoperatively. Data including demographic information, medical history, anatomical and functional outcomes, and complications were recorded. The mean preoperative MHs diameter was 979.42 ± 388.28 µm. Eight eyes received autologous LCFT, and the other five eyes received allogenic LCFT. Whole blood was applied in seven eyes. The mean follow-up duration was 19.57 ± 6.24 months (range: 12.0-32.2 months). The macular hole was successfully closed in all cases (13/13). The median best-corrected visual acuity improved from 1.76 (interquartile range, 1.23-1.91) logarithm of the minimum angle of resolution (median Snellen acuity: 20/1,150) preoperatively to 1.16 ± 0.47 logarithm of the minimum angle of resolution (mean Snellen acuity: 20/290) (P < 0.01) at the last visit. No severe complications were noted. Lens capsular flap transplantation may help to improve the closure rate and visual outcomes in large MHs, which could be an alternative method as primary treatment for large MHs.

LONG-TERM SURGICAL OUTCOMES OF LENS CAPSULAR FLAP TRANSPLANTATION IN THE MANAGEMENT OF REFRACTORY MACULAR HOLE.

To report long-term surgical outcomes of autologous and allogenic lens capsular flap transplantation (LCFT) in refractory macular hole (MH) treatment. Fifty consecutive eyes with refractory MH who received LCFT were reviewed retrospectively. Twelve eyes underwent autologous LCFT (LCF obtained from the same eye in 7 eyes and the fellow eye in 5 eyes) and 38 eyes with allogenic LCFT. All eyes underwent complete vitrectomy, internal limiting membrane peeling if not peeled, LCF transplantation, and 15% perfluoropropane tamponade. Simultaneous autologus whole-blood application was applied in 31 eyes to reduce LCF dislocation. The patients maintained a facedown position for 2 weeks postoperatively. Demographic information, functional results, and structural changes were evaluated. The mean preoperative MH diameter was 1,102.00 µm ± 561.63 µm. The mean follow-up duration was 18.50 months ± 6.05 months (range, 12.0-38.9 months). The MH was completely closed in 48 eyes (96.00%) (18 eyes receiving autologous LCFT and 30 receiving allogenic LCFT). There are no differences of age, previous MH surgery times, MH diameter, preoperative and postoperative best-corrected visual acuity, and closure rate between the subgroups. The median visual acuity improved from 1.78 (interquartile range, 1.28-1.85) logarithm of the minimum angle of resolution (median Snellen acuity: 20/1,200) preoperatively to 1.00 (interquartile range, 0.90-1.70) logarithm of the minimum angle of resolution (median Snellen acuity: 20/200) (P < 0.01) in all patients. Both autologous and allogenic LCFT application may provide anatomical and visual improvements in refractory MH cases. Blood application can be applied in selected cases to reduce LCF dislocation. LCFT can be performed as first-line treatment for refractory MHs.

PATCHING RETINAL BREAKS WITH HEALAFLOW IN 27-GAUGE VITRECTOMY FOR THE TREATMENT OF RHEGMATOGENOUS RETINAL DETACHMENT.

To report the surgical outcomes of primary rhegmatogenous retinal detachment (RRD) repaired by 27-gauge pars plana vitrectomy combined with Healaflow patch and air tamponade. In an initial vitro experiment, we observed and compared the dissolution and displacement of the dispersion spots of 0.05-mL Healaflow and sodium hyaluronate. We then performed a prospective, interventional cohort study on 38 eyes in 37 consecutive patients with primary rhegmatogenous retinal detachment. All eyes underwent pars plana vitrectomy combined with Healaflow patch and air tamponade; the postoperative period did not involve prone positioning. The primary and final anatomical attachment rate, best-corrected visual acuity, and intraoperative and postoperative complications were evaluated. In the in vitro experiment, the viscoelastic Healaflow remained adherent with no change in the size of the area; however, the control dissolved completely in the balance solution. The patient study included 16 women (43.2%) and 21 men (56.8%) (mean age, 59.5 ± 9.5 years; mean follow-up period, 8.9 ± 3.8 months). A single break was present in 21 (55.3%) and 2 to 5 breaks in 17 cases (44.8%). The macula was involved in 25 (65.8%) and attached in 13 cases (34.2%) intraoperatively. Initial reattachment was achieved in 37 (97.4%) and final reattachment in 38 cases (100%). In one case (2.6%), the macula redetached because of failure of the chorioretinal scar to develop around the treated break. Mean preoperative and postoperative best-corrected visual acuities were 1.02 ± 0.82 logarithm of the minimum angle of resolution (median Snellen acuity: 20/125, range: 20/20,000-20/20) and 0.23 ± 0.17 logarithm of the minimum angle of resolution (median Snellen acuity: 20/32, range: 20/100-20/20), respectively (P < 0.001). Intraocular pressure was elevated transiently in 28 eyes (73.7%). There were no other intraoperative complications or postoperative scleral incision leakage. A 27-gauge pars plana vitrectomy combined with Healaflow patch, and air tamponade results in a high reattachment rate in the treatment of rhegmatogenous retinal detachment. Thus, patients can benefit from early visual recovery and less complications.

