Oculomotor contributions to foveal crowding.

Crowding, the phenomenon of impaired visual discrimination due to nearby objects, has been extensively studied and linked to cortical mechanisms. Traditionally, crowding has been studied extrafoveally; its underlying mechanisms in the central fovea, where acuity is highest, remain de-bated. While low-level oculomotor factors are not thought to play a role in crowding, this study shows that they are key factors in defining foveal crowding. Here we investigate the influence of fixational behavior on foveal crowding and provide a comprehensive assessment of the magnitude and extent of this phenomenon (N=13 human participants, 4 males). Leveraging on a unique blend of tools for high-precision eyetracking and retinal stabilization, we show that removing the retinal motion introduced by oculomotor behavior with retinal stabilization, diminishes the negative effects of crowding. Ultimately, these results indicate that ocular drift contributes to foveal crowding re-sulting in the same pooling region being stimulated both by the target and nearby objects over the course of time, not just in space. The temporal aspect of this phenomenon is peculiar to crowding at this scale and indicates that the mechanisms contributing to foveal and extrafoveal crowding differ.Significance Statement: Foveated stimuli are often crowded. The effects of crowding have been extensively studied in the visual periphery and are thought to have a cortical origin. Nonetheless, foveal crowding mechanisms remain elusive. Here we show that acuity drops by two lines on a Snellen Chart when flankers surround a stimulus presented at the very center of gaze. Further, at this scale, crowding cannot be regarded as a purely cortical phenomenon. Because foveal neurons' receptive fields are the smallest, eye jitter during fixation introduces spatial uncertainty by sweeping target and surrounding distractors over the same cortical pooling region even during short fixation periods, exacerbating crowding effects.

Eye drift during fixation predicts visual acuity.

Visual acuity is commonly assumed to be determined by the eye optics and spatial sampling in the retina. Unlike a camera, however, the eyes are never stationary during the acquisition of visual information; a jittery motion known as ocular drift incessantly displaces stimuli over many photoreceptors. Previous studies have shown that acuity is impaired in the absence of retinal image motion caused by eye drift. However, the relation between individual drift characteristics and acuity remains unknown. Here, we show that a) healthy emmetropes exhibit a large variability in their amount of drift and that b) these differences profoundly affect the structure of spatiotemporal signals to the retina. We further show that c) the spectral distribution of the resulting luminance modulations strongly correlates with individual visual acuity and that d) natural intertrial fluctuations in the amount of drift modulate acuity. As a consequence, in healthy emmetropes, acuity can be predicted from the motor behavior elicited by a simple fixation task, without directly measuring it. These results shed new light on how oculomotor behavior contributes to fine spatial vision.

Clinician assessment of blood alcohol levels among emergency department patients.

INTRODUCTION: Alcohol intoxication is a significant public health concern and is commonly seen among emergency department (ED) patients. This study was undertaken to identify the accuracy of clinician assessment of blood alcohol levels among emergency department patients. METHODS: This prospective survey study was conducted at a Level 1 Trauma Center. Eligible study participants included physicians, nurses, and medical students involved in the care of patients who had BAC. Clinicians estimated the BAC prior to results availability. RESULTS: Among 243 clinicians, the mean difference between the estimated BAC and actual BAC was 17.4 (95% CI: 4.7 to 30.1). Providers tended to overestimate the actual BAC level. The accuracy between roles (attendings, residents, RNs, students) was not significant (ANOVA p-value 0.90). Accuracy was not correlated with age of the patient (Pearson correlation 0.04, p-value 0.54). Accuracy was not associated with the patient's gender (Student's t-test two-tailed p-value 0.90), ethnicity (White versus all others, t-test p-value 0.31), nor insurance (government versus not government, t-test p-value 0.81). The average accuracy value was associated with mode of arrival (t-test p-value 0.003). The average accuracy for walk-in subjects was -14.9 (CI: -32.8 to 3.1) compared to ambulance arrivals 28.3 (CI: 12.7 to 44.0). Providers underestimated BAC for walk-ins and overestimated BAC for ambulance arrivals. Among 107 patients with a BAC of 0, clinician estimates ranged from 0 to 350. Clinicians estimated non-zero BAC levels in 17% of patients with BAC of 0 (N = 18). CONCLUSIONS: Clinicians' estimates of BAC were often inaccurate, and often overestimated the BAC.

