Improved Contrast Sensitivity Research Articles

Playing three-dimensional video games boosts stereo vision

Playing two-dimensional video games has been shown to result in improvements in a range of visual and cognitive tasks, and these improvements appear to generalize widely1,2,3,4,5,6. Here we report that young adults with healthy vision, surprisingly, showed a dramatic improvement in stereo vision after playing three-dimensional, but not two-dimensional, video games for a relatively short period of time. Intriguingly, neither group showed any significant improvement in binocular contrast sensitivity. This dissociation suggests that the visual enhancement was specific to genuine stereoscopic processing, not indirectly resulting from enhanced contrast processing, and required engaging in a disparity cue-rich three-dimensional environment.

Limited restoration of contrast sensitivity with training after V1 damage in humans.

Stroke damage to the primary visual cortex (V1) causes severe visual deficits, which benefit from perceptual retraining. However, whereas training with high-contrast stimuli can locally restore orientation and motion direction discrimination abilities at trained locations, it only partially restores luminance contrast sensitivity (CS). Recent work revealed that high-contrast discrimination abilities may be preserved in the blind field of some patients early after stroke. Here, we asked if CS for orientation and direction discrimination is similarly preserved inside the blind field, to what extent, and whether it could benefit from a visual training intervention. Thirteen subacute patients (<3 months post-V1-stroke) and 12 chronic patients (>6 months post-V1-stroke) were pre-tested, then trained to discriminate either orientation or motion direction of Gabor patches of progressively lower contrasts as their performance improved. At baseline, more subacute than chronic participants could correctly discriminate the orientation of high-contrast Gabors in their blind field, but all failed to perform this task at lower contrasts, even when 10Hz flicker or motion direction were added. Training improved CS in a greater portion of subacute than chronic participants, but no-one attained normal CS, even when stimuli contained flicker or motion. We conclude that, unlike the near-complete training-induced restoration of high-contrast orientation and motion direction discrimination abilities, V1 damage in adulthood may severely limit the residual visual system's ability to regain normal CS. Our results support the notion that CS involves different neural substrates and computations than those required for orientation and direction discrimination in V1-damaged visual systems.Significance statement Stroke-induced V1 damage in adult humans induces a rapid and severe impairment of contrast sensitivity for orientation and motion direction discrimination in the affected hemifield, although discrimination of high-contrast stimuli can persist for several months. Adaptive training with Gabor patches of progressively lower contrasts improves contrast sensitivity for both orientation and motion discriminations in the blind-field of subacute (<3 months post-stroke) and chronic (>6 months post-stroke) participants; however, it fails to restore normal contrast sensitivity. Nonetheless, more subacute than chronic stroke participants benefit from such training, particularly when discriminating the orientation of static, non-flickering targets. Thus, contrast sensitivity appears critically dependent on processing within V1, with perceptual training displaying limited potential to fully restore it after V1 damage.

Changes in the structure and function of the visual pathway in subjects at high risk for the development of Alzheimer's disease: 27 months of follow‐up

Aims/Purpose: In addition to advanced age, two of the most important risk factors for the development of Alzheimer's disease are having a family history of the disease (FH+) and being a carrier of at least one Ɛ4+ allele for the ApoE gene (ApoE Ɛ4+). AD generates changes in the retina and visual function when the disease is established, so the aim of the present work is to know if these changes appear in healthy subjects but with high genetic risk to develop the disease and to analyse if these changes evolve along 27 months of follow‐up.Methods: A retinal thickness analysis by optical coherence tomography and visual function by assessing visual acuity (VA), contrast sensitivity (CS), colour perception, perception digital test and visual field analysis was completed by all participants. For structural findings analysis subjects were divided into (FH+ ApoE Ɛ4+) and (FH‐ ApoE Ɛ4‐) groups and for functional analysis these subgroups were subdivided by ages between 40 and 60 years and subjects over 60 years.Results: After 27 months of follow‐up, the FH+ ApoE Ɛ4+ group experienced changes in the thickness of all retinal layers except the outer layers. In this group, the inner nuclear layer showed progressing changes, but there was no progression in visual function. However, compared to the FH‐ ApoE Ɛ4‐ group at 27 months, the improvement in visual acuity and contrast sensitivity (3 and 12 cpd) observed during the initial visit was maintained.Conclusions: In cognitively healthy individuals at high risk of developing AD structural changes in the retina continue to progress after 27 months, while functional changes detected at the beginning remain stable.