AUTOLOGOUS LENS CAPSULAR FLAP TRANSPLANTATION COMBINED WITH AUTOLOGOUS BLOOD APPLICATION IN THE MANAGEMENT OF REFRACTORY MACULAR HOLE.

To report results of lens capsular flap transplantation (LCFT) and autologous whole blood application in refractory macular hole (MH) treatment. Seven phakic and three aphakic eyes with persistent MH after standard surgery with internal limiting membrane peeling were studied. Lens capsule flap was acquired from the same eye in eight cases (seven phakic and one aphakic). The fellow eye was used in two aphakic eyes without sufficient lens capsule. The fellow eye underwent simultaneous phacoemulsification. All eyes underwent complete vitrectomy, LCFT into the MH, whole blood application, and 15% perfluoropropane (C3F8) tamponade. The patients were instructed to maintain a face-down or prone position for two weeks postoperatively. Structural and functional changes were evaluated. The mean preoperative MH diameter was 1,472.78 ± 736.88 μm. The MH was completely closed in nine eyes: eight eyes receiving same-eye LCFT and one receiving fellow-eye LCFT. In the other fellow-eye LCFT recipient, the MH was partially closed. Visual acuity improved from 1.84 ± 0.49 logarithm of the minimum angle of resolution (median Snellen acuity: 20/1,750, range: 20/4,000-20/125) preoperatively to 1.34 ± 0.59 logarithm of the minimum angle of resolution (median Snellen acuity: 20/450, range: 20/4,000-20/63) postoperatively (P = 0.009). Lens capsular flap transplantation and autologous whole blood application may improve anatomical and visual outcomes in refractory MH cases. The lens equator and fellow eye may be promising sources of LCF.

INTRAVITREAL TISSUE PLASMINOGEN ACTIVATOR, PERFLUOROPROPANE (C3F8), AND RANIBIZUMAB OR PHOTODYNAMIC THERAPY FOR SUBMACULAR HEMORRHAGE SECONDARY TO WET AGE-RELATED MACULAR DEGENERATION

To report a combined intravitreal treatment for submacular hemorrhage. This retrospective, noncomparative, interventional case series included 7 patients with neovascular age-related macular degeneration and 2 with idiopathic polypoidal choroidal vasculopathy, presenting with fovea-involving submacular hemorrhage ≥ 4 disk areas in size, of <10 days of duration. All patients received a single 0.05-mL intravitreal injection of 50 μg alteplase, 0.3 mL of 100% C3F8, and facedown positioning for 1 week. Patients with newly diagnosed age-related macular degeneration received 3 consecutive monthly intravitreal injections of 0.5 mg ranibizumab, followed by monthly retreatment as needed. Those with idiopathic polypoidal choroidal vasculopathy were treated with photodynamic therapy. Mean (± SD) logarithm of the minimum angle of resolution visual acuity improved from 0.75 ± 0.35 at presentation to 0.35 ± 0.30 at a mean final follow-up of 15.1 months (P = 0.0078). Median Snellen acuity improved from 20/200 to 20/32. Visual acuity was stable in one case and improved in eight. The average size of submacular hemorrhage was 6.8 disk areas at presentation, reducing to 2.6 within 1 month (P = 0.0039). Subfoveal hemorrhage was displaced in all cases within 9 weeks. The mean pretreatment central retinal thickness of 669 μm reduced to 528 μm (P = 0.0039). One case developed transiently elevated intraocular pressure. Two developed breakthrough vitreous hemorrhage. No adverse events were attributed to tissue plasminogen activator. Tissue plasminogen activator and C3F8, combined with intravitreal ranibizumab or photodynamic therapy, may result in anatomical clearance of submacular hemorrhage and improved visual acuity, in a condition with an otherwise poor visual prognosis.

