Frequency of Asymptomatic Optic Nerve Enhancement in 203 Patients With MOG Antibody-Associated Disease.

BACKGROUND AND OBJECTIVES: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a distinct CNS demyelinating disease. The rate of asymptomatic optic nerve enhancement on MRI has not been explored in patients with MOGAD. An improved understanding of this would guide clinical practice and assessment of treatment efficacy. We aimed to determine the frequency of asymptomatic optic nerve enhancement in MOGAD. METHODS: This was a retrospective review of patients evaluated at Mayo Clinic with MOGAD between January 1, 2000, and August 1, 2021 (median follow-up 1.6 [range 1-19] years). MRI studies were reviewed by masked neuroradiologists. Scans performed within 30 days of ON attack were classified as attack scans. Images obtained for routine surveillance, before ON attack, or at the time of non-ON attack were classified as interattack scans. RESULTS: Five hundred sixty-six MRIs (203 unique patients, 53% female) were included. Interattack MRIs represented 341 (60%) of the scans (median 36 days post-ON [range -1,032 to 6,001]). Of the interattack scans, 43 of 341 (13%), 30 unique patients, showed optic nerve enhancement. The enhancement was located at prior sites of ON in 35 of 43 (81%). Among the 8 patients with enhancement in new optic nerve areas, 6 had acute disseminated encephalomyelitis without an eye examination at the time of the MRI and 2 had preceding ON without imaging. Long-term visual outcomes showed no significant difference between those with and without asymptomatic enhancement, with improved visual acuity in most patients. DISCUSSION: Asymptomatic optic nerve enhancement occurred in 13% of interattack MRIs, the majority in patients with prior ON and occurring at prior sites of optic nerve enhancement. New asymptomatic optic nerve enhancement in areas without prior ON was rare. These findings are important for understanding the natural history of MOGAD, the interpretation of symptoms or response to treatment, and the adjudication of attacks in clinical trials.

Not everything is ischemic optic neuropathy.

A 71-year-old woman developed sudden, painful, decreased vision in the left eye accompanied by progressive instability. Initial examination revealed left optic disc edema, and macular optical coherence tomography confirmed the presence of intraretinal and subretinal fluid, as well as hyperreflective material under the retinal pigment epithelium. Subsequent investigations, including brain magnetic resonance imaging and a comprehensive serological analysis, ruled out infectious and autoimmune causes, further complicating the diagnostic picture. The patient's vision in both eyes continued to deteriorate, prompting empirical corticosteroid treatment. While the vision improved, the case took an unexpected turn with worsening neurological symptoms. Ultimately a brain biopsy was consistent with diffuse large B-cell lymphoma.

Denial.

A 51-year-old man presented with decreased vision, fever, confusion, headaches, agitation, nausea, vomiting and diarrhea. Magnetic resonance imaging of the brain demonstrated bilateral T2 hyperintense lesions in the region of the mesial temporal lobe and optic radiations. There was a predominantly polymorphonuclear leukocyte pleocytosis in the cerebrospinal fluid (CSF) with hyperproteinorachia. A meningoencephalitis was diagnosed. Intravenous fluorescein angiography (IVFA) demonstrated a multifocal chorioretinitis that was in a linear pattern in the left eye. CSF enzyme-linked immunosorbent assay was positive for West Nile virus (WNV) IgM. We review the clinical manifestations of WNV disease and highlight the value of IVFA in determining the diagnosis.

The potential for carbon dioxide removal by enhanced rock weathering in the tropics: An evaluation of Costa Rica.

