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Singh S, Singh R, Luthra S, Singla A, Tanvir F, Antaal H, Singh A, Singh H, Singh J, Kaur MS. Evolving Radiological Approaches in the Diagnosis and Monitoring of Arachnoiditis Ossificans. Cureus 2024; 16:e68399. [PMID: 39355477 PMCID: PMC11444744 DOI: 10.7759/cureus.68399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2024] [Indexed: 10/03/2024] Open
Abstract
Arachnoiditis ossificans (AO) is a rare and complex neurological condition characterized by pathological calcification or ossification of the arachnoid membrane. Arachnoiditis ranks as the third most frequent cause of failed back surgery syndrome (FBSS). This narrative review explores the evolving radiological approaches in its diagnosis and monitoring. The historical perspective traces the progression from plain radiographs to advanced imaging techniques. Current radiological modalities, including X-ray, computed tomography (CT), and magnetic resonance imaging (MRI), are discussed, highlighting their respective roles, advantages, and limitations. Emerging and advanced imaging modalities, such as high-resolution CT, 3T and 7T MRI, and PET/CT or PET/MRI, are examined for their potential to enhance diagnostic accuracy and monitoring capabilities. A comparative analysis of these imaging modalities considers their sensitivity, specificity, cost-effectiveness, and radiation exposure implications. The review also explores the crucial role of imaging in disease monitoring and treatment planning, including follow-up protocols, evaluation of disease progression, and guidance for interventional procedures. Future directions in the field are discussed, focusing on promising research areas, the potential of artificial intelligence and machine learning in image analysis, and identified gaps in current knowledge. The review emphasizes the importance of a multimodal imaging approach and the need for standardized protocols. It concludes that while significant advancements have been made, further research is necessary to fully understand the correlation between imaging findings and clinical outcomes. The continued evolution of radiological approaches is expected to significantly improve patient care and outcomes in AO.
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Affiliation(s)
- Sumerjit Singh
- Diagnostic Radiology, Government Medical College Amritsar, Amritsar, IND
| | - Ripudaman Singh
- Internal Medicine, Government Medical College Amritsar, Amritsar, IND
| | - Shivansh Luthra
- Medicine, Government Medical College Amritsar, Amritsar, IND
| | | | - Fnu Tanvir
- Internal Medicine, Government Medical College Amritsar, Amritsar, IND
| | - Harman Antaal
- Internal Medicine, Government Medical College Patiala, Patiala, IND
| | - Agamjit Singh
- Psychiatry, Punjab Institute of Medical Sciences, Jalandhar, IND
| | - Harmanjot Singh
- Internal Medicine, The White Medical College and Hospital, Bungal, IND
| | - Jaskaran Singh
- Internal Medicine, Sri Guru Ram Das University of Health Sciences and Research, Amritsar, IND
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Frencken AL, Richtsmeier D, Leonard RL, Williams AG, Johnson CE, Johnson JA, Blasiak B, Orlef A, Skorupa A, Sokół M, Tomanek B, Beckham W, Bazalova-Carter M, van Veggel FCJM. X-ray-Sensitive Doped CaF 2-Based MRI Contrast Agents for Local Radiation Dose Measurement. ACS APPLIED MATERIALS & INTERFACES 2024; 16:13453-13465. [PMID: 38445594 DOI: 10.1021/acsami.3c16336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
Ionizing radiation has become widely used in medicine, with application in diagnostic techniques, such as computed tomography (CT) and radiation therapy (RT), where X-rays are used to diagnose and treat tumors. The X-rays used in CT and, in particular, in RT can have harmful side effects; hence, an accurate determination of the delivered radiation dose is of utmost importance to minimize any damage to healthy tissues. For this, medical specialists mostly rely on theoretical predictions of the delivered dose or external measurements of the dose. To extend the practical use of ionizing radiation-based medical techniques, such as magnetic resonance imaging (MRI)-guided RT, a more precise measurement of the internal radiation dose internally is required. In this work, a novel approach is presented to measure dose in liquids for potential future in vivo applications. The strategy relies on MRI contrast agents (CAs) that provide a dose-sensitive signal. The demonstrated materials are (citrate-capped) CaF2 nanoparticles (NPs) doped with Eu3+ or Fe2+/Fe3+ ions. Free electrons generated by ionizing radiation allow the reduction of Eu3+, which produces a very small contrast in MRI, to Eu2+, which induces a strong contrast. Oxidative species generated by high-energy X-rays can be measured indirectly using Fe2+ because it oxidizes to Fe3+, increasing the contrast in MRI. Notably, in the results, a strong increase in the proton relaxation rates is observed for the Eu3+-doped NPs at 40 kV. At 6 MV, a significant increase in proton relaxation rates is observed using CaF2 NPs doped with Fe2+/Fe3+ after irradiation. The presented concept shows great promise for use in the clinic to measure in vivo local ionizing radiation dose, as these CAs can be intravenously injected in a saline solution.
