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Purpose

To evaluate the diagnostic accuracy of the neos device — a head-mounted display with integrated eye tracking — for objective detection of binocular vision via disparity-induced vergence responses.

Methods

In this retrospective case series, 50 patients from a tertiary neuro-ophthalmology and strabismus centre (June 2025 – February 2026) underwent neos examination, including fusional amplitude measurement. Clinical binocular status was independently determined using standard tests (Bagolini striated glasses, Lang and TNO stereotests). A blinded grader then assessed neos pdf-reports alone, classifying binocular status based on the presence or absence of a motor vergence response. Diagnostic accuracy was quantified using sensitivity, specificity, and Cohen’s kappa coefficient.

Results

neos correctly identified 31 of 33 patients with binocular vision and 11 of 17 without. Observed accuracy was 84.0 %, with sensitivity of 93.9 % and specificity of 64.7 %. Cohen’s kappa indicated substantial agreement with clinical assessment (κ = 0.62, p < 0.001). False positives largely occurred in patients with intermittent strabismus, suggesting transient binocular function.

Conclusions

neos demonstrates good diagnostic accuracy for objective detection of binocular vision, particularly exhibiting high sensitivity. Its automated assessment could serve as a valuable screening tool for patients unable to complete conventional subjective tests. Prospective studies with larger cohorts are warranted to further validate clinical utility. 

Background

Infantile nystagmus syndrome (INS) is the most prevalent form of nystagmus encountered in ophthalmic practice. Today its diagnosis relies on clinical observations alone. Oculomotor characteristics have proven diagnostically but were only available in research settings. Here we test a recently introduced eye-movement recording device for its capacity to measure objectively all relevant features of infantile nystagmus syndrome.

Objective

To evaluate the diagnostic accuracy of the neos eye-movement recording system for detecting INS in an ophthalmic practice, and to compare performance between an experienced neuro-ophthalmologist and a novice reviewer. Methods Retrospective cross-sectional single-centre case series. All patients with a diagnosis containing the keyword "nystagmus", a successful neos recording and informed consent were included. Two blinded reviewers — an expert with >20 years' experience and a trained novice — independently classified each recording as INS, neurological nystagmus, other nystagmus, or healthy, based solely on the neos PDF report. Clinical diagnosis from routine tertiary care served as the reference standard. Sensitivity, specificity, accuracy, and Cohen's kappa (κ) were calculated.

Results

>60 patients were included. Expert review achieved a sensitivity of 83.3%, specificity of 100%, accuracy of 95.3%, and κ = 0.88 (almost perfect agreement; p < 0.0001). Novice review yielded a sensitivity of 61.1%, specificity of 97.8%, accuracy of 87.5%, and κ = 0.66 (substantial agreement; p < 0.0001).

Conclusions

The neos device enables accurate, objective detection of INS from a certified medical device in an ophthalmic setting — a first for this clinical context. Expert review performance was almost perfect. Even brief novice training yielded substantial agreement, suggesting potential for broader clinical deployment. Prospective validation in larger multicentre cohorts is warranted. 

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Purpose

The diagnosis of congenital stationary night blindness (CSNB) may be difficult as retinal structure is relatively preserved. This case report shows how pupillography using a commercially available medical device may differentiate CSNB from retinitis pigmentosa and healthy.  

Methods

A 7-year-old with moderate myopia and subnormal vision despite correction presented with difficulty in darkness. Optical coherence tomography was unremarkable. ERG showed the typical pattern of CSNB. Pupillary responses were assessed using a head-mounted pupillometry system (neos®) measuring light response amplitude and responses to darkness onset. Data were then compared to an age-matched healthy control and a patient with retinitis pigmentosa.

Results

Both CSNB and retinitis pigmentosa patients exhibited reduced pupillary light response amplitudes compared to the healthy control. At darkness onset, the CSNB patient demonstrated a paradoxical transient miosis followed by delayed mydriasis, whereas the retinitis pigmentosa patient and healthy control showed immediate dilation.

Conclusion

Pupillometry revealed a distinct functional signature in CSNB, characterized by reduced light response amplitude with occasional paradoxical constriction at darkness onset. While reduced amplitude is non-specific, the paradoxical dark response may represent a potential disease-specific marker. Pupillometry may therefore serve as a rapid and accessible adjunctive option for the evaluation of suspected CSNB, particularly when ERG is unavailable. Further studies are needed to establish its diagnostic performance. 

