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Journal of Surgical Case Reports May 2024We herein report a case of a 4-year-old female patient who presented with anisometropic amblyopia with initial visual acuity recorded at 20/400 OD and 20/100 OS. The...
We herein report a case of a 4-year-old female patient who presented with anisometropic amblyopia with initial visual acuity recorded at 20/400 OD and 20/100 OS. The patient was recommended for patching. Eighteen months later, the patient presented with visual acuity of 20/60 OD and 20/80 and reverse amblyopia was noted. In settings of amblyopia, where alternate patching may be used, it is most likely that reverse amblyopia, if present, will affect the more myopic eye. However, unexpectedly, in this case, reverse amblyopia occurred in the less myopic eye. With discontinuation of occlusion therapy and continued use of optical correction, the patients reverse amblyopia resolved and the visual equity equalized. To our knowledge, this is the first case described in the literature demonstrating such an occurrence. Awareness of this rare presentation by clinicians is of great importance to aid in correctly diagnosing and treating such patients.
PubMed: 38784199
DOI: 10.1093/jscr/rjae320 -
Translational Vision Science &... May 2024This study aimed to investigate the possible relationship between retinal vascular abnormalities and amblyopia by analyzing vascular structures of fundus images. (Observational Study)
Observational Study
PURPOSE
This study aimed to investigate the possible relationship between retinal vascular abnormalities and amblyopia by analyzing vascular structures of fundus images.
METHODS
In this observational study, retinal fundus images were collected from 36 patients with unilateral amblyopia, 33 patients with bilateral amblyopia, and 36 healthy control volunteers. We developed a customized training algorithm based on U-Net to digitalize the vasculature in the fundus images to quantify vascular density (area and fractal dimension), skeleton length, and number of bifurcation points. For statistical comparisons, this study divided participants into two groups. The amblyopic eyes and the fellow eyes of patients with unilateral amblyopia formed the paired group, while bilateral amblyopic patients and healthy controls formed the independent group.
RESULTS
In the paired group, the vascular area (P = 0.007), vascular fractal dimension (P = 0.007), and vascular skeleton length (P = 0.002) of the amblyopic eyes were significantly smaller than those of the fellow eyes. In the independent group, significant decreases in the vascular fractal dimension (P = 0.006) and skeleton length (P = 0.048) were observed in bilateral amblyopia compared to control. The vascular area was also significantly correlated with best-corrected visual acuity in amblyopic eyes.
CONCLUSIONS
This study demonstrated that retinal vascular density and skeleton length in amblyopic eyes were significantly smaller compared to control, indicating an association between the changes in retinal vascular features and the state of amblyopia.
TRANSLATIONAL RELEVANCE
Our algorithm presents amblyopic retinal vascular changes that are more biologically interpretable for both clinicians and researchers.
Topics: Humans; Amblyopia; Female; Male; Retinal Vessels; Visual Acuity; Algorithms; Adult; Young Adult; Adolescent; Child; Fractals; Microvascular Density
PubMed: 38780954
DOI: 10.1167/tvst.13.5.21 -
Eye (London, England) May 2024Functional visual loss is a subtype of functional neurological disorder (FND) and is a common cause of visual impairment seen in both general and neuro-ophthalmological... (Review)
Review
Functional visual loss is a subtype of functional neurological disorder (FND) and is a common cause of visual impairment seen in both general and neuro-ophthalmological practice. Ophthalmologists can generally diagnose functional visual loss reasonably confidently but often find it harder to know what to say to the patient, how to approach, or even whether to attempt, treatment. There is little evidence-based treatment despite studies showing up to 60% of adults having impactful symptoms on long-term follow-up. The last 20 years has seen large changes in how we understand, approach, and manage FND more widely. In this article, we set out our practical approach to managing functional visual loss which includes : 1) Make a positive diagnosis based on investigations that demonstrate normal vision in the presence of subjectively impaired vision, not just because tests or ocular exam is normal; 2) Explain and label the condition with an emphasis on these positive diagnostic features, not reassurance; 3) Consider eye or brain comorbidities such as migraine, idiopathic intracranial hypertension or amblyopia; 4) Consider working with an orthoptist using diagnostic tests in a positive way to highlight the possibility of better vision; 5) Develop simple treatment strategies for photophobia; 6) Consider psychological factors and comorbidity as part of assessment and therapy, but keep a broader view of aetiology and don't use this to make a diagnosis; 7) Other treatment modalities including hypnotherapy, transcranial magnetic stimulation and more advanced forms of visual feedback are promising candidates for functional visual loss treatment in the future.
PubMed: 38778139
DOI: 10.1038/s41433-024-03126-w -
Translational Vision Science &... May 2024We aimed to design, develop, and evaluate an internet of things-enabled patch (IoT patch) for real-time remote monitoring of adherence (or patch wear time) during patch...
