Residual Visual Function Research Articles

Pre- and postoperative OCT features and surgical outcomes of advanced retinitis pigmentosa with macular hole: case series and literature review

BackgroundMacular hole (MH) is a rare complication of retinitis pigmentosa (RP) and has an adverse impact on residual visual function. At present, the underlying mechanisms are not fully understood and surgical experience is limited.MethodsWe reviewed the medical records and optical coherence tomography (OCT) scans in a cohort of eight eyes of seven RP patients with MH in order to report their OCT features and vitreoretinal surgical prognosis.ResultsThis study includes four lamellar macular holes (LMHs) and four full-thickness macular holes (FTMHs). Pre-operative OCT revealed other macular abnormalities in all eyes, such as epiretinal membrane (ERM), cystoid macular edema (CME), lamellar hole-associated epiretinal proliferation (LHEP) and vitreoretinal traction. MH progression and subjective vision worsening were noted in one LMH eye during a seven-month follow-up. All holes closed after vitrectomy with internal limiting membrane (ILM) peeling. At final follow-up, one eye had improved vision and seven eyes remained stable compared to baseline.ConclusionsThe occurrence of MH in RP is accompanied by various imaging characteristics, such as ERM, CME and LHEP, suggesting a multifactorial pathogenesis. Considering poor vision in most RP patients with potentially progressive MH, surgery appears to be effective in maintaining or improving the central vision in a period of time. Thus, vitrectomy should be performed as soon as possible and flap-assisted techniques or episcleral surgeries are needed for some special cases.

Glaucoma Rehabilitation using ElectricAI Transcranial Stimulation (GREAT)—study protocol for randomized controlled trial using combined perceptual learning and transcranial electrical stimulation for vision enhancement

BackgroundGlaucoma patients with irreversible visual field loss often experience decreased quality of life, impaired mobility, and mental health challenges. Perceptual learning (PL) and transcranial electrical stimulation (tES) have emerged as promising interventions for vision rehabilitation, showing potential in restoring residual visual functions. The Glaucoma Rehabilitation using ElectricAI Transcranial stimulation (GREAT) project aims to investigate whether combining PL and tES is more effective than using either method alone in maximizing the visual function of glaucoma patients. Additionally, the study will assess the impact of these interventions on brain neural activity, blood biomarkers, mobility, mental health, quality of life, and fear of falling.MethodsThe study employs a three-arm, double-blind, randomized, superiority-controlled design. Participants are randomly allocated in a 1:1:1 ratio to one of three groups receiving: (1) real PL and real tES, (2) real PL and sham tES, and (3) placebo PL and sham tES. Each participant undergoes 10 sessions per block (~ 1 h each), with a total of three blocks. Assessments are conducted at six time points: baseline, interim 1, interim 2, post-intervention, 1-month post-intervention, and 2-month post-intervention. The primary outcome is the mean deviation of the 24-2 visual field measured by the Humphrey visual field analyzer. Secondary outcomes include detection rate in the suprathreshold visual field, balance and gait functions, and electrophysiological and biological responses. This study also investigates changes in neurotransmitter metabolism, biomarkers, self-perceived quality of life, and psychological status before and after the intervention.DiscussionThe GREAT project is the first study to assess the effectiveness of PL and tES in the rehabilitation of glaucoma. Our findings will offer comprehensive assessments of the impact of these treatments on a wide range of brain and vision-related metrics including visual field, neural activity, biomarkers, mobility, mental health, fear of falling, and quality of life.Trial registrationClinicalTrials.gov NCT05874258. Registered on May 15, 2023.

DISCREPANCY BETWEEN FUNDUS AUTOFLUORESCENCE ABNORMALITY AND VISUAL FIELD LOSS IN BIETTI CRYSTALLINE DYSTROPHY.

