Using an artificial intelligence software improves emergency medicine physician intracranial haemorrhage detection to radiologist levels.

BACKGROUND: Tools to increase the turnaround speed and accuracy of imaging reports could positively influence ED logistics. The Caire ICH is an artificial intelligence (AI) software developed for ED physicians to recognise intracranial haemorrhages (ICHs) on non-contrast enhanced cranial CT scans to manage the clinical care of these patients in a timelier fashion. METHODS: A dataset of 532 non-contrast cranial CT scans was reviewed by five board-certified emergency physicians (EPs) with an average of 14.8 years of practice experience. The scans were labelled in random order for the presence or absence of an ICH. If an ICH was detected, the reader further labelled all subtypes present (ie, epidural, subdural, subarachnoid, intraparenchymal and/or intraventricular haemorrhage). After a washout period, the five EPs reviewed again the scans individually with the assistance of Caire ICH. The mean accuracy of the EP readings with AI assistance was compared with the mean accuracy of three general radiologists reading the films individually. The final diagnosis (ie, ground truth) was adjudicated by a consensus of the radiologists after their individual readings. RESULTS: Mean EP reader accuracy significantly increased by 6.20% (95% CI for the difference 5.10%-7.29%; p=0.0092) when using Caire ICH to detect an ICH. Mean accuracy of the EP cohort in detecting an ICH using Caire ICH was found to be more accurate than the radiologist cohort prior to discussion; this difference, however, was not statistically significant. CONCLUSION: The Caire ICH software significantly improved the accuracy and sensitivity of detecting an ICH by the EP to a level comparable to general radiologists. Further prospective research with larger numbers will be needed to understand the impact of Caire ICH on ED logistics and patient outcomes.

Identification of successful cerebral reperfusions (mTICI ≥2b) using an artificial intelligence strategy.

BACKGROUND: The modified thrombolysis in cerebral infarction (mTICI) scale is a widely used and validated qualitative tool to evaluate angiographic intracerebral inflow following endovascular thrombectomy (EVT). We validated a machine-learning (ML) algorithm to grade digital subtraction angiograms (DSA) using the mTICI scale. MATERIALS AND METHODS: We included angiograms of identified middle cerebral artery (MCA) occlusions who underwent EVT. The complete DSA sequences were preprocessed and normalized. We created three convolutional neural networks to classify DSA into two outcomes, low- (mTICI 0,1,2a) and high-grade (mTICI 2b,2c,3). RESULTS: We included a total of 234 angiograms in this study. The area under the receiver operating characteristic was 0.863 (95% CI 0.816-0.909), 0.914 (95% CI 0.876-0.951), and 0.890 (95% CI 0.848-0.932) for the anteroposterior (AP), lateral (L), and combined models, respectively, when dichotomizing outcomes into low and high grade. The models' area under the precision-recall curve was 0.879 (95% CI 0.829-0.930), 0.906 (95% CI 0.844-0.968), and 0.887 (95% CI 0.834-0.941) for the AP, L, and combined models. CONCLUSION: In complete cerebral DSA, our angiography-based ML strategy was able to predict mTICI scores following EVT rapidly and reliably for MCA occlusions.

Bilateral medial medullary stroke: "The heart sign".

Bilateral medial medullary stroke is a very rare condition. It is usually associated with severe motor deficits, dysarthria, sensory symptoms, nystagmus, and respiratory disturbances. The most common etiology is atherosclerotic disease of the vertebral and anterior spinal artery or its branches. We present the case and brain imaging of a 48-year-old man with a bilateral medial medullary stroke and its classic "Heart Sign" in the magnetic resonance imaging. This case highlights the anatomy of the rostral medulla, clinical presentation, etiology, and characteristic radiologic findings of this uncommon type of stroke.

A deep learning method to identify and localize large-vessel occlusions from cerebral digital subtraction angiography.

