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Feasibility of imaging superficial palmar arch using microultrasound,7T and 3T magnetic resonance imaging

World Journal of Radiology 2017年第2期9卷 79-84页

作者： Alison N Pruzan Audrey E Kaufman Claudia Calcagno Yu Zhou zahi a fayad Venkatesh Mani Translational and Molecular Imaging Institute Department of RadiologyIcahn School of Medicine at Mount SinaiNew YorkNY 10029United States

AIM To demonstrate feasibility of vessel wall imaging of the superficial palmar arch using high frequency microultrasound, 7T and 3T magnetic resonance imaging(MRI).METHODS Four subjects(ages 22-50 years) were scanned on a micro-ultrasound system with a 45-MHz transducer(Vevo 2100, Visual Sonics). Subjects' hands were then imaged on a 3T clinical MR scanner(Siemens Biograph MMR) using an 8-channel special purpose phased array carotid coil. Lastly, subjects' hands were imaged on a 7T clinical MR scanner(Siemens Magnetom 7T Whole Body Scanner) using a custom built 8-channel transmit receive carotid coil. All three imaging modalities were subjectively analyzed for image quality and visualization of the vessel wall. RESULTS Results of this very preliminary study indicated that vessel wall imaging of the superficial palmar arch was feasible with a whole body 7T and 3T MRI in comparison with micro-ultrasound. Subjective analysis of image quality(1-5 scale, 1: poorest, 5: best) from B mode, ultrasound, 3T SPACE MRI and 7T SPACE MRI indicated that the image quality obtained at 7T was superior to both 3T MRI and micro-ultrasound. The 3D SPACE sequence at both 7T and 3T MRI with isotropic voxels allowed for multi-planarreformatting of images and allowed for less operator dependent results as compared to high frequency microultrasound imaging. Although quantitative analysis revealed that there was no significant difference between the three methods, the 7T Tesla trended to have better visibility of the vessel and its wall. CONCLUSION Imaging of smaller arteries at the 7T is feasible for evaluating atherosclerosis burden and may be of clinical relevance in multiple diseases.

关键词： Superficial Palmar Arch 7T and 3T magnetic resonance imaging Micro-ultrasound Atherosclerosis Cardiovascular disease

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Review of radiographic findings in COVID-19

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World Journal of Radiology 2020年第8期12卷 142-155页

作者： Audrey E Kaufman Sonum Naidu Sarayu Ramachandran Dalia S Kaufman zahi a fayad Venkatesh Mani Department of Radiology BioMedical Engineering and Imaging InstituteIcahn School of Medicine at Mount SinaiHess Center for Science and MedicineNew YorkNY 10029United States

The purpose of this study is to review the published literature for the range ofradiographic findings present in patients suffering from coronavirus disease 2019infection. This novel corona virus is currently the cause of a worldwide *** symptoms and signs dominate the clinical picture and radiologists arecalled upon to evaluate chest radiographs (CXR) and computed tomography (CT)images to assess for infiltrates and to define their extent, distribution andprogression. Multiple studies attempt to characterize the disease course bylooking at the timing of imaging relative to the onset of symptoms. In general,plain CXR show bilateral disease with a tendency toward the lung periphery andhave an appearance most consistent with viral pneumonia. Chest CT images aremost notable for showing bilateral and peripheral ground glass and consolidatedopacities and are marked by an absence of concomitant pulmonary nodules,cavitation, adenopathy and pleural effusions. Published literature mentioningorgan systems aside from pulmonary manifestations are relatively less common,yet present and are addressed in this review. Similarly, publications focusing onimaging modalities aside from CXR and chest CT are sparse in this evolving crisisand are likewise addressed in this review. The role of imaging is examined as it iscurrently being debated in the medical community, which is not at all surprisingconsidering the highly infectious nature of Severe Acute Respiratory Syndromecoronavirus 2.