The aim of this study was to explore the potential benefits of retinal pigment epithelium replacement therapy in patients with Bietti crystalline dystrophy (BCD) by assessing the disease pathology with the distinctive relationship between fundus autofluorescence (FAF) abnormality and visual field defect. Sixteen eyes from 16 patients with BCD and 16 eyes from 16 patients with RHO-associated retinitis pigmentosa were included. Fundus autofluorescence, optical coherence tomography, and Goldmann perimetry results were retrospectively reviewed and assessed using image analyses. In patients with BCD, the FAF abnormality area was not correlated with the overall visual field defect area and median overall visual field defect area (57.5%) was smaller than FAF abnormality area (98.5%). By contrast, the ellipsoid zone width was significantly correlated with the central visual field area (r = 0.806, P < 0.001). In patients with RHO-associated retinitis pigmentosa, the FAF abnormality area and ellipsoid zone width were significantly correlated with the overall visual field defect area (r = 0.833, P < 0.001) and central visual field area (r = 0.887, P < 0.001), respectively. The FAF abnormality shown in patients with BCD involves retinal pigment epithelium degeneration without complete loss of photoreceptors or visual function. These results suggest that patients with BCD are good candidates for retinal pigment epithelium replacement therapy for preservation of residual visual function.

TRNS boosts visual perceptual learning in participants with bilateral macular degeneration.

Perceptual learning (PL) has shown promise in enhancing residual visual functions in patients with age-related macular degeneration (MD), however it requires prolonged training and evidence of generalization to untrained visual functions is limited. Recent studies suggest that combining transcranial random noise stimulation (tRNS) with perceptual learning produces faster and larger visual improvements in participants with normal vision. Thus, this approach might hold the key to improve PL effects in MD. To test this, we trained two groups of MD participants on a contrast detection task with (n = 5) or without (n = 7) concomitant occipital tRNS. The training consisted of a lateral masking paradigm in which the participant had to detect a central low contrast Gabor target. Transfer tasks, including contrast sensitivity, near and far visual acuity, and visual crowding, were measured at pre-, mid and post-tests. Combining tRNS and perceptual learning led to greater improvements in the trained task, evidenced by a larger increment in contrast sensitivity and reduced inhibition at the shortest target to flankers' distance. The overall amount of transfer was similar between the two groups. These results suggest that coupling tRNS and perceptual learning has promising potential applications as a clinical rehabilitation strategy to improve vision in MD patients.

Correlation between Residual Sensitivity in the Central Inferior Nasal Visual Field and Visual Function in Chronic Leber Hereditary Optic Neuropathy Patients

Introduction: Leber hereditary optic neuropathy (LHON) is a maternally inherited, acute or subacute, optic neuropathy. The typical symptoms include reduced visual acuity and central scotoma. Despite the presence of deep central scotoma, some patients with LHON are able to perform daily activities. This study aimed to investigate the correlation between the residual visual field and visual acuity, critical flicker frequency, and fixation ellipse in patients with chronic LHON. Methods: Residual visual function (defined as sensitivity points where patients sensed the size V stimulus) of both eyes was evaluated in 10 patients with LHON carrying the m.11778 mitochondrial DNA mutation and with median age of onset and disease duration of 29 and 16.5 years, respectively. The central visual field was measured as static perimetry using the Humphrey visual field testing 30-2 program with the size III or V stimulus. Moreover, best-corrected visual acuity, critical flicker frequency, and the correlation between fixation ellipse and residual central visual fields were determined. The analysis was performed through a linear mixed-effects model. Results: The residual visual sensitivity in the inferior nasal visual field was significantly correlated with the logMAR (p < 0.05). The fixation ellipse fell within the residual visual field region with higher sensitivity. Conclusions: Patients with chronic LHON tended to retain the sensitivity detectable with the size V stimulus at the central inferior nasal visual field regions, where the fixation ellipse fell. Visual acuity, which influences daily activity, was spatially correlated with residual visual sensitivity.

GABA and Glutamate in hMT+ Link to Individual Differences in Residual Visual Function After Occipital Stroke.