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Affiliation(s)
- Adriaan L Frencken
- Department of Chemistry, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- Centre for Advanced Materials & Related Technologies (CAMTEC), University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Devon Richtsmeier
- Centre for Advanced Materials & Related Technologies (CAMTEC), University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - R Lee Leonard
- Aerospace and Biomedical Engineering, The University of Tennessee Space Institute Tullahoma, Tullahoma, Tennessee 37388-9700, United States
| | - Aleia G Williams
- Aerospace and Biomedical Engineering, The University of Tennessee Space Institute Tullahoma, Tullahoma, Tennessee 37388-9700, United States
| | - Charles E Johnson
- Aerospace and Biomedical Engineering, The University of Tennessee Space Institute Tullahoma, Tullahoma, Tennessee 37388-9700, United States
| | - Jacqueline A Johnson
- Aerospace and Biomedical Engineering, The University of Tennessee Space Institute Tullahoma, Tullahoma, Tennessee 37388-9700, United States
| | - Barbara Blasiak
- Experimental Imaging Centre, University of Calgary, Calgary, Alberta T2N 4N1, Canada
- Institute of Nuclear Physics, Polish Academy of Sciences, Krakow 31-342, Poland
| | - Andrzej Orlef
- Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice Branch, 44-102 Gliwice, Poland
| | - Agnieszka Skorupa
- Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice Branch, 44-102 Gliwice, Poland
| | - Maria Sokół
- Department of Medical Physics, Maria Skłodowska-Curie National Research Institute of Oncology, Gliwice Branch, 44-102 Gliwice, Poland
| | - Boguslaw Tomanek
- Experimental Imaging Centre, University of Calgary, Calgary, Alberta T2N 4N1, Canada
- Institute of Nuclear Physics, Polish Academy of Sciences, Krakow 31-342, Poland
- Oncology Department, University of Alberta, 8303-112 Street NW, Edmonton, Alberta T6G 2T4, Canada
| | - Wayne Beckham
- BC Cancer, Royal Jubilee Hospital, Victoria, British Columbia V8R 6 V5, Canada
| | - Magdalena Bazalova-Carter
- Centre for Advanced Materials & Related Technologies (CAMTEC), University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
| | - Frank C J M van Veggel
- Department of Chemistry, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- Centre for Advanced Materials & Related Technologies (CAMTEC), University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
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Farjadian F, Faghih Z, Fakhimi M, Iranpour P, Mohammadi-Samani S, Doroudian M. Glucosamine-Modified Mesoporous Silica-Coated Magnetic Nanoparticles: A "Raisin-Cake"-like Structure as an Efficient Theranostic Platform for Targeted Methotrexate Delivery. Pharmaceutics 2023; 15:2491. [PMID: 37896251 PMCID: PMC10610088 DOI: 10.3390/pharmaceutics15102491] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/11/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
This study presents the synthesis of glucosamine-modified mesoporous silica-coated magnetic nanoparticles (MNPs) as a therapeutic platform for the delivery of an anticancer drug, methotrexate (MTX). The MNPs were coated with mesoporous silica in a templated sol-gel process to form MNP@MSN, and then chloropropyl groups were added to the structure in a post-modification reaction. Glucosamine was then reacted with the chloro-modified structure, and methotrexate was conjugated to the hydroxyl group of the glucose. The prepared structure was characterized using techniques such as Fourier transform infrared (FT-IR) spectroscopy, elemental analysis (CHN), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), a vibrating sample magnetometer (VSM), and X-ray diffraction (XRD). Good formation of nano-sized MNPs and MNP@MSN was observed via particle size monitoring. The modified glucosamine structure showed a controlled release profile of methotrexate in simulated tumor fluid. In vitro evaluation using the 4T1 breast cancer cell line showed the cytotoxicity, apoptosis, and cell cycle effects of methotrexate. The MTT assay showed comparable toxicity between MTX-loaded nanoparticles and free MTX. The structure could act as a glucose transporter-targeting agent and showed increased uptake in cancer cells. An in vivo breast cancer model was established in BALB/C mice, and the distribution of MTX-conjugated MNP@MSN particles was visualized using MRI. The MTX-conjugated particles showed significant anti-tumor potential together with MRI contrast enhancement.
