Augmented reality (AR) displays are gaining prominence in consumer and industrial applications due to two-dimensional pupil-expanding waveguides, which achieve the essential dual requirements of compact form factors and large eyebox through innovative dual-axis beam replication technology. Nevertheless, these systems face an intrinsic trilemma compromising three critical parameters-efficiency, angular uniformity, and chromatic dispersion-with all three limitations becoming particularly pronounced at wide angles (>50°) across the visible spectrum, manifesting as fishbone artifacts (periodic non-uniformity patterns) and rainbow effects. To overcome these fundamental limitations, we present a physics-constrained generative adversarial network (PC-GAN) that systematically resolves the trilemma by incorporating two key physical principles: dilated pupil restraint ratio (DPRR) for uniformity control and periodic constraint theory (PCT) for dispersion management. This framework enables high-throughput discovery of metagrating designs while ensuring high-quality imaging performance in single-layer waveguides across the full visible spectrum and ultrawide field of view. Notably, the PC-GAN demonstrates its unique capability by autonomously discovering optimized snowflake-like metagrating (SLMG) geometries - fractal structures that provide breakthrough solutions for pupil expansion uniformity through their hierarchical light manipulation properties. Experimental realization of PC-GAN-optimized metagratings in disparate material systems (polymer and SiC) consistently delivered wide-angle, full-color operation in single-layer waveguides, while eliminating the characteristic fishbone artifacts and rainbow effects of conventional diffractive designs. This physics-constrained generative framework unlocks transformative potential for complex photonic systems beyond AR, enabling advanced designs ranging from ultrathin VR displays to multi-physics-optimized quantum optical devices.

Retinopathy of prematurity (ROP) screening is a time-sensitive, multidisciplinary clinical process that enables early detection of this vision-threatening disease while minimizing examination-related physiologic stress. This article describes a structured bedside workflow for ROP screening, including eligibility assessment, pre-examination preparation, retinal examination, differential diagnosis of uncertain findings, documentation, follow-up planning, referral, and post-examination care. Infants are selected for screening according to gestational age and birth weight criteria, with additional consideration given to clinically unstable infants considered at risk by the neonatology team. Before examination, parent communication, cardiorespiratory monitoring, pharmacologic mydriasis, and comfort measures are performed according to the screening workflow. Retinal evaluation is performed primarily by binocular indirect ophthalmoscopy combined with scleral depression, while adjunctive image documentation is obtained when available and clinically indicated. Examination findings are recorded according to the International Classification of Retinopathy of Prematurity, Third Edition (ICROP3), including zone, stage, and plus disease status, to support consistent classification and longitudinal comparison. Follow-up intervals, senior review, and referral for treatment evaluation are then assigned according to predefined decision criteria. This workflow may serve as a practical operational framework for bedside ROP screening in units seeking more uniform documentation and follow-up planning.

Brainstem arousal systems including the locus coeruleus noradrenaline system, respond transiently to behaviorally relevant events. This also drives dilations of the pupil, which are often observed during cognitive tasks. The strength of pupil responses during encoding of stimulus material predicts the success of its later retrieval, which might reflect the impact of noradrenaline on synaptic plasticity and memory formation. The pupil also dilates in response to task-irrelevant sounds, which could therefore serve as a valuable tool for investigating causal effects of phasic, pupil-linked arousal on cognition. Here, we evaluated whether task-irrelevant white noise sounds affect memory formation and memory-based decisions. These sounds were played before, during or after the presentation of memoranda (images or spoken words). Memory success was measured in recognition and free recall tasks the day after. Trial-to-trial variations in the amplitude of pupil dilations during word encoding in the absence of task-irrelevant sounds predicted memory success. Task-irrelevant white-noise sounds also robustly dilated the pupil but did not yield strong evidence of improved memory success: later recall of words was unaffected, and recall of images was weakly boosted only when the sounds were presented concurrently with them. Our results suggest that pupil-linked arousal processes triggered by task-irrelevant sounds differ from those recruited endogenously during memory formation.

