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Advantage in Bright-blood and Black-blood magnetic resonance Imaging with High-resolution for Analysis of Carotid Atherosclerotic Plaques

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Chinese Medical Journal 2015年第18期128卷 2478-2484页

作者： Mei Li Wei-Jie Le Xiao-Feng Tao Ming-Hua Li Yue-Hua Li Nan Qu Department of Radiology Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University Shanghai 200233 China Department of Radiology Shanghai Ninth People's Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200011 China

Background： About 50% of the cerebral ischemia events are induced by intracranial and extracranial atheroscterosis. This study aimed to evaluate the feasibility and accuracy for displaying atherosclerotic plaques in carotid arteries and analyzing their ingredients by using high-resolution new magnetic resonance imaging （MRI） techniques. Methods： Totally, 49 patients suspected ofextracranial carotid artery stenosis were subjected to cranial MRI scan and magnetic resonance angiography （MRA） examination on carotid arteries, and high-resolution bright-blood and black-blood MRI analysis was carried out within 1 week. Digital subtraction angiography （DSA） examination was carried out for 16 patients within I month. Results： Totally, 103 plaques were detected in the 49 patients, which were characterized by localized or diffusive thickening of the vessel wall, with the intrusion of crescent-shaped abnormal signal into lumens. Fibrous cap was displayed as isointensity in T I -weighted image （T I WI） and hyperintensities in proton density weighted image （PDWI） and T2-weighted image （T2WI）, lipid core was displayed as isointensity or slight hyperintensities in T1WI, isointensity, hyperintensities or hypointensity in PDWI, and hypointensity in T2WI. Calcification in plaques was detected in 11 patients. Eight patients were detected with irregular plaque surface or ulcerative plaques, which were characterized by irregular intravascular space surface in the black-blood sequences, black hypointensity band was not detected in three-dimensional time-of-flight, or the hypointensity band was not continuous, and intrusion of hyperintensities into plaques can be detected. Bright-blood and black-blood techniques were highly correlated with the diagnosis of contrast-enhanced MRA in angiostenosis degree, Rs 0.97, P 〈 0.001. In comparison to DSA, the sensitivity, specificity, and accuracy of MRI diagnosis of stenosis for ≥50% were 88.9%. 100%, and 97.9%, respectively. Conclusions： High-resolu

关键词： Atherosclcrosis Black-blood Bright-blood Carotid Arteries magnetic resonance image

Unstructured Oncological image Cluster Identification Using Improved Unsupervised Clustering Techniques

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Computers, Materials & Continua 2022年第7期72卷 281-299页

作者： S.Sreedhar Kumar Syed Thouheed Ahmed Qin Xin S.Sandeep M.Madheswaran Syed Muzamil Basha Dr.T.Thimmaiah Institute of Technology VTUKGFKarnatakaIndia School of Computing&Information Technology REVA UniversityBengaluruIndia Faculty of Science and Technology University of the Faroe IslandsFaroe IslandsDenmark K S School of Engineering BengaluruIndia Muthayammal Engineering College RasipuramTamil NaduIndia

This paper presents,a new approach of Medical image Pixels Clustering(MIPC),aims to trace the dissimilar patterns over the magnetic resonance(MR)image through the process of automatically identify the appropriate number of distinct clusters based on different improved unsupervised clustering schemes for enrichment,pattern predication and deeper *** proposed MIPC consists of two stages:clustering and *** the clustering stage,the MIPC automatically identifies the distinct number of dissimilar clusters over the gray scale MR image based on three different improved unsupervised clustering schemes likely improved Limited Agglomerative Clustering(iLIAC),Dynamic Automatic Agglomerative Clustering(DAAC)and Optimum N-Means(ONM).In the second stage,the performance of MIPC approach is estimated by measuring Intra intimacy and Intra contrast of each individual cluster in the result of MR image based on proposed validation method namely Shreekum Intra Cluster Measure(SICM).Experimental results showthat the MIPC approach is better suited for automatic identification of highly relative dissimilar clusters over the MR cancer images with higher Intra closeness and lower Intra contrast based on improved unsupervised clustering schemes.

