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Experimental Eye Research Nov 2023To investigate the impact of p38 mitogen-activated protein kinase (MAPK) signaling on reactivating visual cortical plasticity in adult amblyopic mice.
OBJECTIVE
To investigate the impact of p38 mitogen-activated protein kinase (MAPK) signaling on reactivating visual cortical plasticity in adult amblyopic mice.
MATERIALS AND METHODS
Reverse suture (RS), environment enrichment (EE), and combined with left intracerebroventricular injection of p38 MAPK inhibitor (SB203580, SB) or p38 MAPK agonist (dehydrocorydaline hydrochloride, DHC) were utilized to treat adult amblyopic mice with monocular deprivation (MD). The visual water task, visual cliff test, and Flash visual-evoked potential were used to measure the visual function. Then, Golgi staining and transmission electron microscopy were used to assess the reactivation of structural plasticity in adult amblyopic mice. Western blot and immunohistochemistry detected the expression of ATF2, PSD-95, p38 MAPK, and phospho-p38 MAPK in the left visual cortex.
RESULTS
No statistically significant difference was observed in the visual function in each pre-intervention group. Compared to pre-intervention, the visual acuity of deprived eyes was improved significantly, the impairment of visual depth perception was alleviated, and the P wave amplitude and C/I ratio were increased in the EE + RS, the EE + RS + SB, and the EE + RS + DMSO groups, but no significant difference was detected in the EE + RS + DHC group. Compared to EE + RS + DHC group, the density of dendritic spines was significantly higher, the synaptic density of the left visual cortex increased significantly, the length of the active synaptic zone increased, and the thickness of post-synaptic density (PSD) thickened in the left visual cortex of EE + RS, EE + RS + SB, and EE + RS + DMSO groups. And that, the protein expression of p-p38 MAPK increased while that of PSD-95 and ATF2 decreased significantly in the left visual cortex of the EE + RS + DHC group mice.
CONCLUSION
RS and EE intervention improved the visual function and synaptic plasticity of the visual cortex in adult amblyopic mice. However, activating p38 MAPK hinders the recovery of visual function by upregulating the phosphorylation of p38 MAPK and decreasing the ATF2 protein expression.
Topics: Mice; Animals; p38 Mitogen-Activated Protein Kinases; Dimethyl Sulfoxide; Visual Cortex; Amblyopia; Vision, Ocular
PubMed: 37748716
DOI: 10.1016/j.exer.2023.109651 -
The International Journal of... Jun 2024The effect of amblyopia on several sensory and perceptual functions has been widely studied. However, relatively fewer studies have evaluated the influence of amblyopia...
The effect of amblyopia on several sensory and perceptual functions has been widely studied. However, relatively fewer studies have evaluated the influence of amblyopia on visuomotor aspects. This concise but comprehensive collection of materials is to show how saccadic eye movements are severely affected by amblyopia and therefore spatiotemporal coordination between the visual and motor systems is distorted. The author hopes that recognition of these saccade deficits in amblyopia can help all eye professionals and neurologists to consider validated clinical tests related to saccadic eye movements in patients with amblyopia as these tests are not presently performed in routine clinical eye examinations.
Topics: Humans; Amblyopia; Saccades; Recognition, Psychology
PubMed: 35815630
DOI: 10.1080/00207454.2022.2100775 -
Life (Basel, Switzerland) Jul 2023(1) Background: Amblyopia is an ocular condition leading to structural and functional changes. The relationship between these changes is complex and remains poorly...
(1) Background: Amblyopia is an ocular condition leading to structural and functional changes. The relationship between these changes is complex and remains poorly understood. (2) Methods: Participants included 31 children aged 5 to 9 years with strabismic ( = 9), anisometropic ( = 16) and mixed ( = 6) unilateral amblyopia, and 14 age-matched non-amblyopic children. The 95% and 63% Bivariate Contour Ellipse Area (BCEA), axial length, Foveal Avascular Zone (FAZ) area, center macular thickness and volume were assessed. The relationship between these parameters was explored. (3) Results: Statistically significant differences were found among the four groups in best corrected distance visual acuity (BCVA) ( < 0.001), BCEA 95% ( = 0.002) and BCEA 63% ( = 0.002), but not in the FAZ area, central macular thickness, central macular volume and axial length. Eyes with amblyopia had poorer BCVA and larger fixation instability than controls. Inter-ocular differences were more significant in patients with strabismic amblyopia, particularly in BCVA ( = 0.003), central macular thickness ( < 0.001) and central macular volume ( = 0.002). In amblyopic eyes, BCEA 95% and 63% were correlated with BCVA, but not with the FAZ area. (4) Conclusion: Amblyopia is associated with a reduction in fixation stability and BCVA, although there is a general lack of correlation with structural changes, suggesting a complex interaction between anatomy and function in amblyopia.