BACKGROUND AND PURPOSE: An essential step during endovascular thrombectomy is identifying the occluded arterial vessel on a cerebral digital subtraction angiogram (DSA). We developed an algorithm that can detect and localize the position of occlusions in cerebral DSA. METHODS: We retrospectively collected cerebral DSAs from a single institution between 2018 and 2020 from 188 patients, 86 of whom suffered occlusions of the M1 and proximal M2 segments. We trained an ensemble of deep-learning models on fewer than 60 large-vessel occlusion (LVO)-positive patients. We evaluated the model on an independent test set and evaluated the truth of its predicted localizations using Intersection over Union and expert review. RESULTS: On an independent test set of 166 cerebral DSA frames with an LVO prevalence of 0.19, the model achieved a specificity of 0.95 (95% confidence interval [CI]: 0.90, 0.99), a precision of 0.7450 (95% CI: 0.64, 0.88), and a sensitivity of 0.76 (95% CI: 0.66, 0.91). The model correctly localized the LVO in at least one frame in 13 of the 14 LVO-positive patients in the test set. The model achieved a precision of 0.67 (95% CI: 0.52, 0.79), recall of 0.69 (95% CI: 0.46, 0.81), and a mean average precision of 0.75 (95% CI: 0.56, 0.91). CONCLUSION: This work demonstrates that a deep learning strategy using a limited dataset can generate effective representations used to identify LVOs. Generating an expanded and more complete dataset of LVOs with obstructed LVOs is likely the best way to improve the model's ability to localize LVOs.

ATP1A1-linked diseases require a malfunctioning protein product from one allele.

Heterozygous germline variants in ATP1A1, the gene encoding the α1 subunit of the Na+/K+-ATPase (NKA), have been linked to diseases including primary hyperaldosteronism and the peripheral neuropathy Charcot-Marie-Tooth disease (CMT). ATP1A1 variants that cause CMT induce loss-of-function of NKA. This heterodimeric (αß) enzyme hydrolyzes ATP to establish transmembrane electrochemical gradients of Na+ and K+ that are essential for electrical signaling and cell survival. Of the 4 catalytic subunit isoforms, α1 is ubiquitously expressed and is the predominant paralog in peripheral axons. Human population sequencing datasets indicate strong negative selection against both missense and protein-null ATP1A1 variants. To test whether haploinsufficiency generated by heterozygous protein-null alleles are sufficient to cause disease, we tested the neuromuscular characteristics of heterozygous Atp1a1+/- knockout mice and their wildtype littermates, while also evaluating if exercise increased CMT penetrance. We found that Atp1a1+/- mice were phenotypically normal up to 18 months of age. Consistent with the observations in mice, we report clinical phenotyping of a healthy adult human who lacks any clinical features of known ATP1A1-related diseases despite carrying a plasma-membrane protein-null early truncation variant, p.Y148*. Taken together, these results suggest that a malfunctioning gene product is required for disease induction by ATP1A1 variants and that if any pathology is associated with protein-null variants, they may display low penetrance or high age of onset.

External Validation of an Artificial Intelligence Device for Intracranial Hemorrhage Detection.

BACKGROUND: Artificial intelligence applications have gained traction in the field of cerebrovascular disease by assisting in the triage, classification, and prognostication of both ischemic and hemorrhagic stroke. The Caire ICH system aims to be the first device to move into the realm of assisted diagnosis for intracranial hemorrhage (ICH) and its subtypes. METHODS: A single-center retrospective dataset of 402 head noncontrast CT scans (NCCT) with an intracranial hemorrhage were retrospectively collected from January 2012 to July 2020; an additional 108 NCCT scans with no intracranial hemorrhage findings were also included. The presence of an ICH and its subtype were determined from the International Classification of Diseases-10 code associated with the scan and validated by an expert panel. We used the Caire ICH vR1 to analyze these scans, and we evaluated its performance in terms of accuracy, sensitivity, and specificity. RESULTS: We found the Caire ICH system to have an accuracy of 98.05% (95% confidence interval [CI]: 96.44%-99.06%), a sensitivity of 97.52% (95% CI: 95.50%-98.81%), and a specificity of 100% (95% CI: 96.67%-100.00%) in the detection of ICH. Experts reviewed the 10 incorrectly classified scans. CONCLUSIONS: The Caire ICH vR1 algorithm was highly accurate, sensitive, and specific in detecting the presence or absence of an ICH and its subtypes in NCCTs. This work suggests that the Caire ICH device has potential to minimize clinical errors in ICH diagnosis that could improve patient outcomes and current workflows as both a point-of-care tool for diagnostics and as a safety net for radiologists.

