Strabism

PURPOSE: To measure visual crowding, an essential bottleneck on object recognition and reliable psychophysical index of cortex organization, in older children and adults with horizontal concomitant strabismus before and after strabismus surgery. METHODS: Using real-time eye tracking to ensure gaze-contingent display, we examined the peripheral visual crowding effects in older children and adults with horizontal concomitant strabismus but without amblyopia before and after strabismus surgery...

(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 ( n = 9), anisometropic ( n = 16) and mixed ( n = 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...

OBJECTIVE: To evaluate the macular microvascular changes using optical coherence tomographic angiography (OCT-A) in children with unilateral amblyopia and their reversibility during treatment. METHODS: Patients with unilateral strabismic or anisometropic amblyopia or residual amblyopia from early congenital cataract surgery, examined between October 2019 and March 2021, were included. Vessel density and perfusion density in the superficial capillary plexus and area, perimeter and circularity of the foveal avascular zone (FAZ) were analysed using OCT-A in amblyopic eyes, contralateral eyes and control group healthy eyes...

Fixation disparity is a small vergence error that does not disrupt fusion. Fixation disparity measures correlate with binocular symptoms. This paper covers methodological differences between clinical fixation disparity measurement devices, findings when objective and subjective fixation disparities are compared, and the potential impact of binocular capture on fixation disparity measurements.Fixation disparity is a small vergence error that occurs in non-strabismic individuals and does not disrupt fusion. This paper reviews clinical fixation disparity variables and their clinical diagnostic value...

INTRODUCTION: Visual function deficits are seen in amblyopic subjects during fellow and binocular viewing. The purpose of the study was to examine the relationship between Fixation Eye Movement (FEM) abnormalities and binocular contrast sensitivity and optotype acuity deficits in amblyopia. METHODS: We recruited 10 controls and 25 amblyopic subjects [Anisometropic = 6, Strabismic = 10, Mixed = 9]. We measured binocular contrast sensitivity at spatial frequencies 1,2, 4, 8, 12 and 16 and binocular and monocular optotype acuity using a staircase procedure...

BACKGROUND: The aim of this case report is to present the successful management of both diplopia and amblyopia in a specific clinical situation, demonstrating neuroplasticity of the visual system in an adult patient. Causes of diplopia include eye pathologies in monocular diplopia and ischemic ocular motor nerve palsies, sudden life-threatening and chronic conditions in central nervous system in binocular diplopia. Strabismic amblyopia and nonarteritic anterior ischemic optic neuropathy are quite often ophthalmic conditions, first one is caused by suppression during developmental period and the latter one by ischemia of the optic nerve in adults...

The optimal method of treatment for a child depends on the patient's age at the time of diagnosis, the onset and type of amblyopia, and the degree of compliance attainable. In deprivation amblyopia, the cause of visual impairment (e.g., cataract, ptosis) needs to be treated first, and then the disorder can be treated such as other types of amblyopia. Anisometropic amblyopia needs glasses first. In strabismic amblyopia, conventionally amblyopia should be treated first, and then strabismus corrected. Correction of strabismus will have little if any effect on the amblyopia, although the timing of surgery is controversial...

An elevated threshold for neuroplasticity limits visual gains with treatment of residual amblyopia in older children and adults. Acetylcholinesterase inhibitors (AChEI) can enable visual neuroplasticity and promote recovery from amblyopia in adult mice. Motivated by these promising findings, we sought to determine whether donepezil, a commercially available AChEI, can enable recovery in older children and adults with residual amblyopia. In this open-label pilot efficacy study, 16 participants (mean age 16 years; range 9-37 years) with residual anisometropic and/or strabismic amblyopia were treated with daily oral donepezil for 12 weeks...

PURPOSE: To evaluate associations of socio-demographic factors with pediatric strabismus diagnosis and outcomes. DESIGN: Retrospective cohort study. SUBJECTS: American Academy of Ophthalmology IRIS® Registry (Intelligent Research in Sight) patients with strabismus diagnosed before age of 10 years old. METHODS: Multivariable regression models evaluated associations of race and ethnicity, insurance, population density and ophthalmologist ratio with age at strabismus diagnosis, diagnosis of amblyopia, residual amblyopia, and strabismus surgery...