Wavelength Characteristics and Visual Function of Photochromic Contact Lenses in Indoor and Outdoor Conditions

Purpose: To examine the wavelength characteristics of photochromic contact lenses (CL) and evaluate the impact of tinting on visual function in indoor, outdoor, and glare environments. Methods: A total of 33 healthy individuals with refractive errors were recruited and fully corrected for refractive errors. Three groups were established, including non-activated photochromic CL, activated photochromic CL, and lenses without photochromic properties, which replicated the dimming characteristics of CL. Visual acuity and contrast sensitivity were measured and compared among the three groups. Results: Statistically significant differences were observed in the spatial frequency (6, 12 cpd) and contrast sensitivity outdoors, with improved values recorded in the activated photochromic-CL group. In subsequent comparisons, the activated-photochromic-CL group demonstrated significantly better contrast-sensitivity values than the non-photochromic-CL group, as well as significant improvement in contrast sensitivity compared to the non-activated-photochromic-CL group. No significant differences were observed in the indoor or outdoor visual acuity. Conclusion: Our results suggest that photochromic CL enhances visual function in outdoor environments, while maintaining visual function indoors and under glare, thereby improving the quality of vision (QOV) in severe light conditions where exposure to sunlight and ultraviolet light is anticipated.

Elamipretide Topical Ophthalmic Solution for the Treatment of Subjects with Leber Hereditary Optic Neuropathy: A Randomized Trial

PurposeThe purpose of this study was to assess the safety, tolerability, and potential efficacy of topical elamipretide in patients affected with Leber’s Hereditary Optic Neuropathy (LHON). DesignThis Phase 2, prospective, randomized, vehicle controlled, single-center clinical trial involved administration of elamipretide (MTP-131) topical ophthalmic solution to LHON patients over a 52-week double-masked treatment period (DMTP), followed by an open extension label (OLE) for up to 108 additional weeks of treatment. SubjectsTwelve patients affected with LHON were included in this study. Patients between ages 18 and 50 with decreased vision, for at least one year and no more than ten years, and a genetically confirmed diagnosis of m.11778G>A LHON were eligible for this trial. MethodsFor the first 52 weeks of the study, patients were randomized to one of two arms, elamipretide in both eyes or elamipretide in one eye and vehicle in the other eye, followed by an OLE where both eyes were treated with elamipretide. Main outcome measuresThe primary outcome measure was the assessment of adverse events from the administration of topical elamipretide 1% and the primary efficacy endpoint was change in best corrected visual acuity (BCVA). Secondary outcome measures included changes in color vision, visual field mean deviation, and electrophysiological outcomes. ResultsElamipretide was well tolerated with the majority of treatment-emergent adverse events (TEAEs) being mild to moderate and resolving spontaneously. The change from baseline in BCVA in elamipretide-treated eyes was not significantly different from the vehicle eyes at any time point. Six of 12 subjects met the criteria for clinically relevant benefit (CRB). In the post-hoc analysis, change from baseline in mean deviation in the central visual field was significantly greater in elamipretide treated eyes versus the vehicle eyes. Compared to baseline, both treatment groups showed improvement in color discrimination and contrast sensitivity in the OLE. ConclusionsElamipretide treatment was generally well tolerated with no serious adverse events reported. Although this study did not meet its primary BCVA efficacy endpoint, improvements across assessments on visual function during the OLE, and the post-hoc findings of the HVF central region, were encouraging and require further exploration.

Clinical study of functional visual recovery following phacoemulsification with IOL implantation

Aim To evaluate the functional visual recovery following phacoemulsification cataract surgery with foldable intraocular lens implantation through a temporal clear corneal incision. Methodology This prospective study was conducted at a tertiary health care centre in Western Maharashtra over a period of 2 years. Detailed history was taken and thorough ocular examination of was done. Visual Acuity, Color vision, Contrast sensitivity, Binocular vision was noted. Visual Fields were examined and Glare Disability was assessed. All patients underwent temporal clear corneal Phacoemulsification surgery through a 3.2 mm incision with implantation of an Aspheric Monofocal Foldable IOL under LA. All patients were started on tapering dose of antibiotic − steroid over 6 weeks and followed up post operatively on day 1, week 1, week 2, 6 weeks, 3months and at 6 months. Results 50 eyes of 46 patients with immature cataract aged between 40 to 80 years were included. At the end of 24 weeks the Distance Vision was ≥ 6/9 in 31 eyes, 6/18–6/12 in 17 eyes and &lt; 6/18 in 2 eyes. It was a statistically significant difference (P&lt;0.0001). No significant difference in near vision was seen at the end of 6 months. The difference in astigmatism post operatively in all 50 eyes was not statistically significant at the end of 6 months (P&lt;0.05). Significant improvement in contrast sensitivity was seen post operatively (P&lt;0.0001). The mean glare disability was 14.06 s at 24 weeks. No significant difference was seen (P&gt;0.05). Colour vision and Field of vision were similar postoperatively. All the patients maintained grade 3 binocular vision at end of the study. Conclusion Phacoemulsification with monofocal foldable intraocular lenses can be the choice of technique in treatment of cataract as being able to provide excellent visual results and also being cost effective.

