Representations of the relative proportions of body part width.

Despite our wealth of experience with our bodies, our perceptions of our body size are far from veridical. For example, when estimating the relative proportions of their body part lengths, using the hand as a metric, individuals tend to exhibit systematic distortions which vary across body parts. Whilst extensive research with healthy populations has focused on perceptions of body part length, less is known about perceptions of the width of individual body parts and the various components comprising these representations. Across four experiments, representations of the relative proportions of body part width were investigated for both the self and other, and when using both the hand, or a hand-sized stick as the metric. Overall, we found distortions in the perceived width of body parts; however, different patterns of distortions were observed across all experiments. Moreover, the variability across experiments appears not to be moderated by the type of metric used or individuals' posture at the time of estimation. Consequently, findings suggest that, unlike perceptions of body part length, assessed using an identical methodology, our representations of the width of the body parts measured in this task are not fixed and vary across individuals and context. We propose that, as stored width representations of these parts are not necessarily required for navigating our environments, these may not be maintained by our perceptual systems, and thus variable task performance reflects the engagement of idiosyncratic guessing strategies.

Radiation-Induced Acquired Lacrimal Drainage Obstructions: Management and Outcomes.

OBJECTIVE: To describe the management and outcomes of patients with radiation-induced acquired lacrimal duct obstructions (RALDO). METHODS: A retrospective chart review from July 2018 to December 2023 of all cases undergoing surgical intervention for RALDO by a single surgeon. Data collected included demographics, tumor type and anatomic location, radiation treatment (including radiation type, dosage, and duration), interval between radiation and reported onset of epiphora, oculoplastic clinical examination, management, and outcomes. Lacrimal irrigation was done prior to surgery in all patients. RESULTS: Seventeen eyes of 16 patients with a mean age at presentation of 63.3 years and over half the patients being females (56.3%) were included in the study. The right lacrimal drainage system (LDS) was involved in 4 (23.6%), and the left side was involved in 13 (76.4%). The mean onset of epiphora symptoms after radiation was 9.5 months. The underlying tumor type were intraocular having uveal melanoma in four, cutaneous squamous cell carcinoma in 2, basal cell carcinoma involving forehead and nose in one and sino-nasal indications present in 8 patients. One patient had metastasis to the orbit and eyelid. Four patients (25%) received external beam radiotherapy (XRT) (one case had bilateral LDS involvement), 6 patients (37.5%) received intensity-modulated radiation therapy (IMRT), 5 patients (31.25%) received proton beam irradiation (PBI), and one (6.25%) received stereotactic body radiotherapy (SBRT). Mean radiation dosage was 61.31 Gy in 15 patients (data was missing in 1 patient). Punctum was effaced in 3, canalicular stenosis in 1, proximal canalicular obstruction in 8, distal canalicular obstruction in 2, and nasolacrimal duct obstruction (NLDO) in 3. Treatment was based on the site and nature of obstruction and varied from minimally invasive techniques like serial dilatation with bicanalicular silicone tube or Guibor tube to surgical interventions like dacryocystorhinostomy (DCR) or conjunctivo-dacryocystorhinostomy (C-DCR). Only 10% with primary lacrimal intubation had good response. Of the six cases that underwent C-DCR with Jones tube either as primary or secondary procedure, four cases showed improvement in epiphora (67%). Three with NLDO did well after external DCR. In total, four patients had a secondary procedure after the first failed while 7 with failed initial surgery elected against secondary surgery. The mean follow-up was 9.6 months (range 2-24 months). CONCLUSIONS: In patients with RALDO, salvage treatment with silicone lacrimal intubation has poor results, CDCR with Jones tube has better results, although imperfect and in cases with NLDO, DCR has good outcomes.

Bilateral Dacryocystoceles in Congenital Arhinia.

Congenital arhinia is a rare anomaly characterized by a syndrome called Bosma arhinia microphthalmia syndrome. A 22-year-old woman with a history of congenital arhinia presented with bilateral discharge and enlarged bilateral lacrimal sacs, with imaging consistent with bilateral dacryocystoceles and complete absence of nasal structures. This is the first case in the literature that describes surgical management of bilateral dacryocystoceles in a patient with Bosma arhinia microphthalmia syndrome.

Deep-Learning Based Automated Segmentation and Quantitative Volumetric Analysis of Orbital Muscle and Fat for Diagnosis of Thyroid Eye Disease.