Poster Session: Fixational Eye Movements in Myopia.

During fixation, an incessant drift of the eye keeps the image impinging on the retina always in motion. Previous work indicated that luminance modulations from ocular drift serve important visual functions in emmetropes (Intoy & Rucci, 2020; Clark et al 2022). However, it remains unknown how ocular drift varies under myopia, a visual impairment commonly caused by eye elongation. We measured eye movements in 19 individuals with varying degrees of myopia (-0.25D to -6.5D) using a digital Dual-Purkinje Image eye-tracker, a recently developed system with sub-arcminute resolution. Subjects observed stimuli monocularly with vision corrected via a Badal optometer. They engaged in two high-acuity tasks: (a) resolution of a 20/20 line of an eye chart (5 evenly spaced tumbling E optotypes); and (b) a more natural task where subjects were presented with images of distant faces (1°) and asked to report the image's gaze direction. We show ocular drift characteristics differ in myopes relative to emmetropes. Drift was faster and less curved in myopic observers. On the retina, these changes result in luminance modulations that amplify low spatial frequencies at the expense of high spatial frequencies, so that high-frequency signals are effectively weaker in myopes These results are consistent with the proposal that fine spatial vision strongly relies on oculomotor-induced luminance modulations and emphasize the importance of considering fine eye movements in myopia.

Poster Session: Oculomotor influences on retinal input signals in myopia.

Studies of emmetropization have traditionally focused on the spatial characteristics of visual input signals. Yet the input to the retina is not a two-dimensional pattern but a temporally-varying luminance flow. The temporal structure of this flow is predominately determined by eye movements, as the human eyes move incessantly. Even when fixating on a single point, a persistent motion known as ocular drift reformats the luminance flow in a way that counterbalances the spectra of natural scenes. It is established that emmetropes are highly sensitive to these luminance modulations. However, their visual consequences in myopia and hyperopia are unknown. Here, we first review how the temporal-frequency distribution of retinal input signals varies with the amount of ocular drift. We then use a detailed optical/geometrical model of the eye to study how the eye movements jointly shape retinal input as a function of refraction. We show that, within the temporal range of sensitivity of the retina, the spatial frequency distribution of the input signals conveys signed information about defocus. Specifically, for a given degree of defocus, myopic retinas experience more power from low spatial frequency stimuli than hyperopic retinas. These redistribution of input power may have a consequence during eye growth supporting the proposal that eye movements should be taken into consideration in the process of emmetropization.

High-resolution eye-tracking via digital imaging of Purkinje reflections.

Reliably measuring eye movements and determining where the observer looks are fundamental needs in vision science. A classical approach to achieve high-resolution oculomotor measurements is the so-called dual Purkinje image (DPI) method, a technique that relies on the relative motion of the reflections generated by two distinct surfaces in the eye, the cornea and the back of the lens. This technique has been traditionally implemented in fragile and difficult to operate analog devices, which have remained exclusive use of specialized oculomotor laboratories. Here we describe progress on the development of a digital DPI, a system that builds on recent advances in digital imaging to enable fast, highly precise eye-tracking without the complications of previous analog devices. This system integrates an optical setup with no moving components with a digital imaging module and dedicated software on a fast processing unit. Data from both artificial and human eyes demonstrate subarcminute resolution at 1 kHz. Furthermore, when coupled with previously developed gaze-contingent calibration methods, this system enables localization of the line of sight within a few arcminutes.

Comparison of Delivery of Care Before and During COVID-19 Within an Academic Outpatient Psychiatry Practice.

