Ocular Misalignment Research Articles

A preliminary exploration of quantitative models for evaluating binocular visual perception impairments among patients diagnosed with stroke.

The objective of this study is to formulate and implement graded biological models pertaining to binocular visual perception function with the use of computer algorithms. We aim to quantitatively assess the location, severity, and degree of impairment in binocular visual perception among patients who have suffered stroke, thereby providing valuable insights into the repercussions of cerebral tissue damage on the visual system. To overcome the shortcomings of previous instruments used to assess binocular function in terms of stereoscopic effects and the challenges posed by physiological and psychological interference during examinations, this study optimized its approach by integrating polarized stereovision technology with computer graphic modeling techniques. This study employed computer models to assess binocular visual perception function in stroke patients. Computer models refer to psychophysical testing methods used to measure binocular visual perception function, including various assessment tasks such as recognizing inverted letters and assessing stereopsis during high-speed movements. The cross-into-circle test was used as a means to quantify perceptual eye position. Subsequently, the collected data was analyzed to assess the magnitude of impairment in binocular visual perception. The results of the study revealed a spectrum of binocular visual perception impairment among patients diagnosed with stroke, demonstrating discernible variations in the recognition of inverted letters and stereopsis across different movement speeds. Importantly, perceptual eye position measurements offered valuable insights into ocular misalignment. The computational models effectively quantified both the spatial distribution and severity of these identified impairments. Damage to brain tissue resulting from a stroke can give rise to notable impairments in binocular visual perception function. Graded biological models, formulated through computer algorithms, provide a systematic framework for the comprehensive evaluation and quantification of these impairments. The comprehension of the nature and extent of visual impairments observed in patients with stroke establishes a basis for the development of personalized visual perception learning methodologies. Based on such tailored approaches, we aim to facilitate the recovery of impaired visual function, thereby contributing to the broader objective of neural system rehabilitation.

Orbital Myositis and Strabismus: Clinical Profile, Management, and Predictive Factors for Recurrence.

To study the clinical profile of patients with orbital myositis and their management modalities and predictive factors for recurrence. The records of all consecutive patients diagnosed as having orbital myositis from 2010 to 2022 were reviewed. Patient demographics, presenting complaints, visual function, primary gaze deviation, and extraocular muscle involved were studied in the clinical profile. The radiological modalities and their management along with the recovery status and need for surgical intervention were documented. Fifty-two patients (55 eyes) (69% women) were diagnosed as having orbital myositis with a mean age of 36 ± 16 years presenting with periocular pain (55%) followed by diplopia (49%). Disease was unilateral in 94%. Sixty percent had ocular misalignment in primary gaze. The medial rectus was the most involved muscle (58%), with abduction limitation in 73%. Computed tomography (42%), magnetic resonance imaging (42%), and combined imaging (16%) were used in localizing the disease. Muscle biopsy was done in 38% of patients. Systemic immunomodulators were required in 16%. Strabismus surgery was planned in 15% of patients and done in 11%. Recurrence was noted in 43%. Abrupt cessation of steroids was a significant risk factor in recurrence of the disease (P = .046). Recovery was partial in 44% of patients and complete in 47%. Systemic steroids with slow taper has satisfactory outcomes in orbital myositis. Patients refractory to treatment ideally should undergo biopsy and begin taking steroid-sparing agents. Once the disease is in remission, residual disease can be surgically treated for better functional outcome. [J Pediatr Ophthalmol Strabismus. 20XX;X(X):XXX-XXX.].

Corneal Curvature Change After Strabismus Surgery: An Experience from a Single-academic Center

