Search Results (34)

Background: This prospective pilot study included four participants with chronic visual impairment and assessed functional and electrophysiological recovery following visual evoked potential (VEP)-guided auditory biofeedback across diverse etiologies. Low vision affects more than two billion people worldwide and imposes a sustained personal and socioeconomic burden. Conventional rehabilitation emphasizes optical aids and environmental modification without directly stimulating the visual pathway. Emerging evidence indicates that auditory biofeedback based on real-time cortical activity can leverage adult neuroplasticity. Methods: Four men (mean age 58 ± 12 years) with chronic visual impairment attributable to occipital stroke, stage IV macular hole, end-stage open-angle glaucoma, or diabetic maculopathy completed ten 10-min monocular sessions with the Retimax Vision Trainer over three weeks (15 Hz pattern reversal, 90% contrast). Primary end points were best corrected visual acuity (BCVA, ETDRS letters) and P100 amplitude/latency. Fixation stability was recorded with MAIA microperimetry when feasible. A focused PubMed review (2010–2025) mapped current evidence and research gaps. Results: Median BCVA improved by seven letters (IQR 0–15); three of eight eyes gained ≥ 10 letters and none lost vision. Mean P100 amplitude increased from 1.0 ± 1.2 µV to 3.0 ± 1.1 µV, while latency shortened by 3.9 ms. Electrophysiological improvement paralleled behavioural gain irrespective of lesion site. No adverse events occurred. Conclusions: A concise course of VEP-guided auditory biofeedback produced concordant functional and neurophysiological gains across retinal, optic nerve, and cortical pathologies. These pilot data support integration of closed-loop biofeedback into routine low vision care and justify larger sham-controlled trials. Full article

Augmented reality features, such as overlaying information in real time, modifying the projected scene, or dynamically adjusting parameters like contrast, zoom, and brightness, show promise in addressing the specific challenges faced by people with low vision. These tailored solutions enhance their visual experiences. When combined with mobile technology, these features significantly improve the personalization of visual aids and the monitoring of patients with low vision. Retiplus emerges as a personalized visual aid and rehabilitation system, utilizing smart glasses and augmented reality technology for visual aid functions, along with a mobile app for visual assessment, aid customization, and usage monitoring. This wearable system quickly assesses visual conditions, providing deep insights into the visual perception of patients with low vision. Designed to enhance autonomy and quality of life, Retiplus seamlessly integrates into indoor and outdoor environments, enabling the programming of rehabilitation exercises for both static and ambulatory activities at home. In collaboration with specialists, the system meticulously records patient interaction data for subsequent evaluation and feedback. A clinical study involving 30 patients with low vision assessed the effect of Retiplus, analyzing its impact on visual acuity, contrast sensitivity, visual field, and ambulation. The most notable finding was an average increase of 61% in visual field without compromising ambulation safety. Retiplus introduces a new user-centered approach that emphasizes collaboration among a multidisciplinary team for the customization of visual aids, thereby minimizing the gap between the perceptions of low vision specialists and technologists regarding user needs and the actual requirements of users. Full article

This study investigates reading performances and eye movements in individuals with eccentric fixation due to age-related macular degeneration (AMD). Overall, 17 individuals with bilateral AMD (7 males; mean age 77.47 ± 5.96 years) and 17 controls (10 males; mean age 72.18 ± 5.98 years) were assessed for reading visual acuity (VA), reading speed (Minnesota low vision reading chart in Slovene, MNREAD-SI), and near contrast sensitivity (Pelli-Robson). Microperimetry (NIDEK MP-3) was used to evaluate preferential retinal locus (PRL) location and fixation stability. Eye movements were recorded with Tobii Pro-glasses 2 and analyzed for reading duration, saccade amplitude, peak velocity, number of saccades, saccade duration, and fixation duration. Individuals with AMD exhibited significantly reduced reading indices (worse reading VA (p < 0.001), slower reading (p < 0.001), and lower near contrast sensitivity (p < 0.001)). Eye movement analysis revealed prolonged reading duration, longer fixation duration, and an increased number of saccades in individuals with AMD per paragraph. The number of saccades per paragraph was significantly correlated with all measured reading indices. These findings provide insights into reading adaptations in AMD. Simultaneously, the proposed approach in analyzing eye movements puts forward eye trackers as a prospective diagnostic tool in ophthalmology. Full article

