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Elyria, OH, United States

Penet M.-F.,Johns Hopkins University | Artemov D.,Johns Hopkins University | Farahani K.,Guided Interventions | Bhujwalla Z.M.,Johns Hopkins University
NMR in Biomedicine | Year: 2013

Probe development is a critical component in cancer imaging, and novel probes are making major inroads in several aspects of cancer detection and image-guided treatments. Intrinsic MR probes such as signals from metabolites and their chemical shifts have been used for more than a decade to understand cancer physiology and metabolism. Through the integration of technology, molecular biology, and chemistry, the last few years have witnessed an explosion of extrinsic probes for molecular and functional imaging of cancer that, together with techniques such as CEST and hyperpolarization, have significantly expanded the repertoire of MR techniques in basic and translational investigations of many different aspects of cancer. Furthermore, incorporation of MR probes into multifunctional nanoparticles and multimodality imaging platforms have opened new opportunities for MR in image-guided diagnosis and therapy of cancer. Here we have provided an overview of recent innovations that have occurred in the development of MRI probes for molecular and functional imaging of cancer. Although most of these novel probes are not clinically available, they offer significant promise for future translational applications. In this review, we have highlighted the areas of future development that are likely to have a profound impact on cancer detection and treatment. Copyright © 2013 John Wiley & Sons, Ltd. Probe development is a critical component in cancer imaging, and novel probes are making major inroads in several aspects of cancer detection and image-guided treatments. In this review, we have provided an overview of recent innovations that have occurred in the development of MRI probes for molecular and functional imaging of cancer. Although most of these novel probes are not clinically available, they offer significant promise for future translational applications. © 2013 John Wiley & Sons, Ltd.. Source


Xu S.,Philips | Yung R.C.,Pulmonary Oncology | Gutierrez L.F.,Guided Interventions | McVeigh E.R.,Depat. of Biomedical Engineering
2010 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBC'10 | Year: 2010

In X-ray guided bronchoscopy of peripheral pulmonary lesions, airways and nodules are hardly visible in X-ray images. Transbronchial biopsy of peripheral lesions is often carried out blindly, resulting in degraded diagnostic yield. One solution of this problem is to superimpose the lesions and airways segmented from preoperative 3D CT images onto 2D X-ray images. A feature-based 2D/3D registration method is proposed for the image fusion between the datasets of the two imaging modalities. Two stereo X-ray images are used in the algorithm to improve the accuracy and robustness of the registration. The algorithm extracts the edge features of the bony structures from both CT and X-ray images. The edge points from the X-ray images are categorized into eight groups based on the orientation information of their image gradients. An orientation dependent Euclidean distance map is generated for each group of X-ray feature points. The distance map is then applied to the edge points of the projected CT images whose gradient orientations are compatible with the distance map. The CT and X-ray images are registered by matching the boundaries of the projected CT segmentations to the closest edges of the X-ray images after the orientation constraint is satisfied. Phantom and clinical studies were carried out to validate the algorithm's performance, showing a registration accuracy of 4.19(±0.5) mm with 48.39(±9.6) seconds registration time. The algorithm was also evaluated on clinical data, showing promising registration accuracy and robustness. © 2010 IEEE. Source


Capozzi A.,Ecole Polytechnique Federale de Lausanne | Hyacinthe J.-N.,University of Applied Sciences and Arts Western Switzerland | Hyacinthe J.-N.,Guided Interventions | Cheng T.,Ecole Polytechnique Federale de Lausanne | And 6 more authors.
Journal of Physical Chemistry C | Year: 2015

Hyperpolarization via dissolution dynamic nuclear polarization (DNP) is a versatile method to dramatically enhance the liquid-state NMR signal of X-nuclei and can be used for performing metabolic and molecular imaging. It was recently demonstrated that instead of incorporating persistent radicals as source of unpaired electron spins, required for DNP, nonpersistent radicals can be photoinduced in frozen beads of neat pyruvic acid (PA), the most common substrate for metabolic imaging. In the present work, it is shown that the same radicals can be created in frozen solutions containing a fraction of PA in addition to 13C- or 6Li-labeled salts or 129Xe nuclei. The use of these nonpersistent radicals prevents the loss of a substantial part of the polarization during the transfer of hyperpolarized solutions into iron-shielded high-field MRI scanners. It is also demonstrated that UV-irradiated d4-PA yields nonpersistent radicals exhibiting similarities with the most efficient and widely used persistent trityl radicals. © 2015 American Chemical Society. Source


Chapman S.,U.S. National Cancer Institute | Dobrovolskaia M.,SAIC | Farahani K.,Guided Interventions | Goodwin A.,University of Colorado at Boulder | And 12 more authors.
Nano Today | Year: 2013

Recent advances in molecular imaging and nanotechnology are providing new opportunities for biomedical imaging with great promise for the development of novel imaging agents. The unique optical, magnetic, and chemical properties of materials at the scale of nanometers allow the creation of imaging probes with better contrast enhancement, increased sensitivity, controlled biodistribution, better spatial and temporal information, multi-functionality and multi-modal imaging across MRI, PET, SPECT, and ultrasound. These features could ultimately translate to clinical advantages such as earlier detection, real time assessment of disease progression and personalized medicine. However, several years of investigation into the application of these materials to cancer research has revealed challenges that have delayed the successful application of these agents to the field of biomedical imaging. Understanding these challenges is critical to take full advantage of the benefits offered by nano-sized imaging agents. Therefore, this article presents the lessons learned and challenges encountered by a group of leading researchers in this field, and suggests ways forward to develop nanoparticle probes for cancer imaging. © 2013 Elsevier Ltd. All rights reserved. Source


A guide wire has a distal end incorporating a coil and a capacitive element that form a resonance circuit with a resonance frequency that is responsive to the pressure of blood external to the guide wire. The resonance frequency can be detected wirelessly, or through two contacts at the proximal wire end, or through one brush contact located inside an insertion sheath and a ground electrode. Wireless detection can be implemented via a second resonance circuit, and electronics for determining the frequency when the first and second circuits are in resonance with each other.

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