Damage to the primary visual cortex following an occipital stroke causes loss of conscious vision in the contralateral hemifield. Yet, some patients retain the ability to detect moving visual stimuli within their blind field. The present study asked whether such individual differences in blind field perception following loss of primary visual cortex could be explained by the concentration of neurotransmitters γ-aminobutyric acid (GABA) and glutamate or activity of the visual motion processing, human middle temporal complex (hMT+). We used magnetic resonance imaging in 19 patients with chronic occipital stroke to measure the concentration of neurotransmitters GABA and glutamate (proton magnetic resonance spectroscopy) and functional activity in hMT+ (functional magnetic resonance imaging). We also tested each participant on a 2-interval forced choice detection task using high-contrast, moving Gabor patches. We then measured and assessed the strength of relationships between participants' residual vision in their blind field and in vivo neurotransmitter concentrations, as well as visually evoked functional magnetic resonance imaging activity in their hMT+. Levels of GABA and glutamate were also measured in a sensorimotor region, which served as a control. Magnetic resonance spectroscopy-derived GABA and glutamate concentrations in hMT+ (but not sensorimotor cortex) strongly predicted blind-field visual detection abilities. Performance was inversely related to levels of both inhibitory and excitatory neurotransmitters in hMT+ but, surprisingly, did not correlate with visually evoked blood oxygenation level-dependent signal change in this motion-sensitive region. Levels of GABA and glutamate in hMT+ appear to provide superior information about motion detection capabilities inside perimetrically defined blind fields compared to blood oxygenation level-dependent signal changes-in essence, serving as biomarkers for the quality of residual visual processing in the blind-field. Whether they also reflect a potential for successful rehabilitation of visual function remains to be determined.

Estimation of Visual Function Using Deep Learning From Ultra-Widefield Fundus Images of Eyes With Retinitis Pigmentosa

There is no widespread effective treatment to halt the progression of retinitis pigmentosa. Consequently, adequate assessment and estimation of residual visual function are important clinically. To examine whether deep learning can accurately estimate the visual function of patients with retinitis pigmentosa by using ultra-widefield fundus images obtained on concurrent visits. Data for this multicenter, retrospective, cross-sectional study were collected between January 1, 2012, and December 31, 2018. This study included 695 consecutive patients with retinitis pigmentosa who were examined at 5 institutions. Each of the 3 types of input images-ultra-widefield pseudocolor images, ultra-widefield fundus autofluorescence images, and both ultra-widefield pseudocolor and fundus autofluorescence images-was paired with 1 of the 31 types of ensemble models constructed from 5 deep learning models (Visual Geometry Group-16, Residual Network-50, InceptionV3, DenseNet121, and EfficientNetB0). We used 848, 212, and 214 images for the training, validation, and testing data, respectively. All data from 1 institution were used for the independent testing data. Data analysis was performed from June 7, 2021, to December 5, 2022. The mean deviation on the Humphrey field analyzer, central retinal sensitivity, and best-corrected visual acuity were estimated. The image type-ensemble model combination that yielded the smallest mean absolute error was defined as the model with the best estimation accuracy. After removal of the bias of including both eyes with the generalized linear mixed model, correlations between the actual values of the testing data and the estimated values by the best accuracy model were examined by calculating standardized regression coefficients and P values. The study included 1274 eyes of 695 patients. A total of 385 patients were female (55.4%), and the mean (SD) age was 53.9 (17.2) years. Among the 3 types of images, the model using ultra-widefield fundus autofluorescence images alone provided the best estimation accuracy for mean deviation, central sensitivity, and visual acuity. Standardized regression coefficients were 0.684 (95% CI, 0.567-0.802) for the mean deviation estimation, 0.697 (95% CI, 0.590-0.804) for the central sensitivity estimation, and 0.309 (95% CI, 0.187-0.430) for the visual acuity estimation (all P < .001). Results of this study suggest that the visual function estimation in patients with retinitis pigmentosa from ultra-widefield fundus autofluorescence images using deep learning might help assess disease progression objectively. Findings also suggest that deep learning models might monitor the progression of retinitis pigmentosa efficiently during follow-up.