Purpose: Thyroid eye disease (TED) is characterized by proliferation of orbital tissues and complicated by compressive optic neuropathy (CON). This study aims to utilize a deep-learning (DL)-based automated segmentation model to segment orbital muscle and fat volumes on computed tomography (CT) images and provide quantitative volumetric data and a machine learning (ML)-based classifier to distinguish between TED and TED with CON. Methods: Subjects with TED who underwent clinical evaluation and orbital CT imaging were included. Patients with clinical features of CON were classified as having severe TED, and those without were classified as having mild TED. Normal subjects were used for controls. A U-Net DL-model was used for automatic segmentation of orbital muscle and fat volumes from orbital CTs, and ensemble of Random Forest Classifiers were used for volumetric analysis of muscle and fat. Results: Two hundred eighty-one subjects were included in this study. Automatic segmentation of orbital tissues was performed. Dice coefficient was recorded to be 0.902 and 0.921 for muscle and fat volumes, respectively. Muscle volumes among normal, mild, and severe TED were found to be statistically different. A classification model utilizing volume data and limited patient data had an accuracy of 0.838 and an area under the curve (AUC) of 0.929 in predicting normal, mild TED, and severe TED. Conclusions: DL-based automated segmentation of orbital images for patients with TED was found to be accurate and efficient. An ML-based classification model using volumetrics and metadata led to high diagnostic accuracy in distinguishing TED and TED with CON. By enabling rapid and precise volumetric assessment, this may be a useful tool in future clinical studies.

Molecular Design of SERTlight: A Fluorescent Serotonin Probe for Neuronal Labeling in the Brain.

The serotonergic transmitter system plays fundamental roles in the nervous system in neurotransmission, synaptic plasticity, pathological processes, and therapeutic effects of antidepressants and psychedelics, as well as in the gastrointestinal and circulatory systems. We introduce a novel small molecule fluorescent agent, termed SERTlight, that specifically labels serotonergic neuronal cell bodies, dendrites, and axonal projections as a serotonin transporter (SERT) fluorescent substrate. SERTlight was developed by an iterative molecular design process, based on an aminoethyl-quinolone system, to integrate structural elements that impart SERT substrate activity, sufficient fluorescent brightness, and a broad absence of pharmacological activity, including at serotonin (5-hydroxytryptamine, 5HT) receptors, other G protein-coupled receptors (GPCRs), ion channels, and monoamine transporters. The high labeling selectivity is not achieved by high affinity binding to SERT itself but rather by a sufficient rate of SERT-mediated transport of SERTlight, resulting in accumulation of these molecules in 5HT neurons and yielding a robust and selective optical signal in the mammalian brain. SERTlight provides a stable signal, as it is not released via exocytosis nor by reverse SERT transport induced by 5HT releasers such as MDMA. SERTlight is optically, pharmacologically, and operationally orthogonal to a wide range of genetically encoded sensors, enabling multiplexed imaging. SERTlight enables labeling of distal 5HT axonal projections and simultaneous imaging of the release of endogenous 5HT using the GRAB5HT sensor, providing a new versatile molecular tool for the study of the serotonergic system.

Recalcitrant postoperative bleeding after ectropion repair in the setting of undiagnosed chronic disseminated intravascular coagulation.

Disseminated intravascular coagulation (DIC) is characterized by abnormal activation of the coagulation cascade, which leads to simultaneous hypercoagulation and excessive bleeding. While it typically occurs in systemic diseases, such as infection, inflammation, obstetric complications, and malignancy, it can rarely manifest postoperatively. This case report describes a patient who presented with prolonged, refractory bleeding after ectropion repair via a lateral tarsal strip procedure. Due to the inability to control the patient's bleeding with conservative measures followed by surgical exploration and electrocautery, the patient underwent a hematologic work-up. Laboratory studies were consistent with DIC, attributed to his large burden of endovascular stents. He was treated with anticoagulation using apixaban in addition to tranexamic acid to achieve lasting hemostasis. This case highlights the importance of thorough preoperative assessments, even for minor surgical procedures, and systemic workup for atypical postoperative bleeding.

Periorbital necrotizing sweet syndrome: A report of two cases mimicking necrotizing soft tissue infections.