Correlation between Visual Acuity, Contrast Sensitivity and Depth of Vision before and after Partial Time Occlusion Therapy in Strabismic and Anisometropic Amblyopes

Background Amblyopia is known as the visual developmental disorder that follows selective disruption of the visual input to one eye early in life. It is considered the second most common cause of decreased visual acuity in both children and adults affecting greatly both economic and social life. It affects most of the visual parameters, so great efforts are carried out in developing effective methods controlling different deficits in amblyopia, being a great concern for all the society. However, monocular occlusion therapy remains the easiest and most popular way despite that there are many doubts in its reliability in controlling visual abnormalities other than acuity. Purpose To compare the different performance of anisometropic and strabismic eyes with moderate amblyopia, using partial occlusion therapy regarding visual acuity, contrast sensitivity and depth of vision. Methods Forty-nine children between 7 and 12 years old suffering from moderate amblyopia were classified into two groups: 25 anisometropic amblyopes and 24 strabismic ones. Two hour occlusion regimen with near activity was conducted by patients, assured by parents monitoring. Evaluation of visual acuity, contrast sensitivity and stereoacuity was conducted at each visit throughout the treatment regimen which was continued for 6 months on monthly follow up basis. Results Children in both groups improved significantly in visual acuity. There was a considerable difference among the distribution of improvement within each group where 9% of strabismic amblyopes achieved full visual recovery as compared to 40% in the anisometropic group, and 62.5% had residual amblyopia as compared to 36% in the anisometropic one, in spite of no significant difference of average improvement between groups (&amp;lt;0.0001). Only 42% of the strabismic amblyopes improved in stereoacuity as compared to 88% of the anisometropic ones, however, the difference in mean improvement was not significant between the two groups. Conclusion Children with moderate anisometropic or strabismic amblyopia 7-12 years old, can get considerable benefits from part time occlusion therapy in different visual aspects. The anisometropic amblyopes have better contrast sensitivity improvement and more reliable expectations of recovery being largely dependent on the initial visual acuity.

Three wavelength cut lenses with improved contrast sensitivity and reduced lens color

Three wavelength cut lenses with improved contrast sensitivity and reduced lens color

EXPLORING THE EFFECT OF A VISUAL TELEREHABILITATION PROGRAM ON VISUAL PERCEPTION IN CHILDREN AND ADOLESCENTS WITH HEMIANOPIA CONSECUTIVE TO A BRAIN TUMOUR, PRELIMINARY RESULTS OF A PILOT STUDY

Abstract Brain tumours (BT) in children often lead to visual impairment, which represents a significant morbidity for long-term survivors. A recent Children Cancer Survivor Study showed that 22.5% of patients with astroglial tumours had visual impairment 5 years after the diagnosis. In the pediatric population with hemianopia, there are no standardized protocols for managing vision loss. In this pilot study, a 6-week home-based visual telerehabilitation program (VTP) evaluated visual changes in 10 children with hemianopia consecutive to a BT. METHOD: The study included 10 patients aged 8-18 years old with hemianopia consecutive to a pediatric BT. Five patients had a chiasmatic tumour (CT), other 5 had a tumour located outside of the chiasm (OCT). Patients followed a 6-week VTP on a virtual reality device at home with remote control of the device from the UHN laboratory. Visual assessments performed at baseline, 2, 4, 6 weeks with follow-ups at 1 and 6 months to check the visual field, contrast sensitivity and reading speed. A quality-of-life (QoL) questionnaire was also filled by patients and parents at every visit. RESULTS: The preliminary results of 8 patients have been analyzed. Four patients (3 CT, 1 OCT) showed visual field improvement with increased luminance perception in the monocular Humphrey test. Four patients (2 CT, 2 OCT) showed visual field improvement in the binocular Esterman field analysis. Reading speed improved in 6 patients (3CT, 3OCT). All patients had significant improvement in contrast sensitivity and QoL. CONCLUSION: Preliminary results of this study showed that this VTP was feasible in children. The program was effective, especially for patients with CT in improving visual field with an impact on contrast sensitivity, reading speed and QoL. Further studies are in development to confirm these results and identify the most appropriate schedules to optimize visual outcomes. POSTER CATEGORIES: BS = BASIC SCIENCE CS = CLINICAL SCIENCE RO = RADIATION ONCOLOGY MO = MEDICAL ONCOLOGY M = MISCELLANEOUS POSTER/TRAVEL AWARDS provided by: BTFC = Brain Tumour Foundation of Canada OHRI = Ottawa Hospital Research Institute

