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Survey of Ophthalmology May 2024Amblyopia is a form of visual cortical impairment that arises from abnormal visual experience early in life. Most often, amblyopia is a unilateral visual impairment that... (Review)
Review
Amblyopia is a form of visual cortical impairment that arises from abnormal visual experience early in life. Most often, amblyopia is a unilateral visual impairment that can develop as a result of strabismus, anisometropia, or a combination of these conditions that result in discordant binocular experience. Characterized by reduced visual acuity and impaired binocular function, amblyopia places a substantial burden on the developing child. Although frontline treatment with glasses and patching can improve visual acuity, residual amblyopia remains for most children. Newer binocular-based therapies can elicit rapid recovery of visual acuity and may also improve stereoacuity in some children. Nevertheless, for both treatment modalities full recovery is elusive, recurrence of amblyopia is common, and improvements are negligible when treatment is administered at older ages. Insights derived from animal models about the factors that govern neural plasticity have been leveraged to develop innovative treatments for amblyopia. These novel therapies exhibit efficacy to promote recovery, and some are effective even at ages when conventional treatments fail to yield benefit. Approaches for enhancing visual system plasticity and promoting recovery from amblyopia include altering the balance between excitatory and inhibitory mechanisms, reversing the accumulation of proteins that inhibit plasticity, and harnessing the principles of metaplasticity. Although these therapies have exhibited promising results in animal models, their safety and ability to remediate amblyopia need to be evaluated in humans.
PubMed: 38763223
DOI: 10.1016/j.survophthal.2024.04.006 -
Frontiers in Neuroscience 2024Cell signaling based on homeoprotein transfer is a pathway with developmental and physiological functions. For a few transcription factors of this family, primarily... (Review)
Review
Cell signaling based on homeoprotein transfer is a pathway with developmental and physiological functions. For a few transcription factors of this family, primarily ENGRAILED1, ENGRAILED2 and OTX2, their physiological functions have led to therapeutic strategies in animal models of human diseases, including Parkinson's disease, amyotrophic lateral sclerosis, amblyopia and anxiety-related disorders. In mesencephalic dopaminergic neurons which degenerate in Parkinson's disease, ENGRAILED1/2 have cell autonomous activities, but their transducing properties enables their use as therapeutic proteins. In contrast, in spinal alpha-motoneurons, which are lost in amyotrophic lateral sclerosis, ENGRAILED1 is supplied by V1 interneurons. Thus, its use as a therapeutic protein to protect alpha-motoneurons against degeneration mimics its normal non-cell autonomous neurotrophic activity. OTX2, synthesized and secreted by the choroid plexus, is transferred to parvalbumin interneurons and exerts regulatory functions controlling cerebral cortex plasticity. Understanding the latter OTX2 function has led to strategies for manipulating visual acuity and anxiety-like behavior in adult mice. In this review, we describe these cases and what is known about the involved molecular mechanisms. Because the transduction sequences are conserved in most of the few hundred homeoproteins, we argue how this family of molecules constitutes an important reservoir of physiological knowledge, with potential consequences in the search for new therapeutic strategies.
PubMed: 38550565
DOI: 10.3389/fnins.2024.1359523 -
Taiwan Journal of Ophthalmology 2023Axenfeld-Rieger syndrome (ARS) is a rare autosomal-dominant neurocristopathy that presents with a variety of classical ocular and systemic findings. The pathophysiology... (Review)
Review
Axenfeld-Rieger syndrome (ARS) is a rare autosomal-dominant neurocristopathy that presents with a variety of classical ocular and systemic findings. The pathophysiology of the disease involves anterior segment dysgenesis, and patients may present with ophthalmic complications early in life, including secondary glaucoma, high refractive errors, amblyopia, and permanent visual damage. There are a limited number of studies in the literature that focus primarily on pediatric patients with ARS. The purpose of this article was to review the current literature on clinical presentation, genetic associations, diagnosis, secondary complications, and treatment of ARS in pediatric patients. Evaluating the essential clinical aspects of the disease in children may allow for earlier diagnosis and treatment and prevent visual morbidity from amblyopia and secondary glaucoma that may result in permanent visual damage.
PubMed: 38249500
DOI: 10.4103/tjo.TJO-D-23-00089 -
Journal of Clinical Medicine Sep 2023Childhood glaucoma is one of the most common causes of corneal opacity in childhood and is associated with various pathological corneal changes, including corneal...
BACKGROUND
Childhood glaucoma is one of the most common causes of corneal opacity in childhood and is associated with various pathological corneal changes, including corneal enlargement, corneal clouding, and edema. Congenital glaucoma (CG) may cause a decrease in vision outcomes due to corneal opacity or clouding, which is often associated with stimulus deprivation amblyopia. Therefore, to create a balance between preventing amblyopia and sustaining corneal clearance, patients with CG can be managed with early penetrating corneal transplantation surgery along with advanced glaucoma management.
AIM
To investigate the graft survival rate and factors affecting graft survival in patients with congenital glaucoma who underwent penetrating keratoplasty (PKP).
STUDY DESIGN
Cross-sectional.
MATERIALS AND METHODS
Patients with congenital glaucoma who underwent PKP were retrospectively evaluated. The associations between age, corneal diameter, presence of ocular comorbidities, concurrent ocular surgeries with corneal graft, and visual outcomes were assessed.
