Search Results (98)

Background: Neuromyelitis optica spectrum disorder (NMOSD) causes severe optic nerve (ON) inflammation and vision loss. Current treatments remain limited, prompting exploration of new therapeutic strategies. This study evaluated the efficacy of ITRI-E-(S)4046 (ITRI-ES), a dual ROCK1/2 and MYLK4 kinase inhibitor, in a rat model of NMOSD optic neuritis. Methods: NMOSD-like optic neuritis was induced in rats by applying NMOSD patient serum-soaked sponges around the ON. Rats received intravitreal injections of either 0.2% ITRI-ES, phosphate-buffered saline (PBS), or intraperitoneal methylprednisolone (MP). Visual function was assessed using flash visual-evoked potentials (fVEP). Retinal ganglion cell (RGC) survival and apoptosis were quantified using FluoroGold retrograde labeling and TUNEL assay. ON inflammation and demyelination were evaluated via immunohistochemistry and Western blot analysis of aquaporin-4 (AQP4), myelin basic protein (MBP), glial fibrillary acidic protein (GFAP), and inflammatory markers. Results: ITRI-ES significantly preserved visual function, restoring fVEP amplitudes (~36 μV vs. ~21 μV in PBS-treated, p < 0.05) and RGC density (~85% of normal vs. ~37% PBS). RGC apoptosis was reduced (~2.3-fold lower vs. PBS, p < 0.05). PBS-treated rats showed decreased AQP4 and MBP (2.5–2.8-fold vs. sham) and increased GFAP (2.8-fold). ITRI-ES maintained higher AQP4 (~3.5-fold) and MBP (~1.5-fold) levels, suppressed GFAP (~5.5-fold vs. PBS), reduced NF-κB, IL-1β, TNF-α, microglia activation, and macrophage infiltration, and increased anti-inflammatory Arg1 and CD206 markers (~3-fold vs. PBS). Conclusions: ITRI-ES alleviates optic nerve inflammation, preserves retinal integrity, and maintains visual function in NMOSD-associated optic neuritis, underscoring kinase inhibition as a promising therapeutic strategy. Full article

Visual impairments pose a significant global health challenge, and visual electrophysiological (EP) acquisition plays a pivotal role in diagnosing ophthalmic diseases. However, traditional electrodes still encounter limitations such as inadequate mechanical adaptability and reusability. This study proposes a stretchable and transparent electrode (STE) consisting of a conductive paste/indium tin oxide layer on a polymethyl methacrylate substrate. Leveraging an island–bridge design, the STE renders reliable performance even after being subjected to 1000 cycles of 25% lateral strain and 18% diagonal strain, exhibiting exceptional mechanical flexibility and realizing seamless attachment to soft tissue. Furthermore, optimized conductive paste layer thickness yields a signal-to-noise ratio comparable to commercial electrodes, achieving equivalent performance to Ag/AgCl electrodes in electroretinogram (ERG), electrooculography (EOG), and visual evoked potential (VEP) acquisition. The STE’s mechanical suitability and inconspicuous features hold significant potential for widespread clinical adoption in ophthalmic diagnostics and personalized eye healthcare, offering improved comfort, reusability, and diagnostic precision. Full article

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

Background: Optic neuritis (ON) is a common manifestation of multiple sclerosis (MS), serving as a clinical window into central nervous system demyelination. Optical coherence tomography (OCT) and visual evoked potentials (VEPs) are complementary non-invasive tools for assessing structural and functional damage to the visual pathway. The objective of this paper is to evaluate correlations between OCT and VEP parameters in MS patients with and without a history of ON and assess their relationship with disease duration and disability (EDSS). Methods: This cross-sectional study included 54 eyes from 27 relapsing–remitting MS patients. OCT was used to measure circumpapillary and the temporal peripapillary retinal nerve fiber layer (pRNFL) and the foveal/parafoveal ganglion cell-inner plexiform layer (GCIPL) thickness. VEPs assessed P100 latency and amplitude. Patients were grouped by ON history. Results: Eyes without ON showed a significantly greater circumpapillary pRNFL thickness (mean difference: 18.27 ± 5.33 µm, p = 0.001), temporal pRNFL thickness (15.71 ± 5.49 µm, p = 0.006), and parafoveal GCIPL thickness (12.85 ± 5.3 µm, p = 0.019) compared to ON eyes. p100 latency was shorter and the amplitude was higher in NON eyes, but without statistical significance. Strong negative correlations were found between OCT thickness and EDSS and disease duration. p100 latency correlated negatively with OCT parameters, while amplitude showed a positive correlation with pRNFL thickness in ON eyes. Conclusions: OCT parameters, particularly pRNFL and GCIPL thickness, correlate with functional and clinical markers of MS. Combined OCT–VEP evaluation enhances the assessment of neurodegeneration and disease progression. Full article