Objective: This study aimed to explore corneal curvature changes following strabismus surgery using a quadric surface fitting model to address ocular misalignment. Material and Methods: In this prospective cross-sectional study, 54 completed cases (84 eyes) of patients aged 6–60 years old (mean 10 years old) undergoing horizontal rectus muscle surgery were examined using placido-based keratometry with the Oculus Keratograph 5M system. Data on corneal curvature were collected one week pre-operation, and again one week, one month, and three months post-operation. Asphericity in the vertical meridian (Qy) and horizontal meridian (Qx), and surgical-induced astigmatism (SIA) were calculated. Results: The 84 eyes included were categorized into three groups: horizontal muscle surgeries, oblique muscle surgery, and combined horizontal and oblique muscle surgeries. Significant corneal prolation (steep central, flat peripheral) was revealed in the vertical meridian (Qy) at 3 months postoperatively for lateral rectus (LR) recession in the first group (p < 0.001), and the mean SIA was 0.45 D (95% CI: 0.35–0.56 D). A similar effect was seen in the vertical meridian of the third group (p < 0.01), with a mean SIA at 3 months of 0.27 D (95% CI: 0.23–0.32 D). Conclusion: Lateral rectus muscle recession induces corneal vertical prolation for up to 3 months post-operation. Surgeons are thus advised to re-evaluate refraction and defer contact lens refitting, refractive surgery, and intraocular lens calculations for at least 3 months after the procedure.

A case of bilateral straatsma syndrome

Straatsma syndrome is characterized by a constellation of conditions including amblyopia, nystagmus, and myopia. We present the case of a 10-year-old boy who complained of involuntary back-and-forth eye movements and reduced vision since birth. His visual acuity was measured at 2/60 in both eyes. Examination revealed horizontal pendular nystagmus without ocular misalignment. Fundus examination showed myopic changes, including an anomalous optic disc with extensive myelinated nerve fibers extending from the optic disc along the superior and inferior arcades to the fovea. Axial length measurements were 28.34 mm and 27.96 mm in the right and left eyes, respectively. SD-OCT imaging confirmed thickening of the retinal nerve fiber layer. Treatment included cycloplegic refraction and occlusion therapy, with regular follow-ups every three months utilizing contact lenses with cycloplegic refraction. The etiology of retinal fiber myelination remains unclear; however, it is hypothesized that blurred retinal imaging during critical ocular development stages may lead to axial elongation and subsequent myopia, potentially delaying the development of the lamina cribrosa and facilitating myelination extension.

Molecular and physiological changes in the SpaceX Inspiration4 civilian crew

Human spaceflight has historically been managed by government agencies, such as in the NASA Twins Study1, but new commercial spaceflight opportunities have opened spaceflight to a broader population. In 2021, the SpaceX Inspiration4 mission launched the first all-civilian crew to low Earth orbit, which included the youngest American astronaut (aged 29), new in-flight experimental technologies (handheld ultrasound imaging, smartwatch wearables and immune profiling), ocular alignment measurements and new protocols for in-depth, multi-omic molecular and cellular profiling. Here we report the primary findings from the 3-day spaceflight mission, which induced a broad range of physiological and stress responses, neurovestibular changes indexed by ocular misalignment, and altered neurocognitive functioning, some of which match those of long-term spaceflight2, but almost all of which did not differ from baseline (pre-flight) after return to Earth. Overall, these preliminary civilian spaceflight data suggest that short-duration missions do not pose a significant health risk, and moreover present a rich opportunity to measure the earliest phases of adaptation to spaceflight in the human body at anatomical, cellular, physiological and cognitive levels. Finally, these methods and results lay the foundation for an open, rapidly expanding biomedical database for astronauts3, which can inform countermeasure development for both private and government-sponsored space missions.

The effect of teprotumumab infusion on ocular alignment in patients with symptomatic thyroid eye disease