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Introduction
To develop and evaluate AI models for Parkinson’s disease (PD) diagnosis using quantitative VR-derived ocular motor and pupillary measurements.

Methods
102 PD patients were recruited in Zurich and Exeter; 89 PD patients were analysed.
133 individual PD examinations and 87 healthy-control examinations were included after curation.
PD and control examinations were propensity matched on age and sex, treating each examination as separate data points.
Participants completed standardized VR-based ocular motor assessments with the neos medical device and clinical examinations.
Seven AI models were trained. Model training, feature selection, hyperparameter optimisation, and calibration were performed within a nested cross-validation framework.
Eye-movement domains assessed: fixation/alignment, pupil dynamics, saccades, smooth pursuit, and vergence.

Conclusion
Ocular motor and pupillometric features acquired with the neos medical device enable high-accuracy discrimination of Parkinson’s disease from healthy controls across multiple AI-modelling approaches.

These findings support quantitative eye-movement assessment as a scalable, objective tool that may enhance PD diagnosis.

A diagnostic accuracy study is needed to validate this modeling approach and establish clinical utility.

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Introduction

Diagnosis of infantile nystagmus syndrome (INS) is usually based on manual examination, dependent on examiner experience. Objective and quantitative measures may ease diagnosis.

Objective

To evaluate the diagnostic accuracy of the neos clas IIa eye-movement recording system for detecting INS in a tertiary ophthalmic practice.

Methods

• Retrospective cross-sectional case series
• Inclusion: patients with and without nystagmus diagnosis
• Analysis: expert and novice blinded reviewers classified each recording as INS, neurological nystagmus, other nystagmus, or healthy, based solely on the neos PDF report. Clinical diagnosis from routine tertiary served as reference. Sensitivity, specificity, accuracy, and Cohen's kappa (k) were calculated.

Results

• Sixty-four patients included, 18 INS, 46 non-INS (11 other nystagmus, 35 non-nystagmus)

Conclusion /Discussion

Diagnostic accuracy was high, even in a novice with only 5 minutes of training. neos-based eye movement recording and report review enables accurate, objective  detection of INS in an ophthalmic practice setting. This represents the first demonstration of a certified medical device capable of addressing all core diagnostic criteria of INS. 

Introduction

Relative afferent pupillary defect (RAPD) is a key clinical sign of asymmetric optic nerve dysfunction. Its assessment is limited by the subjectivity of clinical examination and the restricted sensitivity of structural imaging using optical coherence tomography (OCT), 
particularly in the acute phase. In the absence of a reliable gold standard, discordance between clinical, structural, and functional measures is expected. This study aimed to compare these  modalities and to assess the contribution of quantitative pupillometry as a continuous functional measure for interpreting RAPD under real-world diagnostic conditions.

Methods

Data from 520 subjects were analyzed, including 132 healthy controls, 265 patients with multiple sclerosis–related disorders, 58 with other demyelinating diseases, and 38 with neurodegenerative conditions. RAPD was assessed clinically and quantified using the RAPD neoscore derived from binocular pupillometry (neos®, machineMD). Clinical RAPD assessment was derived from prospectively collected routine clinical documentation, reflecting real-world neurological practice rather than a standardized examination protocol within a clinical trial setting. Peripapillary retinal nerve fibre layer (pRNFL) thickness asymmetry was available in a subset of participants (n=103).
Abnormality was defined separately for each modality using predefined thresholds. Patterns of concordance and discordance between clinical assessment, RAPD neoscore, and OCT were analyzed to characterize complementary detection across modalities rather than accuracy against a reference standard.

Results

RAPD neoscore showed concordance with clinical RAPD assessment, demonstrating good discriminative performance relative to clinician impression (ROC AUC 0.82). In addition, functional afferent asymmetry as reflected by RAPD neoscore was observed in cases without OCT-detectable unilateral RNFL thinning, including cases with and without concordant clinical RAPD assessment. In clinically borderline or uncertain examinations, RAPD neoscore yields a continuous directional representation of afferent asymmetry without reliance on dichotomizing thresholds. Overall, overlap between modalities was partial, with each method identifying distinct but intersecting subsets of cases.