Background: Leber’s hereditary optic neuropathy (LHON) is the most common mitochondrial disorder and an inherited optic neuropathy. Recently, two different LHON inheritance types have been discovered: mitochondrially inherited LHON (mtLHON) and autosomal recessive LHON (arLHON). Our case report is the first diagnosed case of arLHON in a patient of Lithuanian descent and confirms the DnaJ Heat Shock Protein Family (Hsp40) Member C30 (DNAJC30) c.152A>G p.(Tyr51Cys) founder variant. Case Presentation: A 34-year-old Lithuanian man complained of headache and sudden, painless loss of central vision in his right eye. On examination, the visual acuity of the right and left eyes was 0.1 and 1.0, respectively. Visual-field examination revealed a central scotoma in the right eye, and visual evoked potentials (VEPs) showed prolonged latency in both eyes. Optical coherence tomography showed thickening of the retinal nerve fiber layer in the upper quadrant of the optic disk in the left eye. Magnetic resonance imaging of the head showed evidence of optic nerve inflammation in the right eye. Blood tests were within normal range and showed no signs of inflammation. Retrobulbar neuritis of the right eye was suspected, and the patient was treated with steroids, which did not improve visual acuity. He later developed visual loss in the left eye as well. A genetic origin of the optic neuropathy was suspected, and a complete mitochondrial DNA analysis was performed, but it did not reveal any pathologic mutations. Over time, the visual acuity of both eyes slowly deteriorated, and the retinal nerve fiber layer (RNFL) thinning of the optic disks progressed. A multidisciplinary team of specialists concluded that vasculitis or infectious disease was unlikely to be the cause of the vision loss, and a genetic cause for the disease was still suspected, although a first-stage genetic test did not yield the diagnosis. Thirty-three months after disease onset, whole-exome sequencing revealed a pathogenic variant in the DNAJC30 gene, leading to the diagnosis of arLHON. Treatment with Idebenone was started 35 months after the onset of the disease, resulting in no significant worsening of the patient’s condition. Conclusion: This case highlights the importance of considering arLHON as a possible diagnosis for patients with optic neuropathy, because the phenotype of arLHON appears to be identical to that of mtLHON and cannot be distinguished by clinicians. Full article

Background: Arachnoid cysts are typically benign and asymptomatic, but large cysts can exert a mass effect on adjacent neural structures. Based on the available literature, no cases of cortical visual impairment (CVI) in an adolescent caused by posterior fossa arachnoid cysts have been reported. Case presentation: We report the case of a previously healthy 16-year-old girl who presented with sudden and rapidly progressive bilateral visual loss due to a large retrocerebellar arachnoid cyst. She reported blurred vision, tunnel vision-like, and decreased visual acuity. Although neuro-ophthalmologic and imaging workup revealed no damage to the anterior visual pathways, she exhibited progressive visual decline. Functional tests confirmed bilateral cortical visual impairment: pattern-reversal visual evoked potentials (VEPs) showed preserved and symmetric P100 latencies and amplitudes, while automated perimetry revealed bilateral concentric visual field constriction with preserved central islands. Following cystoperitoneal drainage, her vision rapidly and completely recovered. Conclusions: To the best of our knowledge, this is the first reported case of reversible CVI in an adolescent caused by a posterior fossa arachnoid cyst without intracranial pressure (ICP) elevation or optic nerve involvement, and with tunnel vision-like. Our findings emphasize the role of posterior fossa lesions in visual dysfunction and highlight the potential reversibility of cortical visual loss when timely decompression is achieved. This case underscores the importance of including posterior fossa lesions in the differential diagnosis of unexplained bilateral visual loss, even in the absence of elevated intracranial pressure or anterior visual pathway involvement. Full article