Background and Clinical Significance: Central serous chorioretinopathy (CSCR) and hydroxychloroquine (HCQ) retinopathy can both cause outer retinal changes in systemic lupus erythematosus (SLE) patients treated with HCQ and corticosteroids. Differentiating between transient steroid-induced CSCR and irreversible HCQ toxicity is critical to avoid unnecessary discontinuation of essential therapy. Case Presentation: Three female SLE patients (ages 47, 41, and 37) on long-term HCQ (25, 9, and 6 years, respectively) and recent or ongoing low-dose prednisolone presented with unilateral OCT findings, parafoveal or pericentral photoreceptor defects, with the fellow eye unaffected. Review of clinical history and serial imaging revealed transient subretinal fluid in all cases, associated with recent corticosteroid use or dose escalation. Subsequent tapering or cessation of steroids led to resolution of the fluid, and earlier OCT scans confirmed normal outer retinal morphology, indicating that these changes were residual effects of resolved CSCR rather than HCQ toxicity. In Cases 1 and 2, the best-corrected visual acuity (BCVA) in the affected eye declined from 20/22 to 20/40 during the CSCR episode and improved to 20/30 and 20/25, respectively, after subretinal fluid resolution. In Case 3, by contrast, BCVA remained stable at 20/20 throughout the pre-, during-, and post-CSCR periods. Conclusions: Resolved CSCR can mimic HCQ retinopathy. These cases emphasize the importance of detailed medication history, serial multimodal retinal imaging, and comparison with prior and fellow-eye scans to distinguish resolved CSCR from HCQ retinopathy. Such thorough evaluation and careful differential diagnosis help ensure appropriate management—avoiding unnecessary HCQ discontinuation while protecting both ocular and systemic health. Full article

Background/Objectives: Age-related macular degeneration (AMD) is a leading cause of visual impairment in older adults and often coexists with cataracts. The indication of presbyopia-correcting intraocular lenses (IOLs) in these patients remains controversial. This study aimed to evaluate the clinical performance of a non-diffractive extended depth-of-focus (EDOF) IOL (LuxSmart™) compared to a monofocal plus IOL (Tecnis Eyhance™) in cataract patients with early-stage dry AMD. Methods: In this prospective observational study, 41 patients with early-stage AMD underwent bilateral cataract surgery with either LuxSmart™ or Tecnis Eyhance™ IOL implantation, targeting postoperative emmetropia. The eye selected for analysis was the first eye scheduled for surgery. Preoperative and postoperative evaluations included high and low-contrast distance visual acuity, intermediate and near visual acuity, defocus curves, ocular light scatter (halometry), and quality of life assessment (NEI VFQ-25). Postoperative biometric accuracy and refractive outcomes were also analyzed. Results: Both IOLs showed high refractive accuracy, with 100% of eyes within ±0.50 D of target. Postoperative uncorrected distance visual acuity was 0.10 ± 0.06 LogMAR for Eyhance and 0.07 ± 0.02 for LuxSmart (p = 0.06). Low contrast VA at 20% was 0.22 ± 0.11 (Eyhance) and 0.26 ± 0.16 (LuxSmart) (p = 0.49). Depth of focus was approximately 1.75 D for both lenses. Light scatter (LDI) improved postoperatively in both groups with no significant differences (p = 0.54). VFQ-25 scores showed improvement in daily activities, though no changes were observed in driving or mental health domains. Conclusions: Both lenses are safe and effective options for early AMD patients undergoing cataract surgery, providing good functional vision at multiple distances Full article

Low vision is a condition in which a person experiences a significant loss of visual acuity or visual field that ordinary glasses, surgery, or medication cannot correct. Individuals suffering from this condition struggle to perform daily tasks, even when using glasses or contact lenses. In some cases, telescopes are recommended for patients with low vision diagnosis because they could help them improve their quality of life. Therefore, we propose a 3D-printed Galilean telescope for low-vision patients, accessible to both the vulnerable and nonvulnerable sectors of the population, with the advantages that the fabrication time, cost, and weight are considerably reduced. The performance of the 3D-printed Galilean telescope was evaluated by comparing it to an identical N-BK7 glass Galilean telescope design, obtaining a difference of 0.49 lp/mm in optical resolution. Clinical results from a patient with low vision, obtained as part of a proof-of-concept study, showed that the 3D-printed Galilean telescope improved the patient’s visual acuity, increasing it by up to 4 lines on the LEA numbers, from 10/80 to 10/32. Additionally, the 3D telescope enhanced the patient’s contrast sensitivity, improving it from 6 cpd (cycles per degree) level 8 to 18 cpd level 4. Full article