The recent examination of a woman who presented a migraine attack with visual aura and unilateral mydriasis, followed, a few days later, by an episode of Takotsubo Syndrome, prompted us to review the existing literature correlating migraine and TS as well as the most recent studies regarding the association between Takotsubo Syndrome and neurological dysfunction. Our aim is to define the role of dysautonomia and the contribution of the Autonomic Nervous System in the pathogenesis of both diseases, also, to define the functional role of the hypothalamus in the both the determination of headache attacks and the onset of clinical manifestations in other organs and tissues.

Objectives: This study aims to compare the imaging performance of spectral-domain optical coherence tomography (SD-OCT) and swept-source OCT (SS-OCT) in the early postoperative assessment of patients undergoing vitreoretinal surgery with intraocular gas or air tamponade. Methods: Seventeen eyes of 17 patients who underwent pars plana vitrectomy with either sulfur hexafluoride (SF6, 20%) or air tamponade were prospectively enrolled. All patients underwent OCT imaging on postoperative day 1 using both the SD-OCT system and the SS-OCT platform, without pharmacological mydriasis. Images were independently evaluated by two experienced ophthalmologists based on the ability to delineate four prespecified anatomical layers: inner retinal layers, ellipsoid zone (EZ), retinal pigment epithelium (RPE) and choroid. Images were classified as adequate quality if two or more of these structures were identifiable. Results: SS-OCT provided adequate-quality images in all 17 eyes (100%), with complete visualization of the inner retinal layers, EZ, RPE, and choroid in 15 eyes (88.2%). In contrast, SD-OCT yielded adequate-quality images in only three of 17 eyes (17.6%), demonstrating marked signal attenuation, interface artifacts, and inability to resolve deeper retinal structures in most cases. No difference in imaging performance was observed between SF6 and air tamponade subgroups. Conclusions: SS-OCT demonstrates markedly superior imaging performance in gas-filled eyes on postoperative day 1 compared to SD-OCT, primarily attributable to its longer wavelength, reduced sensitivity roll-off, and superior penetration through optically challenging media. These findings suggest that SS-OCT may offer meaningful advantages for early postoperative monitoring following vitreoretinal surgery with tamponade; confirmation in larger prospective cohorts with clinical-outcome correlation is warranted before it can be recommended as the preferred modality.

Radiation-induced optic neuropathy is an uncommon but devastating complication of radiotherapy for head and neck tumors, characterized by subacute, painless, irreversible visual loss. Nasal mucosal melanoma, although rare, carries a high risk of visual pathway toxicity due to its proximity to anterior optic structures. We report the case of a 73-year-old woman with right nasal mucosal melanoma treated with adjuvant radiotherapy (66 Gy) and anti-PD1 immunotherapy, who developed progressive bilateral vision loss. Neuro-ophthalmological examination revealed severe visual acuity reduction, bilateral mydriasis, and optic disc pallor. Optical coherence tomography showed retinal nerve fiber layer thinning. Brain MRI demonstrated contrast enhancement of the optic chiasm and prechiasmatic optic nerves. Despite intensive treatment, the patient progressed to bilateral blindness. This case underscores the importance of early recognition of radiation-induced optic neuropathy, particularly in high-risk anatomical sites and in patients receiving radiotherapy combined with immunotherapy.

The aim of this study was to investigate pupil size as a sensitive and immediate marker of acute stress, by analyzing its evolution in response to two different stress-inducing cognitive tasks aiming to elicit distinct stress responses: a traditional Stroop task and a socially evaluative competitive Stroop task. Thirty participants were randomly assigned to either the traditional (G-trad, N = 14) or the competitive (G-comp, N = 16) Stroop groups. Stress-related measures-including pupil dilation, heart rate variability (RMSSD and SDNN), respiratory rate, blood pressure, salivary cortisol and α-amylase levels, and perceived stress (visual analog scale)-were recorded at baseline and during the 20-min recovery period. In addition, pupillary, cardiac, and respiratory responses were continuously recorded throughout the stress-inducing task, while perceived stress was assessed between task blocks. Significant increases in pupil dilation and perceived stress were observed only in G-comp during the task. Salivary cortisol increased significantly in G-comp after the Stroop, while α-amylase increased in both groups, though more markedly in G-comp. In this group, both cortisol and α-amylase exhibited a delayed peak, occurring 10 min post-task, before partially declining, reflecting a transient but intense hormonal stress response. No significant difference between the groups was found for RMSSD, SDNN, respiratory rate and blood pressure. Overall, pupil dilation was the only physiological measure recorded during task performance that differentiated between the traditional and competitive conditions. By contrast, hormonal markers exhibited delayed responses, while the other physiological measures failed to discriminate between conditions, supporting pupillometry as a non-invasive, real-time indicator of acute stress dynamics.