Objectives: To elucidate the influence of eye selection criteria (ESC) on the reliability of biomarkers in diagnosis and prediction using pre-surgical parameters, assessments were undertaken as the subject of analysis. Methods: Pituitary macroadenoma (PMA) diagnosis and postsurgical visual function recovery biomarker analysis was used as the subject to illustrate the point. Six datasets (right, left, best, worst, random and both eyes), derived from a longitudinal study that involved 42 PMA patients and age-matched healthy volunteers, were generated. A comparison of the diagnostic efficacies of the amplitude of pattern visual evoked potentials (pVEP) and bi-nasal sector thickness in the ganglion cells complex plus the inner plexiform layer was performed using ESC. Afterwards, multivariate models for PMA diagnosis and the prediction of postsurgical visual function recovery, using Stable Sparse Biomarkers Detection methodology, were developed. A comprehensive evaluation was performed once for controls and in pre-surgical PMA patients at 3 and 12 months after transsphenoidal tumor removal. Results: The proposed biomarkers displayed specificity and sensibility ≥ 0.74 and AUC ≥ 0.87. The diagnostic values derived were ESC-dependent. All the prediction models had accuracies over 0.96, and the proposed biomarkers had stability ≥ 99% and the highest β values. Conclusions: Although the diagnostic values of the proposed biomarkers are affected by ESC, they exhibit equal accuracy for the same eye. Worse eye data represent the best choice for the analysis. Further studies are needed to validate the models for use in the prediction of the 12-month postsurgical restoration of parvocellular traffic. Full article

Background: Visual evoked potentials (VEPs) are used to detect chiasmal misrouting associated with albinism. However, VEPs are only performed in specialist centres and typically have long waiting lists. The portable electrophysiology device RETeval^® shows promise as a clinical screening tool across a range of ophthalmic conditions. Here, we explore its utility in detecting chiasmal abnormalities associated with albinism. Methods: Flash VEPs were recorded on the RETeval^® and by standard ISCEV techniques for 27 patients with suspected albinism and 40 control patients as part of routine appointments. We retrospectively investigated the agreeability between the two methods. The amplitude/latency of the main component was measured for standard VEPs whilst a correlation value of interhemispheric difference was calculated for the RETeval^® data. Results: We demonstrate a significant difference between albinism patients and controls (p < 0.001) with respect to the interhemispheric difference identified by the RETeval^®. By applying a threshold of 0.001865 to the correlation value, the RETeval^® detected chiasmal misrouting in all 27 patients with albinism and had 97% agreeability to standard testing. Conclusions: This study shows the potential of using the RETeval^® as a clinical tool for the diagnosis of chiasmal anomalies in albinism. The RETeval^® has significant time/cost savings which could hasten diagnoses. Full article

(1) Background: Brain–computer interfaces (BCIs) enable direct communication between the brain and external devices using electroencephalography (EEG) signals, offering potential applications in assistive technology and neurorehabilitation. Code-modulated visual evoked potential (cVEP)-based BCIs employ code-pattern-based stimulation to evoke neural responses, which can then be classified to infer user intent. While increasing the number of EEG electrodes across the visual cortex enhances classification accuracy, it simultaneously reduces user comfort and increases setup complexity, duration, and hardware costs. (2) Methods: This online BCI study, involving thirty-eight able-bodied participants, investigated how reducing the electrode count from 16 to 6 affected performance. Three experimental conditions were tested: a baseline 16-electrode configuration, a reduced 6-electrode setup without retraining, and a reduced 6-electrode setup with retraining. (3) Results: Our results indicate that, on average, performance declines with fewer electrodes; nonetheless, retraining restored near-baseline mean Information Transfer Rate (ITR) and accuracy for those participants for whom the system remained functional. The results reveal that for a substantial number of participants, the classification pipeline fails after electrode removal, highlighting individual differences in the cVEP response characteristics or inherent limitations of the classification approach. (4) Conclusions: Ultimately, this suggests that minimal cVEP-BCI electrode setups capable of reliably functioning across all users might only be feasible through other, more flexible classification methods that can account for individual differences. These findings aim to serve as a guideline for what is currently achievable with this common cVEP paradigm and to highlight where future research should focus in order to move closer to a practical and user-friendly system. Full article