Effectiveness of Optometric Photo-Therapy in Amblyopia

Anisometropic amblyopia is amblyopia due to difference of ≥1 D refractive error between two eyes. Objectives: To determine effect of optometric phototherapy on Visual Acuity and Contrast Sensitivity in older children with anisometropic amblyopia and to assess frequency of different degrees of amblyopia. Methods: A Quasi Experimental study was carried at Madinah Teaching Hospital and DHQ, Faisalabad. A total of anisometropic amblyopia subjects of both gender with age ranging from 8 to 18 years who had undergone refractive adaptation were included in the study. Other types of amblyopia and subjects who previously got treated for amblyopia were excluded. Subjects were given optometric photo-therapy for 4 weeks with red amber filter and post assessment was recorded. Descriptive and Paired sample t test statistical analysis was done with SPSS version 27.0. Results: 64% of the subjects had moderate amblyopia, 20% had mild amblyopia while only 16% had severe amblyopia. Visual Acuity improved from .4944 ± .19040 to .3552 ± .20390 (p&lt;0.001) while Contrast Sensitivity improved from 1.3980 ± .21529 to 1.5480 ± .21960 (p&lt;0.001) in optometric photo-therapy. Conclusions: Moderate amblyopia had more prevalence in comparison to both mild and severe amblyopia and Optometric Photo-therapy showed improvement of both visual acuity and contrast sensitivity in anisometropic amblyopia.

Standard Amblyopia Therapy in Adults with Longstanding Amblyopia Improves Visual Acuity and Contrast Sensitivity.

Perceptual learning or dichoptic training may result in improved acuity in adult amblyopes. However, for amblyopic children (<18 years), most clinicians recommend standard part-time patching. The purpose of this study was to determine if standard amblyopia therapy results in an enhancement in vision in the amblyopic eye of adults. Fifteen amblyopes (20/30 or worse) were recruited and nine (age (SD) 32.9 (16.31)) with anisometropia or anisometropia and strabismus (ie, combined mechanism amblyopia) completed the study. Previous therapy did not exclude subjects. The subjects received a comprehensive eye exam and wore their best correction for at least four weeks prior to baseline testing. The non-amblyopic eye was patched for 2 hours per day (Amblyopia iNET training for 30 minutes and near/distance activities for 1.5 hours). The subjects had a baseline amblyopia evaluation followed by one visit per week for 12 weeks. At 12 weeks, the treatment was tapered off over one month and the subjects had a final amblyopia evaluation at 24 weeks. Contrast sensitivity was measured at baseline and 12 weeks with the Quick CSF system. The subjects had a significant improvement in visual acuity across the weeks (p < 0.001). At baseline, weeks 12 and 24, the average logMAR acuities (SE) were 0.55 (0.09), 0.41 (0.08), and 0.38 (0.09), respectively. Weeks 4 to 24 were significantly different (p < 0.001) from baseline. The average acuity improvement over the 24 weeks was 1.7 logMAR lines. There was a significant increase in the area under the log contrast sensitivity function (p = 0.002) and its estimated acuity (p = 0.036) from baseline to 12 weeks. Standard amblyopia treatment can result in an improvement in visual acuity and contrast sensitivity in adults with longstanding anisometropic or combined mechanism amblyopia even if they had prior therapy.

The effect of filters and varying illumination on contrast sensitivity in eyes with moderate to severe visual impairment.