PURPOSE: This is an observational, non-invasive study which measures the VEPs of twelve individuals, at baseline, and under the effect of six monochromatic filters used in visual therapy, to understand their effect on neural activity to propose successful treatments. METHODS: Monochromatic filters were chosen to represent the visible light spectrum, going from red to violet color, 440.5-731 nm, and light transmittance from 19 to 89.17%. Two of the participants presented accommodative esotropia...

People with amblyopia demonstrate a reduced ability to judge depth using stereopsis. Our understanding of this deficit is limited, as standard clinical stereo tests may not be suited to give a quantitative account of the residual stereo ability in amblyopia. In this study we used a stereo test designed specifically for that purpose. Participants identified the location of a disparity-defined odd-one-out target within a random-dot display. We tested 29 amblyopic (3 strabismic, 17 anisometropic, 9 mixed) participants and 17 control participants...

Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention. Previous clinical and neuroimaging studies have suggested that the neural mechanisms underlying strabismic amblyopia and anisometropic amblyopia may be different. Therefore, we performed a systematic review of magnetic resonance imaging studies investigating brain alterations in patients with these two subtypes of amblyopia; this study is registered with PROSPERO (registration ID: CRD42022349191)...

PURPOSE: To compare visual outcomes of standard occlusion therapy at home versus clinic in amblyopic children. METHODS: A retrospective study of case records of children aged <15 years with diagnosis of strabismic or anisometropic amblyopia or both was conducted at a tertiary eye hospital located in rural North India between Jan 2017-Jan 2020. Those with at least 1 follow-up visit were included. Children with ocular co-morbidities were excluded. Treatment in clinic by admission or at home was based on the parents' discretion...

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...

PURPOSE: To investigate the relationship between clinical features and protein amounts of Cysteine-rich 61 (Cyr61/CCN1) and connective tissue growth factor (CTGF/CCN2), which are vital components and regulators of the extracellular matrix in resected muscles from strabismus surgery. METHODS: Strabismus patients who were diagnosed with horizontal concomitant strabismus or inferior oblique overaction (IOOA) and required extraocular muscles (EOMs) resection to correct eye position were included in this study...

PURPOSE: To report the ophthalmic findings and ocular complications in a large cohort of pediatric patients with facial nerve palsy (FNP). METHODS: Ocular data of children (≤16 years of age) diagnosed with FNP presenting to an eye care network from 2012 to 2021 were analyzed. Study parameters were etiology of FNP, ocular and imaging findings, degree of lagophthalmos, and degree of vision loss. Clinical characteristics were compared between those with and without moderate-to-severe vision impairment (best-corrected visual acuity <20/50) and those with and without exposure keratopathy at presentation...

BACKGROUND: Childhood ocular disease can be a significant health burden to the child, family and society. Previous studies have examined the spectrum of paediatric ocular disease presenting to tertiary hospitals; however, these studies have broader age ranges, smaller sample sizes, and are largely based in developing countries. This study aims to assess the spectrum of ocular disease in the first 3 years of life presenting to the eye department of an Australian tertiary paediatric hospital...

Objective: The rationale of study was to find the magnitude of amblyopia with reference to type of squint among the strabismus patients visiting Hayatabad Medical Complex Peshawar, Pakistan. Materials and Methods: After ethical approval, a cross sectional study was carried out in the Department of Ophthalmology, Hayatabad Medical Complex, Peshawar, Pakistan, from April 2022 to October 2022, the total number of patients included being 237. Results: Amblyopia was observed in 113 out of 160 (70.6%) cases of uniocular squint, while in alternating squint it was found to be 11 out of 77 (14...

BACKGROUND: To explore the retinal microvasculature in large-angle concomitant exotropia patients with abnormal binocular vision using optical coherence tomography angiography (OCTA) analysis. METHODS: OCTA images of 52 healthy and 100 strabismic eyes were analyzed to quantify the retinal thickness (RT), superficial capillary plexus (SCP), deep capillary plexus (DCP), and foveal avascular zone (FAZ). Paired t-tests were performed to compare differences between the two groups, the dominant eye and the deviated eye in the exotropia group, respectively...

OBJECTIVES: To describe the etiologies of binocular diplopia for patients presenting to the ophthalmologic emergency department of the Regional University Center Hospital (CHRU) of Tours. METHODS: This is a retrospective study of the medical records of patients who presented with binocular diplopia in the ophthalmic emergency department of the CHRU of Tours between January 1st and December 31st, 2019. Binocular diplopia was classified as paralytic or non-paralytic according to the ocular motility examination...