ATP1A1 -linked diseases require a malfunctioning protein product from one allele.

Heterozygous germline variants in ATP1A1 , the gene encoding the α1 subunit of the Na + /K + -ATPase (NKA), have been linked to diseases including primary hyperaldosteronism and the peripheral neuropathy Charcot-Marie-Tooth disease (CMT). ATP1A1 variants that cause CMT induce loss-of-function of NKA. This heterodimeric (αß) enzyme hydrolyzes ATP to establish transmembrane electrochemical gradients of Na + and K + that are essential for electrical signaling and cell survival. Of the 4 catalytic subunit isoforms, α1 is ubiquitously expressed and is the predominant paralog in peripheral axons. Human population sequencing datasets indicate strong negative selection against both missense and protein-null ATP1A1 variants. To test whether haploinsufficiency generated by heterozygous protein-null alleles are sufficient to cause disease, we tested the neuromuscular characteristics of heterozygous Atp1a1 +/- knockout mice and their wildtype littermates, while also evaluating if exercise increased CMT penetrance. We found that Atp1a1 +/- mice were phenotypically normal up to 18 months of age. Consistent with the observations in mice, we report clinical phenotyping of a healthy adult human who lacks any clinical features of known ATP1A1 -related diseases despite carrying a protein-null early truncation variant, p.Y148*. Taken together, these results suggest that a malfunctioning gene product is required for disease induction by ATP1A1 variants and that if any pathology is associated with protein-null variants, they may display low penetrance or high age of onset.

Demographic and institutional predictors of stroke hospitalization mortality among adults in the United States.

INTRODUCTION: Stroke remains a primary source of functional disability and inpatient mortality in the United States (US). Recent evidence reveals declining mortality associated with stroke hospitalizations in the US. However, data updating trends in inpatient mortality is lacking. This study aims to provide a renewed inpatient stroke mortality rate in a national sample and identify common predictors of inpatient stroke mortality. METHODS: In this cross-sectional study, we analyzed data from a nationwide database between 2010 and 2017. We included patient encounters for both ischemic (ICD9 433-434, ICD10 I630-I639) and hemorrhagic stroke (ICD9 430-432, ICD10 I600-I629). We performed an annual comparison of in-hospital stroke mortality rates, and a cross-sectional analytic approach of multiple variables identified common predictors of inpatient stroke mortality. RESULTS: Between 2010 and 2017, we identified 518,185 total stroke admissions (86.6% ischemic stroke and 13.4% hemorrhagic strokes). Stroke admissions steadily increased during the studied period, whereas we observed a steady decline in in-hospital mortality during the same time. The inpatient stroke mortality rate gradually declined from 4.8% in 2010 (95% CI 4.6-5.1) to 2.1% in 2017 (95% CI 2.0-2.1). Predictors of higher odds of dying from ischemic stroke were female (OR 1.059, 95% CI 1.015-1.105, p = 0.008), older age (OR 1.028, 95% CI 1.026-1.029, p < 0.001), and sicker patients (OR 1.091, 95% CI 1.089-1.093, p < 0.001). Predictors of higher odds of dying from hemorrhagic stroke were Hispanic ethnicity (OR 1.459, 95% CI 1.084-1.926, p < 0.001), older age (OR 1.021, 95% CI 1.019-1.023, p < 0.001), and sicker patients (OR 1.042, 95% CI 1.039-1.045, p < 0.001). All census regions and hospital types demonstrated improvements in in-hospital mortality. CONCLUSION: This study identified a continuous declining rate in in-hospital mortality due to stroke in the United States, and it also identified demographic and hospital predictors of inpatient stroke mortality.

Predicting poor response to anti-coagulation therapy in cerebral venous thrombosis using a simple clinical-radiological score.