To investigate the effect of filters and illumination on contrast sensitivity in persons with cataract, pseudophakia, maculopathy and glaucoma to provide a guide for eye care providers in low vision rehabilitation. A within-subjects experimental design with a counter-balanced presentation technique was employed in this study. The contrast sensitivity of eyes with cataract, pseudophakia, maculopathy and glaucoma was measured with filters (no filter, yellow, pink and orange) combined with increasing illumination levels (100lx, 300lx, 700lx and 1000lx) using the SpotChecks™ contrast sensitivity chart. The data were analyzed using descriptive statistics and two-way repeated measures ANOVA. The yellow filter at 100lx significantly improved contrast sensitivity in the maculopathy group. There were no significant improvements with either intervention in the rest of the groups. There was, however, a significant interaction between filters and illumination in the cataract group. There were small improvements in contrast sensitivity at low illumination levels with the yellow filter in the maculopathy group, and this could be considered in clinical practice and low vision rehabilitation. Overall, filters at most illumination levels did not benefit most groups.

A 3-month comparison study of subjective and objective visual quality of small incision lenticule extraction and transepithelial photorefractive keratectomy in patients with low and moderate myopia.

To compare the subjective and objective visual quality between small incision lenticule extraction (SMILE) and transepithelial photorefractive keratectomy (tPRK) in patients with low and moderate myopia. Patients undertaking SMILE or tPRK for the correction of low and moderate myopia were consecutively recruited in this prospective cohort study with a 3-month follow-up period. Objective evaluation [visual acuity test, manifest refraction, wavefront aberrations, the total cut-off value of the total modulation transfer function (MTFcut-off), and Strehl ratio (SR)] and subjective evaluation of visual quality (quality-of-life questionnaire) were conducted before surgery and at days 1, 7, 30, and 90 after surgery. A total of 47 patients (94 eyes) with SMILE and 22 patients (22 eyes) with tPRK were enrolled. The uncorrected visual acuity (UCVA) was better in SMILE patients on day 7 after surgery (1.13±0.13 vs 0.99±0.17, t=4.85, P<0.001) but was comparable at days 30 and 90. At day 90, the SMILE group had a lower spherical equivalent (SE) than the tPRK group (0.04±0.31 vs 0.19±0.43, t=2.08, P=0.042). Total higher order aberrations (HOAs) were induced in both surgical types, which were more evident in the tPRK group with 3-mm pupil diameter (0.16±0.07 vs 0.11±0.05, t=4.27, P<0.001) and 5-mm pupil diameter (0.39±0.17 vs 0.36±0.11, t=2.33, P=0.022). The MTFcut-off and SR showed a trend of improvement in both SMILE and tPRK patients but were statistically better in the SMILE group with both pupil diameters. There was a significant improvement of contrast sensitivity (CS) over baseline levels at the spatial frequency of 18 cycles/degree (c/d) in the SMILE group (F=2.72, P=0.033) and at 3 c/d (F=3.03, P=0.031), 12 c/d (F=3.72, P=0.013), and 18 c/d (F=4.62, P=0.004) in the tPRK group. The subjective quality of life questionnaire showed a steady improvement in the SMILE group (F=8.31, P<0.001) but not the tPRK group. SMILE and tPRK are both safe and effective ways to correct low and moderate myopia. A generally better and quicker recovery of visual quality favors the application of SMILE in qualified patients.

Are wearable electronic vision enhancement systems (wEVES) beneficial for people with age-related macular degeneration? A scoping review.

Age-related macular degeneration (AMD) is the most common cause of irreversible visual impairment in the United Kingdom. It has a wide-ranging detrimental impact on daily living, including impairment of functional ability and quality of life. Assistive technology designed to overcome this impairment includes wearable electronic vision enhancement systems (wEVES). This scoping review assesses the usefulness of these systems for people with AMD. Four databases (Cumulative Index to Nursing and Allied Health Literature, PubMed, Web of Science and Cochrane CENTRAL) were searched to identify papers that investigated image enhancement with a head-mounted electronic device on a sample population that included people with AMD. Thirty-two papers were included: 18 studied the clinical and functional benefits of wEVES, 11 investigated use and usability and 3 discussed sickness and adverse effects. Wearable electronic vision enhancement systems provide hands-free magnification and image enhancement producing significant improvements in acuity, contrast sensitivity and aspects of laboratory-simulated daily activity. Adverse effects were infrequent, minor and spontaneously resolved with the removal of the device. However, when symptoms arose, they sometimes persisted with continued device usage. There are multi-factorial influences and a diversity of user opinions on promotors to successful device use. These factors are not exclusively driven by visual improvement and incorporate other issues including device weight, ease of use and inconspicuous design. There is insufficient evidence of any cost-benefit analysis for wEVES. However, it has been shown that a user's decision to make a purchase evolves over time, with their estimates of cost falling below the retail price of the devices. Additional research is needed to understand the specific and distinct benefits of wEVES for people with AMD. Further patient-centred research should assess the benefits of wEVES in user-led activities when directly compared with alternative coping strategies, allowing professionals and users to make better prescribing and purchasing decisions.

