scholarly journals A new method for accurate in vivo mapping of human brain connections using microstructural and anatomical information

2020 ◽  
Vol 6 (31) ◽  
pp. eaba8245 ◽  
Author(s):  
Simona Schiavi ◽  
Mario Ocampo-Pineda ◽  
Muhamed Barakovic ◽  
Laurent Petit ◽  
Maxime Descoteaux ◽  
...  
Keyword(s):  
Human Brain ◽  
Imaging Modality ◽  
Brain Anatomy ◽  
Major Step ◽  
Wide Range ◽  
Noninvasive Imaging Modality ◽  
Novel Processing ◽  
Brain Data ◽  
Anatomical Information

Diffusion magnetic resonance imaging is a noninvasive imaging modality that has been extensively used in the literature to study the neuronal architecture of the brain in a wide range of neurological conditions using tractography. However, recent studies highlighted that the anatomical accuracy of the reconstructions is inherently limited and challenged its appropriateness. Several solutions have been proposed to tackle this issue, but none of them proved effective to overcome this fundamental limitation. In this work, we present a novel processing framework to inject into the reconstruction problem basic prior knowledge about brain anatomy and its organization and evaluate its effectiveness using both simulated and real human brain data. Our results indicate that our proposed method dramatically increases the accuracy of the estimated brain networks and, thus, represents a major step forward for the study of connectivity.

scholarly journals Oligomerization of Paramagnetic Substrates Result in Signal Amplification and Can be Used for MR Imaging of Molecular Targets

2002 ◽  
Vol 1 (1) ◽  
pp. 153535002002000 ◽  
Author(s):  
Alexei Bogdanov ◽  
Lars Matuszewski ◽  
Christoph Bremer ◽  
Alexander Petrovsky ◽  
Ralph Weissleder
Keyword(s):  
Signal Amplification ◽  
Imaging Modality ◽  
Functional Characterization ◽  
Molecular Targets ◽  
Transgenic Animals ◽  
Rotational Correlation Time ◽  
In Vivo Detection ◽  
Noninvasive Imaging Modality ◽  
Magnetic Resonance Imaging Mri

Magnetic resonance imaging (MRI) has evolved into a sophisticated, noninvasive imaging modality capable of high-resolution anatomical and functional characterization of transgenic animals. To expand the capabilities MRI, we have developed a novel MR signal amplification (MRamp) strategy based on enzyme-mediated polymerization of paramagnetic substrates into oligomers of higher magnetic relaxivity. The substrates consist of chelated gadolinium covalently bound to phenols, which then serve as electron donors during enzymatic hydrogen peroxide reduction by peroxidase. The converted monomers undergo rapid condensation into paramagnetic oligomers leading to a threefold increase in atomic relaxivity ( R1/Gd). The observed relaxivity changes are largely due to an increase in the rotational correlation time τr of the lanthanide. Three applications of the developed system are demonstrated: (1) imaging of nanomolar amounts of an oxidoreductase (peroxidase); (2) detection of a model ligand using an enzyme-linked immunoadsorbent assay format; and (3) imaging of E-selectin on the surface of endothelial cells probed for with an anti-E-selectin – peroxidase conjugate. The development of “enzyme sensing” probes is expected to have utility for a number of applications including in vivo detection of specific molecular targets. One particular advantage of the MRamp technique is that the same paramagnetic substrate can be potentially used to identify different molecular targets by attaching enzymes to various antibodies or other target-seeking molecules.

scholarly journals Data integration through brain atlasing: Human Brain Project tools and strategies

2018 ◽  
Vol 50 ◽  
pp. 70-76 ◽  
Author(s):  
Ingvild E. Bjerke ◽  
Martin Øvsthus ◽  
Eszter A. Papp ◽  
Sharon C. Yates ◽  
Ludovico Silvestri ◽  
...  
Keyword(s):  
Human Brain ◽  
Three Dimensional ◽  
Anatomical Location ◽  
Data Systems ◽  
Data Types ◽  
Online Data ◽  
Human Brain Project ◽  
Wide Range ◽  
Brain Data ◽  
The Brain