Conclusions

Clinical examination, structural OCT, and quantitative pupillometry capture different aspects of afferent visual pathway dysfunction, and no single modality provides a complete assessment of RAPD. In the absence of a definitive gold standard, analysis of detection overlap highlights the complementary nature of these approaches. RAPD neoscore contributes objective functional information beyond both clinical impression and structural imaging, supporting its role as a clinically useful adjunct in routine RAPD assessment, including situations characterized by diagnostic uncertainty.

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Purpose
Internuclear ophthalmoplegia (INO) is a characteristic ocular motor sign of multiple sclerosis (MS) resulting from small inflammatory lesions in the medial longitudinal fasciculus (MLF). Subtle variants, such as mild adduction slowing, frequently escape clinical detection. Virtual reality (VR)–based oculography enables objective and quantitative assessment of ocular motor function. This work evaluated whether a Versional Main-Sequence Index (VMSI), based on abducting–adducting asymmetry in the saccadic main-sequence velocity, can automatically detect INO when compared with expert ratings.

Methods
Eye movements were recorded with a commercially available medical device (neos/PRET, machineMD) during 10° and 20° horizontal saccades. Using all detected saccades for each eye, we estimated the main-sequence parameter k by fitting the relationship peak velocity = k sqrt(amplitude). The Versional Main-Sequence Index (VMSI) was defined as the ratio of the main-sequence parameter k for the abducting eye to k for the adducting eye. For comparison, two additional asymmetry measures were evaluated: Versional Dysconjugacy Index (VDI) area under the curve (AUC) and VDI peak velocity / amplitude (PV/AM). Binary INO classification used thresholds derived through ROC analysis.
Data were obtained from 687 participants (mean age 44.8 ± 14.4 years; range 18–83; 259 male/428 female), including 556 with neurological disease (predominantly MS subtypes) and 131 healthy controls. INO was rated as present by masked clinicians in 53 participants (right n=20, left n=16, bilateral n=17).

Results
VMSI-based classification achieved a maximum AUC of 0.97. Screening, balanced, and confirmatory thresholds were defined by ROC analysis within the same cohort, yielding sensitivities of 0.94/0.87/0.87 and specificities of 0.75/0.97/0.95, respectively. Misclassifications were primarily associated with high-noise recordings. VMSI outperformed VDI AUC, VDI PV/AM, and combinations of these metrics.

Conclusions
VR-based eye tracking enables objective, automated detection of INO using VMSI and shows strong discriminative performance relative to established asymmetry metrics. This approach may provide a quick, objective, and scalable functional biomarker of brainstem involvement in MS, complementing clinical examination and MRI.

Introduction

Parkinson’s disease (PD) diagnosis remains largely based on clinical evaluation, creating a need for objective and quantifiable biomarkers to enhance diagnostic accuracy, enable earlier detection, and support longitudinal monitoring. Eye movement and pupillary abnormalities are increasingly recognized as sensitive indicators of PD-related dysfunction in ocular motor control pathways. Advances in virtual reality (VR)–based eye tracking allow standardized measurement of such parameters (“oculometrics”) and provide promising inputs for artificial intelligence (AI)–driven classification models. This study aimed to develop and evaluate machine learning approaches for distinguishing PD from healthy individuals using quantitative ocular motor and pupillary metrics acquired with a VR-based medical eye-tracking device.

Methods

Individuals with idiopathic PD were recruited at two clinical centres: Zurich (Switzerland) and Exeter (United Kingdom). Participants completed two study visits including standardized VR-based ocular motor testing (neos®, machineMD) alongside routine clinical examinations. Recordings with poor tracking quality or excessive signal loss were excluded. The analysis included 132 PD examinations and 148 examinations from an independent healthy control dataset. Each PD case was matched to an age- and sex-matched control using a globally optimal matching algorithm. Group differences were quantified using standardized mean differences (SMDs) and Welch’s t-tests. A supervised machine learning classifier was trained using the most discriminative oculometric features to distinguish PD from controls. Model performance was assessed separately for each site.

Results

The strongest PD–control differences were observed in fixation instability, ocular alignment, blink rate, saccadic measures (accuracy, peak velocity, and main sequence relationships), and pupillary dynamics including constriction/dilation velocity and response latency. The classifier demonstrated high diagnostic discrimination across both sites, with combined AUROC of 0.94.