BackgroundThyroid eye disease (TED) can result in proptosis and ocular misalignment, leading to eye pain, diplopia, and vision loss. Teprotumumab, a humanized antibody against insulin-like growth factor 1 receptor, was approved in 2020 for the treatment of TED. The purpose of this study was to describe the effect of a full course of teprotumumab on ocular misalignment. MethodsThe medical records of patients who underwent treatment with teprotumumab for active moderate-to-severe TED at a single institution from April 2020 to September 2023 were reviewed retroactively. Sensorimotor examination was performed at each visit using simultaneous prism-cover testing. Demographic information and previous history of radioactive iodine, steroids, strabismus surgery, and smoking were extracted from the record for analysis. ResultsA total of 19 patients were treated during the study period, of whom 11 had strabismus and diplopia. The initial absolute horizontal misalignment in these 11 was 6.0Δ ± 1.5Δ, vertical misalignment was 7.7Δ ± 2.4Δ, and total misalignment was 11.5Δ ± 2.0Δ. On completion of treatment, these measurements decreased by 2.0Δ ± 1.5Δ, 2.2Δ ± 1.0Δ, and 3.2Δ ± 1.6Δ, respectively (P = 0.10, 0.02, and 0.04, resp.). Eight patients (73%) had a decrease in their strabismus, and 5 (46%) reported complete resolution of their diplopia at the final visit. No factors were predictive of which patients would have resolution of their misalignment. Of the remaining 3 patients who had no improvement in ocular alignment, 2 (66%) underwent strabismus surgery. Of the 8 patients with improvement of strabismus, only a single patient (13%) underwent strabismus surgery for persistent diplopia. ConclusionsIn our study cohort, a full course of teprotumumab coincided with complete resolution of diplopia in 46% of patients and a decrease in strabismus in 73% of patients.

Using Smartphones to Enhance Vision Screening in Rural Areas: Pilot Study.

While it is treatable, uncorrected refractive error is the number one cause of visual impairment worldwide. This eye condition alone, or together with ocular misalignment, can also cause amblyopia, which is also treatable if detected early but still occurs in about 4% of the population. Mass vision screening is the first and most critical step to address these issues, but due to limited resources, vision screening in many rural areas remains a major challenge. We aimed to pilot-test the feasibility of using smartphone apps to enhance vision screening in areas where access to eye care is limited. A vision screening program was piggybacked on a charity summer camp program in a rural county in Sichuan, China. A total of 73 fourth and fifth graders were tested for visual acuity using a standard eye chart and were then tested for refractive error and heterophoria using 2 smartphone apps (a refraction app and a strabismus app, respectively) by nonprofessional personnel. A total of 5 of 73 (6.8%, 95% CI 2.3%-15.3%) students were found to have visual acuity worse than 20/20 (logarithm of minimal angle of resolution [logMAR] 0) in at least one eye. Among the 5 students, 3 primarily had refractive error according to the refraction app. The other 2 students had manifest strabismus (one with 72-prism diopter [PD] esotropia and one with 33-PD exotropia) according to the strabismus app. Students without manifest strabismus were also measured for phoria using the strabismus app in cover/uncover mode. The median phoria was 0.0-PD (IQR 2.9-PD esophoria to 2.2-PD exophoria). The results from this vision screening study are consistent with findings from other population-based vision screening studies in which conventional tools were used by ophthalmic professionals. The smartphone apps are promising and have the potential to be used in mass vision screenings for identifying risk factors for amblyopia and for myopia control. The smartphone apps may have significant implications for the future of low-cost vision care, particularly in resource-constrained and geographically remote areas.

Midbrain lesion-induced disconjugate gaze: A unifying circuit mechanism of ocular misalignment?

Midbrain lesion-induced disconjugate gaze: A unifying circuit mechanism of ocular misalignment?

Strabismus Surgery for Traumatic Ocular Misalignment: Twelve Cases in Five Years

Introduction : Trauma can cause an ocular misalignment due to damage of extraocular muscles, nerves and orbital tissue around the eye. Direct trauma causing extraocular muscle rupture needs immediate surgery, meanwhile indirect trauma resulting in traumatic sixth nerve palsy or other reversible ocular misalignment without orbital floor fracture can be observed for six months. This study describe the characteristic of patients undergo single-step strabismus surgery for traumatic ocular misalignment, mechanism of injury, eye alignment, amount of ocular deviation before and after strabismus surgery.
 Case Illustration : This was a case series based on medical record of patients underwent strabismus surgery secondary to head or eye injury from 2017 until 2022.
 Discussion : Twelve individuals with post-traumatic strabismus correction participated in this study. All subjects were male age ranging from 18-51 years. Direct trauma was observed in 6 (50%) patients causing medial rectus muscle rupture in 4 patients and inferior rectus muscle rupture in 2 patients. Indirect trauma was observed in 6 (50%) patients caused by sixth nerve palsy on 4 patients The misalignment was exotropia, esotropia, and hypertropia with amount of 5, 4, and 3 respectively. The deviation was between 30-90 prism dioptre (PD) and 7 (58%) patients had deviation less than 65 PD. Strabismus surgery performed was muscle transposition with or without recession of the antagonist muscle.
 Conclusion : Single step surgery for traumatic ocular misalignment can provide good result in cases of deviation less than 65 PD