关键词： Coronavirus COVID-19 Pneumonia Computed tomography scan X-Ray Pandemics

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Segmentation of carotid arterial walls using neural networks

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World Journal of Radiology 2020年第1期12卷 1-9页

作者： Daniel D Samber Sarayu RamachANDran Anoop Sahota Sonum Naidu Alison Pruzan zahi a fayad Venkatesh Mani Translational and Molecular Imaging Institute (TMII) Icahn School of Medicine at Mount SinaiNew York

BACKGROUND Automated,accurate,objective,and quantitative medical image segmentation has remained a challenging goal in computer science since its *** study applies the technique of convolutional neural networks(CNNs)to the task of segmenting carotid arteries to aid in the assessment of *** To investigate CNN’s utility as an ancillary tool for researchers who require accurate segmentation of carotid *** An expert reader delineated vessel wall boundaries on 4422 axial T2-weighted magnetic resonance images of bilateral carotid arteries from 189 subjects with clinically evident atherosclerotic disease.A portion of this dataset was used to train two CNNs(one to segment the vessel lumen and the other to segment the vessel wall)with the remaining portion used to test the algorithm’s efficacy by comparing CNN segmented images with those of an expert *** quantitative assessment between automated and manual segmentations was determined by computing the DICE coefficient for each pair of segmented images in the test dataset for each CNN *** average DICE coefficient for the test dataset(CNN segmentations compared to expert’s segmentations)was 0.96 for the lumen and 0.87 for the vessel *** correlation values and the intra-class correlation coefficient(ICC)were computed for the lumen(Pearson=0.98,ICC=0.98)and vessel wall(Pearson=0.88,ICC=0.86)***-Altman plots of area measurements for the CNN and expert readers indicate good agreement with a mean bias of 1%-8%.CONCLUSION Although the technique produces reasonable results that are on par with expert human assessments,our application requires human supervision and monitoring to ensure consistent *** intend to deploy this algorithm as part of a software platform to lessen researchers’workload to more quickly obtain reliable results.

关键词： Carotid arteries Segmentation Convolutional neural network Magnetic resonance imaging Vessel wall

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Effect of varying computed tomography acquisition and reconstruction parameters on semi-automated clot volume quantification

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World Journal of Radiology 2018年第3期10卷 24-29页

作者： Audrey E Kaufman Alison N Pruzan Ching Hsu Sarayu Ramachandran Adam Jacobi zahi a fayad Venkatesh Mani Department of Radiology Icahn School of Medicine at Mount SinaiNew YorkNY 10029United States Translational and Molecular Imaging Institute Icahn School of Medicine at Mount SinaiHess Center for Science and MedicineNew YorkNY 10029United States Daiichi Sankyo Inc. Basking RidgeNJ 07920United States

AIM To examine effects of computed tomography(CT)image acquisition/reconstruction parameters on clot volume quantification in vitro for research method validation *** This study was performed in conformance with HIPAA and IRB Regulations(March 2015-November 2016).A ten blood clot phantom was designed and scanned on a dual-energy CT scanner(SOMATOM Force,Siemens Healthcare Gm BH,Erlangen,Germany)with varying pitch,iterative reconstruction,energy level and slicethickness.A range of clot and tube sizes were used in an attempt to replicate in vivo emboli found within central and segmental branches of the pulmonary arteries in patients with pulmonary *** volume was the measured parameter and was analyzed by a single image analyst using a semi-automated region growing algorithm implemented in the FDA-approved Siemens *** image analysis *** model analysis was performed on the *** On the acquisition side,the continuous factor of energy showed no statistically significant effect on absolute clot volume quantification(P=0.9898).On the other hand,when considering the fixed factor of pitch,there were statistically significant differences in clot volume quantification(P<0.0001).On the reconstruction side,with the continuous factor of reconstruction slice thickness no statistically significant effect on absolute clot volume quantification was demonstrated(P=0.4500).Also on the reconstruction side,with the fixed factor of using iterative reconstructions there was also no statistically significant effect on absolute clot volume quantification(P=0.3011).In addition,there was excellent R^2 correlation between the scale-measured mass of the clots both with respect to the CT measured volumes and with respect to volumes measure by the water displacement *** Aside from varying pitch,changing CT acquisition parameters and using iterative reconstructions had no significant impact on clot volume quantification with a semi-automate

关键词： Computed tomography angiography Radiographic phantom Computer-assisted image analysis Pulmonary embolism Thrombolytic therapy

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Imaging plaque inflammation in asymptomatic cocaine addicted individuals with simultaneous positron emission tomography/magnetic resonance imaging

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World Journal of Radiology 2019年第5期11卷 62-73页