Tropical environments show great potential to sequester CO2 by enhanced rock weathering (ERW) of powdered mafic rocks applied to agricultural fields. This study seeks to assess carbon dioxide reduction (CDR) potential in the humid tropics (1) by experimental weathering of mafic rock powders in conditions simulating humid tropical soils, and (2) from weathering rates determined from a Holocene tropical soil chronosequence where parent material is andesitic sediments. Experimentally determined weathering rates by leaching of basaltic andesites from Costa Rica (Arenal and Barva) for 50 t ha-1 applications indicate potential sequestration of 2.4 to 4.5 t CO2 ha-1 yr-1, whereas the USGS basalt standard BHVO-1 yields a rate of 11.9 t ha-1 yr-1 (influenced by more mafic composition and finer particle size). The chronosequence indicates a rate of 1.7 t CO2 ha-1 yr-1. The weathering experiment consisted of 0.6 mm of powdered rock applied atop 12 mm of Ultisol at 35 °C. To simulate a tropical soil solution, 100-mL aliquots of a dilute solution of oxalic acid in carbonated DI water were rained onto soils over a 14-day period to simulate soil moisture in the humid tropics. Solutions were collected and analyzed by ICPMS for concentrations of leached cations. A potential ERW scenario for Costa Rica was assessed assuming that one-half of lowland agricultural kaolinitic soils (mainly Ultisols, common crop and pasture soils, excluding protected areas) were to receive 50 t ha-1 of annual or biennial applications of powdered mafic rock. With an experimentally determined humid tropical CDR rate for basaltic andesite (3.5 t ha-1 yr-1) and allowances for carbon costs (e.g. emissions from processing and delivery) that reduce CDR to a net 3.2 t ha-1 yr-1, potential annual CDR of this tropical nation is ∼2-4 million tons, amounting to ∼25-50 % of annual CO2 emissions (mainly from transportation in Costa Rica).

Reexamining the Incidence of Nonarteritic Anterior Ischemic Optic Neuropathy: A Rochester Epidemiology Project Study.

BACKGROUND: This study aims to determine the population-based incidence and characterize the features of nonarteritic anterior ischemic optic neuropathy (NAION) using the Rochester Epidemiology Project (REP). METHODS: All patients diagnosed with an optic neuropathy from January 1, 1990, to December 31, 2016, were retrospectively reviewed to identify incident cases of NAION using the REP database, which is a record-linkage system of medical records for all patient-physician encounters among Olmsted County, Minnesota residents. The overall incidence of NAION was estimated using the age-specific and sex-specific population figures for Olmsted County census data for 1990 through 2016. Visual outcomes and risk factors were evaluated. The systemic risk factors were compared with age-matched controls. RESULTS: One hundred four patients were diagnosed with NAION during the 26-year study period. The overall age and sex adjusted incidence was 3.89 per 100,000 individuals (95% confidence interval [CI]: 3.14-4.65). The incidence was 7.73 (CI: 6.24-9.22) in patients aged 40 years or older and 10.19 (CI: 8.15-12.23) in patients aged 50 years or older. Median age at diagnosis was 65 years (range, 40-90 years), and 59 (56.7%) were male. The median logMAR visual acuity at presentation was 0.35 (Snellen equivalent of 20/40) with 14 patients (13.5%) having vision of counting fingers or worse. Among the 91 patients with final visual acuity outcome data available, the median visual acuity was 0.40 (Snellen equivalent of 20/50) with 12 patients (13.2%) having vision of counting fingers or worse. Twenty-four patients (26.4%) were noted to have final acuity at least 3 Snellen lines worse than at presentation, whereas 17 patients (18.7%) were noted to improve by at least 3 lines. The median mean deviation on automated visual field testing was -10.2 dB at presentation and -11.1 dB at follow-up. Twenty-two patients (21.2%) suffered NAION in the fellow eye; the median interval between involvement of the first and second eyes was 1.39 years. Systemic diseases present in the NAION cohort included hypertension (79.8%), diabetes mellitus (39.4%), obstructive sleep apnea (23.1%), and hyperlipidemia (74.0%), which were all statistically higher than age-matched controls. CONCLUSIONS: NAION is a relatively common optic neuropathy in elderly patients with vascular risk factors. Our data indicate that the incidence of NAION has remained relatively stable in the population of Olmsted County over the past 4 decades.