Background: Standard visual acuity (VA) is often preserved in early retinitis pigmentosa (RP), limiting its value as a marker of functional impairment. Alternative measures such as low-luminance deficit (LLD) and low-contrast deficit (LCD) may detect earlier changes in cone function. This study aimed to evaluate the diagnostic utility of these measures in RP patients under photopic and mesopic conditions. Methods: A prospective observational study was conducted on 57 RP patients and 54 age-matched controls. Binocular VA was assessed using ETDRS charts at 100% and 10% contrast under photopic (100 cd/m²) and mesopic (1 cd/m²) conditions. LLD and LCD scores were computed from VA differences across conditions. ROC curve analysis was used to determine diagnostic accuracy. Results: RP patients showed significant VA loss under reduced luminance and contrast (p < 0.001), independent of age. LLD under high contrast was reduced, while LLD under low contrast and LCD (both photopic and mesopic) were significantly higher than in controls. The mesopic LCD demonstrated the highest diagnostic capacity (AUC = 0.87), with a threshold of > 13 ETDRS letters yielding optimal sensitivity and specificity. Unlike standard VA, mesopic LCD correlated with functional symptoms and was unaffected by age. Conclusions: Low-contrast VA under mesopic conditions is a simple, reproducible, and sensitive marker for early visual dysfunction in RP. A difference > 13 ETDRS letters may serve as a clinically relevant threshold for disease monitoring and early detection in retinal dystrophies. Full article

The aim of this study was to evaluate the relationship between visual functions and road traffic accidents (RTAs) by meta-analysis of observational studies. The analysis included all drivers of motor vehicles, regardless of age, and those using private or public transport. Self-reported visual outcomes were excluded. The risk of RTA in patients with reduced visual acuity was observed in commercial drivers in cross-sectional studies (PR 1.54, 95% CI 1.26–1.88), but not in private drivers in cohort (RR 1.04, 95% CI 0.74–1.46) or case–control studies (OR 1.04, 95% CI 0.78–1.40). A non-statistically significant association between colour vision defects and RTA was observed in cross-sectional studies (PR 1.50, 95% CI 0.91–2.45). No evidence was found for an increased risk of accidents in people with reduced stereopsis. In older adults with abnormal contrast sensitivity, a weak risk of RTA was observed in cohort studies. Evidence from low-quality cross-sectional studies suggests an increased risk of RTAs among commercial drivers with reduced visual acuity. The few case–control and cohort studies identified did not show an association between accident occurrence and visual function. Attention needs to be paid to this issue to facilitate the conduct of high-quality research that can support the development of road safety policies. Full article

Objectives: To evaluate the clinical performance and optical quality of a non-diffractive extended-depth-of-focus (EDOF) intraocular lens (IOL), Asqelio™ EDOF (models ETLIO130C/ETPIO130C), in patients undergoing cataract surgery or refractive lensectomy. Methods: This prospective observational, case-control study included patients bilaterally implanted with either the Asqelio™ EDOF IOL (Study Group) or the spherical monofocal TECNIS^® 1-Piece ZCB00 IOL (Control Group). The postoperative outcomes—at 3 months after surgery—included visual acuities at multiple distances, refraction, contrast sensitivity, the optical scatter index (OSI), wavefront aberrations, and patient-reported outcomes (Catquest-9SF and a quality-of-vision questionnaire). Results: Twenty-three patients (46 eyes) in the Asqelio™ EDOF group and 17 patients (34 eyes) in the monofocal control group were enrolled. Postoperatively, 91% of eyes in the EDOF group were within ±0.50 D of the intended spherical equivalent. The binocular uncorrected distance, intermediate, and near visual acuities were 0.00 ± 0.09, 0.13 ± 0.12, and 0.32 ± 0.15 logMAR, respectively. Contrast sensitivity and OSI values were similar between the study and control groups (p > 0.05). Higher-order aberrations were significantly lower in the EDOF group (p < 0.001), but values in both groups were clinically low. No adverse events were reported. Most patients expressed high satisfaction and reported few visual disturbances. Conclusions: The Asqelio™ EDOF IOL provided good refractive predictability, effective uncorrected vision across distance and intermediate ranges, and high patient satisfaction. Contrast sensitivity and optical scatter were comparable to monofocal implants. This lens can be considered a valuable option for patients seeking an extended range of functional vision with minimal side effects. Full article