PubMed: 37511892
DOI: 10.3390/life13071517 -
International Ophthalmology Sep 2023To evaluate fixation characteristics in amblyopia using macular analyzer integrity assessment (MAIA) microperimetry and to investigate the factors affecting fixation...
PURPOSE
To evaluate fixation characteristics in amblyopia using macular analyzer integrity assessment (MAIA) microperimetry and to investigate the factors affecting fixation stability.
METHODS
This prospective, cross-sectional study enrolled a total of 58 amblyopic patients who were between 8 and 55 years old. Average threshold macular sensitivity (AT) and fixation characteristics were assessed using MAIA microperimetry. Two Bivariate contour ellipse area (BCEA) fixation indices (63% and 95% proportional values) and the percentage of fixation points within 1° and 2° from the fovea (P1 and P2) were used to assess fixation stability. Non-amblyopic fellow eyes were used as the control group for comparison.
RESULTS
AT and fixation stability indices (P1, P2, BCEA 63%, BCEA 95%) were worse in the amblyopic eyes than in the fellow eyes (p < 0.05, for all indices). There was a moderate positive correlation between best corrected visual acuity (BCVA), and AT, and P2, and a moderate negative correlation between BCVA, and BCEA indices. 48% of the eyes were eccentrically fixating (the percentage was 25% in the anisometropic group, 52% in the strabismic group, and 69% in the combined group) and 32% in the non-amblyopic eye (p = 0.052). The preferred fixation eccentricity in amblyopic eyes was significantly greater than the non-amblyopic eyes (p = 0.004), and there was a negative correlation between preferred fixation eccentricity and BCVA (p = 0.012, r = - 0.327).
CONCLUSIONS
Our data showed a decrease in fixation stability, a positive correlation between fixation stability and BCVA, and a negative correlation between preferred fixation eccentricity and BCVA in amblyopic eyes.
Topics: Humans; Child; Adolescent; Young Adult; Adult; Middle Aged; Amblyopia; Visual Acuity; Visual Field Tests; Fixation, Ocular; Cross-Sectional Studies; Prospective Studies; Fovea Centralis
PubMed: 37184805
DOI: 10.1007/s10792-023-02748-5 -
Journal of Binocular Vision and Ocular... Oct 2023Unilateral congenital cataracts present multiple barriers in the development of vision and stereoacuity despite the improved visual optics that early surgery, contact...
Unilateral congenital cataracts present multiple barriers in the development of vision and stereoacuity despite the improved visual optics that early surgery, contact lenses and intraocular lenses (IOL) have provided. With better understanding of the latent period (the timeframe in which the abnormal event has no long-term effect on visual development in the deprived eye) and the critical periods (the age range during which developing brains can be altered in a profound and permanent way by abnormal experience) for stereoacuity and amblyopia we can focus our treatment methods to not only improve vision but also develop binocularity. Fifty years ago, it was believed that it was almost impossible for an eye with a unilateral congenital cataract to achieve good visual acuity. Twenty-five years ago, we believed that it was almost impossible for an eye with a unilateral cataract to achieve stereoacuity. It is time to expand our belief that the best that we can do with the eye in unilateral congenital cataract is to create a spare.
Topics: Humans; Child; Amblyopia; Cataract Extraction; Lens Implantation, Intraocular; Cataract; Lenses, Intraocular
PubMed: 37931117
DOI: No ID Found -
American Journal of Ophthalmology Mar 2024Our aim was to evaluate whether patients with age-related macular degeneration (AMD) and cooccurrent amblyopia are more likely to have diseases diagnosed on both the...
PURPOSE
Our aim was to evaluate whether patients with age-related macular degeneration (AMD) and cooccurrent amblyopia are more likely to have diseases diagnosed on both the ipsilateral and the contralateral side in a large Austrian database.
DESIGN
Retrospective cross-sectional study.
METHODS
Setting: Institutional practice.
PATIENT POPULATION
Medical records of all patients who visited the Department of Ophthalmology of the Medical University of Graz between December 1996 and June 2021 were searched for the co-occurrence of AMD and amblyopia.
MAIN OUTCOME MEASURES
Data from patients with AMD diagnosed on 1 eye side were used for further analysis. Spectral-domain optical coherence tomography images were analyzed to confirm the lateral asymmetry of AMD.