The Ahmed Versus Baerveldt Study: One-Year Treatment Outcomes

Objective To report the 1-year treatment outcomes of the Ahmed Versus Baerveldt (AVB) Study. Design Multicenter randomized clinical trial. Participants A total of 238 patients were enrolled in the study, including 124 in the Ahmed group and 114 in the Baerveldt group. Methods Patients aged 18 years or older with uncontrolled glaucoma refractory to medicinal, laser, and surgical therapy were randomized to undergo implantation of an Ahmed-FP7 valve (New World Medical, Inc., Rancho Cucamonga, CA) or a Baerveldt-350 implant (Abbott Medical Optics, Inc., Santa Ana, CA), to be followed for 5 years. Main Outcome Measures The primary outcome measure was failure, defined as intraocular pressure (IOP) out of target range (5–18 mmHg with ≥20% reduction from baseline) for 2 consecutive visits after 3 months, vision-threatening complications, additional glaucoma procedures, or loss of light perception. Secondary outcome measures included IOP, medication use, visual acuity, complications, and interventions. Results There were no significant differences in baseline ocular or demographic characteristics between the study groups with the exception of sex. Preoperatively, the study group had a mean IOP of 31.4±10.8 mmHg on a mean of 3.1±1.0 glaucoma medications with a median Snellen acuity of 20/100. The cumulative probability of failure a 1-year was 43% in the Ahmed group and 28% in the Baerveldt group (P=0.02). The mean IOP at 1 year was 16.5±5.3 mmHg in the Ahmed group and 13.6±4.8 mmHg in the Baerveldt group (P < 0.001). The mean number of glaucoma medications required was 1.6±1.3 in the Ahmed group and 1.2±1.3 in the Baerveldt group (P=0.03). Visual acuity was similar in both groups at all visits in the first year (P=0.66). In the first year after surgery, there were a similar number of patients who experienced postoperative complications in the 2 groups (45% Ahmed, 54% Baerveldt, P=0.19), but a greater number of patients in the Baerveldt group required interventions (26% Ahmed vs. 42% Baerveldt, P=0.009). Conclusions The Baerveldt-350 group had a higher success rate than the Ahmed-FP7 group after 1 year of follow-up, but required a greater number of interventions. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references. To report the 1-year treatment outcomes of the Ahmed Versus Baerveldt (AVB) Study. Multicenter randomized clinical trial. A total of 238 patients were enrolled in the study, including 124 in the Ahmed group and 114 in the Baerveldt group. Patients aged 18 years or older with uncontrolled glaucoma refractory to medicinal, laser, and surgical therapy were randomized to undergo implantation of an Ahmed-FP7 valve (New World Medical, Inc., Rancho Cucamonga, CA) or a Baerveldt-350 implant (Abbott Medical Optics, Inc., Santa Ana, CA), to be followed for 5 years. The primary outcome measure was failure, defined as intraocular pressure (IOP) out of target range (5–18 mmHg with ≥20% reduction from baseline) for 2 consecutive visits after 3 months, vision-threatening complications, additional glaucoma procedures, or loss of light perception. Secondary outcome measures included IOP, medication use, visual acuity, complications, and interventions. There were no significant differences in baseline ocular or demographic characteristics between the study groups with the exception of sex. Preoperatively, the study group had a mean IOP of 31.4±10.8 mmHg on a mean of 3.1±1.0 glaucoma medications with a median Snellen acuity of 20/100. The cumulative probability of failure a 1-year was 43% in the Ahmed group and 28% in the Baerveldt group (P=0.02). The mean IOP at 1 year was 16.5±5.3 mmHg in the Ahmed group and 13.6±4.8 mmHg in the Baerveldt group (P < 0.001). The mean number of glaucoma medications required was 1.6±1.3 in the Ahmed group and 1.2±1.3 in the Baerveldt group (P=0.03). Visual acuity was similar in both groups at all visits in the first year (P=0.66). In the first year after surgery, there were a similar number of patients who experienced postoperative complications in the 2 groups (45% Ahmed, 54% Baerveldt, P=0.19), but a greater number of patients in the Baerveldt group required interventions (26% Ahmed vs. 42% Baerveldt, P=0.009). The Baerveldt-350 group had a higher success rate than the Ahmed-FP7 group after 1 year of follow-up, but required a greater number of interventions.

Relation of Visual Function to Retinal Nerve Fiber Layer Thickness in Multiple Sclerosis

To examine the relation of visual function to retinal nerve fiber layer (RNFL) thickness as a structural biomarker for axonal loss in multiple sclerosis (MS), and to compare RNFL thickness among MS eyes with a history of acute optic neuritis (MS ON eyes), MS eyes without an optic neuritis history (MS non-ON eyes), and disease-free control eyes. Cross-sectional study. Patients with MS (n = 90; 180 eyes) and disease-free controls (n = 36; 72 eyes). Retinal never fiber layer thickness was measured using optical coherence tomography (OCT; fast RNFL thickness software protocol). Vision testing was performed for each eye and binocularly before OCT scanning using measures previously shown to capture dysfunction in MS patients: (1) low-contrast letter acuity (Sloan charts, 2.5% and 1.25% contrast levels at 2 m) and (2) contrast sensitivity (Pelli-Robson chart at 1 m). Visual acuity (retroilluminated Early Treatment Diabetic Retinopathy charts at 3.2 m) was also measured, and protocol refractions were performed. Retinal nerve fiber layer thickness measured by OCT, and visual function test results. Although median Snellen acuity equivalents were better than 20/20 in both groups, RNFL thickness was reduced significantly among eyes of MS patients (92 mum) versus controls (105 mum) (P<0.001) and particularly was reduced in MS ON eyes (85 mum; P<0.001; accounting for age and adjusting for within-patient intereye correlations). Lower visual function scores were associated with reduced average overall RNFL thickness in MS eyes; for every 1-line decrease in low-contrast letter acuity or contrast sensitivity score, the mean RNFL thickness decreased by 4 mum. Scores for low-contrast letter acuity and contrast sensitivity correlate well with RNFL thickness as a structural biomarker, supporting validity for these visual function tests as secondary clinical outcome measures for MS trials. These results also suggest a role for ocular imaging techniques such as OCT in trials that examine neuroprotective and other disease-modifying therapies. Although eyes with a history of acute optic neuritis demonstrate the greatest reductions in RNFL thickness, MS non-ON eyes have less RNFL thickness than controls, suggesting the occurrence of chronic axonal loss separate from acute attacks in MS patients.