Optical Coherence Tomography Angiographic Evaluation of Macular Vessel Density in Diabetic Macular Edema After Intravitreal Dexamethasone Implants: A Prospective Interventional Trial.

The goal of this study was to assess macular vascular density evolution, macular thickness, and functional outcomes after intravitreal dexamethasone implants for diabetic macular edema. Vascular density was evaluated with optical coherence tomography (OCT) angiography in 21 eyes. Macular thickness was evaluated with structural OCT. Visual acuity and contrast sensitivity were evaluated before and after treatment, and these functional outcomes were analyzed for association with anatomic outcomes. Macular vessel density in the superficial capillary plexus was evaluated with OCT angiography and quantified in areas with no fluid, allowing a more accurate measurement and eliminating the segmentation bias in areas with intra-retinal fluid. Such a methodology was possible by positioning the scans only in areas with no fluid before and after the implant. The absence of fluid in these areas was confirmed by three experienced evaluators using both the B-scan and the en face. Visual acuity and contrast sensitivity were evaluated before and after treatment, and these functional outcomes were analyzed for association with anatomic outcomes. At 30, 60, and 90 days after implantation, there was improvement in macular perfusion in areas without fluid after intravitreal dexamethasone implantation, accompanied by reduced macular thickness and improved visual acuity (P < .001). However, there was no improvement in contrast sensitivity after treatment. Improved macular perfusion after treatment with intravitreal dexamethasone implantation may be associated with modulation of leukostasis, when the release of cytokines leads to capillary endothelial damage and obstruction of the micro-vasculature, leading to impaired capillary perfusion and ischemic damage. Despite the anatomical and functional findings demonstrated, further studies are needed to prove the relationship between the inflammatory mechanisms of diabetic macular edema and its relationship with macular perfusion and functional aspects. [Ophthalmic Surg Lasers Imaging Retina 2023;54(3):174-182.].

Effect of Cataract Extraction with Intraocular Lens Implant on Contrast Sensitivity, Colour Vision and Photostress Recovery Time

A cataract is a cloudy area in the lens of the eye that can lead to a reduction in vision and visual functions. This study was a clinical study aimed at determining the effect of cataract extraction with intraocular lens (IOL) implant on contrast sensitivity, color vision and photostress recovery time. A total of 70 patients who visited Ajeromi General Hospital, Lagos, Nigeria were used for the study. Contrast sensitivity was assessed using the Pelli-Robson contrast sensitivity chart. The colour vision of the subjects was assessed using Ishihara Pseudochromatic colour vision chart and the photostress recovery time was assessed using a bright ophthalmoscope light. Results showed that the mean contrast sensitivity of the subjects before cataract extraction with IOL implant was 1.04±0.08. After cataract extraction, the mean was 2.19±0.07. The mean colour vision test value before cataract extraction with IOL implant was 14.41±0.53. After cataract extraction, the mean was 16.00±0.00. The mean Photostress Recovery Time before cataract extraction with IOL implant was 55.77±1.81 seconds. After cataract extraction, the mean was 29.11±0.83 seconds. SPSS data analysis with the Paired sample T-Test at 0.05 level of significance showed a significant improvement (P&lt;0.05) in contrast sensitivity, color vision and photostress recovery time before and after cataract extraction with IOL implant. It was recommended that all patients with monocular and bilateral cataract be referred for cataract extraction with intraocular lens (IOL) implant. Keywords: Cataract, Intraocular lens, Contrast sensitivity, Color vision, Photostress recovery time

Quality of Life (QoL) in Non-Acute Vogt–Koyanagi–Harada Disease (VKHD) at Two Time Points 24 Months Apart