Ocular Neuromyotonia: Clinical Features, Diagnosis, and Outcomes.

PURPOSE: The purpose of this study was to describe the clinical features, management, outcomes, and diagnostic pitfalls in a large series of patients with ocular neuromyotonia. DESIGN: Retrospective cohort. METHODS: Patients diagnosed with ocular neuromyotonia from January 1, 2004, through January 1, 2023, seen at one of the 3 Mayo Clinic sites in Rochester, MN, Scottsdale, AZ, and Jacksonville, FL, comprised the study population. We ascertained patients with ocular neuromyotonia through a search using the medical records database. Only patients with an observed episode of ocular neuromyotonia were included and the medical records were reviewed. The main outcome measures were clinical features and outcomes of patients with ocular neuromyotonia. RESULTS: Forty-two patients who were diagnosed with ocular neuromyotonia were included. The median age was 58 years (range, 16-80 years). A history of cranial radiation therapy was present in 39 patients (93%). The sixth cranial nerve was involved in 31 patients (74%). Bilateral disease was found in 2 patients (5%). The median time from onset of diplopia to diagnosis was 8 months (range, 1 month-25 years), with a high rate of initial misdiagnosis in 52%. Twenty of 42 patients (48%) were treated with oral medication, of whom 95% had significant improvement or resolution of symptoms. CONCLUSION: Prior cranial irradiation is the most common cause for ocular neuromyotonia, affecting the sixth cranial nerve most often. Although delayed and initial misdiagnosis is common, most patients show improved symptoms on medical treatment.

A multi-centre case series of patients with coexistent intracranial hypertension and malignant arterial hypertension.

OBJECTIVE: To describe the clinical characteristics, outcomes, and management of a large cohort of patients with concomitant malignant arterial hypertension and intracranial hypertension. METHODS: Design: Retrospective case series. SUBJECTS: Patients aged ≥ 18 years with bilateral optic disc oedema (ODE), malignant arterial hypertension and intracranial hypertension at five academic institutions. Patient demographics, clinical characteristics, diagnostic studies, and management were collected. RESULTS: Nineteen patients (58% female, 63% Black) were included. Median age was 35 years; body mass index (BMI) was 30 kg/m2. Fourteen (74%) patients had pre-existing hypertension. The most common presenting symptom was blurred vision (89%). Median blood pressure (BP) was 220 mmHg systolic (IQR 199-231.5 mmHg) and 130 mmHg diastolic (IQR 116-136 mmHg) mmHg), and median lumbar puncture opening pressure was 36.5 cmH2O. All patients received treatment for arterial hypertension. Seventeen (89%) patients received medical treatment for raised intracranial pressure, while six (30%) patients underwent a surgical intervention. There was significant improvement in ODE, peripapillary retinal nerve fibre layer thickness, and visual field in the worst eye (p < 0.05). Considering the worst eye, 9 (47%) presented with acuity ≥ 20/25, while 5 (26%) presented with ≤ 20/200. Overall, 7 patients maintained ≥ 20/25 acuity or better, 6 demonstrated improvement, and 5 demonstrated worsening. CONCLUSIONS: Papilloedema and malignant arterial hypertension can occur simultaneously with potentially greater risk for severe visual loss. Clinicians should consider a workup for papilloedema among patients with significantly elevated blood pressure and bilateral optic disc oedema.

Central Retinal Artery Occlusion: Visual Outcomes from a Large Northern California Cohort.