Discussion

These preliminary findings suggest that VR-derived oculometrics provide robust biomarkers capable of differentiating individuals with PD from healthy controls. AI-based analysis of ocular motor and pupillary features may offer a scalable and objective tool to complement clinical assessment. Future work will focus on expanding cohorts, integrating datasets across centres, and correlating oculometric parameters with clinical disease measures to further improve diagnostic performance.

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Objective:
The development of artificial intelligence (AI) models for diagnosing Parkinson’s disease (PD) using ocular motor parameters obtained from a virtual reality (VR)-based medical device.

Background:
PD diagnosis currently relies largely on clinical examination, underscoring the need for objective biomarkers to enhance diagnostic accuracy, early detection and disease monitoring. Eye movement and pupil function abnormalities have emerged as promising candidates, reflecting PD-related dysfunction in ocular motor control pathways.

Design/Methods:
Eighty-one patients with idiopathic PD were enrolled in Zurich (Switzerland) and Exeter (UK). Each participant underwent two visits, including standardized ocular motor testing with the VR-based medical eye tracker (neos®, machineMD) and corresponding manual examination. Data with poor tracking quality or excessive signal loss were excluded. The present analysis included 132 PD examinations and 148 healthy control examinations from an independent dataset. Each PD patient was matched to one control of similar age and sex using a globally optimal matching algorithm. For each parameter, standardized mean differences (SMDs) and Welch’s tests were computed. A supervised machine learning model was trained to classify PD versus controls based on the most discriminative parameters. Site-specific analyses were conducted for Zurich and Exeter.

Results:
Parameters showing the largest PD–control differences included saccades (accuracy, velocity, main sequence), vergence, ocular alignment, and pupil dynamics (constriction/dilation velocity and latency). The machine learning model achieved strong discrimination: Zurich—AUC 0.96 (F1: 0.92, sensitivity: 0.96, specificity: 0.89); Exeter—AUC 0.91 (F1: 0.84, sensitivity: 0.89, specificity: 0.79).

Conclusions:
Preliminary findings demonstrate that quantitative ocular motor and pupillary metrics can robustly distinguish PD from healthy individuals. Next steps include expanding the patient and control cohorts, merging datasets across sites, and correlating ocular motor parameters with clinical measures to refine diagnostic performance.

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Introduction

• Diabetic Retinopathy (DR) causes retinal ischemia, leading to impaired dark adaptation due to high oxygen demand.

• Hypothesis: Recovery of the pupillary light reflex (PLR) is delayed in DR patients compared with healthy controls.

Methods

• Design: Multi-center, non-interventional pilot study comparing PLR recovery in DR patients with healthy controls (HC) and retinitis pigmentosa (RP) patients (positive controls).

   

• Procedure: Pupillometry examination using the PRET™ VR headset (machineMD AG, Bern, Switzerland)⁵.

   

• Stimulus protocol: Alternating bright and dark stimuli across 50 cycles (dark phase increased by 100ms per cycle) while recording pupil size.

   

• Analysis: Linear regression and a linear mixed-effects model were used to test whether pupil responses at different time points and changes in PLR amplitude over time differ between groups.

   

Results

• Analysis included 10 patients with DR, 10 patients with RP, and 11 healthy controls.

• In all groups, PLR amplitude increased with longer dark adaptation across the 50 stimulus cycles (Fig. 2).

• Adaptation dynamics (Fig. 2) and maximal PLR amplitudes (Fig. 3) were significantly lower in DR and RP patients.

Conclusion

• PLR amplitudes may enable detection of DR using a simple pupillary test with a commercial VR headset, likely reflecting oxygen deprivation in DR.

• PLR may serve as a simple diagnostic test for retinal dystrophies, similar to ERG, but easier to perform.

Objectives: To validate the RAPD neoscore, a simple and objective metric for detecting RAPD, by comparing its diagnostic accuracy with traditional clinical evaluations.

Methods: A cohort of 164 individuals, comprising healthy controls and patients clinically diagnosed with RAPD, underwent neuro-ophthalmic evaluation using a PRET device (machineMD, Switzerland)³ alongside standard clinical assessments. Diagnoses included relapsing-remitting multiple sclerosis (RRMS, n=35), primary progressive multiple sclerosis (PPMS, n=2), secondary progressive multiple sclerosis (SPMS, n=2), and other demyelinating disorders (n=5). RAPD neoscore calculations were performed independently and blinded at a separate site. Diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis to determine sensitivity, specificity, and area under the curve (AUC).