Purpose: Two cases are described of necrotizing Sweet syndrome (nSS), a rare variant of acute febrile neutrophilic dermatosis that mimics necrotizing soft tissue infections. Observation: A 74-year-old female with myelodysplastic syndrome (MDS) presented with isolated periorbital nSS that closely mimicked necrotizing fasciitis (NF); she displayed pathergy to debridement, was exquisitely responsive to corticosteroids, and underwent successful first-stage reconstruction of the eyelid with full-thickness skin grafting. A second 40-year-old female patient with relapsed acute myelogenous leukemia (AML) presented with multifocal nSS most prominently involving the eyelid. Positive herpes zoster virus (HSV) PCR and bacterial superinfection complicated the diagnosis. She improved with chemotherapy for AML and corticosteroid therapy. Conclusion: nSS is rare and a high level of clinical suspicion as well as an understanding of its distinguishing features is necessary to avoid undue morbidity. Identification of pathergy, histopathology, microbiology, and clinical context are critical to avoid misdiagnosis of infection.

Antisynthetase Syndrome Causing Necrotizing Myositis Involving Extraocular Muscles.

The authors describe the clinical, histologic, and serologic findings of a patient with necrotizing myositis of the extraocular muscles in the setting of antisynthetase syndrome, as well as subsequent management. This is the first case in the literature of a systemic necrotizing myositis to have associated ophthalmic findings.

Melanoma Arising Beneath the Lateral Rectus Muscle in a Teenager With Ocular Melanocytosis: Possible Origin From Intrascleral Melanocytes.

Ocular melanocytosis is a well-established risk factor for choroidal melanomas but, despite its reported associations in the literature, it is infrequently discussed in relation to orbital melanomas. The authors describe a teenage patient with ocular melanocytosis who presented with an asymptomatic ipsilateral right orbital mass associated with the lateral rectus muscle. An exploratory orbitotomy revealed a lesion lightly adherent to the underlying sclera. Histopathology demonstrated a markedly atypical epithelioid melanocytic proliferation, bound by a thin rim of superficial sclera, implying an origin from intrascleral melanocytes, likely within an emissary canal. Next-generation sequencing identified GNAQ and NF1 mutations. The histopathology and molecular genetics designated the lesion as having a uveal melanoma-like profile, suggesting that it may behave as a choroidal melanoma. This case underscores the importance of the association between ocular melanocytosis and orbital melanoma and provides additional evidence for primary orbital melanoma etiopathogenesis.

Jumping and leaping estimations using optic flow.

Optic flow provides information on movement direction and speed during locomotion. Changing the relationship between optic flow and walking speed via training has been shown to influence subsequent distance and hill steepness estimations. Previous research has shown that experience with slow optic flow at a given walking speed was associated with increased effort and distance overestimation in comparison to experiencing with fast optic flow at the same walking speed. Here, we investigated whether exposure to different optic flow speeds relative to gait influences perceptions of leaping and jumping ability. Participants estimated their maximum leaping and jumping ability after exposure to either fast or moderate optic flow at the same walking speed. Those calibrated to fast optic flow estimated farther leaping and jumping abilities than those calibrated to moderate optic flow. Findings suggest that recalibration between optic flow and walking speed may specify an action boundary when calibrated or scaled to actions such as leaping, and possibly, the manipulation of optic flow speed has resulted in a change in the associated anticipated effort for walking a prescribed distance, which in turn influence one's perceived action capabilities for jumping and leaping.

Microbial patterns and culture utility in orbital cellulitis.