PURPOSE: To assess visual acuity (VA) outcomes in a large cohort of patients diagnosed with nonarteritic central retinal artery occlusion (CRAO), and to ascertain whether time from symptom onset to presentation, presenting VA, or conservative treatment delivery (anterior chamber paracentesis, ocular massage, intraocular pressure lowering drugs, hyperventilation, or some combination of those) impacted ultimate VA outcomes. DESIGN: Retrospective cohort study. SUBJECTS: The study included 794 patients who presented with CRAO between 2011 and 2020. Within this cohort, 484 individuals presented within 30 days of symptom onset and had comprehensive documentation regarding the details of their presentation, management, and follow-up ≥ 90 days postdiagnosis. METHODS: Retrospective chart review was conducted for all patients with a diagnosis of CRAO initially identified via International Classification of Diseases coding, followed by confirmation of diagnosis by 2 retina specialists. Cases of arteritic CRAO were excluded. MAIN OUTCOME MEASURES: Visual acuity recovery, defined as improvement from ≤ 20/200 or worse at presentation to ≥ 20/100 ≥ 90 days after diagnosis. RESULTS: Of the 794 identified patients, 712 (89.7%) presented with VA of ≤ 20/200. Similarly, 447 (92.4%) of the 484-patient subset that presented within 30 days and had comprehensive documentation presented with VA ≤ 20/200. Of the 441 of those patients with documented follow-up, 380 (86.2%) remained at that level. Of the 244 patients who presented within 4.5 hours of symptom onset, 227 (93%) presented ≤ 20/200 and 201 (92.6%) of the 217 of those with follow-up data did not improve beyond that threshold. There was no significant difference (P < 0.05) in final VA between patients presenting before versus after 4.5 hours from time of vision loss. There was also no significant difference (P < 0.05) in VA outcomes between patients who did or did not receive conservative treatment. CONCLUSIONS: This large retrospective study further highlights the poor visual prognosis for patients with CRAO. Earlier time to presentation did not seem to impact final VA outcome, nor did conservative treatment efforts. Efficacious evidence-based treatment options are needed for this patient population. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Investigating the influence of temperature-dependent rheological properties on nanofluid behavior in heat transfer.

Nanofluids are advanced heat transfer fluids whose performance is influenced by various thermo-physical properties, including nanoparticle volume fraction, base fluid, and temperature. Rheological mathematical models have been established by using empirical data in order to characterize these features as dependent on parameters such as volume fraction, base fluid composition, and temperature. These models have been integrated into transport equations. Nanofluids composed of metallic oxides (Al2O3, SiO2) and carbon nanostructures (PEG-GnP, PEG-TGr) dispersed in deionized H2O, with nanoparticle concentrations ranging from 0.025% to 0.1%, and temperatures between 30 °C and 50 °C, were utilized to investigate flow over thin needle. The rheological models contained transport equations include the partial differential equations. The transport equations were simplified through various transformations and then solved numerically. The results in form of velocity and temperature distributions were obtained, along with boundary layer parameters, Nusselt number and coefficient of skin friction. The present study contributes to the existing knowledge by elucidating the intricate relationship between nanoparticle volume fraction, base fluid properties, and temperature in nanofluid behavior.

Optic Disc Dysplasia and Situs Inversus.

This case report discusses a diagnosis of optic disc dysplasia made on routine examination of a man aged 33 years.

Evaluating the Incidence and Neuro-Ophthalmic Manifestations of Carotid-Cavernous Fistulas.