Results: ROC analysis revealed an AUC of 0.80 ± 0.02 for RAPD neoscore across all RAPD cases. When clinically ambiguous cases were excluded, the discriminative performance improved, with an AUC of 0.83 ± 0.02, indicating good diagnostic accuracy.

Conclusions: The RAPD neoscore demonstrates robust agreement with traditional clinical assessments, highlighting its strong potential as a digital biomarker. Given the proposal to include optic nerve evaluation in diagnostic criteria for multiple sclerosis (MS), RAPD neoscore’s standardized and objective measurement could fulfill the dissemination-in-space criterion. This may significantly enhance diagnostic accuracy, facilitate monitoring, and support clinical decision-making in neuro-ophthalmology and multiple sclerosis diagnostics, ultimately improving patient outcomes.

Purpose: Eye and pupil movements are critical biomarkers for assessing neurological conditions. Most functional eye exams are manually performed making them subjective and error-prone; contributing to an estimated 50% misdiagnosis referral rates for neuro-ophthalmic conditions. neos™ (machineMD, Switzerland) is a novel virtual reality (VR) based measurement device, utilizing a head-mounted VR display and stimuli with infra-red eye tracking and proprietary algorithms to perform neuro-ophthalmological based tests in a non-invasive, automated, and quantitative way. However, validation of eye-tracking-based tools like neos™ poses inherent challenges, particularly in separating the device’s performance characteristics from those of the examinee. This study outlines a methodology to isolate and evaluate neos’s performance independent of external influences to ensure measurement reliability and robustness.

Methods: We evaluated neos’s gaze precision and pupil size measurement outputs independently using a customized eye-robot that simulates human eye movements and in human participants. We used test-retest reliability as a robust, calibration-independent surrogate metric of gaze precision of robot data that was further analyzed using intraclass correlation coefficients (ICCs), standard error of measurements (SEM), and Bland-Altman analysis. For human participants, we assessed pupil size by comparing neos’s eye tracker measurements and infrared images to visual light images calibrated with a physical scale, using the iris diameter as a reference.

Results:  In robotic trials, neos™ achieved excellent test-retest reliability for gaze precision (ICC > 0.99, SEM = 0.04), with high agreement between repeated measurements. Bland-Altman plots confirmed minimal bias and narrow variability across measurements, demonstrating robustness even in noisy conditions. Human trials revealed a mean pupil size difference of 0.38 ± 0.20 mm and iris size difference of 1.66 ± 0.38 mm between eye tracker and reference measurements.

Conclusions: The neos™ device has the potential to automate functional eye movement and pupil response measurements with high precision and minimal operator dependency, which can enhance neuro-ophthalmic diagnostic accuracy in clinical settings. Future studies will investigate its performance in detecting a range of specific biomarkers.

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Introduction

Acute anisocoria with ipsilateral ptosis, particularly when the pupillary asymmetry is greater in the dark, should raise suspicion for
Horner syndrome and prompt urgent evaluation for potentially life-threatening causes such as internal carotid artery (ICA) dissection. Early recognition in the neuro-ophthalmology setting is critical to prevent cerebral ischemic complications.

Case Report

• A 38-year-old woman presented with a smaller right pupil and mild right ptosis for 5 days, accompanied by right neck pain and facial pressure. She had recently been physically active. Exam showed right miosis (more pronounced in dim light) with briskly reactive pupils and mild ptosis.
• Pupillography (neos® system) demonstrated a clear right-sided dilatation lag, providing objective confirmation of oculosympathetic dysfunction. Pharmacological testing for Horner syndrome was not pursued because the lopidine test could not be realiably interpreted in cases of recent onset. 

• Contrast-enhanced computed tomography (CT) of the head and CT angiography (CTA) revealed a short-segment mural hematoma consistent with right ICA dissection, extending from the distal cervical segment to the transition into the petrous segment. No intracranial hemorrhage or cerebral ischemia was detected. 

Management

• The patient was admitted for monitoring and started on antiplatelet therapy with Aspirin 100mg.
• Cervical artery duplex ultrasound showed no significant stenosis
• With no signs of connective tissue disorder and a history of intense physical activity, the dissection was considered likely provoked.
• MR angiography (MRA) at 6-month follow-up showed normalization of the vessel lumen.