Introduction: The COVID-19 pandemic has challenged outpatient mental health clinics. This article compares care delivery and patient characteristics before and during the COVID-19 pandemic in outpatient mental health clinics within an academic health system. Methods: A retrospective cohort study was conducted in patients who received outpatient psychiatric services at two clinics (A and B). The investigators compared care delivery with patients with mental health conditions prepandemic (January 1-December 31, 2019) and midpandemic (January 1-December 31, 2020) periods. Care delivery was defined as the number and type of new and return visits (telehealth and face-to-face visits), patients with recorded measurement-based care (MBC) outcomes, and communication capability between patients and providers. Results: During the prepandemic period, 6,984 patients were seen in Clinics A and B, resulting in 57,629 visits. In the midpandemic period, 7,110 patients were served, resulting in 61,766 total visits. Medication management visits increased from 2019 to 2020; number of visits with documented outcome measures increased by 90% in Clinic A and 15% in Clinic B. The number of MyChart messages per patient increased more than twofold during the midpandemic period. The number of new visits with primary diagnosis of anxiety disorders increased in CY2020 and the number of visits with primary diagnosis of major depressive/mood disorders decreased in CY2020. Payor mix did not vary between the two periods although there was variability between payor mix at the two primary clinic locations. Discussion: The study suggests that there was no detrimental impact on access to care between the prepandemic and midpandemic periods within the health system. Mental health visits while pivoting to telehealth increased during the midpandemic period. Transition to telepsychiatry improved the ability to administer and document MBC.

Penetrating trauma: Relationships to recreational drug and alcohol use.

INTRODUCTION: The incidence of alcohol and recreational drug use is increasing. The impact on penetrating trauma is unknown. This study was undertaken to identify the incidence of alcohol and recreational drug use prior to penetrating trauma, and to identify ISS and outcomes among patients with penetrating trauma. METHODS: In this retrospective study, eligible subjects included trauma patients age 18 and older, with major trauma (admitted or evaluated by the Trauma Team) from 2017 to 2021. A chart review was conducted to identify data including mechanism of injury, ISS, alcohol level, toxicologic testing, length of stay, and final disposition. RESULTS: Among 1270 adult subjects with penetrating trauma during 2017 through 2020, the majority were male (N = 1071; 84%), and African American (N = 679; 54.3%) or White (N = 537; 42.9%). Mechanisms of injury included gunshot wound (GSW) (N = 973; 76.6%) or stab wound (N = 297; 23.4%). Injury severity score (ISS) ranged from 1 to 75. Among 426 subjects (33.5%) tested for recreational drugs, 395 (93%) were positive for at least one substance. The most common recreational drugs identified included marijuana (N = 280; 65.7%), benzodiazepine ((N = 131;30.8%), alcohol ((N = 248; 25.3%), opiate ((N = 116; 27.2%), cocaine (N = 87; 20.4%), and amphetamine ((N = 84; 19.7%). Subjects with an ISS of 9 to 15 had higher odds of testing positive for opiates compared to subjects with an ISS of 1 to 3 (OR 2.3). Most patients were ultimately discharged home ((N = 912;71.8%) and a minority expired (N = 142; 11.2%). CONCLUSIONS: Positive screens for alcohol and recreational drugs were common among penetrating trauma patients in this setting. The most common identified recreational drugs included marijuana, benzodiazepine, opiates, alcohol, cocaine, and amphetamine.

A case of disseminated Lyme disease in a child with skin of color.

Disseminated Lyme disease requires treatment to prevent severe sequelae, particularly neurologic. We report here a case of disseminated Lyme disease in a patient with skin of color. Pediatric dermatologists must maintain a high clinical suspicion for Lyme disease and be aware of how typical cutaneous findings may appear differently in skin of color.

Bowel-associated dermatosis-arthritis syndrome in a child with very early onset inflammatory bowel disease.

A 6-year-old boy with severe very early-onset inflammatory bowel disease (VEO-IBD) was admitted for 1 week of high fevers, loose stools, joint pains, and myalgias. He subsequently developed a progressive, papular, and vesiculopustular eruption on his face with rapid spread to his trunk and extremities. Histopathology demonstrated dense dermal neutrophilic inflammation. Findings were consistent with bowel-associated dermatosis-arthritis syndrome (BADAS), which is rarely reported in children and requires further characterization.