BACKGROUND: To determine the incidence of carotid-cavernous fistula (CCF) and describe the neuro-ophthalmic manifestations and eventual clinical outcomes. METHODS: This was a population-based, retrospective cohort study using the Rochester Epidemiology Project to identify patients aged 18 years or older residing in Olmsted County, MN, diagnosed with CCF from 1997 to 2019. The medical records were reviewed for ophthalmic signs and symptoms, including conjunctival chemosis, proptosis, orbital bruit, diplopia, ophthalmoplegia, orbital pain, ocular hypertension, and blurred vision. Also determined was the number of patients with CCF found incidentally on neuroimaging, without clinical manifestations. RESULTS: Ten patients were diagnosed with a CCF between 1997 and 2019 with an overall incidence rate of 0.37 per 100,000 per year (95% CI 0.20-0.68). The median age was 50.5 years (range 23-74 years), 6 (60%) were female, and 9 were White and 1 patient was Korean. Three patients (30%) were asymptomatic and found incidentally on imaging that was obtained for unrelated reasons, and one patient's ocular details were unavailable because she passed away from severe head trauma. The following neuro-ophthalmologic or ocular manifestations were identified in the remaining 6 patients: chemosis/conjunctival injection (n = 6), cranial nerve (CN) VI palsy (n = 6), CN III palsy (n = 2), proptosis (n = 4), ocular/orbital pain (n = 3), audible orbital bruit (n = 2), ocular hypertension (n = 1), and blurred vision (n = 1). Of those patients with symptomatic CCFs, all underwent treatment except for one that spontaneously resolved. None of the patients suffered a stroke or cerebral hemorrhage. The 3 patients with incidentally discovered CCFs were asymptomatic and did not require treatment. CONCLUSIONS: This is the first population-based study to show a low incidence rate of CCFs, supporting the notion that it is an uncommon condition. Neuro-ophthalmic manifestations are common, especially chemosis/conjunctival injection and CN VI palsy. Up to a third of patients with CCF can be asymptomatic and may be found incidentally on neuroimaging during the evaluation for unrelated symptoms.

A 72-Year-Old Kidney Transplant Recipient With Visual Changes.

A 72-year-old woman with a history of kidney transplant was referred for an eye examination because of visual changes in the left eye. Both optic discs were anomalous in appearance, with central excavation in the left eye greater than the right eye. What would you do next?

Unraveling the nature of nano-diamonds and silica in a catheterized tapered artery: highlights into hydrophilic traits.

In this work, we observe the behavior of a hybrid nanofluidic model containing nanodiamonds and silica nanoparticles. The nanofluid propagates through a catheterized tapered artery with three distinct configurations: converging tapered, non-tapered and diverging tapered arteries. In order to assess the rheological properties of the blood, the third-grade non-Newtonian fluid is employed in the flow model such that the Newtonian versus non-Newtonian effects are revealed. The system of equations governing the flow is modeled under magnetic field and with heat transfer, then solved in a closed form using the perturbation approach for the pertinent parameters. The interpretations of the physical variables of interest, such as the velocity, temperature and wall shear stress, are explained. The integration of diamonds and silica nanoparticles give rise to diverse of biological applications since they are used in the drug delivery and biological imaging in genetic materials due to their hydrophilic surfaces. The present mathematical analysis lays a solid foundation on possible therapeutic applications in biomedicine.

Fluorescein Angiography Findings in Susac Syndrome: A Multicenter Retrospective Case Series.

BACKGROUND: Susac syndrome is a vasculopathy, resulting in the classic triad of branch retinal artery occlusion (BRAO), inner ear ischemia, and brain ischemia. In this retrospective chart review, we characterize fluorescein angiography (FA) findings and other ancillary studies in Susac syndrome, including the appearance of persistent disease activity and the occurrence of new subclinical disease on FA. METHODS: This multicenter, retrospective case series was institutional review board-approved and included patients with the complete triad of Susac syndrome evaluated with FA, contrasted MRI of the brain, and audiometry from 2010 to 2020. The medical records were reviewed for these ancillary tests, along with demographics, symptoms, visual acuity, visual field defects, and findings on fundoscopy. Clinical relapse was defined as any objective evidence of disease activity during the follow-up period after initial induction of clinical quiescence. The main outcome measure was the sensitivity of ancillary testing, including FA, MRI, and audiometry, to detect relapse. RESULTS: Twenty of the 31 (64%) patients had the complete triad of brain, retinal, and vestibulocochlear involvement from Susac syndrome and were included. Median age at diagnosis was 43.5 years (range 21-63), and 14 (70%) were women. Hearing loss occurred in 20 (100%), encephalopathy in 13 (65%), vertigo in 15 (75%), and headaches in 19 (95%) throughout the course of follow-up. Median visual acuity at both onset and final visit was 20/20 in both eyes. Seventeen (85%) had BRAO at baseline, and 10 (50%) experienced subsequent BRAO during follow-up. FA revealed nonspecific leakage from previous arteriolar damage in 20 (100%), including in patients who were otherwise in remission. Of the 11 episodes of disease activity in which all testing modalities were performed, visual field testing/fundoscopy was abnormal in 4 (36.4%), MRI brain in 2 (18.2%), audiogram in 8 (72.7%), and FA in 9 (81.8%). CONCLUSIONS: New leakage on FA is the most sensitive marker of active disease. Persistent leakage represents previous damage, whereas new areas of leakage suggest ongoing disease activity that requires consideration of modifying immunosuppressive therapy.