Discussion

• Acute Horner syndrome with ipsilateral neck/facial pain is a classic red flag for ICA dissection.
• As pupillary findings may be subtle, objective testing (e.g., pupillography) can support clinical suspicion, expedite emergency imaging, and occasionally a pharmacologic testing is not necessary any more due to the characteristic appearance with dilation lag in pupillography.
• Prompt vascular imaging with CTA or MRA is essential for diagnosis.
• Early antithrombotic therapy (antiplatelet or anticoagulaton, depending on clinical context) reduces thromboembolic and ischemic risk.
• Painful acute Horner syndrome should be treated as an emergency until ICA dissection is excluded.

Background: Persistent Postural-Perceptual Dizziness (PPPD) is a common chronic vertigo disorder triggered by postural changes, motion, and complex visual environments. The diagnostic criteria defined by the Bárány Society in 2017 are entirely subjective, and no objective biomarkers are currently available. This makes accurate diagnosis challenging, despite the condition’s substantial impact on quality of life. Optokinetic after-nystagmus (OKAN) has recently been proposed as a potential objective marker for visual dependence and functional vestibular disorders, including PPPD. However, traditional OKAN measurement techniques require specialized full-field optokinetic drums and are not feasible for routine clinical practice. The aim of this study is to determine whether Virtual Reality (VR) can reliably induced and measure the OKAN, and whether VR-derived OKAN parameters can distinguish PPPD patients from healthy controls. 

Methods: In this prospective cross-sectional pilot study, twelve healthy participants and thirteen PPPD patients underwent VR-based optokinetic stimulation with integrated eye-tracking⁵. The optokinetic stimulus consisted of a 40°/s full-field visual motion pattern presented for 60 seconds. All patients received standard clinical audiovestibular testing (vHIT, VNG, audiometry) and MRI. Outcome measures included OKAN presence, OKAN time constant (TC, s), OKN nystagmus score (%), test acceptability questionnaires (Likert /5) and test wellbeing questionnaires (Likert /5). 

Results: PPPD patients demonstrated significantly lower OKAN TC (3.05s vs. 19.72s in controls, p = 0.003) and lower OKN nystagmus scores (70.21% vs. 77.03% in controls, p = 0.032). The OKAN TC showed a sensitivity of 79% and a specificity of 83%. Test acceptability and wellbeing scores did not differ significantly between groups and consistently met predefined minimal viable product (MVP) thresholds (wellbeing: 3.0 vs. 3.3, MVP>3; acceptability: 4.3 vs. 4.7, MVP >4; both p > 0.05). 

Conclusion: The pilot study demonstrated that VR-based OKAN measurement is technically feasible, well tolerated, and enables OKAN assessment without specialized rotation chairs or optokinetic drums. The significant differences in optokinetic parameters between PPPD patients and healthy controls suggest that VR-OKAN could serve as a promising objective diagnostic tool. Further validation in larger and longitudinal cohorts is warranted to determine its clinical potential.

Purpose
Describe the utility of virtual perimetry in workup of patients with functional visual loss (FVL).

Methods
Retrospective review of 9 patients ages 19-60 years presenting with visual defects on automated perimetry due to functional visual loss. The patients presented with varied visual symptoms including abnormal automated perimetry in contrast to intact confrontational perimetry and normal structural exam. Virtual perimetry (neos®, machineMD) was performed and compared to automated perimetry.

Results
While standard automated perimetry revealed varied defects, VR perimetry documented largely normal visual fields, one patient had a deficit inconsistent with AF. 2 patients had monocular deficits on perimetry and normal virtual perimetry; 2 patients with monocular deficit on automated perimetry showed a homonymous pattern on virtual;1 patients with right homonymous defects on automated perimetry had normal virtual perimetry; 2 patient showed bilateral constriction AF with normal VR; 1 had central scotoma OU with normal VR; and 1 had variable deficits measured over time on AF with normal VR.

Conclusion
VR-based perimetry provides a novel tool for assessing visual function and may be a valuable adjunct in evaluating patients with suspected functional visual loss. The usefulness of virtual perimetry in functional patients may be related to a binocular paradigm with monocular data acquisition.