Background: Amblyopia is a neurodevelopmental disorder of vision, commonly caused by strabismus or anisometropia during early childhood. While studies demonstrated that perceptual learning improves visual acuity and stereopsis in adults with amblyopia, accompanying changes in visual cortical function remain unclear. Methods: We measured functional magnetic resonance imaging (fMRI) responses before and after perceptual learning in seven adults with amblyopia. Our learning tasks involved dichoptic high-attention-demand tasks that avoided V1 function-related tasks and required high-level cortical functions (e.g., intraparietal sulcus) to train the amblyopic eye. Results: Perceptual learning induced low-level visual cortical function changes, which were strongly associated with the etiology of amblyopia and visual function improvements. Anisometropic amblyopes showed functional improvements across all regions of interest (ROIs: V1, V2, V3, V3A, and hV4), along with improvements in visual acuity and stereoacuity. In contrast, strabismic amblyopes showed robust improvements in visual cortical functions only in individuals who experienced significant gains in visual acuity and stereoacuity. Notably, improvements in V1 functions were significantly correlated with the magnitude of visual acuity and stereoacuity improvements when combining both anisometropic and strabismic amblyopes. Conclusions: Our findings provide evidence that learning occurs in both high-level and low-level cortical processes. Our study suggests that early intervention to correct eye alignment (e.g., strabismus surgery) is critical for restoring both visual and cortical functions in strabismic amblyopia. Full article

Corneal ectasias, including keratoconus (KC), pellucid marginal degeneration (PMD), and post-LASIK ectasia, poses significant visual rehabilitation challenges due to the resultant irregular astigmatism, myopia, and higher-order aberrations (HOAs). These conditions often resist traditional corrective methods, necessitating advanced optical solutions. Scleral lenses (SLs) have emerged as a primary non-surgical option for managing these complex corneal irregularities. SLs form a smooth optical interface by forming a tear-filled chamber between the lens and the cornea, effectively mitigating HOAs and improving both high-contrast and low-contrast visual acuity (VA). This review evaluates the efficacy of SLs in enhancing VA and reducing aberrations in patients with corneal ectasia. It also explores the technological advancements in SLs, such as profilometry and wavefront-guided systems, which enable more precise and customized lens fittings by accurately mapping the eye’s surface and addressing specific visual aberrations. The current body of evidence demonstrates that custom SLs significantly improve visual outcomes across various ectatic conditions, offering superior performance compared to conventional correction methods. However, challenges such as the complexity of fitting and the need for precise alignment remain. Ongoing innovations in SL technology and customization are likely to further enhance their clinical utility, solidifying their role as an indispensable tool in the management of corneal ectasias. Full article

Objectives: Achromatopsia (ACHM) is a rare autosomal, recessively inherited disease that is characterized by cone dysfunction, for which several gene therapies are currently on trial. The aim of this study was to find correlations between the morphological macular changes identified using optical coherence tomography (OCT) and some visual functional parameters. Visual acuity (VA), contrast sensitivity (CS), and macular sensitivity obtained by means of microperimetry were assessed. Methods: Adolescents with ACHM underwent macular microperimetry (S-MAIA device) in mesopic condition, macular OCT, best corrected visual acuity (BCVA), low luminance visual acuity (LLVA), near vision acuity (NVA), and CS measurement. Results: Eight patients (15 eyes) with ACHM were analyzed. The mean age was 17 ± 2.7 years, and genetic variants involved the CNGA3 gene (37.5%) and CNGB3 gene (62.5%). OCT staging significantly correlated with microperimetry sensitivity parameters, namely the sensitivity of the central foveal point (p = 0.0286) and of the first and second perifoveal rings (p = 0.0008 and p = 0.0014, respectively). No correlations were found between OCT staging and VA measurements, nor with CS value. Conclusions: Among the extensive evaluated visual function tests, only microperimetry sensitivity showed a correlation with morphological macular changes identified at OCT. Microperimetry sensitivity may thus represent a useful visual function tool in natural ACHM history studies considering the upcoming research on gene therapies for the treatment of ACHM. Full article