Corporate vulnerability in the US and China during COVID-19: A machine learning approach.

The impact of COVID-19 on stock market dynamics and other macroeconomic indicators has been extensively researched. However, the question of how it affects corporate vulnerability has received less attention. This article aims to fill this gap by examining the implications of COVID-19 on corporate vulnerability in the United States (US) and China, using daily data from January 2020 to December 2021. The empirical results of cointegration analysis demonstrate that COVID-19 considerably worsen corporate vulnerabilities in the long-term in the US and in the short-term in China. Additionally, non-linear results demonstrate long-run asymmetries in the US and short-run asymmetries in China, confirming the accuracy of error prediction and suggesting that US corporations are more exposed to COVID-19-induced risks. The channels through which COVID-19 may affect corporate vulnerability include changes in consumer behavior and demand, disruptions in supply chains, financial stress, government policies and regulations, and changes in the competitive landscape. This study sheds light on the effects of the COVID-19 pandemic on corporate vulnerability in the US and China, revealing regulatory implications that may necessitate greater government involvement, managerial implications that emphasize risk management and contingency planning, and social implications that highlight the importance of prioritizing stakeholder welfare and embracing digital transformation.

Population-Based Evaluation of Total Protein in Cerebrospinal Fluid.

OBJECTIVES: To present a normal range of cerebrospinal fluid (CSF) protein levels in a community-based population and to evaluate factors that contribute to CSF protein level variability. PATIENTS AND METHODS: Samples of CSF protein were obtained from participants aged 32 to 95 years who underwent lumbar puncture (LP) between November 1, 2007, and October 1, 2017, as part of the Mayo Clinic Study of Aging, a longitudinal, population-based study of residents of Olmsted County, Minnesota. RESULTS: A total of 633 participants (58.1% male; 99.1% White; mean ± SD age, 70.9±11.6 years) underwent LP with recorded CSF protein level. Mean ± SD CSF protein level was 52.2±18.4 mg/dL (to convert to mg/L, multiply by 10), with a 95% reference interval of 24.0 to 93.4 mg/dL (range, 14.0-148.0 mg/dL). Spinal stenosis and arterial hypertension were associated with higher CSF protein levels on univariable analysis (P<.001). Increasing age, male sex, and diabetes were all independently associated with higher CSF protein levels on multivariable analysis (P<.001). In the 66 participants with repeated LPs within 2.5 years, the coefficient of repeatability was 26.1 mg/dL. Eleven participants (16.7%) had a CSF protein level difference of 20 mg/dL or more between serial LPs, and 4 (6.1%) had a difference of 25 mg/dL or more. There was a trend toward greater CSF protein level variability in patients with spinal stenosis (P=.054). CONCLUSION: This large population-based study showed that CSF protein level can vary significantly among individuals. Elevated CSF protein level was independently associated with older age, male sex, and diabetes and is higher than listed in many laboratories. These findings emphasize the necessity of evidence-based reevaluation and standardization of CSF protein metrics.