We report a case of traumatic choroidal rupture in a child caused by accidental injury with chopsticks at school. A healthy 12-year-old boy presented with severe right eye pain, tearing, and significant blurring of vision (6/60), right eye subconjunctival haemorrhage, corneal abrasion, traumatic mydriasis with uveitis, and posterior subcapsular rosette cataract as well as a massive submacular haemorrhage with 360 degrees of peripheral commotio retinae. Optical coherence tomography of the macula revealed areas of choroidal rupture near the optic disc and at the fovea. Conservative treatment was pursued due to the complexity of paediatric ocular surgery and the risks of intervention. Over time, visual acuity showed limited improvement to 6/36. This case highlights the diagnostic and therapeutic challenges of choroidal rupture in children, the importance of trauma prevention in children, and raises awareness on school-related injuries.

Fixed dilated pupils at the end of neurosurgical procedures are typically considered an ominous sign, often indicating acute brain injury, brainstem compression, or herniation, and are associated with poor neurological outcomes. However, pharmacological causes must also be considered. Papaverine hydrochloride, a vasodilator commonly used during intracranial surgery for the management of cerebral vasospasm, has been rarely reported to cause transient pupillary dilation and fixation. We describe the case of a 48-year-old woman with hemifacial spasm who underwent retrosigmoid craniotomy and microvascular decompression of the left facial nerve. The intraoperative course was uneventful under total intravenous anesthesia. Papaverine (200 mg) was locally infiltrated to relieve vasospasm of the anterior inferior cerebellar artery. At the conclusion of surgery, bilateral fixed dilated pupils (7 mm, nonreactive) were observed, raising concern for catastrophic intracranial pathology. Urgent neuroimaging was planned. However, within 15 minutes, the patient developed spontaneous respiratory effort, responded to commands, and her pupils returned to normal size and reactivity. She was extubated uneventfully and subsequently made a complete recovery, being discharged home on postoperative day 6. This case highlights a rare but important confounding effect of papaverine infiltration during neurosurgery. Papaverine may induce transient mydriasis mimicking signs of devastating neurological injury. Awareness of this phenomenon is critical for anesthesiologists, neurosurgeons, and critical care teams to avoid unnecessary interventions and guide appropriate postoperative decision-making.

Endobronchial ultrasound (EBUS) bronchoscopy is an indispensable tool for diagnosing lung cancer and pulmonary diseases. However, the cognitive load associated with learning and performing EBUS bronchoscopy has not been examined. This could be used to understand the critical components of performing the procedure. In this study, we attempt to characterize cognitive load using continuous pupillometry and the surgery task load index (SURG-TLX) with various experience levels to give weighted importance of various steps in EBUS bronchoscopy.

This article describes a rare case where a patient developed Adie's pupil after recovering from Bell's palsy. Adie's pupil, caused by parasympathetic involvement, presents as a dilated, poorly reactive pupil with reduced accommodation; Bell's palsy involves facial nerve dysfunction leading to facial paralysis, usually resolving within 6 months. The patient, with a prior history of fully resolved Bell's palsy, presented with right-sided Adie's pupil and absent deep tendon reflexes. Diagnosis was confirmed with 0.125% pilocarpine. While Adie's pupil has been linked to other conditions, its occurrence post-Bell's palsy is unusual, underscoring the importance of long-term follow-up in such patients.