PURPOSE
We aimed to design, develop, and evaluate an internet of things-enabled patch (IoT patch) for real-time remote monitoring of adherence (or patch wear time) during patch treatment in child participants in clinical trials. This study provides healthcare providers with a tool for objective, real-time, and remote assessment of adherence and for making required adjustments to treatment plans.
METHODS
The IoT patch had two temperature microsensors and a wireless chip. One sensor was placed closer to the skin than the other, resulting in a temperature difference depending on whether the patch was worn. When the patch was worn, it measured temperatures every 30 seconds and transmitted temperature data to a cloud server via a mobile application every 15 seconds. The patch was evaluated via 2 experiments with 30 healthy adults and 40 children with amblyopia.
RESULTS
Excellent monitoring accuracy was observed in both adults (mean delay of recorded time data, 0.4 minutes) and children (mean, 0.5 minutes). The difference between manually recorded and objectively recorded patch wear times showed good agreement in both groups. Experiment 1 showed accurate monitoring over a wide range of temperatures (from 0 to 30°C). Experiment 2 showed no significant differences in wearability (ease-of-use and comfort scores) between the IoT and conventional patches.
CONCLUSIONS
The IoT patch offers an accurate, real-time, and remote system to monitor adherence to patch treatment. The patch is comfortable and easy to use. The utilization of an IoT patch may increase adherence to patch treatment based on accurate monitoring.
TRANSLATIONAL RELEVANCE
Results show that the IoT patch can enable real-time adherence monitoring in clinical trials, improving treatment precision, and patient compliance to enhance outcomes.
Topics: Humans; Female; Male; Adult; Child; Wireless Technology; Internet of Things; Patient Compliance; Equipment Design; Child, Preschool; Young Adult; Wearable Electronic Devices; Remote Sensing Technology
PubMed: 38776108
DOI: 10.1167/tvst.13.5.18 -
Journal of Neurophysiology Jul 2024When adult mice are repeatedly exposed to a particular visual stimulus for as little as 1 h per day for several days while their visual cortex (V1) is in the high-gain...
When adult mice are repeatedly exposed to a particular visual stimulus for as little as 1 h per day for several days while their visual cortex (V1) is in the high-gain state produced by locomotion, that specific stimulus elicits much stronger responses in V1 neurons for the following several weeks, even when measured in anesthetized animals. Such stimulus-specific enhancement (SSE) is not seen if locomotion is prevented. The effect of locomotion on cortical responses is mediated by vasoactive intestinal peptide (VIP) positive interneurons, which can release both the peptide and the inhibitory neurotransmitter GABA. Previous studies have examined the role of VIP-ergic interneurons, but none have distinguished the individual roles of peptide from GABA release. Here, we used genetic ablation to determine which of those molecules secreted by VIP-ergic neurons is responsible for SSE. SSE was not impaired by VIP deletion but was prevented by compromising release of GABA from VIP cells. This finding suggests that SSE may result from Hebbian mechanisms that remain present in adult V1. Many neurons package and release a peptide along with a conventional neurotransmitter. The conventional view is that such peptides exert late, slow effects on plasticity. We studied a form of cortical plasticity that depends on the activity of neurons that express both vasoactive intestinal peptide (VIP) and the inhibitory neurotransmitter GABA. GABA release accounted for their action on plasticity, with no effect of deleting the peptide on this phenomenon.
Topics: Animals; Vasoactive Intestinal Peptide; Interneurons; gamma-Aminobutyric Acid; Mice; Visual Cortex; Mice, Inbred C57BL; Male; Photic Stimulation; Female
PubMed: 38774975
DOI: 10.1152/jn.00463.2023 -
Clinical & Experimental Optometry May 2024Non-invasive brain stimulation techniques allow targeted modulation of brain regions and have emerged as a promising tool for vision rehabilitation. This review presents... (Review)
Review
Non-invasive brain stimulation techniques allow targeted modulation of brain regions and have emerged as a promising tool for vision rehabilitation. This review presents an overview of studies that have examined the use of non-invasive brain stimulation techniques for improving vision and visual functions. A description of the proposed neural mechanisms that underpin non-invasive brain stimulation effects is also provided. The clinical implications of non-invasive brain stimulation in vision rehabilitation are examined, including their safety, effectiveness, and potential applications in specific conditions such as amblyopia, post-stroke hemianopia, and central vision loss associated with age-related macular degeneration. Additionally, the future directions of research in this field are considered, including the need for larger and more rigorous clinical trials to validate the efficacy of these techniques. Overall, this review highlights the potential for brain stimulation techniques as a promising avenue for improving visual function in individuals with impaired vision and underscores the importance of continued research in this field.