Quality of Life Comparisons in Strabismic Children Managed Surgically or Conservatively

Abstract
 Introduction & Objectives : Strabismus causes visual impairment due to ocular misalignment, interferes cosmetic appearance, results in negative self-image and impacts quality of life. Studies in adults have shown that successful strabismus surgery improves quality of life, but awareness of strabismus surgery and its benefits are still lacking. Studies regarding the impact of conservative treatment on quality of life are limited, so further study is required.
 Methods : This was an observational study comparing 2 unpaired groups. The method used in this study was cross-sectional and samples were obtained purposefully according to medical records and consecutively based on outpatient visits.
 Results : Thirty-six subjects in group A, who had undergone strabismus surgery and 33 subjects in group B who were still managed conservatively were included in this study. Both groups had similar demographic characteristics, except parental education background (p=0.048). Comparative test of2 unpaired groups in this study showed higher quality of life scores in group A (p=0.0001).
 Conclusion : The quality of life in subjects who had undergone strabismus surgery was better than that in those who were still managed conservatively.

Knowledge and Awareness regarding Strabismus and Amblyopia among School Nurses and Primary School Teachers of Government Schools at Bharatpur

Background
 Strabismus/squint is an ocular misalignment in which the eyes are not properly aligned with each other. Amblyopia is a serious visual impairment resulting from abnormal visual stimulation during early childhood. It can be easily prevented or treated if detected early. This study aimed to assess the knowledge and attitude of school nurses and primary school teachers of Government schools toward children suffering from strabismus and amblyopia.
 Method
 This was a cross-sectional study among the participating school nurses and primary school teachers of Government school which was organized to raise awareness regarding strabismus and amblyopia among them. It was conducted using a questionnaire which contained 22 items divided into three sections. First section consisted of demographic parameters, second regarding knowledge of strabismus and the third the knowledge of Amblyopia. Data were analysed using Epi info version 7.02 (Centers for Disease Control, Atlanta, Georgia, United States). P-values of <0.05 was used for clinical significance.
 Result
 There were 67 participants and the mean age was 32.67±7.71 years, range 21 to 55 years, the majority being female 66 (98.51%). Training on eye health was received by 13 (19.40%). Forty-four (65.67%) participants had knowledge of strabismus and amblyopia, out of them 30 were school nurses. The majority of school nurses 23 (76.67%) and primary teachers 13 (92.86%) had good knowledge scores (6 to 10).
 Conclusion
 The majority of participants had good knowledge about strabismus and amblyopia. As the school nurses and primary school teachers are the first link to the children at risk, improving their awareness level on strabismus and amblyopia will help in early referral, timely intervention and prevent the risk of vision loss.

Scale for Ocular Motor Disorders in Ataxia (SODA) in Patients with Multiple System Atrophy.

A clinical scale fully dedicated to evaluating ocular motor abnormalities is required for now. We investigated the utility of a recently developed Scale for Ocular motor Disorders in Ataxia (SODA) in patients with multiple system atrophy (MSA). We prospectively assessed SODA in consecutive patients with MSA between August 2021 and August 2023 at the Korea University Medical Center. The results of the clinical exam-based SODA were compared with those measured using video-oculography (VOG-guided SODA). We also compared the findings with other established clinical scales targeting patients with MSA, including the Unified Multiple System Atrophy Rating Scale (UMSARS) I-II, Movement Disorder Society-Unified Parkinson's Disease Rating Scale motor part (UPDRS-III), Scale for Assessment of Rating of Ataxia (SARA), Composite Autonomic Symptom Score-31 (COMPASS-31), and Composite Autonomic Severity Score (CASS). Twenty patients were enrolled in our study (17 with cerebellar-type MSA and three with Parkinson-type MSA). Scores ranged from 1 to 14 (median [interquartile range (IQR)] = 8 [5-10]). Among the subscales, saccades had a median score of 2.5 (IQR = 1-3), followed by ocular pursuit (1 [0-1]), nystagmus (1 [0-2]), saccadic intrusions (1 [0-1]), vestibulo-ocular reflex (VOR) (0.5 [0-1]), ocular alignment (0 [0-1]), and VOR cancellation (1 [0-1]). The clinical-exam-based SODA (p = 0.020) and VOG-guided SODA (p = 0.034) positively correlated with disease duration. No correlation was found between clinical exam-based SODA and other scales. Skew deviation, gaze-evoked nystagmus, VOR cancellation, and smooth pursuit had the highest precision among the items. Ocular misalignment and spontaneous and positional nystagmus were frequently false positive and were poorly detected with clinical exam-based SODA. Six patients with repeated evaluation exhibited higher scores, along with deterioration documented on other clinical scales. The SODA can reliably predict neurodegeneration as an additional clinical surrogate in MSA.