AbstractThe Human Brain Project (HBP), an EU Flagship Initiative, is currently building an infrastructure that will allow integration of large amounts of heterogeneous neuroscience data. The ultimate goal of the project is to develop a unified multi-level understanding of the brain and its diseases, and beyond this to emulate the computational capabilities of the brain. Reference atlases of the brain are one of the key components in this infrastructure. Based on a new generation of three-dimensional (3D) reference atlases, new solutions for analyzing and integrating brain data are being developed. HBP will build services for spatial query and analysis of brain data comparable to current online services for geospatial data. The services will provide interactive access to a wide range of data types that have information about anatomical location tied to them. The 3D volumetric nature of the brain, however, introduces a new level of complexity that requires a range of tools for making use of and interacting with the atlases. With such new tools, neuroscience research groups will be able to connect their data to atlas space, share their data through online data systems, and search and find other relevant data through the same systems. This new approach partly replaces earlier attempts to organize research data based only on a set of semantic terminologies describing the brain and its subdivisions.

scholarly journals Ranking diffusion-MRI models with in-vivo human brain data

2013 ◽  
Author(s):  
Uran Ferizi ◽  
Torben Schneider ◽  
Eleftheria Panagiotaki ◽  
Gemma Nedjati-Gilani ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Human Brain ◽  
Diffusion Mri ◽  
Brain Data

scholarly journals A ranking of diffusion MRI compartment models with in vivo human brain data

2013 ◽  
Vol 72 (6) ◽  
pp. 1785-1792 ◽  
Author(s):  
Uran Ferizi ◽  
Torben Schneider ◽  
Eleftheria Panagiotaki ◽  
Gemma Nedjati-Gilani ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Human Brain ◽  
Diffusion Mri ◽  
Compartment Models ◽  
Brain Data

scholarly journals Multimodality molecular imaging: Paving the way for personalized medicine

2017 ◽  
Vol 1 (3) ◽  
pp. 44
Author(s):  
Habib Zaidi
Keyword(s):  
Molecular Imaging ◽  
Molecular Level ◽  
Multimodality Imaging ◽  
Imaging Modality ◽  
Tracer Uptake ◽  
Combined System ◽  
Quantitative Pet ◽  
Simultaneous Acquisition ◽  
Anatomical Information

Early diagnosis and therapy increasingly operate at the cellular, molecular or even at the genetic level. As diagnostic techniques transition from the systems to the molecular level, the role of multimodality molecular imaging becomes increasingly important. Positron emission tomography (PET), x-ray CT and MRI are powerful techniques for in vivo imaging. The inability of PET to provide anatomical information is a major limitation of standalone PET systems. Combining PET and CT proved to be clinically relevant and successfully reduced this limitation by providing the anatomical information required for localization of metabolic abnormalities. However, this technology still lacks the excellent soft-tissue contrast provided by MRI. Standalone MRI systems reveal structure and function, but cannot provide insight into the physiology and/or the pathology at the molecular level. The combination of PET and MRI, enabling truly simultaneous acquisition, bridges the gap between molecular and systems diagnosis. MRI and PET offer richly complementary functionality and sensitivity; fusion into a combined system offering simultaneous acquisition will capitalize the strengths of each, providing a hybrid technology that is greatly superior to the sum of its parts. This talk also reflects the tremendous increase in interest in quantitative molecular imaging using PET as both clinical and research imaging modality in the past decade. It offers a brief overview of the entire range of quantitative PET imaging from basic principles to various steps required for obtaining quantitatively accurate data from dedicated standalone PET and combined PET/CT and PET/MR systems including algorithms used to correct for physical degrading factors and to quantify tracer uptake and volume for radiation therapy treatment planning. Future opportunities and the challenges facing the adoption of multimodality imaging technologies and their role in biomedical research will also be addressed.