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Affiliation(s)
- Fatemeh Farjadian
- Pharmaceutical Sciences Research Canter, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz 71468-64685, Iran;
| | - Zahra Faghih
- Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz 71348-45550, Iran; (Z.F.); (M.F.)
| | - Maryam Fakhimi
- Shiraz Institute for Cancer Research, School of Medicine, Shiraz University of Medical Sciences, Shiraz 71348-45550, Iran; (Z.F.); (M.F.)
| | - Pooya Iranpour
- Medical Imaging Research Center, Department of Radiology, Shiraz University of Medical Sciences, Shiraz 71936-13311, Iran;
| | - Soliman Mohammadi-Samani
- Pharmaceutical Sciences Research Canter, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz 71468-64685, Iran;
- Department of Pharmaceutics, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz 71468-64685, Iran
| | - Mohammad Doroudian
- Department of Cell and Molecular Sciences, Faculty of Biological Sciences, Kharazmi University, Tehran 15719-14911, Iran
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Fang Y, Sun Y, Liu Y, Liu T, Hao W, Liao Y. Neurobiological mechanisms and related clinical treatment of addiction: a review. PSYCHORADIOLOGY 2022; 2:180-189. [PMID: 38665277 PMCID: PMC10917179 DOI: 10.1093/psyrad/kkac021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 04/28/2024]
Abstract
Drug addiction or substance use disorder (SUD), has been conceptualized as a three-stage (i.e. binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation/craving) recurring cycle that involves complex changes in neuroplasticity, reward, motivation, desire, stress, memory, and cognitive control, and other related brain regions and brain circuits. Neuroimaging approaches, including magnetic resonance imaging, have been key to mapping neurobiological changes correlated to complex brain regions of SUD. In this review, we highlight the neurobiological mechanisms of these three stages of addiction. The abnormal activity of the ventral tegmental, nucleus accumbens, and caudate nucleus in the binge/intoxication stage involve the reward circuit of the midbrain limbic system. The changes in the orbitofrontal cortex, dorsolateral prefrontal cortex, amygdala, and hypothalamus emotional system in the withdrawal/negative affect stage involve increases in negative emotional states, dysphoric-like effects, and stress-like responses. The dysregulation of the insula and prefrontal lobes is associated with craving in the anticipation stage. Then, we review the present treatments of SUD based on these neuroimaging findings. Finally, we conclude that SUD is a chronically relapsing disorder with complex neurobiological mechanisms and multimodal stages, of which the craving stage with high relapse rate may be the key element in treatment efficacy of SUD. Precise interventions targeting different stages of SUD and characteristics of individuals might serve as a potential therapeutic strategy for SUD.
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Affiliation(s)
- Yehong Fang
- Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 3 East Qingchun Road, Hangzhou, Zhejiang 310016, China
| | - Yunkai Sun
- Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 3 East Qingchun Road, Hangzhou, Zhejiang 310016, China
| | - Yi Liu
- Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 3 East Qingchun Road, Hangzhou, Zhejiang 310016, China
| | - Tieqiao Liu
- Department of Psychiatry & Mental Health Institute of the Second Xiangya Hospital, Central South University. National Clinical Research Center on Mental Disorders & National Technology Institute on Mental Disorders. Hunan Key Laboratory of Psychiatry and Mental Health, 139 Renmin (M) Rd, Changsha, Hunan 410011, P. R. China
| | - Wei Hao
- Department of Psychiatry & Mental Health Institute of the Second Xiangya Hospital, Central South University. National Clinical Research Center on Mental Disorders & National Technology Institute on Mental Disorders. Hunan Key Laboratory of Psychiatry and Mental Health, 139 Renmin (M) Rd, Changsha, Hunan 410011, P. R. China
| | - Yanhui Liao
- Department of Psychiatry, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, 3 East Qingchun Road, Hangzhou, Zhejiang 310016, China
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Compact pediatric cardiac magnetic resonance imaging protocols. Pediatr Radiol 2022:10.1007/s00247-022-05447-y. [PMID: 35821442 DOI: 10.1007/s00247-022-05447-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/25/2022] [Accepted: 06/30/2022] [Indexed: 10/17/2022]
Abstract
Cardiac MRI is in many respects an ideal modality for pediatric cardiovascular imaging, enabling a complete noninvasive assessment of anatomy, morphology, function and flow in one radiation-free and potentially non-contrast exam. Nonetheless, traditionally lengthy and complex imaging acquisition strategies have often limited its broader use beyond specialized centers. In this review, the author presents practical cardiac MRI imaging protocols to facilitate the performance of succinct yet successful exams that provide the most salient clinical data for the majority of congenital and acquired pediatric cardiac disease. In addition, the author reviews newer and evolving techniques that permit more rapid but similarly diagnostic MRI, including compressed sensing and artificial intelligence/machine learning reconstruction, four-dimensional flow acquisition and blood pool contrast agents. With the modern armamentarium of cardiac MRI methods, the goal of compact yet comprehensive exams in children can now be realized.