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Purpose
Concussion frequently disrupts visual pathways, making neuro-ophthalmic assessment critical for both diagnosis and monitoring recovery. The purpose of this case study is to describe what appears to be, after literature searches on PubMed and Google Scholar, one of the first reported cases of post-concussive Horner’s syndrome, as well as oculomotor dysfunction, and to illustrate its resolution using a virtual-reality (VR) neuro-ophthalmic diagnostic platform. 

Case Report
A 44-year-old man developed frontal-temporal headaches provoked by near-vision tasks—scrolling on phone, reading, and gaming—after a ball struck his face several months earlier. While the patient demonstrated normal best-corrected visual acuity, his initial examination revealed left-eye Horner’s syndrome (upper-lid ptosis, lower-lid “reverse” ptosis, anisocoria with dilation lag) and saccadic intrusions on near-point-of-convergence testing. Ocular health was otherwise unremarkable. 

VR-based neuro-ophthalmic testing showed a comitant eso deviation, left-eye dilation lag without relative afferent pupillary defect, saccadic inaccuracies and corrections, reduced saccadic velocity in down going saccades > up going saccades, saccadic intrusions and endgaze nystagmus during smooth pursuit, mildly inaccurate convergence beyond 5°, and limited divergence (≈1.5°). 

Six months later the clinical signs of Horner’s syndrome had completely resolved, along with some signs of oculomotor dysfunction. Repeat VR testing demonstrated normal pupillary function, more accurate saccades, fewer saccadic intrusions and less endgaze nystagmus on pursuits, improved convergence, and absent divergence fusion; vertical-saccade velocities were unchanged. 

Conclusion
This case demonstrates that Horner’s syndrome can occur as a transient sequela of concussion and may resolve within months. Serial assessment with a VR neuro-ophthalmic platform objectively captured both the presence and the resolution of sympathetic dysfunction as well as broader oculomotor recovery. This helps underscore the technology’s value in the diagnosis and monitoring of concussion and, by extension, more severe traumatic brain injury. 

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Introduction:  Virtual reality (VR) eye-tracking headsets are increasingly used in neuro-ophthalmology, allowing precise measurements in a controlled environment. This study evaluates their performance in measuring gaze direction and pupil size in children.

Methods:  For this study (swissethics-BASEC project-ID: 2023-D0055) 22 healthy children (12 female, 10 male; 3-12 years) and 145 adults and adolescents (76 female, 69 male, 13-92 years) were assessed with the VR- based medical eye-tracking device (neos®). The device examines oculomotor parameters by measuring pupil size and gaze directions. Descriptive statistics were conducted comparing the measurement precision in children with adolescents and adults.

Results:  The precision of gaze direction was lower in children (median 0.97°, 95th percentile 3.81°) compared with adolescents and adults (median 0.35°, 95th percentile 0.84°). Pupil size measurements were similarly precise in children (median 0.09 mm, 95th percentile 0.18 mm) compared with adolescents and adults (median 0.05 mm, 95th percentile 0.16 mm). Unstable eye-tracking and low task-compliance were more frequently observed in children than in adults and adolescents.

Conclusion/Relevance:  The VR-based neos™ eye-tracking system can be utilized for precise assessments of pupillary function in children, whereas the assessments relying on eye-gaze should be interpreted with caution. The measurement precision in children could further be improved by adapting the hardware to fit smaller heads better and by optimising the stimuli for children. Preliminary data in 20 children (with Galactosemia and healthy controls; swissethics-BASEC 202300714) support these findings and emphasize the need for larger pediatric studies. 

Introduction: Although frequently reported by Multiple Sclerosis patients (MS), it is hard to objectify subtle changes in oculomotor function. An objective measure of oculomotor involvement might represent a biomarker alleviating lesion localization, assessing disease progression and response to treatment. We applied a novel eye-tracking tool (PRET™, machineMD AG, Switzerland)³ to objectively assess a quantitative neuroophthalmological status in moderately to severely disabled MS and healthy controls (HC).

Objectives: We aim to i) demonstrate feasibility of PRET™ in neurological conditions and ii) provide an objective measure of deviations in primary gaze and horizontal/vertical saccades.

