Publications by authors named "John Eng"

Objective: In May 2009, we created a Facebook page for radiology education. While we shared a host of learning materials such as case images, quiz questions, and medical illustrations, we also posted world news, music, and memes. In February 2023, we eliminated everything from the site not related to radiology education.

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Localized interlayer excitons (LIXs) in two-dimensional moiré superlattices exhibit sharp and dense emission peaks, making them promising as highly tunable single-photon sources. However, the fundamental nature of these LIXs is still elusive. Here, we show the donor-acceptor pair (DAP) mechanism as one of the origins of these excitonic peaks.

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The omnipresence of hexagonal boron nitride (hBN) in devices embedding two-dimensional materials has prompted it as the most sought after platform to implement quantum sensing due to its testing while operating capability. The negatively charged boron vacancy () in hBN plays a prominent role, as it can be easily generated while its spin population can be initialized and read out by optical means at room-temperature. But the lower quantum yield hinders its widespread use as an integrated quantum sensor.

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The ideal single-photon source displaying high brightness and purity, emission on-demand, mature integration, practical communication wavelength (i.e., in the telecom range), and operating at room temperature does not exist yet.

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Rationale And Objectives: We post several times daily on our Facebook page, CTisus, to educate radiology students and professionals globally. We aimed to determine how our data compared for different types of posts and ascertain the popularity of videos versus case images, illustrations versus case images, and whether cinematic rendering performed better than traditional computed tomography.

Materials And Methods: We exported data for one year's worth of Facebook posts (November 1, 2020 to October 31, 2021) and categorized posts into 18 types.

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Background Longitudinal data on the association of quantitative thigh muscle MRI markers with knee osteoarthritis (KOA) outcomes are scarce. These associations are of clinical importance, with potential use for thigh muscle-directed disease-modifying interventions. Purpose To measure KOA-associated longitudinal changes in MRI-derived muscle cross-sectional area (CSA) and adipose tissue and their association with downstream symptom worsening and knee replacement (KR).

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Purpose: To assess generalizability of published deep learning (DL) algorithms for radiologic diagnosis.

Materials And Methods: In this systematic review, the PubMed database was searched for peer-reviewed studies of DL algorithms for image-based radiologic diagnosis that included external validation, published from January 1, 2015, through April 1, 2021. Studies using nonimaging features or incorporating non-DL methods for feature extraction or classification were excluded.

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Rationale And Objectives: There are several popular radiology channels on YouTube, reinforcing studies showing interest among medical students and trainees in video education and suggesting the potential use of YouTube for radiology education.

Materials And Methods: The CTisus YouTube channel, dedicated to radiology education and based in the Russell H. Morgan Department of Radiology and Radiological Science at Johns Hopkins Hospital, has 25,000 subscribers.

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Machine learning (ML) algorithms have demonstrated high diagnostic accuracy in identifying and categorizing disease on radiologic images. Despite the results of initial research studies that report ML algorithm diagnostic accuracy similar to or exceeding that of radiologists, the results are less impressive when the algorithms are installed at new hospitals and are presented with new images. This phenomenon is potentially the result of selection bias in the data that were used to develop the ML algorithm.

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Purpose: To (1) develop a deep learning system (DLS) using a deep convolutional neural network (DCNN) for identification of pneumothorax, (2) compare its performance to first-year radiology residents, and (3) evaluate the ability of a DLS to augment radiology residents by detecting missed pneumothoraces.

Methods: This was a retrospective study performed in September 2018. We obtained 112,120 chest radiographs (CXRs) from the NIH ChestXray14 database, of which 4360 cases (4%) were labeled as pneumothorax by natural language processing.

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Background The overall rate of hip fractures not identified on radiographs but that require surgery (ie, surgical hip fractures) remains unclear in elderly patients who are suspected to have such fractures based on clinical findings. Moreover, the importance of advanced imaging in these patients has not been comprehensively assessed. Purpose To estimate the frequency of radiographically occult hip fracture in elderly patients, to define the higher-risk subpopulation, and to determine the diagnostic performance of CT and bone scanning in the detection of occult fractures by using MRI as the reference standard.

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Since its 2010 launch, Instagram has rapidly risen to become one of the leading social media in the world, with more than one billion monthly users. Within the field of radiology, perhaps because of the image-weighted nature of the platform, several prominent organizations host Instagram accounts, including the Radiological Society of North America, American Roentgen Ray Society, American College of Radiology, and the American Board of Radiology. We started our own Instagram account in January 2016 because of the popularity of this social media platform among medical students.