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Abstract
Proteins play a key role in living organisms. The study of proteins and their dynamics provides information about their functionality, catalysis and potential alterations towards pathological diseases. Several techniques are used for studying protein dynamics, e.g., magnetic resonance, fluorescence imaging techniques, mid-infrared spectroscopy and biochemical assays. Spectroscopic analysis, based on the use of terahertz (THz) radiation with frequencies between 0.1 and 15 THz (3–500 cm−1), was underestimated by the biochemical community. In recent years, however, the potential of THz spectroscopy in the analysis of both simple structures, such as polypeptide molecules, and complex structures, such as protein complexes, has been demonstrated. The THz absorption spectrum provides some information on proteins: for small molecules the THz spectrum is dominated by individual modes related to the presence of hydrogen bonds. For peptides, the spectral information concerns their secondary structure, while for complex proteins such as globular proteins and viral glycoproteins, spectra also provide information on collective modes. In this short review, we discuss the results obtained by THz spectroscopy in the protein dynamics investigations. In particular, we will illustrate advantages and applications of THz spectroscopy, pointing out the complementary information it may provide.
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7
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Abstract
In this review, the roles of detectors in various medical imaging techniques were described. Ultrasound, optical (near-infrared spectroscopy and optical coherence tomography) and thermal imaging, magnetic resonance imaging, computed tomography, single-photon emission tomography, positron emission tomography were the imaging modalities considered. For each methodology, the state of the art of detectors mainly used in the systems was described, emphasizing new technologies applied.
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8
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Saluja V, Mishra Y, Mishra V, Giri N, Nayak P. Dendrimers based cancer nanotheranostics: An overview. Int J Pharm 2021; 600:120485. [PMID: 33744447 DOI: 10.1016/j.ijpharm.2021.120485] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 02/26/2021] [Accepted: 03/09/2021] [Indexed: 12/12/2022]
Abstract
Cancer is a known deadliest disease that requires a judicious diagnostic, targeting, and treatment strategy for an early prognosis and selective therapy. The major pitfalls of the conventional approach are non-specificity in targeting, failure to precisely monitor therapy outcome, and cancer progression leading to malignancies. The unique physicochemical properties offered by nanotechnology derived nanocarriers have the potential to radically change the landscape of cancer diagnosis and therapeutic management. An integrative approach of utilizing both diagnostic and therapeutic functionality using a nanocarrier is termed as nanotheranostic. The nanotheranostics platform is designed in such a way that overcomes various biological barriers, efficiently targets the payload to the desired locus, and simultaneously supports planning, monitoring, and verification of treatment delivery to demonstrate an enhanced therapeutic efficacy. Thus, a nanotheranostic platform could potentially assist in drug targeting, image-guided focal therapy, drug release and distribution monitoring, predictionof treatment response, and patient stratification. A class of highly branched nanocarriers known as dendrimers is recognized as an advanced nanotheranostic platform that has the potential to revolutionize the oncology arena by its unique and exciting features. A dendrimer is a well-defined three-dimensional globular chemical architecture with a high level of monodispersity, amenability of precise size control, and surface functionalization. All the dendrimer properties exhibit a reproducible pharmacokinetic behavior that could ensure the desired biodistribution and efficacy. Dendrimers are thus being exploited as a nanotheranostic platform embodying a diverse class of therapeutic, imaging, and targeting moieties for cancer diagnosis and treatment.