scholarly journals A multimodal computational pipeline for 3D histology of the human brain

2020 ◽  
Author(s):  
Matteo Mancini ◽  
Adrià Casamitjana ◽  
Loic Peter ◽  
Eleanor Robinson ◽  
Shauna Crampsie ◽  
...  
Keyword(s):  
Human Brain ◽  
Ex Vivo ◽  
Imaging Modality ◽  
3D Structure ◽  
Microscopic Level ◽  
Level Of Detail ◽  
Computational Pipeline ◽  
Volumetric Mri ◽  
Mri Scan

AbstractEx vivo imaging enables analysis of the human brain at a level of detail that is not possible in vivo with MRI. In particular, histology can be used to study brain tissue at the microscopic level, using a wide array of different stains that highlight different microanatomical features. Complementing MRI with histology has important applications in ex vivo atlas building and in modeling the link between microstructure and macroscopic MR signal. However, histology requires sectioning tissue, hence distorting its 3D structure, particularly in larger human samples. Here, we present an open-source computational pipeline to produce 3D consistent histology reconstructions of the human brain. The pipeline relies on a volumetric MRI scan that serves as undistorted reference, and on an intermediate imaging modality (blockface photography) that bridges the gap between MRI and histology. We present results on 3D histology reconstruction of a whole human hemisphere.

scholarly journals Waterproof Galvanometer Scanner-Based Handheld Photoacoustic Microscopy Probe for Wide-Field Vasculature Imaging In Vivo

Photonics ◽  
2021 ◽  
Vol 8 (8) ◽  
pp. 305
Author(s):  
Daewoon Seong ◽  
Sangyeob Han ◽  
Jaeyul Lee ◽  
Euimin Lee ◽  
Yoonseok Kim ◽  
...  
Keyword(s):  
Imaging Modality ◽  
Wide Field ◽  
Photoacoustic Microscopy ◽  
Label Free ◽  
Experimental Conditions ◽  
Sample Shape ◽  
Mouse Tissues ◽  
Wide Range ◽  
Galvanometer Scanner

Photoacoustic imaging (PAI) is a hybrid non-invasive imaging technique used to merge high optical contrast and high acoustic resolution in deep tissue. PAI has been extensively developed by utilizing its advantages that include deep imaging depth, high resolution, and label-free imaging. As a representative implementation of PAI, photoacoustic microscopy (PAM) has been used in preclinical and clinical studies for its micron-scale spatial resolution capability with high optical absorption contrast. Several handheld and portable PAM systems have been developed that improve its applicability to several fields, making it versatile. In this study, we developed a laboratory-customized, two-axis, waterproof, galvanometer scanner-based handheld PAM (WP-GVS-HH-PAM), which provides an extended field of view (14.5 × 9 mm2) for wide-range imaging. The fully waterproof handheld probe enables free movement for imaging regardless of sample shape, and volume rate and scanning region are adjustable per experimental conditions. Results of WP-GVS-HH-PAM-based phantom and in vivo imaging of mouse tissues (ear, iris, and brain) confirm the feasibility and applicability of our system as an imaging modality for various biomedical applications.

The Importance of Being Dispersed: A Ranking of Diffusion MRI Models for Fibre Dispersion Using In Vivo Human Brain Data

2013 ◽  
pp. 74-81 ◽  
Author(s):  
Uran Ferizi ◽  
Torben Schneider ◽  
Maira Tariq ◽  
Claudia A. M. Wheeler-Kingshott ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Human Brain ◽  
Diffusion Mri ◽  
Brain Data

Evaluation of 99mTc-Label led Vitamin K4 as an Agent for Testicular Imaging

1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan
Keyword(s):  
Soft Tissue ◽  
Room Temperature ◽  
Normal Subjects ◽  
Left Testis ◽  
Wide Range ◽  
Activity Ratios ◽  
The Right ◽  
Radioactivity Levels

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.

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