PubMed: 38772676
DOI: 10.1080/08164622.2024.2349565 -
Current Biology : CB Jun 2024ON and OFF thalamic afferents from the two eyes converge in the primary visual cortex to form binocular receptive fields. The receptive fields need to be diverse to...
ON and OFF thalamic afferents from the two eyes converge in the primary visual cortex to form binocular receptive fields. The receptive fields need to be diverse to sample our visual world but also similar across eyes to achieve binocular fusion. It is currently unknown how the cortex balances these competing needs between receptive-field diversity and similarity. Our results demonstrate that receptive fields in the cat visual cortex are binocularly matched with exquisite precision for retinotopy, orientation/direction preference, orientation/direction selectivity, response latency, and ON-OFF polarity/structure. Specifically, the average binocular mismatches in retinotopy and ON-OFF structure are tightly restricted to 1/20 and 1/5 of the average receptive-field size but are still large enough to generate all types of binocular disparity tuning. Based on these results, we conclude that cortical receptive fields are binocularly matched with the high precision needed to facilitate binocular fusion while allowing restricted mismatches to process visual depth.
Topics: Animals; Cats; Vision, Binocular; Primary Visual Cortex; Visual Fields; Visual Cortex; Vision Disparity
PubMed: 38772362
DOI: 10.1016/j.cub.2024.04.058 -
Investigative Ophthalmology & Visual... May 2024Although effective amblyopia treatments are available, treatment outcome is unpredictable, and the condition recurs in up to 25% of the patients. We aimed to evaluate...
PURPOSE
Although effective amblyopia treatments are available, treatment outcome is unpredictable, and the condition recurs in up to 25% of the patients. We aimed to evaluate whether a large-scale quantitative contrast sensitivity function (CSF) data source, coupled with machine learning (ML) algorithms, can predict amblyopia treatment response and recurrence in individuals.
METHODS
Visual function measures from traditional chart vision acuity (VA) and novel CSF assessments were used as the main predictive variables in the models. Information from 58 potential predictors was extracted to predict treatment response and recurrence. Six ML methods were applied to construct models. The SHapley Additive exPlanations was used to explain the predictions.
RESULTS
A total of 2559 consecutive records of 643 patients with amblyopia were eligible for modeling. Combining variables from VA and CSF assessments gave the highest accuracy for treatment response prediction, with the area under the receiver operating characteristic curve (AUC) of 0.863 and 0.815 for outcome predictions after 3 and 6 months, respectively. Variables from the VA assessment alone predicted the treatment response, with AUC values of 0.723 and 0.675 after 3 and 6 months, respectively. Variables from the CSF assessment gave rise to an AUC of 0.909 for recurrence prediction compared to 0.539 for VA assessment alone, and adding VA variables did not improve predictive performance. The interocular differences in CSF features are significant contributors to recurrence risk.
CONCLUSIONS
Our models showed CSF data could enhance treatment response prediction and accurately predict amblyopia recurrence, which has the potential to guide amblyopia management by enabling patient-tailored decision making.
Topics: Humans; Amblyopia; Visual Acuity; Male; Female; Recurrence; Contrast Sensitivity; Child; Treatment Outcome; Child, Preschool; ROC Curve; Machine Learning; Retrospective Studies; Adolescent; Sensory Deprivation; Algorithms
PubMed: 38771572
DOI: 10.1167/iovs.65.5.31 -
JAMA Ophthalmology May 2024
Topics: Humans; Hamartoma; Retinal Pigment Epithelium; Retinal Diseases; Hyperplasia; Tomography, Optical Coherence; Fluorescein Angiography; Female; Male
PubMed: 38770959
DOI: 10.1001/jamaophthalmol.2023.4938 -
Cureus Apr 2024Persistent fetal vasculature (PFV) is a rare ocular developmental disorder resulting from incomplete apoptosis of the embryonic hyaloid vasculature during the in-utero...
Persistent fetal vasculature (PFV) is a rare ocular developmental disorder resulting from incomplete apoptosis of the embryonic hyaloid vasculature during the in-utero period. Variability in the development and regression of hyaloid vasculature is responsible for the wide range of clinical presentation of the disorder. PFV may manifest as anterior segment abnormalities (cataract, glaucoma, microphthalmia, elongated ciliary process with central traction, retrolental membrane, and shallow anterior chamber), posterior segment abnormalities (vitreous stalk, preretinal membranes, optic hypoplasia, and retinal folds), or with a combined anteroposterior disease. The most common associated clinical feature is leukocoria with microphthalmia and usually unilateral presentation. Most of the cases have poor visual prognosis and present early in childhood. Association with myopia is a very rare and atypical presentation, especially unilateral cases which may present later in life and have a good visual prognosis. Hereby, we present a case of a 27-year-old young adult male with unilateral atypical myopic posterior PFV with anisometropic amblyopia and good functional vision in the right eye.
PubMed: 38770505
DOI: 10.7759/cureus.58623