PURPOSE: To determine the prevalence and types of pathogens found in children with orbital cellulitis and to evaluate the utility of nonoperative cultures. METHODS: This was a retrospective cohort study of children with imaging-confirmed orbital cellulitis over a period of 8 years. Outcomes included prevalence and types of organisms, polymicrobial infection, mixed aerobic-anaerobic infection, effect of age, and culture utility. RESULTS: Of 220 children with orbital cellulitis, 112 (51%) had cultures taken; 69 (31%) had surgical intervention. Culture sources for the 112 children with cultures included blood (57 patients [51%]), sinus (53 [47%]), orbit (42 [38%]), brain (6 [5%]), and skin/conjunctiva/lacrimal sac (6 [5%]). Streptococcus anginosus group strains grew in cultures from 19 children (17%); methicillin-sensitive Staphylococcus aureus (MSSA), in 15 (13%); Streptococcus pyogenes, in 12 (11%); methicillin-resistant Staphylococcus aureus (MRSA), in 6 (5%); anaerobic/facultative gram negative rods, in 8 (7%); anaerobic Gram-positive cocci, other Viridans group streptococci, and Streptococci pneumoniae, in 3 (3%) each; and normal respiratory/skin flora, in 23 (21%). Polymicrobial infection (P = 0.08) and anaerobic organisms (P = 0.58) did not differ by age (range, 0.1-16.8 years). In all 220 (100%) children, nonoperative cultures were either not obtained (108 [49%]), not helpful in avoiding surgery (69 [31%]), showed no growth (39 [18%]), or grew an organism that did not change management from empiric therapy (4 [2%]). CONCLUSIONS: While many organisms may be cultured from children with orbital cellulitis, Streptococcus and MSSA were the most common in our study cohort. MRSA is uncommon, so initial empiric coverage is not necessary. Rates of polymicrobial and anaerobic infection were similar across ages. Our results indicate that nonoperative cultures are not indicated in the initial medical management of orbital cellulitis; in our cohort, they neither resulted in treatment changes nor helped avoid surgery.

Eosinophilic Angiocentric Fibrosis of the Orbit: A Clinicopathologic Review of 6 Novel Cases With Review of the Literature.

PURPOSE: To describe 6 cases and review the current state of knowledge of eosinophilic angiocentric fibrosis (EAF) involving the orbit. DESIGN: Retrospective clinicopathologic case series and review of the current literature METHODS: Clinical records and histopathologic data of orbit-involving EAF were gathered between 2004 and 2022 from a single academic institution. The patients' presenting clinical symptoms and signs, laboratory data, radiographic studies, and management documentation were collected. RESULTS: Retrospective review identified 6 novel cases, totaling 31 cases of EAF involving the orbit described as of this writing. Fourteen patients were male, and the average age of presentation was 49.8 years (range 25-78 years). Eighteen patients had concurrent sinonasal involvement, whereas 13 had primary orbital involvement. The median duration of symptoms prior to evaluation was 24 months, with nasal symptoms, proptosis, periorbital swelling, and pain being the most common presenting symptoms. The majority of patients underwent surgical debulking, as well as treatment with glucocorticoids and steroid-sparing agents, such as rituximab, with varied results. CONCLUSION: EAF involving the orbit is uncommon. The histopathologic findings include a perivascular, eosinophil-rich infiltrate and a pauci-inflammatory storiform type of fibrosis concentrated around small vessels. Orbital involvement usually results from local extension from adjacent sinuses, but primary orbital involvement has been described. Surgical debulking and immunosuppressive agents such as rituximab have been shown to stabilize disease.

Randomized controlled pilot study assessing fructose tolerance during fructose reintroduction in non-constipated irritable bowel syndrome patients successfully treated with a low FODMAP diet.

BACKGROUND: Limited data exist to guide FODMAP (fermentable oligo-, di-, monosaccharides, and polyols) reintroduction to assess tolerance following a low FODMAP diet (LFD). Fructose reintroduction is often stepwise up to 7.5 g fructose (e.g., three tsp of honey). We aimed to determine the fructose tolerance threshold in non-constipated, LFD-responsive patients with irritable bowel syndrome (IBS) and assess whether stool microbiome predicted LFD response or fructose tolerance. METHODS: Thirty-nine non-constipated IBS patients (51% women, mean age 33.7 years) completed a 4-week LFD. LFD responders were defined as those who reported adequate relief of IBS symptoms following the LFD. Responders were randomized to one of the three solution groups (100% fructose, 56% fructose/44% glucose, or 100% glucose) and received four doses (2.5, 5, 10, 15 g) for 3 days each. Patients reached their tolerance dose if their mean daily IBS symptom severity (visual analog scale [VAS], 0-100 mm) was >20 mm higher than post-LFD VAS. Stool samples before and after LFD were analyzed using shotgun metagenomics. RESULTS: Seventy-nine percent of patients were LFD responders. Most responders tolerated the 15 g sugar dose. There was no significant difference in mean dose tolerated between solution groups (p = 0.56). Compared to baseline, microbiome composition (beta diversity) significantly shifted and six bacterial genes in fructose and mannose metabolism pathways decreased after LFD, irrespective of LFD response or the solution group. CONCLUSIONS: Non-constipated, LFD-responsive IBS patients should be reintroduced to fructose in higher doses than 15 g to assess tolerance. LFD is associated with significant changes in microbial composition and bacterial genes involved in FODMAP metabolism.