ABSTRACT Aims To investigate the changes in quality-of-life (QoL) metrics at a 24-month interval in non-acute VKHD patients and their association with inflammation, treatment, and visual function. Methods SF-36 and VFQ-25 questionnaires were administered at two 24-month-apart moments to 22 non-acute VKHD patients followed for ≥12 months since acute disease onset. “Improvement,” “unchanged,” or “worsening” in questionnaires scores (difference >5-point) between M1 and M2 and their associations were sought. Results Absence of systemic treatment or optic disc hyperfluorescence was associated with improved general health (SF-36). Improvement in binocular contrast sensitivity resulted in better ocular pain score; absence of anterior uveitis relapse, stable fundus findings, no use of cyclosporine or no intravitreal injections resulted in unchanged/better dependency score; no intravitreal injections resulted in unchanged/better mental health score (VFQ-25). Conclusion Stability/improvement in QoL scores was associated with controlled inflammation, better visual function, and no need for treatment. Subclinical inflammatory signs did not impact QoL scores.

Non-steroidal anti-inflammatory agents for treating cystoid macular edema following cataract surgery.

Non-steroidal anti-inflammatory agents for treating cystoid macular edema following cataract surgery.

A randomized phase 2 clinical trial of phentolamine mesylate eye drops in patients with severe night vision disturbances

PurposeDim light vision disturbances (DLD) comprise a wide range of symptoms affecting the quality of vision at low illumination including glare, halos, and starbursts. This exploratory study investigated 1.0% phentolamine mesylate ophthalmic solution (PMOS) as a treatment to improve vision and image quality for patients with DLD.MethodsIn this placebo-controlled, randomized, double-masked clinical trial, 24 adult patients with severe DLD were randomized in a 2:1 ratio to receive either one dose of PMOS or placebo. Subjects were eligible if they reported experiencing severe night vision difficulty that was not eliminated by distance spectacle correction and scored ≥0.3 log units below the normal range of contrast sensitivity assessed under mesopic conditions with glare at ≥2 spatial frequencies. Key efficacy outcomes were change from baseline in pupil diameter, contrast sensitivity, and visual acuity. Safety measures including intraocular pressure, conjunctival hyperemia, and systemic effects were also assessed.ResultsEight subjects were randomized to placebo (63% female; mean age 47 years) and 16 were randomized to PMOS (75% female; mean age 42 years). Mean (SD) pupil diameter of PMOS-treated subjects decreased significantly − 1.3 mm (0 to − 2.8 mm) with p < 0.0001. Mean contrast sensitivity with glare in PMOS-treated subjects improved significantly post-treatment at spatial frequencies 3, 6, 12, and 18 cycles per degree (p ≤ 0.03). PMOS also demonstrated improvements in the numbers of letters read for mesopic and photopic, high- and low-contrast visual acuity (LCVA). Importantly, a statistically greater proportion of PMOS-treated eyes registered mesopic LCVA 5 letter (69% vs. 31%, p = 0.029) and 10 letter (34% vs. 6%, p = 0.04) improvement, with a trend at 15 letters (19% vs. 0%, p = 0.16). PMOS was well tolerated with the only reported side effect being a mild increase in conjunctival hyperemia.ConclusionPMOS was well tolerated and effectively reduced pupil size with improvements in contrast sensitivity and visual acuity in adults with severe DLD. Future Phase 3 studies should be conducted to further evaluate its potential to treat DLD.Trial registrationThe trial registration number is NCT04004507 (02/07/2019). Retrospectively registered.

Carbon dioxide and blood-feeding shift visual cue tracking during navigation in Aedes aegypti mosquitoes.

Haematophagous mosquitoes need a blood meal to complete their reproductive cycle. To accomplish this, female mosquitoes seek vertebrate hosts, land on them and bite. As their eggs mature, they shift attention away from hosts and towards finding sites to lay eggs. We asked whether females were more tuned to visual cues when a host-related signal, carbon dioxide, was present, and further examined the effect of a blood meal, which shifts behaviour to ovipositing. Using a custom, tethered-flight arena that records wing stroke changes while displaying visual cues, we found the presence of carbon dioxide enhances visual attention towards discrete stimuli and improves contrast sensitivity for host-seeking Aedes aegypti mosquitoes. Conversely, intake of a blood meal reverses vertical bar tracking, a stimulus that non-fed females readily follow. This switch in behaviour suggests that having a blood meal modulates visual attention in mosquitoes, a phenomenon that has been described before in olfaction but not in visually driven behaviours.