关键词： magnetic resonance image unsupervised clustering scheme intra intimacy intra contrast iLIAC shreekum intra cluster measure medical image clustering

Enhanced Feature Fusion Segmentation for Tumor Detection Using Intelligent Techniques

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Intelligent Automation & Soft Computing 2023年第3期35卷 3113-3127页

作者： R.Radha R.Gopalakrishnan Department of Information and Communication Engineering Anna UniversityChennai600025TamilnaduIndia Department of Electrical and Electronics Engineering K.S.Rangasamy College of TechnologyTiruchengode637215TamilnaduIndia

In theﬁeld of diagnosis of medical images the challenge lies in tracking and identifying the defective cells and the extent of the defective region within the complex structure of a brain *** the defective cells precisely during the diagnosis phase helps toﬁght the greatest exterminator of *** detec-tion of these defective cells requires an accurate computer-aided diagnostic system(CAD)that supports early treatment and promotes survival rates of *** ear-lier version of CAD systems relies greatly on the expertise of radiologist and it con-sumed more time to identify the defective *** manuscript takes the efﬁcacy of coalescing features like intensity,shape,and texture of the magnetic resonance image(MRI).In the Enhanced Feature Fusion Segmentation based classiﬁcation method(EEFS)the image is enhanced and segmented to extract the prominent *** bring out the desired effect the EEFS method uses Enhanced Local Binary Pattern(EnLBP),Partisan Gray Level Co-occurrence Matrix Histogram of Oriented Gradients(PGLCMHOG),and iGrab cut method to segment *** prominent features along with deep features are coalesced to provide a single-dimensional fea-ture vector that is effectively used for *** coalesced vector is used with the existing classiﬁers to compare the results of these classiﬁers with that of the gen-erated *** generated vector provides promising results with commendably less computatio nal time for pre-processing and classiﬁcation of MR medical images.

关键词： Enhanced local binary pattern level iGrab cut method magnetic resonance image computer aided diagnostic system enhanced feature fusion segmentation enhanced local binary pattern

A more consistent intraluminal rhesus monkey model of ischemic stroke

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Neural Regeneration Research 2014年第23期9卷 2087-2094页

作者： Bo Zhao Guowei Shang Jian Chen Xiaokun Geng Xin Ye Guoxun Xu Ju Wang Jiasheng Zheng Hongjun Li Fauzia Akbary Shengli Li Jing Lu Feng Ling Xunming Ji Department of Neurosurgery Xuanwu Hospital Capital Medical University Department of Anesthesiology Xuanwu Hospital Capital Medical University Department of Laboratory Animal Science Capital Medical University Radiology Department Beijing Youan Hospital Capital Medical University Wayne State University School of Medicine Center of Stroke Beijing Institute for Brain Disorders

Endovascular surgery is advantageous in experimentally induced ischemic stroke because it causes fewer cranial traumatic lesions than invasive surgery and can closely mimic the pathophysiology in stroke patients. However, the outcomes are highly variable, which limits the accuracy of evaluations of ischemic stroke studies. In this study, eight healthy adult rhesus monkeys were randomized into two groups with four monkeys in each group： middle cerebral artery occlusion at origin segment （M1） and middle cerebral artery occlusion at M2 segment. The blood flow in the middle cerebral artery was blocked completely for 2 hours using the endovascular microcoil placement technique （1 mm × 10 cm）（undetachable）, to establish a model of cerebral ischemia. The microcoil was withdrawn and the middle cerebral artery blood flow was restored. A reversible middle cerebral artery occlusion model was identified by hematoxylin-eosin staining, digital subtraction angiography, magnetic resonance angiography, magnetic resonance imaging, and neurological evaluation. The results showed that the middle cerebral artery occlusion model was successfully established in eight adult healthy rhesus monkeys, and ischemic lesions were apparent in the brain tissue of rhesus monkeys at 24 hours after occlusion. The rhesus monkeys had symptoms of neurological deficits. Compared with the M1 occlusion group, the M2 occlusion group had lower infarction volume and higher neurological scores. These experimental findings indicate that reversible middle cerebral artery occlusion can be produced with the endovascular microcoil technique in rhesus monkeys. The M2 occluded model had less infarction and less neurological impairment, which offers the potential for application in the field of brain injury research.