BACKGROUND: Multiple studies have attempted to determine predictors of poor clinical outcomes in cerebral venous thrombosis (CVT). Fewer studies target to identify predictors of poor response to anticoagulation therapy in CVT. OBJECTIVE: We aimed to determine the predictors of poor clinical response to therapeutic anticoagulation in patients with acute CVT. METHODS: We performed a retrospective analysis of patients therapeutically anticoagulated for acute CVT. We defined poor clinical outcomes as death, need for mechanical thrombectomy during the hospitalization, or a modified Rankin Scale (mRS) > 3 at clinical follow-up. Bivariate and multivariate analyses identified factors associated with poor outcomes in anticoagulated patients for acute CVT, and we used the identified factors to create the PRACT-CVT (Poor Response to Anticoagulation Therapy in CVT) score. RESULTS: We included 109 patients anticoagulated with acute CVT. The mean patient age was 37 years old (SD 19); nine patients were > 65 years, ten patients were < 10 years, and 64 (59%) were female. Twenty-one (19%) patients had poor clinical outcomes. Age > 65 or < 10 years (OR: 3.16, 95% CI: 1.06-9.44), a GCS ≤ 12 upon presentation (OR: 19.2, 95% CI: 4.05-91.4), focal motor deficits at admission (OR: 5.03, 95% CI: 1.64-15.44), clinical deterioration following admission (OR: 28.18, CI: 4.81-164.86), seizures following admission (OR: 5.59, 95% CI: 1.27-24.51), evidence of brain bleeding/ischemia on admission (OR: 4.67, 95% CI: 1.42-15.34), involvement of the superior sagittal sinus (OR: 3.88, CI: 1.33-11.32), or involvement of both transverse sinuses (OR: 3.87, 95% CI: 1.01-14.90) predicted poor clinical outcome despite therapeutic anticoagulation. A PRACT-CVT score (0-22 points) of ≥ 7 points provided a sensitivity of 71% and a specificity of 95% for predicting poor clinical outcomes with anticoagulation alone. CONCLUSION: Patients with acute CVT aged > 65 or < 10 years old, presenting with a GCS ≤ 12, with focal motor deficits, showing clinical deterioration after admission, having clinical seizures during hospitalization, with brain bleeding/ischemia on initial neuroimaging, involvement of the superior sagittal sinus, or involvement of both transverse sinuses had poor response to anticoagulation. Clinicians may employ the PRACT-CVT score to predict poor response to anticoagulation for acute CVT.

Deep Learning System Boosts Radiologist Detection of Intracranial Hemorrhage.

BACKGROUND: Intracranial hemorrhage (ICH) requires emergent medical treatment for positive outcomes. While previous artificial intelligence (AI) solutions achieved rapid diagnostics, none were shown to improve the performance of radiologists in detecting ICHs. Here, we show that the Caire ICH artificial intelligence system enhances a radiologist's ICH diagnosis performance. METHODS: A dataset of non-contrast-enhanced axial cranial computed tomography (CT) scans (n=532) were labeled for the presence or absence of an ICH. If an ICH was detected, its ICH subtype was identified. After a washout period, the three radiologists reviewed the same dataset with the assistance of the Caire ICH system. Performance was measured with respect to reader agreement, accuracy, sensitivity, and specificity when compared to the ground truth, defined as reader consensus. RESULTS: Caire ICH improved the inter-reader agreement on average by 5.76% in a dataset with an ICH prevalence of 74.3%. Further, radiologists using Caire ICH detected an average of 18 more ICHs and significantly increased their accuracy by 6.15%, their sensitivity by 4.6%, and their specificity by 10.62%. The Caire ICH system also improved the radiologist's ability to accurately identify the ICH subtypes present. CONCLUSION: The Caire ICH device significantly improves the performance of a cohort of radiologists. Such a device has the potential to be a tool that can improve patient outcomes and reduce misdiagnosis of ICH.

Intravenous thrombolysis for the management of acute ischemic stroke in patients therapeutically anticoagulated with heparin: A review.