Clear Cell Syringoma of the Eyelids, a Distinctive Histopathologic Variant Associated with Diabetes Mellitus.

The authors describe the clinical and histologic findings of the clear cell variant of syringoma. Three adult female patients (age range 39-76 years old) were found to have multiple, flesh-colored lower eyelid papules, clinically consistent with syringomas, but histologically displaying abundant clear cell change. Two patients had known diagnoses of uncontrolled diabetes.

Ocular Findings in Children with Headache.

PURPOSE: To determine the prevalence of ophthalmological findings suggesting an ocular cause for headache or occult neurological disease, among children with headache. METHODS: Retrospective cross-sectional study on children with headache at a tertiary outpatient ophthalmology clinic. All children underwent sensorimotor, anterior segment, and dilated fundoscopic examinations, with or without cycloplegic refraction. Prevalence of one or more new findings of ocular or occult neurological cause of headache, including glaucoma, uveitis, optic nerve elevation, or possible asthenopia from strabismus or refractive issues. Headache characteristics and associated symptoms were evaluated as risk factors for ocular findings. RESULTS: Among 1,878 children with headache (mean age 10 yrs, range 2-18), 492 (26.1%, 95% CI 24.3-28.2%) children had one or more new ocular findings that could cause headache or indicate intracranial disease: refractive issues (342, 18.2%), strabismus (83, 4.4%), optic nerve elevation (51, 2.7%; 26 with papilledema, 25 with pseudopapilledema), uveitis (6, 0.3%), and glaucoma (2, 0.1%). Shorter headache duration was associated with ocular findings (p = .047), but headache frequency, photophobia, nausea/vomiting, and visual changes were not. In univariable analysis, visual changes (p ≤ .001), nausea/vomiting (p ≤ .002), and morning headache (p = .02) were associated with optic nerve elevation. CONCLUSION: An ophthalmologic examination including cycloplegic refraction is indicated in children with headache, as one-quarter have a treatable ocular condition, which may be related to the headache, or sign of intracranial pathology. While nausea, visual changes, or morning headache should raise concern, coincident visual, ocular, or systemic symptoms are not reliable predictors of discovering ocular pathology in a child with headache.

Dedicated Chalazion Clinic as a Tool for Early Surgical Education in Ophthalmology Residency.

Objective Ophthalmology residency programs aim to improve resident surgical teaching through increased surgical exposure over a 4-year period. Resident-centric surgical clinics across various surgical specialties have been established to help develop surgical autonomy and experience. We present the first demonstration of a resident-centric chalazion incision and drainage clinic (chalazion clinic) in an ophthalmology residency with the goal of increasing early surgical exposure to residents. Design The chalazion clinic was founded in July 2019. It is a once weekly procedure clinic conducted by an ophthalmology resident and supervised by an ophthalmology attending. Patients with chalazia were referred directly to this clinic for evaluation and management, rather than the oculoplastics clinic as they were in the past. Retrospective review of Accreditation Council for Graduate Medical Education (ACGME) case logs of all residents per academic year before and after establishment of the chalazion clinic was performed in order to assess the impact on residents' chalazion procedures numbers per academic year. Setting The study involved a single academic ophthalmology department. Participants Ophthalmology residents of all years were present. Results A resident of any year performed an average of 3.0 chalazion procedures per year in the 2018 to 2019 academic year, 3.8 in 2019 to 2020, and 8.4 in the 2020 to 2021, which represents a 180% increase in procedure numbers per resident. Among post-graduate-year 2s (PGY)2s, the average number of chalazion procedures increased from 2.1 procedure per year to 22.3 per year (961.9% increase). Conclusion To the best of our knowledge, this is the first description of a dedicated resident-centric chalazion clinic in an ophthalmology residency program. PGY2s demonstrated the largest increase in procedural numbers. While chalazion incision and drainage is a minor procedure, increased exposure to surgical procedures early in training could help improve residents' skills and confidence. This clinic provides a proof of concept of a dedicated minor procedure clinic for ophthalmology residents to increase early procedural volume.