Relating residual visual function to visual areas affected by visual field loss

Relating residual visual function to visual areas affected by visual field loss

Клинический случай хирургического лечения офтальмологических осложнений придаточного аппарата у пациента с язвой роговицы

Corneal ulcer is destructive and inflammatory changes in the cornea of the eye, with damage to the epithelium and melting of the deeper layers, accompanied by the formation of an ulcer. The lack of effect of drug treatment may be accompanied by a complication – corneal perforation, which is an absolute indication for surgical treatment: autoconjunctival corneal plasty, various types of keratoplasty. A clinical case of ophthalmic complications of the adnexa of the eye in patients with corneal ulcer, observed in the Tambov branch of the «Eye Microsurgery» complex is presented. The patient underwent therapeutic lamellar keratoplasty with autoplasty of the cornea with a conjunctival flap and temporary blepharoplasty. In the postoperative period a violation of the position of the lower eyelid (eversion), nonclosure of the palpebral fissure was revealed. The causes of this pathology were: involutional lysis of the retractor, its detachment during autoplasty of the cornea with a conjunctival flap, inflammation and scarring of the conjunctiva, and the formation of symblepharon. The patient was diagnosed with a complete ectropion of the tarsal plate – «tarsal ectropion», symblepharon and lagophthalmos. Combined surgical treatment was performed: dissection of symblepharon with plastic surgery of the conjunctival cavity, fornix and transplantation of a free mucosal flap from the lip; elimination of ectropion (refixation of the lower eyelid retractor with fixation to the tarso-orbital fascia) and blepharorrhaphy. The presence of complex ectropions of degree IV requires a combination of different techniques, and the need for conjunctival transplantation also arises. Surgical treatment of symblepharon with plasty with a free mucosal flap from the lip makes it possible to restore the anatomy of the eyelid, conjunctival cavity and fornix. Entropion of the lower eyelid can be eliminated by creating a duplication, refixation of the retractor to the inferoposterior edge of the cartilage and fixation to the tarsoorbital fascia. A positive result has been achieved as a result of combined treatment, which consists in restoring the protective function of the eyelids, maintaining residual visual functions, and eliminating the risk of losing the eye as an organ. It was also possible to improve the quality of life of the patient, relieving him of lacrimation, corneal dryness. Keywords: corneal ulcer, keratitis, ectropion, lagophthalmos

Spared perilesional V1 activity underlies training-induced recovery of luminance detection sensitivity in cortically-blind patients

Damage to the primary visual cortex (V1) causes homonymous visual-field loss long considered intractable. Multiple studies now show that perceptual training can restore visual functions in chronic cortically-induced blindness (CB). A popular hypothesis is that training can harness residual visual functions by recruiting intact extrageniculostriate pathways. Training may also induce plastic changes within spared regions of the damaged V1. Here, we link changes in luminance detection sensitivity with retinotopic fMRI activity before and after visual discrimination training in eleven patients with chronic, stroke-induced CB. We show that spared V1 activity representing perimetrically-blind locations prior to training predicts the amount of training-induced recovery of luminance detection sensitivity. Additionally, training results in an enlargement of population receptive fields in perilesional V1, which increases blind-field coverage and may support further recovery with subsequent training. These findings uncover fundamental changes in perilesional V1 cortex underlying training-induced restoration of conscious luminance detection sensitivity in CB.

Current Modalities for Low Vision Rehabilitation.

Visual rehabilitation is an effective method for increasing the quality of life among individuals with low vision or blindness due to untreatable causes. Low vision rehabilitation aims for patients to use their residual vision effectively and efficiently to enable them to live independent and productive lives. Low vision rehabilitation includes assessment of residual visual functions, prescription of rehabilitation aids, and training in the use of devices. A multidisciplinary approach and coordinated effort are necessary to take advantage of new scientific advances and achieve optimal results for the patient. This article aims to review the various aids and methods available for low vision rehabilitation and also discusses technology advances that can enhance the visual functioning of individuals who are visually impaired.

Blindsight is qualitatively degraded conscious vision.