Sagging Eye Syndrome--an Overlooked Diagnosis

Background: Sagging Eye Syndrome (SES) is a relatively unknown cause for binocular distance diplopia. SES presents with an acquired comitant or non-comitant small angle esotropia and/or hypotropia commonly occurring in the elderly population. Inferior displacement of the lateral rectus secondary to age-related degeneration of orbital connective tissue and extraocular muscles appears to be responsible for the ocular misalignment. SES patients often present with new onset or progressively worsening distance diplopia, typically warranting neuroimaging. However, through understanding SES, eye care practitioners may identify these cases, avoiding unnecessary imaging studies. Case Report: A 90-year-old male presented with complaints of intermittent horizontal diplopia at distance despite being prescribed prism for presumed decompensating phoria at his most recent eye exam. The patient noted progressing diplopia which appeared worse in right gaze. Full binocular examination revealed a non-comitant esotropia worse at distance than near. External exam revealed prominent deep superior sulci, blepharoptosis, and orbital fat loss bilaterally. Due to the progressive nature and incomitancy of the diplopia, a neuro-ophthalmology consult was obtained, and the patient was diagnosed with SES. A clinical diagnosis was made based on history, adnexal features, and motility patterns distinct to SES, obviating the need for confirmatory imaging. Conclusion: Patients presenting with new onset diplopia secondary to undiagnosed SES may prompt expensive and time-consuming investigations. It is critical that eye care practitioners accurately recognize the signs, symptoms, and clinical features of SES to avoid unwarranted imaging and patient anxiety. This case report reviews the clinical presentation, exam findings, and distinct picture of SES required for diagnosis and necessary to differentiate this condition from more serious neurologic conditions. Treatment and management will be discussed.

Eye Segmentation Method for Telehealth: Application to the Myasthenia Gravis Physical Examination.

Due to the precautions put in place during the COVID-19 pandemic, utilization of telemedicine has increased quickly for patient care and clinical trials. Unfortunately, teleconsultation is closer to a video conference than a medical consultation, with the current solutions setting the patient and doctor into an evaluation that relies entirely on a two-dimensional view of each other. We are developing a patented telehealth platform that assists with diagnostic testing of ocular manifestations of myasthenia gravis. We present a hybrid algorithm combining deep learning with computer vision to give quantitative metrics of ptosis and ocular muscle fatigue leading to eyelid droop and diplopia. The method works both on a fixed image and frame by frame of the video in real-time, allowing capture of dynamic muscular weakness during the examination. We then use signal processing and filtering to derive robust metrics of ptosis and l ocular misalignment. In our construction, we have prioritized the robustness of the method versus accuracy obtained in controlled conditions in order to provide a method that can operate in standard telehealth conditions. The approach is general and can be applied to many disorders of ocular motility and ptosis.