作者： Keren Bachi Venkatesh Mani Audrey E Kaufman Nadia Alie Rita Z Goldstein zahi a fayad Nelly Alia-Klein Department of Psychiatry Icahn School of Medicine at Mount SinaiOne Gustave L.Levy PlaceNew YorkNY 10029United States Department of Environmental Medicine and Public Health Icahn School of Medicine at Mount SinaiOne Gustave L.Levy PlaceNew YorkNY 10029United States Translational and Molecular Imaging Institute Icahn School of Medicine at Mount SinaiOne Gustave L.Levy PlaceNew YorkNY 10029United States Children's Hospital of Philadelphia 3401 Civic Center BlvdPhiladelphiaPA 19104United States Department of Neuroscience Icahn School of Medicine at Mount SinaiOne Gustave L.Levy PlaceNew YorkNY 10029United States

BACKGROUND Chronic cocaine use is associated with stroke, coronary artery disease and myocardial infarction, resulting in severe impairments or sudden mortality. In the absence of clear cardiovascular symptoms, individuals with cocaine use disorder (iCUD) seeking addiction treatment receive mostly psychotherapy and psychiatric pharmacotherapy, with no attention to vascular disease (i.e., atherosclerosis). Little is known about the pre-clinical signs of cardiovascular risk in iCUD and early signs of vascular disease are undetected in this underserved population. AIM To assess inflammation, plaque burden and plaque composition in iCUD aiming to detect markers of atherosclerosis and vascular disease. METHODS The bilateral carotid arteries were imaged with positron emission tomography/magnetic resonance imaging (PET/MRI) in iCUD asymptomatic for cardiovascular disease, healthy controls, and individuals with cardiovascular risk. PET with 18F-fluorodeoxyglucose (18F-FDG) evaluated vascular inflammation and 3-D dark-blood MRI assessed plaque burden including wall area and thickness. Drug use and severity of addiction were assessed with standardized instruments. RESULTS The majority of iCUD and controls had carotid FDG-PET signal greater than 1.6 but lower than 3, indicating the presence of mild to moderate inflammation. However, the MRI measure of wall structure was thicker in iCUD as compared to the controls and cardiovascular risk group, indicating greater carotid plaque burden. iCUD had larger wall area as compared to the healthy controls but not as compared to the cardiovascular risk group, indicating structural wall similarities between the non-control study groups. In iCUD, wall area correlated with greater cocaine withdrawal and craving. CONCLUSION These preliminary results show markers of carotid artery disease burden in cardiovascular disease-asymptomatic iCUD. Broader trials are warranted to develop protocols for early detection of cardiovascular risk and prevent

关键词： 3-D dark-blood magnetic resonance imaging 18F-fluorodeoxyglucose positron emission tomography Simultaneous positron emission tomography Magnetic resonance Substance use disorder Cocaine addiction Atherosclerosis Plaque burden Vascular inflammation

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Atherosclerosis imaging using 3D black blood TSE SPACE vs 2D TSE

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World Journal of Radiology 2014年第5期6卷 192-202页

作者： Stephanie K Wong Motunrayo Mobolaji-Iawal Leron Arama Joy Cambe Sylvia Biso Nadia Alie zahi a fayad Venkatesh Mani Translational and Molecular Imaging Institute Icahn School of Medicine at Mt. Sinai New York NY 10029United States Department of Radiology Icahn School of Medicine at Mt. Sinai New York NY 10029 United States Zena and Michael A Wiener Cardiovascular Institute Department of Medicine Marie-Josée and Henry R Kravis Cardiovascular Health Center Icahn School of Medicine at Mt.Sinai New York NY 10029 United States

AIM: To compare 3D Black Blood turbo spin echo(TSE)sampling perfection with application-optimized contrast using different flip angle evolution(SPACE) vs 2D TSE in evaluating atherosclerotic plaques in multiple vascular territories. METHODS: The carotid, aortic, and femoral arterial walls of 16 patients at risk for cardiovascular or atherosclerotic disease were studied using both 3D black blood magnetic resonance imaging SPACE and conventional 2D multi-contrast TSE sequences using a consolidated imaging approach in the same imaging session. Qualitative and quantitative analyses were performed on the images. Agreement of morphometric measurements between the two imaging sequences was assessed using a two-sample t-test, calculation of the intra-class correlation coefficient and by the method of linear regression and Bland-Altman analyses. RESULTS: No statistically significant qualitative differences were found between the 3D SPACE and 2D TSE techniques for images of the carotids and aorta. For images of the femoral arteries, however, there were statistically significant differences in all four qualitative scores between the two techniques. Using the current approach, 3D SPACE is suboptimal for femoral imaging. However, this may be due to coils not being optimized for femoral imaging. Quantitatively, in our study, higher mean total vessel area measurements for the 3D SPACE technique across all three vascular beds were observed. No significant differences in lumen area for both the right and left carotids were observed between the two techniques. Overall, a significant-correlation existed between measures obtained between the two approaches. CONCLUSION: Qualitative and quantitative measurements between 3D SPACE and 2D TSE techniques are comparable. 3D-SPACE may be a feasible approach in the evaluation of cardiovascular patients.