Blindsight is a neuropsychological condition defined by residual visual function following destruction of primary visual cortex. This residual visual function is almost universally held to include capacities for voluntary discrimination in the total absence of awareness. So conceived, blindsight has had an enormous impact on the scientific study of consciousness. It is held to reveal a dramatic disconnect between performance and awareness and used to motivate diverse claims concerning the neural and cognitive basis of consciousness. Here I argue that this orthodox understanding of blindsight is fundamentally mistaken. Drawing on models from signal detection theory in conjunction with a wide range of behavioral and first-person evidence, I contend that blindsight is severely and qualitatively degraded but nonetheless conscious vision, unacknowledged due to conservative response biases. Psychophysical and functional arguments to the contrary are answered. A powerful positive case for the qualitatively degraded conscious vision hypothesis is then presented, detailing a set of distinctive predictions borne out by the data. Such data are further used to address the question of what it is like to have blindsight, as well as to explain the conservative and selectively unstable response criteria exhibited by blindsight subjects. On the view defended, blindsight does not reveal any dissociation between performance and awareness, nor does it speak to the neural or cognitive requirements for consciousness. A foundation stone of consciousness science requires radical reconsideration. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

A Common Approach and Low Vision Rehabilitation in Patients with Hereditary Retinal Diseases

The goal of low vision rehabilitation is to produce people who are independent, have an economically viable profession or skill, and are able to enjoy their lives. Patients with hereditary retinal dystrophies are candidates for low vision rehabilitation from the time of diagnosis, since their disease shows a progressive course, there is no proven precise treatment and the disease especially seriously affects the vision of individuals of school age and productive age. The stages of modern low vision rehabilitation include the intake interview, assessment of residual visual functions, assessment of residual functional vision, interventions and recommendations, and vision rehabilitation therapies.

EXPERIENCE OF LUCENTIS APPLICATION IN TREATMENT OF NEOVASCULAR GLAUCOMA AGAINST THE BACKGROUND OF PROLIFERATIVE DIABETIC RETINOPATHY

The study involved 23 patients (23 eyes) with neovascular glaucoma against the background of proliferative diabetic retinopathy. The first stage was the intravitreal injection of Lucentis, then with IOP &gt; 25 mm Hg - transscleral cyclophotocoagulation and after 2 weeks panretinal laser coagulation in ischemic zones; with IOP &lt; 25 mm Hg - panretinal laser coagulation in ischemic zones. At all observation periods there was a statistically significant decrease in IOP and in rubeosis. One week after the last stage of treatment the overall decrease in IOP was 33.4 % of the initial values, rubeosis was not detected. The application of Lucentis in combination with transscleral cyclophotocoagulation in the treatment of neovascular glaucoma against the background of proliferative diabetic retinopathy allows to achieve stable IOP normalization, preserving residual visual functions and reducing the risk of hemorrhagic complications.

Ocular Characteristics of Patients With Bardet-Biedl Syndrome Caused by Pathogenic BBS Gene Variation in a Chinese Cohort.

Bardet–Biedl syndrome (BBS; OMIM 209900) is a rare genetic disease causing damage to multiple organs and affecting patients’ quality of life in late adolescence or early adulthood. In this study, the ocular characteristics including morphology and function, were analyzed in 12 BBS patients from 10 Chinese families by molecular diagnostics. A total of five known and twelve novel variants in four BBS genes (BBS2, 58.33%; BBS4, 8.33%; BBS7, 16.67%; and BBS9, 16.67%) were identified in 10 Chinese families with BBS. All patients had typical phenotypes of retinitis pigmentosa with unrecordable or severely damaged cone and rod responses on full-field flash electroretinography (ffERG). Most of the patients showed unremarkable reactions in pattern visual evoked potential (PVEP) and multifocal electroretinography (mfERG), while their flash visual evoked potentials (FVEP) indicated display residual visual function. Changes in the fundus morphology, including color fundus photography and autofluorescence (AF) imaging, were heterogeneous and not consistent with the patients’ functional tests. Overall, our study expands the variation spectrum of the BBS gene, showing that the ocular characteristics of BBS patients are clinically highly heterogeneous, and demonstrates the usefulness of a combination of the ffERG and FVEP assessments of visual function in the advanced stage of retinopathy in BBS.

Saccadic adaptation in the presence of artificial central scotomas.