关键词： nerve regeneration brain injury rhesus monkeys model middle cerebral artery microcoil infarction stroke interventional therapy digital subtraction angiography magnetic resonance image neuroimaging neuroregeneration

visual bone marrow mesenchymal stem cell transplantation in the repair of spinal cord injury

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Neural Regeneration Research 2015年第3期10卷 404-411页

作者： Rui-ping Zhang Cheng Xu Yin Liu Jian-ding Li Jun Xie Department of Radiology First HospitalShanxi Medical University Molecular Imaging Program at Stanford Stanford University Department of Radiology Shanxi Provincial People’s Hospital Department of Molecular Biology Shanxi Medical University

An important factor in improving functional recovery from spinal cord injury using stem cells is maximizing the number of transplanted cells at the lesion site. Here, we established a contusion model of spinal cord injury by dropping a weight onto the spinal cord at T7_8. Superparamagnet- ic iron oxide-labeled bone marrow mesenchymal stem cells were transplanted into the injured spinal cord via the subarachnoid space. An outer magnetic field was used to successfully guide the labeled cells to the lesion site. Prussian blue staining showed that more bone marrow mesen- chymal stem cells reached the lesion site in these rats than in those without magnetic guidance or snperparamagnetic iron oxide labeling, and immunofluorescence revealed a greater number of complete axons at the lesion site. Moreover, the Basso, Beattie and Bresnahan （BBB） locomotor rating scale scores were the highest in rats with superparamagnetic labeling and magnetic guid- ance. Our data confirm that superparamagnetic iron oxide nanoparticles effectively label bone marrow mesenchymal stem cells and impart sufficient magnetism to respond to the external magnetic field guides. More importantly, superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells can be dynamically and non-invasively tracked in vivo using magnetic resonance imaging. Superparamagnetic iron oxide labeling of bone marrow mesenchymal stem cells coupled with magnetic guidance offers a promising avenue for the clinical treatment of spinal cord injury.

关键词： nerve regeneration superparamagnetic iron oxide magnetic guidance bone marrowmesenchymal stem cells spinal cord injury cell transplantation magnetic resonance image lumbarpuncture neural regeneration

Zwitterionic Manganes Metal-Organic Frameworks as Potential magnetic resonance Contrast Agents

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Zwitterionic Manganes Metal-Organic Frameworks as Potential ...

Triple-modal imaging of stem-cells labeled with multimodal nanoparticles, applied in a stroke model

第十届全国化学生物学学术会议

作者： Ke-Yang Wu Liang Qin Pei-Pei Hu Bin Sun Bao-Ping Xie Jin-Xiang Chen Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical SciencesSouthern Medical University

magnetic resonance imaging(MRI) is a powerful non-invasive medical diagnostic technique.1 It can differentiate abnormalities from normal tissues based on their varied NMR water proton signals. Because Gd has high electron spin(S = 7/2) and low electronic relaxation, some Gd-based compounds have been clinically used as MRI positive contrast agents. However, further use of MRI agents of Gd based compounds as adequate MRI contrast agents is restricted due to their moderate longitudinal(r1) relaxation rates and large administration dose,3 which will lead to severe kidney failure. Herein, we have synthesized three water-stable and soluble Mn(II)-based metal organic frameworks(MOFs) 1-3 from three types of zwitterionic carboxylates. These three MOFs show different two or one dimensional structure respectively(Fig. 1). They all showed good r1 relaxivities and T1-weighted images and very low cytotoxicity toward human embryonic kidney cell line(HEK 293). After intravenous administration of 1, kidneys and liver of Kunming mice showed remarkably positive signal enhancement after 5 min compared with the pre-injection images. The hyperintensity of kidneys and liver persisted about 60 min and then decreased. The structures of organs from the exposed mice were similar to those of the control group. MOF 1 have high potential as an MRI contrast agent for potential clinical use in displaying the anatomy and pathology of diseases and organs such as kidney and liver.

关键词： magnetic resonance image Metal-organic frameworks Longitudinal relaxation rates

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World Journal of Stem Cells 2019年第2期11卷 100-123页

作者： Helio Rodrigues da Silva Javier Bustamante Mamani Mariana Penteado Nucci Leopoldo Penteado Nucci Andrea Tiemi Kondo Daianne Maciely Carvalho Fantacini Lucas Eduardo Botelho de Souza Virginia Picanço-Castro Dimas Tadeu Covas José Mauro Kutner Fernando Anselmo de Oliveira Nelson Hamerschlak Lionel Fernel Gamarra Hospital Israelita Albert Einstein LIM44 Hospital das Clinicas HCFMUSP Faculdade de MedicinaUniversidade de São Paulo Centro Universitário do Planalto Central Faculdade de Medicina de Ribeirão Preto Universidade de São Paulo