关键词： Atherosclerosis Carotid artery plaque Aorta Femoral artery Magnetic resonance imaging

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Quantification of uric acid in vasculature of patients with gout using dual-energy computed tomography

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World Journal of Radiology 2020年第8期12卷 184-194页

作者： Sharon Hannah Barazani Wei-Wei Chi Renata Pyzik Helena Chang Adam Jacobi Tom O’Donnell zahi a fayad Yousaf Ali Venkatesh Mani Department of Radiology Translational and Molecular Imaging InstituteIcahn School of Medicine at Mount SinaiNew YorkNY 10029United States Division of Rheumatology Department of MedicineIcahn School of Medicine at Mount SinaiNew YorkNY 10029United States Department of Population Health Science and Policy Icahn School of Medicine at Mount SinaiNew YorkNY 10029United States Department of Radiology Icahn School of Medicine at Mount SinaiNew YorkNY 10029United States Siemens Healthineers Erlangen 91052Germany

BACKGROUNDGout, caused by hyperuricemia and subsequent deposition of aggregatedmonosodium urate crystals (MSU) in the joints or extra-articular regions, is themost common inflammatory arthritis. There is increasing evidence that gout is anindependent risk factor for hypertension, cardiovascular disease progression *** evaluate if dual energy computed tomography (DECT) could identify MSUwithin vessel walls of gout patients, and if MSU deposits within the vasculaturediffered between patients with gout and controls. This study may help elucidatewhy individuals with gout have increased risk for cardiovascular ***31 gout patients and 18 controls underwent DECT scans of the chest andabdomen. A material decomposition algorithm was used to distinguish regions ofMSU (coded green), and calcifications (coded purple) from soft tissue (uncoded). Volume of green regions was calculated using a semi-automated volumeassessment program. Between-group differences were analyzed using Mann-Whitney U exact test and nonparametric rank *** patients had significantly higher volume of MSU within the aorta comparedto controls [Median (Min-Max) of 43.9 (0-1113.5) vs 2.9 (0-219.4), P = 0.01].Number of deposits was higher in gout patients compared to controls [Median(Min-Max) of 20 (0-739) vs 1.5 (0-104), P = 0.008]. However, the difference wasinsignificant after adjustment for age, gender, history of cardiovascular diseaseand diabetes. Increased age was positively associated with total urate volume (rs =0.64;95% confidence interval: 0.43-0.78).CONCLUSIONThis pilot study showed that DECT can quantify vascular urate deposits withvariation across groups, with gout patients possibly having higher *** relationship disappeared when adjusted for age, and there was a positiverelationship between age and MSU deposition. While this study does not provethat green coded regions are truly MSU deposition, it corroborates recent studiesthat show the pr

关键词： Gout Tophaceous Dual-energy computed tomography Hyperuricemia Monosodium urate Cardiovascular disease

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Reproducibility of thrombus volume quantification in multicenter computed tomography pulmonary angiography studies

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World Journal of Radiology 2018年第10期10卷 124-134页

作者： Audrey E Kaufman Alison N Pruzan Ching Hsu Sarayu Ramachandran Adam Jacobi Indravadan Patel Lee Schwocho Michele F Mercuri zahi a fayad Venkatesh Mani Department of Radiology Icahn School of Medicine at Mount Sinai Translational and Molecular Imaging Institute Icahn School of Medicine at Mount SinaiHess Center for Science and Medicine Daiichi Sankyo Inc. Basking Ridge