Saccadic adaptation can occur over a short period of time through a constant adjustment of the saccade target during the saccade, resulting in saccadic re-referencing, which directs the saccade to a location different from the target that elicited the saccade. Saccade re-referencing could be used to help patients with age-related macular degeneration to optimally use their residual visual function. However, it remains unknown whether saccade adaptation can take place in the presence of central scotomas (i.e., without central vision). We tested participants in two experiments in a conventional double-step paradigm with a central gaze-contingent artificial scotoma. Experiment 1 (N = 12) comprised a backward adaptation paradigm with no scotoma control, visible, and invisible 3° diameter scotoma conditions. Experiment 2 (N = 13) comprised a forward adaptation paradigm with no scotoma control, invisible 2°, and 4° diameter scotoma conditions. In Experiment 1, we observed significant adaptation in both the visible and invisible scotoma conditions comparable to the control condition with no scotoma. This was the case even when the saccade landed such that the target was occluded by the scotoma. We observed that adaptation occurred based on peripheral viewing of the stepped target during the deceleration period. In Experiment 2, we found that both scotoma conditions showed adaptation again comparable to the control condition with no scotoma. We conclude that saccadic adaptation can occur with central scotomas, showing that it does not require central vision and can be driven primarily by peripheral retinal error.

Quantitative assessment of visual pathway function in blind retinitis pigmentosa patients

ObjectiveThe current methods used to assess visual function in blind retinitis pigmentosa (RP) patients are mostly subjective. We aimed to identify effective, objective methods. MethodsWe enrolled patients diagnosed with blindness associated with RP; we finally selected 26 patients (51 eyes) with a visual field radius less than 10 degrees and divided them into the following 4 groups by best-corrected visual acuity (BCVA): group 1, no light perception (NLP, 4 eyes); group 2, light perception (LP, 12 eyes); group 3, hand movement or finger counting (faint form perception, FFP, 22 eyes); and group 4, BCVA from 0.1 to 0.8 (form perception, FP, 13 eyes). All patients underwent optometry, optical coherence tomography (OCT), color fundus photography, fundus autofluorescence (FAF), full field electroretinography (ffERG), pattern electroretinography (PERG), multifocal electroretinography (mf-ERG), pattern visual evoked potential (PVEP), flash visual evoked potential (FVEP), and pupillary light response (PLR) assessments. Five patients in groups 1, 2, and 3 (1, 2, and 2 subjects, respectively) underwent functional magnetic resonance imaging (fMRI) scans and were compared with five healthy subjects. ResultsThe outer plexiform layer was thinner in group 1, and the outer nuclear layer was thinner in groups 1 and 2. The ffERG, PERG, and mf-ERG findings were unrecordable in all four groups. The P2 amplitude of the FVEP was significantly lower in groups 1 and 2, while the P100 amplitude of the PVEP was higher in groups 2, 3 and 4 than in group 1. After white- and blue-light stimuli, the PLR thresholds in the patients without form perception were significantly higher. The threshold of the PLR stimulated by blue and white light was negatively correlated with the amplitudes of P2 and P100. Moreover, the fMRI findings showed that some RP patients have significant visual cortex activation in response to certain types of stimulation. However, statistical analysis was not performed because of the small number of cases. ConclusionsOCT, VEP, PLR and fMRI assessments can evaluate residual visual pathway function in blind RP patients. SignificanceOur study may have clinical significance for the potential prediction of RP patient prognoses and the effects after clinical trials.

Assessing Residual Cone Function in Retinitis Pigmentosa Patients.