Background: The diagnosis of multiple sclerosis (MS) relies on identifying neurological signs and symptoms, supported by evidence of central nervous system (CNS) dissemination of lesions across time and space. The visual pathway is commonly involved in MS, with a frequent involvement of optic neuritis (ON) episodes. Our study aims to assess the relationship between neuronal damage and optic nerve demyelination by analyzing the latency and amplitude of the p100 wave complex using visual evoked potentials (VEPs). Methods: We conducted a retrospective longitudinal study, analyzing VEP records of 15 patients with recurrent remissive MS at baseline, 5, 10, 15, and 19 years. Results: In 30 eyes we observed an increase in p100 wave latency at 5-years by 14.35 ± 4.47 ms (p = 0.003), at 10-years by 19.26 ± 4.87 ms (p < 0.0005) and a decrease in amplitude by 2.29 ± 0.52 mV (p < 0.0005) when comparing to baseline values. At 15-years, 24 eyes presented an increase in latency of 31.39 ± 7.8 ms (p = 0.001) and a decrease in amplitude of 2.51 ± 0.6 mV (p < 0.0005) compared to baseline, while at 19-years, 10 eyes presented an increase in p100 wave latency of 53.45 ± 18.42 ms (p = 0.018) and a further decrease in amplitude of 4.06 ± 1.32 mV (p = 0.014). We found correlations between the p100 wave latency and amplitude at baseline, 15-year, and 19-year follow-ups, increasing from a low negative (r = −0.43) to medium negative (r = −0.502) and finally high negative (r = −0.906) correlation. Conclusions: VEPs have long been acknowledged for their ability to detect both clinical and subclinical lesions in MS cases. Our study offers new insight into the relationship between demyelination and axonal degeneration observed when analyzing the latency and amplitude of the p100 wave complex during VEP in a longitudinal analysis. Full article

Background/Aim: Among NF1-dependent tumors, the most common are optic pathway gliomas (OPGs). The objective of this study was the retrospective analysis of the course, indications for treatment, and effects of therapy for NF1-OPGs. Patients and Methods: We analyzed demographics, clinical and genetic data, imaging and ophthalmological parameters, their impact on therapeutic decisions, and the effectiveness of the therapy in 92 patients. Results: OPGs were unilateral in 55.4% of patients and bilateral in 44.6%. Post-contrast enhancement in MRI was observed in 67.4%. Oncological treatment was required in 16.3% of patients with median age 3.8 years. Factors significant in multivariate analysis contributing to the need of oncological treatment were: amblyopia and proptosis. Factors contributing to amblyopia were: strabismus, proptosis, co-occurrence of epilepsy, bilateral OPGs, and thickness of the optic nerve ≥ 8 mm. The first line of oncological treatment included vincristine + carboplatin or monotherapy with vinblastine. The use of subsequent lines of oncological treatment was necessary in 46.7% patients. Conclusions: The following conclusions, suggest modification of the approach in the management of patients with NF1-OPG, summarize the presented study: (1) perform the first MRI after the age of 1 year, (2) reduce the frequency of follow-up scans in the first year of observation in patients with isolated involvement of intraocular and/or intraorbital segments of the optic nerve, (3) refrain from administering contrast during control MRI examinations of the orbits after OPG diagnosis; (4) in patients with co-occurring psychomotor delay or treated with antiepileptic drugs, do not make decisions about oncological therapy when visual acuity deterioration is observed, without progression in optical coherence tomography (OCT), visual evoked potentials (VEP), and MRI. Full article

Nowadays, brain–computer interface (BCI) systems are frequently used to connect individuals who have lost their mobility with the outside world. These BCI systems enable individuals to control external devices using brain signals. However, these systems have certain disadvantages for users. This paper proposes a novel approach to minimize the disadvantages of visual stimuli on the eye health of system users in BCI systems employing visual evoked potential (VEP) and P300 methods. The approach employs moving objects with different trajectories instead of visual stimuli. It uses a light-emitting diode (LED) with a frequency of 7 Hz as a condition for the BCI system to be active. The LED is assigned to the system to prevent it from being triggered by any involuntary or independent eye movements of the user. Thus, the system user will be able to use a safe BCI system with a single visual stimulus that blinks on the side without needing to focus on any visual stimulus through moving balls. Data were recorded in two phases: when the LED was on and when the LED was off. The recorded data were processed using a Butterworth filter and the power spectral density (PSD) method. In the first classification phase, which was performed for the system to detect the LED in the background, the highest accuracy rate of 99.57% was achieved with the random forest (RF) classification algorithm. In the second classification phase, which involves classifying moving objects within the proposed approach, the highest accuracy rate of 97.89% and an information transfer rate (ITR) value of 36.75 (bits/min) were achieved using the RF classifier. Full article