BACKGROUND: Intravenous thrombolysis (IVT) with alteplase is effective in acute ischemic stroke (AIS). However, its use rate remains low due to the many exclusion criteria. Recent guidelines recommend excluding patients suffering AIS with an elevated aPTT secondary to heparin exposure from receiving IVT. The purpose of this review is to explore the safety and efficacy of IVT in patients therapeutically anticoagulated with heparin. We also propose a treatment algorithm for IVT in patients with AIS that are therapeutically anticoagulated with heparin. METHODS: We performed a systematic review of PubMed and Embase through March 2020 to identify the literature regarding AIS in patients exposed to heparin, followed by IVT treatment, emphasizing safety, efficacy, and clinical outcome using PRISMA guidelines. RESULTS: We included thirteen articles in the final analysis, including three retrospective studies, two observational studies, one randomized trial, five case reports, and two case series. CONCLUSION: There is limited information about the off-label use of IVT in patients with elevated aPTT. Patients with AIS are excluded from IVT if they have recent exposure to heparin. Our review indicates that this population of patients may benefit from IVT as the cases of active bleeding after IVT are few, and functional outcomes are favorable in the long term suggesting that IVT in therapeutically anticoagulated patients may be safe and efficacious.

Antihypertensive use for stroke in United States emergency departments.

OBJECTIVE: Timely emergency department (ED) control of hypertension in the acute phase of stroke is associated with improved outcomes. It is unclear how emergency physicians use antihypertensive medications to treat severe hypertension associated with stroke. We sought to determine national patterns of antihypertensive use associated with ED visits for stroke in the United States. METHODS: We analyzed data from the National Hospital Ambulatory Medical Care Survey (NHAMCS) 2008-2017. We included ED visits associated with ischemic stroke (ICD9 433-434, ICD10 I630-I639) or hemorrhagic stroke (ICD9 430-432, ICD10 I600-I629). We estimated the number and proportions of stroke ED visits with triage blood pressure meeting treatment thresholds (triage systolic blood pressure [SBP] ≥180 mm Hg). We identified the frequency of antihypertensive use, as well as the most commonly used agents. RESULTS: Between 2008-2017, of a total 135,012,819 ED visits, 619,791 were associated with stroke (78.3% ischemic strokes and 21.7% hemorrhage strokes). Of all stroke visits, 21.8% received antihypertensive medications. Of the identified visits, 9.0% (95% confidence interval [CI] = 6.0%, 13.1%) ischemic stroke visits and 58.2% (95% CI = 49.0%, 66.9%) hemorrhagic stroke visits met criteria for BP reduction. A total of 47.6% (95% CI = 29.1%, 66.7%) of eligible ischemic stroke visits and 41.5% (95% CI = 30.5%, 53.3%) of eligible hemorrhagic strokes visits received antihypertensives. The most common agents used in ischemic stroke were beta-blockers, calcium-channel blockers, and ACE inhibitors. The most common agents used in hemorrhagic stroke included calcium-channel blockers, beta-blockers, and vasodilators. CONCLUSION: In this national sample, less than half of strokes presenting to the ED with hypertension received antihypertensive therapy.

Nivel de purificación del agua utilizada en clínicas odontológicas universitarias / Level of water Purification that used the Odontological Clinics University

Las aguas que se utilizan en las clínicas odontológicas deberían estar libres de contaminantes y aceites, para asegurar la calidad en los trabajos realizados. Objetivo: Determinar el contaminante en el agua del sistema de las sillas odontológicas en la UNAH-VS. Materiales y métodos: Estudio transversal, cualitativo y cuantitativo, realizado del 18 de marzo al 4 de abril 2014. Exámenes realizados con la ayuda de un laboratorio privado mediante técnicas de recolección de aguas, utilizando previamente métodos de asepsias para eliminar todo microorganismo proveniente del exterior y no del agua específicamente del grifo, mangueras y ozonificador para mayor certeza del estudio. Las muestras fueron tomadas en el lavador de la clínica grande de la facultad de odontología, ozonificador colocado arriba del mismo y silla odontológica contigua al mismo lavador. Resultados: Los exámenes demostraron que el agua del grifo contiene 47% de recuento total bacteriano y 86.13% de dureza; en el ozonificador se encontró 15% de recuento total bacteriano y 81.17% de dureza total y el agua de la silla odontológica refleja 100% en recuento total bacteriano y 83.95% de dureza total del agua. Conclusiones: El grado de contaminación del agua de las clínicas odontológicas es mayor cuando sale por las mangueras de las sillas odontológicas, la cual va directamente a la boca del paciente. El ozonificador realiza un trabajo eficiente al reducir la dureza del agua así como también el recuento bacteriano...(AU)