RESULTS
A total of 327,443 patients were screened for the co-occurrence of AMD and amblyopia. Of them, 8742 patients had AMD diagnosed on 1 eye side and 5051 patients had unilateral amblyopia. In total, 163 patients were found to have AMD diagnosed on 1 side and unilateral amblyopia in combination. Of these, 126 patients had AMD and amblyopia on contralateral sides and 37 had AMD and amblyopia on the ipsilateral side (P < .001).
CONCLUSIONS
Less amblyopic patients had AMD diagnosed on the amblyopic eye compared with the nonamblyopic eye. In cases of lateral asymmetry, the nonamblyopic eye is more likely to have the more advanced form of AMD.
Topics: Humans; Amblyopia; Visual Acuity; Retrospective Studies; Cross-Sectional Studies; Macular Degeneration; Tomography, Optical Coherence
PubMed: 37437833
DOI: 10.1016/j.ajo.2023.07.006 -
BMC Ophthalmology Sep 2023To observe and understand the structural changes in choroidal vessels in eyes with hyperopic anisometropic amblyopia using swept-source optical coherence tomography...
PURPOSE
To observe and understand the structural changes in choroidal vessels in eyes with hyperopic anisometropic amblyopia using swept-source optical coherence tomography angiography (SS-OCTA).
METHODS
A total of 44 patients were enrolled in this study: 22 children with hyperopic anisometropic amblyopia and 22 age-matched controls. SS-OCTA was used to scan the 6*6 mm macular area of their eyes. The average choroidal thickness (CT) and choroidal capillary flow area (CC) in a 3 mm diameter area centered on the macular area were obtained. The choroidal vascularity volume (CVV) was automatically extracted and 3D reconstructed by inbuild software, and the three-dimensional choroidal vascularity index (3D-CVI) was calculated. The effect of amblyopia on the choroidal vessel structure was assessed using generalized linear estimating equations (GEEs) corrected for axial length, sex, age, and best-corrected visual acuity.
RESULTS
The CC was greater in amblyopic eyes than in fellow eyes (P = 0.014) but was not significantly different from that in control eyes (P = 0.963). After correcting for sex, age, axial length, and visual acuity using GEEs, the mean CT in the amblyopic eyes was greater than that in the fellow eyes (P = 0.030) but was not significantly different from that in the control eyes (P = 0.160). The 3D-CVI in amblyopic eyes was higher than that in control eyes (P = 0.038) but was not significantly different from that in fellow eyes (P = 0.407). The three-dimensional choroidal vascularity volume (3D-CVV) was higher in amblyopic eyes than in fellow eyes (P = 0.046) and control eyes (P = 0.023).
CONCLUSIONS
We found that eyes with hyperopic anisometropic amblyopia demonstrated higher CT, CC and 3D-CVV values than the contralateral eyes after correction, while the 3D-CVI was unchanged. Compared with control eyes, amblyopic eyes had higher 3D-CVV and 3D-CVI values but similar CT and CC values. Amblyopic eyes may have different choroidal vascular structures from fellow and control eyes.
Topics: Child; Humans; Amblyopia; Tomography, Optical Coherence; Anisometropia; Hyperopia; Choroid; Angiography
PubMed: 37723524
DOI: 10.1186/s12886-023-03121-x -
Journal of Clinical Medicine Sep 2023(1) Background: Patients with unicoronal craniosynostosis (UCS) often show torticollis which can result from either an ocular cause or contraction of the...
(1) Background: Patients with unicoronal craniosynostosis (UCS) often show torticollis which can result from either an ocular cause or contraction of the sternocleidomastoid muscle. For clinicians, it is crucial to know the prevalence of ocular torticollis (OT) to ensure appropriate referral for treatment. Furthermore, associated ophthalmic features with OT in these patients are scarcely described. The aim of this study was to determine the prevalence of OT in non-syndromic UCS patients and investigate its associated ophthalmic features. (2) Methods: In this descriptive cross-sectional study medical records of non-syndromic UCS patients treated between 1994-2022 in one tertiary care hospital in The Netherlands were retrospectively reviewed. Collected data included: diagnosis and type of torticollis, binocular single vision (BSV), strabismus, ocular motility, alphabetical patterns, refractive error, and amblyopia. Patients were classified as OT, based on their ophthalmic and/or orthoptic diagnosis. Prevalence was determined with the 95% CI using the Clopper-Pearson exact test. Associations between OT and the ophthalmic features were determined using Chi-square or Fishers' exact test and its effect size was calculated using Cramer's V. (3) Results: In total, 146 patients were included, of whom 57 had torticollis. An ocular cause for the torticollis was found in 54 patients. The prevalence of OT was 37% (n = 146; 95% CI [0.292-0.454]). Significant associations were found between OT and strabismus ( < 0.001), ocular motility abnormalities ( < 0.001), alphabetical patterns ( < 0.001), and amblyopia ( = 0.002). BSV ( = 0.277) and refractive error ( = 1.0) were not significantly associated with OT. However, in OT the BSV was relatively poor (42.1%) and more frequently absent (26.3%) compared to the non-torticollis group (7% poor and 16.3% absent). In both groups, excyclotorsion was predominantly present (62.3%). (4) Conclusions: In 95% of cases, torticollis in UCS patients is ocular-related. Overall, one in three patients with UCS have OT. This study emphasizes the importance of a timely referral of all patients with UCS with torticollis to an orthoptist and/or ophthalmologist, specialized in diagnosing and treatment of OT, before considering physiotherapy.