BACKGROUND Mesenchymal stem cells(MSCs) have been widely tested for their therapeutic efficacy in the ischemic brain and have been shown to provide several benefits. A major obstacle to the clinical translation of these therapies has been the inability to noninvasively monitor the best route, cell doses, and collateral effects while ensuring the survival and effective biological functioning of the transplanted stem cells. Technological advances in multimodal imaging have allowed in vivo monitoring of the biodistribution and viability of transplanted stem cells due to a combination of imaging technologies associated with multimodal nanoparticles(MNPs) using new labels and covers to achieve low toxicity and longtime residence in *** To evaluate the sensitivity of triple-modal imaging of stem cells labeled with MNPs and applied in a stroke *** After the isolation and immunophenotypic characterization of human bonemarrow MSCs(hBM-MSCs), our team carried out lentiviral transduction of these cells for the evaluation of bioluminescent images(BLIs) in vitro and in vivo. In addition, MNPs that were previously characterized(regarding hydrodynamic size, zeta potential, and optical properties), and were used to label these cells,analyze cell viability via the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay and BLI analysis, and quantify the internalization process and iron load in different concentrations of MNPs via magnetic resonance imaging(MRI),near-infrared fluorescence(NIRF), and inductively coupled plasma-mass spectrometry(ICP-MS). In in vivo analyses, the same labeled cells were implanted in a sham group and a stroke group at different times and under different MNP concentrations(after 4 h or 6 d of cell implantation) to evaluate the sensitivity of triple-modal *** hBM-MSC collection and isolation after immunophenotypic characterization were demonstrated to be adequate in hBM samples. After transduction of these cells with

关键词： Multimodal nanoparticles Human bone marrow mesenchymal stem cells Near-infrared fluorescence image magnetic resonance image Bioluminescence Stroke

Primary angiitis of the central nervous system： a case report

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Chinese Medical Journal 2011年第17期124卷 2782-2785页

作者： YU Xiao-lin LIU Ai-fen MA Lin YAN Chuan-zhu ZHAO Yu-ying SHAN Pei-yan Department of Geriatrics Qilu Hospital of Shandong University Jinan Shandong 250012 China Department of Neurology Qilu Hospital of Shandong University Jinan Shandong 250012 China

Primary angiitis of the central nervous system is a rare and difficult entity. Here we represented the clinical and pathological features of a patient with little response to steroid before definite diagnosis. The 50-year-old male had a fluctuating disease course for more than 3 years. He presented visual disorders, seizure, cognitive impairment, hypersomnia, unsteady gait, dysphasia, dysphagia, and incontinence. magnetic resonance imaging showed multiple, supratentorial and infratentorial abnormal signals, while cerebrospinal fluid and cerebral angiography were normal. magnetic resonance spectrum showed a decrease of N-acetyl-aspartate. Brain biopsy revealed nongranulomatous lymphatic vasculitis with reactive gliosis, cicatrization, demyelination and focal hemorrhages.

关键词： primary angiitis of the central nervous system clinical manifestation magnetic resonance image histopathology

Enlarged pancreas: not always a cancer

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Hepatobiliary & Pancreatic Diseases International 2015年第1期14卷 107-108页

作者： Lucia Calculli Davide Festi Raffaele Pezzilli Departments of Radiology Sant'Orsola-Malpighi Hospital Digestive Diseases Sant'Orsola-Malpighi Hospital Internal Medicine Sant'Orsola-Malpighi Hospital

Pancreatic fat accumulation has been described with various terms including pancreatic lipomatosis, pancreatic steatosis, fatty replacement, fatty infiltration, fatty pancreas, lipomatous pseudohypertrophy and nonalcoholic fatty pancreas disease. It has been reported to be associated with type 2 diabetes mellitus, acute pancreatitis, pancreatic cancer and the formation of pancreatic fistula. The real incidence of this condition is still unknown. We report a case of pancreatic steatosis in a non-obese female patient initially diagnosed with a mass in the head of the pancreas. magnetic resonance imaging（MRI） was carried out to define the characteristics of the pancreatic mass. MRI confirmed the diagnosis of fat pancreas. Enlarged pancreas is not always a cancer, but pancreatic steatosis is characterized by pancreatic enlargement. MRI could give a definite diagnosis of pancreatic steatosis or cancer.

关键词： pancreatic steatosis magnetic resonance image computer tomography IgG4 differential diagnosis clinical course