Background: Three computerized tests were designed to evaluate visual function, alertness, and visuocognitive integration under three different lighting conditions (white, red, and blue lighting). Methods: Three computerized tests were designed and programmed using the experimental design software PsychoPy version 2023.2.2. Test 1 evaluated visual acuity (VA), Test 2 assessed contrast sensitivity, and Test 3 measured alertness. This study was conducted on 53 young subjects who performed three computerized tests after adapting to each of the three different lighting conditions. A baseline aberrometric measurement was taken before and after the tests for each lighting condition. Measurements of accuracy and reaction time were taken for each test, along with total, high-, and low-order aberration values for each situation. Results: Statistically significant differences (p ≤ 0.05) were found among the different lighting conditions across the three tests, with white lighting yielding better performance in Test 1 and Test 3. Additionally, the aberrometric analysis revealed significant differences (p ≤ 0.05), with the baseline measurement being more myopic. Conclusions: White lighting produced the best VA results and faster reaction times, whereas red lighting had poorer VA effects. These findings suggest that different lighting conditions induce changes in vision and alertness, although further research is needed to understand the underlying causes. Full article

Spatial aspects of visual performance are usually evaluated through visual acuity charts and contrast sensitivity (CS) tests. CS tests are generated by vanishing the contrast level of the visual charts. However, the quality of retinal images can be affected by both ocular aberrations and scattering effects and none of those factors are incorporated as parameters in visual tests in clinical practice. We propose a new computational methodology to generate visual acuity charts affected by ocular scattering effects. The generation of glare effects on the visual tests is reached by combining an ocular straylight meter methodology with the Commission Internationale de l’Eclairage’s (CIE) general disability glare formula. A new function for retinal contrast assessment is proposed, the subjective straylight function (SSF), which provides the maximum tolerance to the perception of straylight in an observed visual acuity test. Once the SSF is obtained, the subjective straylight index (SSI) is defined as the area under the SSF curve. Results report the normal values of the SSI in a population of 30 young healthy subjects (19 ± 1 years old), a peak centered at SSI = 0.46 of a normal distribution was found. SSI was also evaluated as a function of both spatial and temporal aspects of vision. Ocular wavefront measures revealed a statistical correlation of the SSI with defocus and trefoil terms. In addition, the time recovery (TR) after induced total disability glare and the SSI were related; in particular, the higher the RT, the greater the SSI value for high- and mid-contrast levels of the visual test. No relationships were found for low contrast visual targets. To conclude, a new computational method for retinal contrast assessment as a function of ocular straylight was proposed as a complementary subjective test for visual function performance. Full article

This prospective, double-masked, contralateral study aimed to analyze and compare daytime changes in pre-lens tear film (PLTF) stability and optical quality in symptomatic subjects wearing two contact lenses (CL). A secondary goal was to assess the performance of the PLTF by using dynamic topography techniques and analyzing surface asymmetry and irregularity indexes (SAI and SRI, respectively). Measurements were conducted on 20 symptomatic subjects (OSDI score > 13). Participants were fitted contralaterally and randomly with spherical Delefilcon A and Stenfilcon A CLs and underwent a series of measurements over 3 consecutive days: three in the morning (after 1–2 h of CL wear) and three in the afternoon (after 7–9 h of CL wear). High- and low-contrast visual acuity (HCVA and LCVA, respectively), pre-lens NIBUT, and dynamic topography were assessed. The contralateral fit of the two lenses allowed a direct and better comparison between them since they were exposed to the same conditions during the day. Consequently, both lenses demonstrated similar performance in HCVA, LCVA, and PLTF stability, with no statistically significant differences between them, although some fluctuations were observed throughout the day. Dynamic topography proved sensitive in evaluating temporal changes in the PLTF. The SRI index showed greater sensitivity to topographic changes due to lacrimal destabilization, making it potentially valuable for evaluating dry eye patients. Full article