Background/Objectives: Cochlear implantation is the primary treatment for severe-to-profound hearing loss, yet outcomes vary significantly among recipients. While visual–auditory cross-modal reorganization has been identified as a contributing factor to this variability, its impact in early-implanted children remains unclear. To address this knowledge gap, we investigated visual processing and its relationship with auditory outcomes in children who received early bilateral cochlear implants. Methods: To examine potential cross-modal reorganization, we recorded visual evoked potentials (VEPs) in response to pattern-reversal stimuli in 25 children with cochlear implants (CIs) (mean implantation age: 1.44 years) and 28 age-matched normal-hearing (NH) controls. Analysis focused on both the occipital region of interest (ROI: O1, OZ, and O2 electrode sites) and right temporal ROI, examining VEP components and their correlation with speech perception outcomes. Results: Unlike previous studies in later-implanted children, the overall occipital ROI showed no significant differences between groups. However, the left occipital electrode (O1) revealed reduced P1 amplitudes and delayed N1 latencies in CI users. Importantly, O1 N1 latency negatively correlated with speech-in-noise performance (r = −0.318; p = 0.02). The right temporal region showed no significant differences in VEP N1 between groups and no correlation with speech performance in CI users. Conclusions: Early bilateral cochlear implantation appears to preserve global visual processing, suggesting minimal maladaptive reorganization. However, subtle alterations in left occipital visual processing may influence auditory outcomes, highlighting the importance of early intervention and the complex nature of sensory integration in this population. Full article

Nonarteritic anterior ischemic optic neuropathy (NAION) is an ischemic lesion of the anterior optic nerve (ON), currently untreatable due to the length of time from symptom onset until treatment. We evaluated angiotensin-(1-7) (Ang-(1-7)): the MAS1-receptor ligand, as a possible NAION treatment using the rodent NAION model (rNAION). Long-Evans rats were unilaterally rNAION-induced. One-day post-induction, lesion severity was quantified via optic nerve head (ONH) edema using spectral domain optical coherence tomography. Animals meeting rNAION induction criteria were randomized into (1) Subcutaneous Ang-(1-7) infusion for 28 days and (2) Vehicle. Visual function was assessed using both visual acuity and flash visual evoked potentials (fVEP). Tissues were collected >30d and RGC neurons were quantified by stereology. ONs were histologically examined for inflammation. Ang-(1-7) improved post-rNAION visual function. Ang-(1-7)-treated animals showed improved visual acuity (ANCOVA: p = 0.0084) and improved fVEP amplitudes (ANCOVA: p = 0.0378) vs vehicle controls. The relative degree of improvement correlated with ONH edema severity. Treated animals showed trends towards increased RGC survival, and reduced optic nerve inflammatory cell infiltration. Ang-(1-7) is the first agent effective ≥1 day after rNAION induction. Ang-(1-7) type agonists may be useful in improving long-term function and neuronal survival in clinical NAION and other forms of white matter ischemia. Full article

A macular hole is a defect of the neurosensory retina at the fovea. Post-traumatic holes can occur immediately after blunt trauma, causing severe non-penetrating retinal contusion or after sudden detachment of the vitreous from the retina. Post-traumatic macular holes can close spontaneously or may require vitreoretinal surgery. This paper aims to present the case of an 11-year-old boy with a macular hole following a ball injury. The child reported deterioration of visual acuity. Ophthalmic examination, ocular ultrasound, optical coherence tomography (OCT), perimetry, and a pattern visual evoked potential (VEP) test were performed. On the day of injury, the visual acuity of the right eye was 0.04 and intraocular pressure was 28 mmHg; the eyelid skin was reddened, and superficial conjunctival injection was observed. A fundus examination revealed oedema, pre-retinal haemorrhages, and a macular hole; peripheral retinal oedema in the superior temporal quadrant with pre-retinal haemorrhages was also seen. At the follow-up appointment scheduled 5 months following hospital discharge, visual acuity of the right eye was 0.3 and intraocular pressure was 20 mmHg. Follow-up OCT images of the OD macula were comparable to the findings obtained on the day of hospital discharge, i.e., 10 days after blunt trauma to the right eye. The left-eye OCT did not reveal any abnormalities. Full article