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Background Few data exist on the long-term risk prediction of elevated left ventricular (LV) mass quantified by MRI for cardiovascular (CV) events in a contemporary, ethnically diverse cohort. Purpose To assess the long-term impact of elevated LV mass on CV events in a prospective cohort study of a multiethnic population in relationship to risk factors and coronary artery calcium (CAC) score. Materials and Methods The Multi-Ethnic Study of Atherosclerosis, or MESA (: NCT00005487), is an ongoing prospective multicenter population-based study in the United States.

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Objectives: To evaluate the added value of diffusion-weighted imaging (DWI) on MRI in differentiating serous from mucin-producing pancreatic cystic neoplasms (PCNs).

Methods: One hundred seventeen patients with PCN measuring ≥ 10 mm were included. Three readers independently evaluated MRI with and without the use of apparent diffusion coefficient (ADC).

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Purpose To investigate the diagnostic performance of three-dimensional (3D) MRI for depicting meniscal injuries of the knee by using surgery as the standard of reference. Materials and Methods A literature search was performed to identify original studies published between 1985 and 2017. Summary receiver operating characteristic curve and sensitivity analyses were performed to compare the diagnostic performance of 3D versus two-dimensional (2D) MRI for the assessment of knee meniscal injuries and to evaluate the impact of relevant covariates on the diagnostic performance for assessment of knee meniscal injuries.

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Purpose To compare epicardial fat in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) with that in healthy subjects. Materials and Methods In this retrospective study, cardiac CT scans in 44 patients with ARVD/C (mean age, 39 years ± 12; 23 men) were compared with those in 45 control group participants between January 2008 and July 2015. Volumes of intrathoracic adipose tissue, mediastinal adipose tissue (MAT), and total epicardial adipose tissue (EAT) were quantified.

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Purpose To determine the diagnostic performance of three-dimensional (3D) MRI for the depiction and characterization of cartilage defects within the knee joint by using arthroscopy and/or open surgery as the standard of reference. Materials and Methods A systematic literature search was performed to extract diagnostic studies published between January 1985 and October 2017. Two independent investigators assessed the methodologic quality of each study by using Quality Assessment of Diagnostic Accuracy Studies 2.

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Objective: The purpose of this study is to determine the diagnostic performance of MRI and MR arthrography for depicting ligamentum teres lesions.

Materials And Methods: A literature search was performed. Original studies reporting the diagnostic accuracy of MRI examinations for the depiction of ligamentum teres lesions were included.

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Bolus timing is critical to optimal magnetic resonance angiography (MRA) acquisitions but can be challenging in some patients. Our purpose was to evaluate whether contrast-enhanced time-resolved magnetic resonance angiography (TR-MRA), a dynamic multiphase sequence that does not rely on bolus timing, is a viable alternative method to conventional 3D fast-long angle shot contrast-enhanced magnetic resonance angiography (CE-MRA). Coronal subtracted conventional CE-MRA images in 50 consecutive patients presenting for pre-atrial fibrillation ablation pulmonary venous (PV) mapping were compared with 50 TR-MRA images performed in 50 subsequent patients.

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The purpose of this study was to determine the diagnostic accuracy of an iPhone for evaluation of the coronary arteries on coronary CT angiography (CTA) in comparison to a standard clinical workstation. Fifty coronary CTA exams were selected to include a range of normal and abnormal cases including both coronary artery disease (CAD) of varying severity and coronary artery anomalies. Two cardiac radiologists reviewed each exam on a standard clinical workstation initially and then on an iPhone 6 after a washout period.

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Background: Few adults have ideal cardiovascular health (CVH). We studied associations of an overall CVH score with subclinical cardiovascular disease and events. We assessed whether associations varied by race/ethnicity.

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Rationale And Objectives: The study aimed to perform a systematic review and meta-analysis for evaluating the diagnostic accuracy of 1.5 Tesla and 3.0 Tesla magnetic resonance imaging (MRI), and magnetic resonance arthrography (MRA), in the detection of scapholunate interosseous ligament (SLIL) injury.

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The feasibility of remote reading of coronary CT examinations on tablet computers has not been evaluated. The purpose of this study is to evaluate the accuracy of coronary CT angiography reading using an iPad compared to standard 3D workstations. Fifty coronary CT angiography exams, including a spectrum of coronary artery disease and anatomic variants, were reviewed.

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