Feasibility study of an automated Strabismus screening Test using Augmented Reality and Eye-tracking (STARE)

BackgroundNew digital technologies (augmented reality headsets, eye-tracking) may potentially allow for automated assessments of ocular misalignment. Here, we evaluate the feasibility of a novel, open-source strabismus test (“STARE”) as an automated screening tool.MethodsWork progressed in 2 phases. In phase 1 (“development”), we used Fresnel prisms to elicit horizontal misalignments of known magnitude (1–40 prism dioptres) in orthotropic controls. In phase 2 (“validation”), we applied the system to adults with an established diagnosis of strabismus, and quantified the ability of the test to distinguish between those with horizontal misalignment and those without. Agreement between the alternate prism cover test measurements and STARE measurements was computed using Bland–Altman plots and product-moment correlation coefficients.ResultsSeven orthotropic controls and nineteen patients with strabismus were recruited (mean age 58.7 ± 22.4 years). STARE was able to identify the presence of horizontal strabismus with an area under the curve of 1.00 (100% sensitivity and 100% specificity). The mean difference (bias) {95% CI} was 2.1 {−1.8, 9.9} prism dioptres, and the 95% coefficient of repeatability {95% CI} was ±27.9 {14.8, 50.8} prism dioptres. The Pearson correlation between APCT and STARE was r24 = 0.62, P < 0.001.ConclusionsSTARE shows promise as a simple, automated tool for performing a screening assessment of strabismus. It is a rapid (60 s) test that can be performed using a consumer augmented reality headset with integrated eye-tracking, and might conceivably be used remotely by non-specialists in future as a means of highlighting individuals needing face-to-face specialist care.

Traumatic Brain Injury and Vision.

Traumatic brain injury disrupts the complex anatomy of the afferent and efferent visual pathways. Injury to the afferent pathway can result in vision loss, visual field deficits, and photophobia. Injury to the efferent pathway primarily causes eye movement abnormalities resulting in ocular misalignment and double vision. Injury to both the afferent and efferent systems can result in significant visual disability.

A Quantitative Approach to Telemedicine Assessment of Ptosis and Ocular Motility for Patients with Myasthenia Gravis (P7-8.011)

<h3>Objective:</h3> The study assessed the capability to quantify eye movements and lid position in patients with MG. <h3>Background:</h3> Ptosis and diplopia are nearly uniformly present in patients with myasthenia gravis (MG). In the telemedicine setting, the unique presence of video capture lends use of emerging implementation of image-processing techniques that could provide precise, standardized assessment of ocular motility abnormalities. <h3>Design/Methods:</h3> We utilized video recordings of the ADAPT teleMG study performed. Six subjects underwent standardized video examinations on two occasions 2–3 days apart. We performed a hybrid algorithm combining deep learning with computer vision to give quantitative metrics of ptosis and ocular motility. <h3>Results:</h3> All videos and still images could be used for analysis despite limitations of low resolution dictated by internet bandwidth and cameras of the examiner and subject. The hybrid algorithm detected the distance between pupil and upper eyelid for ptosis and misalignment of the left and right pupil for diplopia assessment. The algorithm automatically detected the pupillary and lid margins with error of 2 pixels in average. Lid, pupil, and iris detection did not differ based on skin or iris color. We were able to detect ocular misalignment in subjects complaining of diplopia. The method worked both on a fixed image and video in real-time allowing capture of the dynamic changes during the examination. <h3>Conclusions:</h3> We were able to use standard Zoom recordings of lid and eye movements and quantitate them using a hybrid deep learning computer vision algorithm. The system introduces modern image processing technique that are quick and robust to recover quantitative metrics that are independent of the examiner and would work on most video resolutions. The approach has the potential to quantitate ocular motility abnormalities and could be used to monitor patients. <b>Disclosure:</b> Mr. Lesport has nothing to disclose. Dr. Joerger has nothing to disclose. The institution of Dr. Kaminski has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Roche. Dr. Kaminski has received personal compensation in the range of $500-$4,999 for serving as a Consultant for UCB. Dr. Kaminski has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Cabaletta Bio. Dr. Kaminski has stock in ARC Biotechnology. The institution of Dr. Kaminski has received research support from National Institutes of Health. Dr. Kaminski has received publishing royalties from a publication relating to health care. Helen Girma has nothing to disclose. Ms. McNett has nothing to disclose. Dr. Abu-Rub has nothing to disclose. Prof. Garbey has stock in Care Constitution, LLC. Prof. Garbey has a non-compensated relationship as a CEO with Care Constitution, LLC that is relevant to AAN interests or activities.