Methods: MS and HC were recruited for a pilot study using PRET™, a virtual reality (VR-)headset-based oculography tool (ethics approval no. 23-7934-BR, Ruhr-University Bochum). We examined MS with an expanded disability status scale (EDSS) of ⩾3.0 and sex- and age-matched HC. PRET™ runs an automated programme examining gaze holding and horizontal and vertical saccades, among other parameters not evaluated, here.
Descriptive statistics include median [interquartile range, IQR] and absolute frequencies. Fisher’s exact and Mann-Whitney test were used for comparisons. Exact p-values are given.

Results: We examined 17 MS (47.1 [41.2-56.6] years; n=12 female, n=5 male; n=12 relapsing-remitting MS (RRMS), n=4 secondary progressive MS (SPMS), n=1 primary progressive MS (PPMS); EDSS 4.0 [3.0-5.5]) and 17 HC (47.4 [40.5-56.1] years; n=12 female, n=5 male). None of HC and 8/17 MS reported subjective ocular complaints. All participants underwent PRET™ examination without patient-sided abortion due to discomfort or motion sickness. Primary gaze abnormalities were detected in 7/16 MS and 2/16 HC (data missing in n=1 each, p=0.1134). Saccadic abnormalities were present in 10/17 MS and 3/17 HC (p=0.0324), mostly driven by horizontal saccadic abnormalities, such as subtle internuclear ophthalmoplegia (INO; 8/17 MS, 1/17 HC, p=0.0167; vertical: 5/17 MS, 3/17 HC, p=0.6880). In HC, presence of saccadic abnormalities was not associated with age (p=0.5088).

Conclusions: VR-examination was feasible and well-tolerated by all MS and HC. Primary gaze and saccadic abnormalities were detected in a higher proportion of MS with moderate to severe disability than HC with some specific patterns such as INO not detected during routine clinical examination. VR-based oculography may serve as an outcome tool if further confirmed during our study in different MS stages.

Background: Oculomotor symptoms are frequent in Myasthenia Gravis (MG) and significantly contribute to the burden of disease in affected patients. Nevertheless, reporting of performance-dependent occurrence of double vision can often not directly be reproduced during short-term clinical examination. Here, we applied a novel AI-supported tool (PRET™)³ to objectively assess a quantitative neuroophthalmological status in patients with severe generalized MG and to demonstrate feasibility of PRET™ in neurological conditions affecting the oculomotor system.

Methods: Patients with different neurological conditions and healthy controls are currently recruited for a prospective pilot study using PRET™, a novel virtual reality (VR-) headset-based oculography tool (ethics approval no. 23-7934-BR, 15-Nov-2023, ethics committee of the Medical Faculty of Ruhr-University Bochum). Within this framework, patients with severe generalized MG have been examined clinically and using PRET™ and scored (activities of daily living MG-ADL, quality of life MG-QoL). PRET™ runs an automated programme examining gaze holding and eye movements including horizontal and vertical saccades and horizontal smooth pursuit as well as ocular alignment, fusional amplitudes, visual fields and pupillary function (the latter not evaluated, here) within less than 12 minutes. We qualitatively summarize the data of the first three patients.

Results: We present the baseline data of three MG patients prior to their first infusion of an ongoing efgartigimod treatment, all of whom reporting end-of-dose symptom worsening before reinfusion (Pat. 1: male, 63 years; Pat. 2: male, 43 years; Pat. 3: female, 21 years). All patients reported double vision of varying degrees. They fully underwent PRET™ examination without patient-sided interruption or abortion due to discomfort or motion sickness.

As compared to three healthy participants with only few, patients 1 and 2 showed several saccadic intrusions during gaze holding, yet still being able to fixate with only minor intereye horizontal gaze position difference (below 2°). Patient 3 complaining constant double vision was not able to binocularly fixate in all positions except for right-up gaze (intereye horizontal gaze position difference ranging from 5 to 10° except for right-up gaze with 0-3°).

During smooth horizontal pursuit, performed approximately 7 minutes after start of the examination, the intereye difference is higher as compared to the initial phase of the examination in all three patients hampering binocular fixation. This phenomenon of exhaustion is not seen in either of the healthy participants.

Conclusions: The automated neuroophthalmological examination was feasible in all three patients and informed objectively about performance-dependent worsening of MG-associated oculomotor symptoms during the 12-minute examination. It clearly outperformed sole clinical examination and may serve as a novel outcome tool if further confirmed during our ongoing study.