PurposeThe purpose of this study was to investigate cone function deterioration in patients with retinitis pigmentosa (RP) using full field electroretinogram (ffERG), pattern electroretinogram (pERG), and optical coherence tomography (OCT) and their correlation with visual acuity (VA).MethodsClinical records (2008–2018) of patients with RP undergoing repeat electrophysiology were reviewed. Results of ffERG (30 Hz flicker and fused flicker amplitude [FFAmp]), pERG [p50 and n95], and macular OCT (ellipsoid zone [EZ] and outer segment thickness) were collected.ResultsOne hundred twenty-six eyes from 63 patients (33 women, mean age 35 years) were included. The mean decline in VA was 0.11 ± 0.14 logarithm of minimum angle of resolution (logMAR). The FFAmp decreased by 3.01 ± 5.9 µV with global cone function deteriorating by 18.7% annually. The percentage change in FFAmp (RE [r = 0.553], LE [r = 0.531]), and 30 Hz flicker amplitude (RE [r = 0.615], LE [r = 0.529]) strongly correlated with VA (P < 0.00001). The pERG p50 (15 and 30 degrees) change analyzed in 34 patients showed reduction by 23% and 23.4%, respectively. The percentage change in p50 30 degrees (r = 0.397) correlated with VA and EZ layer (P < 0.05). The EZ layer change was calculated in 45 patients and the shortening and thinning rate was 4.3% and 4.4% annually, respectively. The EZ length percentage change correlated with VA (RE [r = 0.34] and LE [r = 0.466; P < 0.05).ConclusionsWe quantified the decline in cone function in patients with RP utilizing ffERG and FFAmp measures of residual cone function. These parameters correlated with VA and OCT when measurable. These objective measures may assist in monitoring disease progression.Translational RelevanceResidual cone function provides an objective estimate of residual visual function, which aids in counselling patients regarding prognosis.

Management of Full-Thickness Macular Hole in A Genetically Confirmed Case with Usher Syndrome.

IntroductionFull-thickness macular hole (FTMH) formation is rarely seen in patients with retinitis pigmentosa (RP) and can have an adverse impact on their residual visual function. The underlying mechanisms are unknown, and clinical experience is limited regarding surgical outcomes. Here, we describe the surgical management of FTMH in a young patient with genetically confirmed Usher syndrome, the most common form of syndromic RP.Case ReportA 28-year-old woman presented with blurred vision in her right eye (RE). She had a history of RP and bilateral hearing impairment since childhood. Fundoscopy and spectral-domain optical coherence tomography revealed a FTMH in the RE along with typical RP features bilaterally. After pars plana vitrectomy (PPV) with internal limiting membrane peel and gas tamponade, the FTMH closed. Six months after PPV the patient underwent cataract surgery in the affected eye, and the visual acuity remained stable compared to baseline. The clinical diagnosis of Usher syndrome was genetically confirmed by whole exome sequencing (WES), which revealed the presence of two pathogenic nucleotide variants in trans (compound heterozygosity) in the gene USH2A.ConclusionWe report a rare case of successful closure of a FTMH in a patient with Usher syndrome. Surgical treatment of FTMH can help preserve the central vision in RP patients, whose peripheral vision is severely affected.

Biofeedback Rehabilitation and Visual Cortex Response in Stargardt's Disease: A Randomized Controlled Trial.

Purposeto evaluate the effect of biofeedback (BF) rehabilitation on the visual function and on the activity of primary visual cortex (PVC) in patients with Stargardt's disease owing to mutations in the ABCA4 gene (STGD1).MethodsThis was a single-center, controlled, randomized study. Twenty-four patients with STGD1 were randomized into two groups: a treatment group (TG) undergoing BF rehabilitation and a control group (CG). Treatment with BF consisted of a 10-minute session per eye performed weekly for 12 weeks. The subjects underwent a baseline and 3-month follow-up visits, including best-corrected visual acuity (BCVA), reading test, microperimetry, and functional magnetic resonance imaging (fMRI). The fMRI studies were acquired sequentially using a passive viewing condition and an active reading task. The primary outcomes were the change in the fMRI activation of primary visual cortex and the change in reading ability.ResultsAfter treatment, the patients in the TG were able to read smaller characters (P = 0.002) with a greater reading speed (P = 0.014) compared with patients in the CG. The fMRI studies showed a significant effect (P < 0.001) of BF on primary visual cortex activation in the TG compared with the CG. Finally, we observed significant (P < 0.05) improvements of best-corrected visual acuity, macular sensitivity, and fixation stability parameters in the TG compared with the CG.ConclusionsOur study showed that visual rehabilitation using BF improved the usage of residual visual function in patients with STGD1.Translational RelevanceOur findings show that the BF treatment compared with no treatment at all resulted in benefits. The specificity of the treatment could be examined to determine whether BF can be included in clinical practice.