The role of hypothalamus-pituitary-adrenal (HPA)-like axis in inflammatory pilosebaceous disorders.

Skin is the largest peripheral endocrine organ and functions as a hormone target and endocrine gland. A cutaneous hypothalamus-pituitary-adrenal (HPA)-like axis enables the skin to respond to stress and regulates its steroidogenic activity. The pilosebaceous unit is a site for production and metabolism of a number of steroid hormones, including stress and sex hormones. This is an overview of the important role that the cutaneous HPA-like-axis plays in the pathogenesis and treatment of inflammatory pilosebaceous disorders, including acne, rosacea, seborrheic dermatitis, and hidradenitis suppurativa.

Use of 5-0 Fast Absorbing Gut versus 6-0 Fast Absorbing Gut during cutaneous wound closure on the head and neck: A randomized evaluator-blinded split-wound comparative effectiveness trial.

BACKGROUND: Absorbable suture material (Fast Absorbing Gut [FG], Ethicon, Somerville NJ) is often used for patient convenience; however, the optimal diameter of FG sutures is debatable. OBJECTIVE: To determine whether the use of 6-0 FG during repair of linear cutaneous surgery wounds on the head and neck improves scar cosmesis compared with the use of 5-0 FG. METHODS: This was a prospective, randomized, split-scar intervention in patients undergoing repair of linear cutaneous wounds on the head and neck. The scar was assessed 3 months after surgery via the Physician Observer Scar Assessment Scale (POSAS), a validated instrument. RESULTS: The difference in the sum of the POSAS component scores for 6-0 FG (12.03) compared with that for 5-0 FG (13.11) was not statistically significant (P = .26). Observer overall opinion was similar for both interventions, at 2.49 for 6-0 FG vs 2.64 for 5-0 FG (P = .54). The difference in the number of complications in the 5-0 FG group (15) vs the 6-0 FG group (10) was not statistically significant (P = .40). LIMITATIONS: Single-center study with wounds limited to the head and neck in white individuals, with a predominance of men. CONCLUSION: For linear repair of cutaneous wounds, 6-0 FG was not statistically different for cosmetic outcomes, scar width, and complications compared with 5-0 FG.

Symmetrical palatal fibromatosis: Five new cases and a review of the literature.

OBJECTIVE: To present five cases of symmetrical palatal fibromatosis (SPF), a lesion reported very rarely in the English language literature, under more than a dozen different names, and to recommend the most appropriate name. METHODS: Five SPF cases are characterized with a literature review. RESULTS: Three females and two males, aged 20-39 years, presented with bilateral, symmetrical, asymptomatic, sessile, moderately firm, or soft (n = 2) masses of the lateral posterior hard palate; two were isolated to the tuberosities. All masses were normal in color, with smooth, non-ulcerated surfaces and occasional surface nodularity. Underlying bone was radiographically normal, and adjacent teeth were asymptomatic. All masses originated from supra-periosteal tissues over palatal bone, only secondarily extending to gingivae and/or crestal tuberosity. Cases were present between 4 months and 15 years, with no familial or environmental etiologies identified. Histopathologically, masses were comprised of dense, avascular fibrous tissue with scattered thick bands of collagen. Surface epithelium showed occasional long, thin, sometimes pointed rete processes, and subepithelial stroma contained scattered large, angular fibroblasts. Conservative surgical excision appeared curative in all cases. CONCLUSIONS: The present investigators propose SPF as the most accurate name for this rare entity.

Quantification of ultraviolet (UV) radiation in the shade and in direct sunlight.

Ultraviolet (UV) radiation is associated with negative health effects, including sun damage and skin cancer. The purpose of this study is to compare the protective effects of the shade provided by a sun umbrella versus that provided by a tree. Sun sensors that register the level and dose of UV radiation were placed in the shade and in direct sunlight. Measurements were recorded every half hour between the hours of 12:30 p.m. and 3:00 p.m. in Sacramento, California. The results suggest that the level of UV radiation in the shade is not zero. The sensors located in tree shade indicated that over 5% of UV radiation was detected in the shade. The sensors located in sun-umbrella shade showed that greater than 17% of UV radiation reached the shade. The sun sensors used in our study collected UV radiation data relevant to UV index; however, they did not differentiate between UVA, UVB, visible, and infrared light. The amount of UV radiation detected in the shade is not zero, thus regular sunscreen use and other sun protective practices should be followed to reduce the risk of sun damage and skin cancer.