PubMed: 37762999
DOI: 10.3390/jcm12186059 -
Heliyon Apr 2024To explore the association between the cause of amblyopia and pre-treatment contrast sensitivity, stereoacuity, fixation and nystagmus.
PURPOSE
To explore the association between the cause of amblyopia and pre-treatment contrast sensitivity, stereoacuity, fixation and nystagmus.
DESIGN
Retrospective cohort study.
METHODS
A retrospective review was conducted for 3408 patients with amblyopia who had not yet started amblyopia treatment utilizing a large amblyopia patient database maintained at Zhongshan Ophthalmic Centre. Six amblyogenic factor subtypes were identified: anisometropia, isoametropia, strabismus, anisometropia and strabismus, monocular visual deprivation, and binocular visual deprivation amblyopia. Monocular best corrected visual acuity (BCVA), the contrast sensitivity function (CSF), fixation, and stereopsis were compared between the subtypes before and after propensity score matching (PSM) for age and sex.
RESULTS
The two deprivation groups had poorer BCVA and CSF than the other groups. There were no systematic differences in CSF between the non-deprivation groups. Nystagmus was more common in the bilateral amblyopia groups compared to the monocular amblyopia groups. Eccentric fixation was uncommon with the exception of the anisometropia and strabismus group which had an eccentric fixation rate of 20%. Distance stereoacuity measured without monocular cues was absent for almost all patients. The results were consistent when analyzed using PSM.
CONCLUSION
Visual deprivation causes more severe amblyopia than other amblyogenic factors. For non-deprivation amblyopia subtypes, individual differences such as variation in the severity of the amblyogenic factor might be more important in determining pre-treatment vision than whether amblyopia was caused by refractive error, strabismus or both.
PubMed: 38596124
DOI: 10.1016/j.heliyon.2024.e28857 -
Turkish Journal of Ophthalmology Aug 2023This study aimed to examine factors associated with strabismus in patients with retinopathy of prematurity (ROP) and the relationship between strabismus and macular...
OBJECTIVES
This study aimed to examine factors associated with strabismus in patients with retinopathy of prematurity (ROP) and the relationship between strabismus and macular ectopia.
MATERIALS AND METHODS
Patients with ROP were divided into three groups: Group 1, patients with spontaneous regression (n=45); Group 2, patients who received laser treatment (n=70); and Group 3, patients who underwent surgical treatment (n=91). Rates of anisometropia, amblyopia, nystagmus, macular ectopia, and retinal pathologies were evaluated and their impacts on strabismus development were determined. Disc-to-fovea distance (DFD) was measured from color fundus photographs and the correlation of macular ectopia with severity of strabismus was evaluated.
RESULTS
A total of 206 patients were included. Rates of anisometropia, amblyopia, nystagmus, macular ectopia, retinal pathologies causing vision loss, and strabismus were higher in Group 3 (p=0.0001) and correlated with higher stages of ROP (p=0.0001). Macular ectopia (p=0.005), retinal pathologies (p=0.005), and amblyopia (p=0.012) had the strongest impact on strabismus development in ROP patients. DFD and strabismus severity were not significantly correlated (p=0.364). Mean visual acuity (VA) was significantly higher in orthophoric patients compared to those with esotropia and exotropia (p=0.027). Esotropic patients had lower VA compared to patients with exotropia, but this finding was not statistically significant (p=0.729).
CONCLUSION
Presence of macular ectopia, retinal pathologies, and amblyopia were the most strongly correlated risk factors for strabismus development in ROP patients. DFD was not associated with severity of strabismus. Exotropia was mostly related to higher DFD and a possible relationship between esotropia and lower VA was observed.
Topics: Infant, Newborn; Humans; Retinopathy of Prematurity; Amblyopia; Esotropia; Exotropia; Anisometropia; Strabismus
PubMed: 37602650
DOI: 10.4274/tjo.galenos.2023.48310