27 Measuring Ocular Misalignment by Age at Space Center Houston to Inform Spaceflight Analysis

OBJECTIVES/GOALS: We developed a non-invasive test of ocular alignment (OA) as a measure of otolith asymmetry, which impacts vestibular function. This test has also been administered on commercial astronauts to study the effect of microgravity on vestibular function. We will assess OA test performance in ground subjects, which has not yet been characterized. METHODS/STUDY POPULATION: Subjects were recruited from visitors to Space Center Houston from June to October 2022. Participants wore red-blue glasses in a darkened room and aligned two vertically or torsionally misaligned line segments, one red and one blue, on a tablet. Each subject underwent 11 vertical and torsional trials. The remaining misalignment was used to calculate ocular misalignment. Subjects self-reported demographic and health data. We calculated descriptive statistics and explored the distribution of overall vertical and torsional OA and distributions by age. Next steps will establish the reliability of the outcome measures with intraclass correlation coefficients and analyze associations between demographic variables and health status with OA performance using linear regression analysis. RESULTS/ANTICIPATED RESULTS: A total of 143 participants (67 female) with a median age of 21 (range 5-74 years old) completed OA testing. Of participants, 64% identified as white, 10% as black, 14% as Asian, 3% as Native American, and 8% as unknown. This test battery was feasible to implement in this mixed-age sample, with a 95% completion rate. Median absolute vertical OA was 0.08 degrees (IQR = 0.17 degrees), and median absolute torsional OA was 0.80 degrees (IQR = 1.20 degrees). Visual analysis of plots of OA by trial number reveals no apparent learning effect within subjects, though some individuals had considerable variation in performance. Average absolute vertical ocular misalignment increased modestly when plotted by age (fitted regression line b = 0.0032 degrees per year of age, p = 0.004), unadjusted for potential confounders. DISCUSSION/SIGNIFICANCE: Ocular alignment testing was feasible in a mixed-age general population sample. Our findings will expand understanding of how OA varies with age. These results will be used to create a normative database to compare and inform analysis of OA results from commercial spaceflights, which include individuals of varying age and health statuses.

Special Issue “Pediatric Eye Disease: Screening, Causes and Treatment”

Clinical manifestations and courses of eye diseases in children are profoundly variable, from minor irritations, pain, infections, inflammations, ocular misalignment, refractive errors and visual impairment, to permanent blindness [...].

Visual Crowding Reveals Field- and Axis-Specific Cortical Miswiring After Long-Term Axial Misalignment in Strabismic Patients Without Amblyopia.

Inspired by physiological and neuroimaging findings that revealed squint-induced modification of cortical volume and visual receptive field in early visual areas, we hypothesized that strabismic eyes without amblyopia manifest an increase in critical spacing of visual crowding, an essential bottleneck on object recognition and reliable psychophysical index of cortical organization. We used real-time eye tracking to ensure gaze-contingent display and examined visual crowding in patients with horizontal concomitant strabismus (both esotropia and exotropia) but without amblyopia and age-matched normal controls. Nineteen patients with exotropia (12 men, mean ± SD = 22.89 ± 7.82 years), 21 patients with esotropia (10 men, mean ± SD = 23.48 ± 6.95 years), and 14 age-matched normal controls (7 men, mean ± SD = 23.07 ± 1.07 years) participated in this study. We found that patients with strabismus without amblyopia showed significantly larger critical spacing with nasotemporal asymmetry in only the radial axis that related to the strabismus pattern, with exotropia exhibiting stronger temporal hemifield crowding and esotropia exhibiting stronger nasal hemifield crowding, in both the deviated and fixating eyes. Moreover, the magnitude of crowding change was related to the duration and degree of strabismic deviation. Using visual crowding as a psychophysical index of cortical organization, our study demonstrated significantly greater peripheral visual crowding with nasotemporal asymmetry in only the radial axis in patients with strabismus without amblyopia, indicating the existence of hemifield- and axis-specific miswiring of cortical processing in object recognition induced by long-term adaptation to ocular misalignment.