RESULTS
Among the 30 eyes enrolled in the study, 6 (20%) had aniridia, 6 (20%) had Axenfeld-Rieger syndrome, and 18 (60%) were diagnosed with primary congenital glaucoma. Graft survival rates were 66.6% and 63.33% at 12 and 24 months, respectively. At the end of the follow-up, the overall graft survival rate was 60%. Statistical significance was observed between patient age at the time of surgery and graft failure ( = 0.02). Graft failure was associated with a younger patient age. Functional vision was achieved in 53.3% of patients.
CONCLUSIONS
The management of congenital glaucoma and its corneal complications is a delicate issue that requires great effort. PKP in congenital glaucoma was moderately successful in the present study. To provide functional vision, PKP could be the treatment of choice.
PubMed: 37834920
DOI: 10.3390/jcm12196276 -
Clinical Case Reports Sep 2023One of the clinical presentations of traumatic cataracts is a rosette-shaped posterior capsular opacity. The severity of vision loss, the patient's age, and the cornea,...
One of the clinical presentations of traumatic cataracts is a rosette-shaped posterior capsular opacity. The severity of vision loss, the patient's age, and the cornea, macula, and optic nerve states are major determinants of the therapeutic approach.
PubMed: 37636876
DOI: 10.1002/ccr3.7834 -
European Journal of Ophthalmology Jul 2023Amblyopia is the decreased best-corrected visual acuity (BCVA) in one or both eyes caused by the abnormal processing of visual input during development. One common cause... (Review)
Review
Amblyopia is the decreased best-corrected visual acuity (BCVA) in one or both eyes caused by the abnormal processing of visual input during development. One common cause of amblyopia is anisometropia, which has attracted widespread attention. Many structural changes occur in the primary and extrastriate visual areas of the cerebral cortex, as well as in the eyes, in patients with anisometropic amblyopia. Understanding these mechanisms has provided a favorable theoretical basis for treating anisometropic amblyopia. This article reviews the functional and anatomical changes and progress toward the treatment of anisometropic amblyopia.
Topics: Humans; Amblyopia; Visual Acuity; Eye; Anisometropia
PubMed: 36448184
DOI: 10.1177/11206721221143164 -
Ophthalmology and Therapy Oct 2023Amblyopia is a reduction in vision in one or both eyes due to impaired development of the visual pathway. This study explored the experience of amblyopia and treatment...
INTRODUCTION
Amblyopia is a reduction in vision in one or both eyes due to impaired development of the visual pathway. This study explored the experience of amblyopia and treatment from the patient, caregiver, and clinician perspectives.
METHODS
A targeted literature review, including a review of social media listening (SML) studies, was conducted. Next, qualitative interviews were conducted with amblyopia patients, caregivers of children with amblyopia, and ophthalmologists with experience treating patients with amblyopia. The findings informed the development of a disease model. Amblyopia clinical experts provided input at key stages.
RESULTS
Twelve data sources were reviewed, including qualitative studies in the literature and SML studies. Overall, 133 patients/caregivers were interviewed (23 adults, 16 adolescents, 47 child-caregiver dyads), plus 10 ophthalmologists from the United States, France, and Germany. Reduced visual acuity, impaired depth perception, impaired peripheral vision, and double vision were the most frequently reported symptoms. Amblyopia impacted daily activities (reading, using digital devices), the ability to move around, school/work (productivity, seeing the board in class), emotional well-being (frustration, sadness), and social functioning (difficulty socializing). Treatments, including patching and corrective lens, also impacted daily activities (using digital devices, sports/leisure), mobility (bumping into things), and work/school (tasks taking longer) as well as emotional well-being (embarrassment), and social functioning (bullying/stigma).
CONCLUSION
The findings contribute valuable insights into the adult and pediatric experience of amblyopia from a multi-stakeholder perspective. The findings were used to critically assess existing clinical outcome assessments and supported the development of patient- and observer-reported outcome measures for use in amblyopia clinical trials.
PubMed: 37356087
DOI: 10.1007/s40123-023-00751-8 -
IScience Jun 2024The association between visual abnormalities and impairments in cerebral blood flow and brain region potentially results in neural dysfunction of amblyopia....
The association between visual abnormalities and impairments in cerebral blood flow and brain region potentially results in neural dysfunction of amblyopia. Nevertheless, the differences in the complex mechanisms of brain neural network coupling and its relationship with neurotransmitters remain unclear. Here, the neurovascular coupling mechanism and neurotransmitter activity in children with anisometropic amblyopia (AA) and visual deprivation amblyopia (VDA) was explored. The neurovascular coupling of 17 brain regions in amblyopia children was significantly abnormal than in normal controls. The classification abilities of coupling units in brain regions differed between two types of amblyopia. Correlations between different coupling effects and neurotransmitters were different. The findings of this study demonstrate a correlation between the neurovascular coupling and neurotransmitter in children with AA and VDA, implying their impaired neurovascular coupling function and potential molecular underpinnings. The neuroimaging evidence revealed herein offers potential for the development of neural therapies for amblyopia.
PubMed: 38883835
DOI: 10.1016/j.isci.2024.109988