AIM To evaluate reproducibility of pulmonary embolism(PE) clot volume quantification using computed tomography pulmonary angiogram(CTPA) in a multicenter *** This study was performed using anonymized data in conformance with HIPAA and IRB Regulations(March 2015-November 2016). Anonymized CTPA data was acquired from 23 scanners from 18 imaging centers using each site's standard PE protocol. Two independent analysts measured PE volumes using a semi-automated region-growing algorithm on an FDA-approved image analysis platform. Total thrombus volume(TTV) was calculated per patient as the primary endpoint. Secondary endpoints were individual thrombus volume(ITV), Qanadli score and modified Qanadli score per patient. Inter-and intra-observer reproducibility were assessed using intra-class correlation coefficient(ICC) and BlandAltman analysis. RESULTS Analyst 1 found 72 emboli in the 23 patients with a mean number of emboli of 3.13 per patient with a range of 0-11 emboli per patient. The clot volumes ranged from 0.0041-47.34 cm3(mean +/-SD, 5.93 +/-10.15 cm3). On the second read, analyst 1 found the same number and distribution of emboli with a range of volumes for read 2 from 0.0041 – 45.52 cm3(mean +/-SD, 5.42 +/-9.53 cm3). Analyst 2 found 73 emboli in the 23 patients with a mean number of emboli of 3.17 per patient with a range of 0-11 emboli per patient. The clot volumes ranged from 0.00459-46.29 cm3(mean +/-SD, 5.91 +/-10.06 cm3). Inter-and intraobserver variability measurements indicated excellent reproducibility of the semi-automated method for quantifying PE volume burden. ICC for all endpoints was greater than 0.95 for inter-and intra-observer analysis. Bland-Altman analysis indicated no significant *** Semi-automated region growing algorithm for quantifying PE is reproducible using data from multiple scanners and is a suitable method for image analysis in multicenter clinical trials.

关键词： Pulmonary embolism Arteries Computed tomography angiography Computer-assisted image analysis Thrombolytic therapy

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心脏结节病的影像学进展

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中华核医学与分子影像杂志 2020年第2期40卷 122-128页

作者：孙若西(译) 汪蕾方纬(审校) 北京协和医学院、中国医学科学院阜外医院核医学科 100037

结节病是一种病因不明的具有非干酪样肉芽肿特征的慢性疾病。结节病的心脏受累可导致多种严重后果,如高度心脏传导阻滞、心律失常、心肌病,甚至死亡。心脏结节病可发生在已确诊结节病的患者中,也可能是疾病的唯一表现。传统的诊断技术(... 详细信息

结节病是一种病因不明的具有非干酪样肉芽肿特征的慢性疾病。结节病的心脏受累可导致多种严重后果,如高度心脏传导阻滞、心律失常、心肌病,甚至死亡。心脏结节病可发生在已确诊结节病的患者中,也可能是疾病的唯一表现。传统的诊断技术(包括超声心动图)诊断心脏结节病的灵敏度较低。越来越多的证据表明,先进心脏影像学技术(如MRI、PET)在心脏结节病的诊断、危险分层以及患者管理中具有重要价值。本综述重点强调了心脏影像学技术在评估疑似或确诊心脏结节病患者中的相关重要理论知识和实践意义。

关键词： MRI PET 心律失常心脏结节病心肌病心脏传导阻滞

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Temporal-spatial subspaces modern combination method for 2D-DOA estimation in MIMO radar

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Journal of Systems Engineering and Electronics 2017年第4期28卷 697-702页

作者： Youssef fayad Caiyun Wang Qunsheng Cao College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China College of Astronautics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A 2D-direction of arrival estimation (DOAE) for multi input and multi-output (MIMO) radar using improved multiple temporal-spatial subspaces in estimating signal parameters via rotational invariance techniques method (TS-ESPRIT) is introduced. In order to realize the improved TS-ESPRIT, the proposed algorithm divides the planar array into multiple uniform sub-planar arrays with common reference point to get a unified phase shifts measurement point for all sub-arrays. The TS-ESPRIT is applied to each sub-array separately, and in the same time with the others to realize the parallelly temporal and spatial processing, so that it reduces the non-linearity effect of model and decreases the computational time. Then, the time difference of arrival (TDOA) technique is applied to combine the multiple sub-arrays in order to form the improved TS-ESPRIT. It is found that the proposed method achieves high accuracy at a low signal to noise ratio (SNR) with low computational complexity, leading to enhancement of the estimators performance.

关键词： direction of arrival estimation (DOAE) temporal subspace spatial subspace estimating signal parameters via rotational invariance technique (ESPRIT)

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