Utility of Routine Surveillance Imaging for Hodgkin Disease following Autologous Transplant: Experiences from a Single Institution.

BACKGROUND: Surveillance scans performed after autologous stem cell transplant (auto-HCT) for patients with Hodgkin disease (HD) have no proven survival benefit. METHODS: We studied survival differences among patients with HD after auto-HCT whose recurrences were detected on clinical history and exam, versus those detected on routine surveillance scan. RESULTS: Among the 98 patients with HD that underwent auto-HCT from 2000 to 2014 at our institution, 30 relapsed, of which 21 were detected radiologically and 9 clinically. There were no statistically significant differences in patient characteristics between the 2 groups. The median time to progression was 118 days for the clinical cohort and 284 days for the radiological cohort (p = 0.05). Median overall survival (OS) was 728 days for the clinical cohort, and was not reached for the radiological cohort (p = 0.02). DISCUSSION: In our review, most patients with HD after auto-HCT were diagnosed radiologically. Patients whose relapse was diagnosed clinically were likely to be detected earlier and have a shorter OS. Patients with aggressive disease may be detected when clinically relevant, regardless of scanning. Routine scanning may not be necessary in the majority of patients with HD following auto-HCT.

Circadian rhythm in atopic dermatitis-Pathophysiology and implications for chronotherapy.

Circadian rhythm is a biological clock that controls a wide range of physiological functions throughout the body, including various skin functions. A 24-h diurnal cycle, governed by an endogenous clock in the brain, largely controls cutaneous diurnal rhythm, which external factors, including temperature, humidity, diet, and stress, also modulate locally. Circadian rhythm influences cutaneous blood flow and properties of skin barrier function, such as transepidermal water loss and capacitance, and has important implications in atopic dermatitis (AD). This review explores how aberrations in circadian rhythm may play a role in the pathogenesis of AD and proposes implementation of chronotherapy to improve treatment outcomes in patients with AD.

Herpes zoster presenting as unilateral vasculitis.

Vasculitis can be a primary disorder or a cutaneous manifestation of a viral infection. The present case describes an atypical localized cutaneous varicella-zoster virus infection inducing a small vessel vasculitis in a patient with multisystem sarcoidosis. Additionally, we discuss the differential diagnoses and treatment options. Varicella-Zoster infection occurs more frequently in immunosuppressed populations and can present with uncharacteristic clinical manifestations complicating the diagnosis as in the present case.

Progestins and acne vulgaris: a review.

The role of exogenous progestin in the development of acne is unclear. Progestins are known for their androgenic potential, but newer generations of progestins have low or anti-androgenic activity. This review will evaluate the association between progestins found in hormonal long-acting reversible contraceptives (intrauterine devices and subdermal implants) and acne, as well as the role of oral contraceptives in acne management. Our review demonstrates that the cause and effect relationship between progestins and acne is difficult to establish and future studies that seek to understand how progestins modulate acne are necessary.

Hidradenitis Suppurativa: Disease Burden and Etiology in Skin of Color.

Hidradenitis suppurativa (HS) is a chronic, debilitating skin disease. Although most studies on HS are conducted in largely Caucasian populations, evidence demonstrates a higher prevalence in patients with skin of color, including African and Hispanic populations. These racial subgroups are likely at risk for greater disease burden due to a higher prevalence of components of the metabolic syndrome, comorbid depression, and low socioeconomic status; however, there is a paucity of research in these populations. Additionally, studies examining the genetic and anatomical basis for HS, as well as the response to HS therapies, are lacking for patients with skin of color. Complicating this issue is the limited access to effective medical care, including dermatologists, for African and Hispanic populations as well as other minority groups. In this review, we identify gaps in the knowledge base, highlight the association between HS and patients with skin of color, and provide direction for much needed research into this condition.