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Affiliation(s)
- Vikrant Saluja
- Faculty of Pharmaceutical Sciences, PCTE Group of Institutes, Ludhiana, Punjab, India; School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
| | - Yachana Mishra
- Department of Zoology, Shri Shakti Degree College, Sankhahari, Ghatampur, Kanpur Nagar, Uttar Pradesh, India
| | - Vijay Mishra
- School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India.
| | - Namita Giri
- College of Pharmacy, Ferris State University, Big Rapids, MI 49307, USA
| | - Pallavi Nayak
- Faculty of Pharmaceutical Sciences, PCTE Group of Institutes, Ludhiana, Punjab, India; School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab, India
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Wood S, Santini T, Krishnamurthy N, Martins T, Farhat N, Ibrahim TS. A comprehensive electromagnetic evaluation of an MRI anthropomorphic head phantom. NMR IN BIOMEDICINE 2021; 34:e4441. [PMID: 33354828 PMCID: PMC8080257 DOI: 10.1002/nbm.4441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 10/15/2020] [Accepted: 10/16/2020] [Indexed: 06/12/2023]
Abstract
Electromagnetic simulations are an important tool for the safety assessment of RF coils. They are a useful resource for MRI RF coil designers, especially when complemented with experimental measurements and testing using physical phantoms. Regular-shaped (spherical/cylindrical) homogeneous phantoms are the MRI standard for RF testing but are somewhat inaccurate when compared with anthropomorphic anatomies, especially at high frequencies. In this work, using a recently developed anthropomorphic heterogeneous human head phantom, studies were performed to analyze the scattering parameters (S-parameters) and the electric and magnetic field distributions using (1) the B1+ field mapping method on a 7 T human MRI scanner and (2) numerical full-wave electromagnetic simulations. All studies used the following: a recently developed six-compartment refillable 3D-printed anthropomorphic head phantom (developed from MRI scans obtained in vivo), where the phantom itself is filled in its entirety with either heterogeneous loading, or homogeneous brain or water loading, in vivo imaging, and a commercial homogeneous spherical water phantom. Our results determined that the calculated S-parameters for all the anthropomorphic head phantom models were comparable to the model that is based on the volunteer (within 17% difference of the reflection coefficient value) but differed for the commercial homogeneous spherical water phantom (within 45% difference). The experimentally measured B1+ field maps of the anthropomorphic heterogeneous and homogeneous brain head phantoms were most comparable to the in vivo measured values. The numerical simulations also show that both the anthropomorphic homogeneous water and brain phantom models were less accurate in terms of electric field intensities/distributions when compared with the segmented in-vivo-based head model and the anthropomorphic heterogeneous head phantom model. The presented data highlights the differences between the physical phantoms/phantom models, and the in vivo measurements/segmented in-vivo-based head model. The results demonstrate the usefulness of 3D-printed anthropomorphic phantoms for RF coil evaluation and testing.
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Affiliation(s)
- Sossena Wood
- University of Pittsburgh, Bioengineering, Pittsburgh, PA, USA
- Carnegie Mellon University, Biomedical Engineering, Pittsburgh, PA, USA
| | - Tales Santini
- University of Pittsburgh, Bioengineering, Pittsburgh, PA, USA
| | | | - Tiago Martins
- University of Pittsburgh, Bioengineering, Pittsburgh, PA, USA
| | - Nadim Farhat
- University of Pittsburgh, Bioengineering, Pittsburgh, PA, USA
| | - Tamer S. Ibrahim
- University of Pittsburgh, Bioengineering, Pittsburgh, PA, USA
- University of Pittsburgh, Psychiatry, Pittsburgh, PA, USA
- University of Pittsburgh, Radiology, Pittsburgh, PA, USA
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Iqbal Z, Arafa ESA, Kanwal Z, Murtaza G. Smart solution of severe problems: Radiolabeled nanocarriers for cancer imaging and therapy. J Drug Deliv Sci Technol 2021. [DOI: 10.1016/j.jddst.2020.102205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Baig MN, Kearns SR, Shannon FJ, Devitt A. Ten Inventions That Shaped Modern Orthopedics. Cureus 2021; 13:e12819. [PMID: 33628685 PMCID: PMC7894968 DOI: 10.7759/cureus.12819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
The current field of orthopedics is the result of many decades of minor and major advancements. The evolution of orthopedics has culminated into the modern field seen today. This article presents 10 inventions that played a key role in shaping modern orthopedics.
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Affiliation(s)
- M N Baig
- Trauma & Orthopaedics, University Hospital Galway, Galway, IRL
| | - S R Kearns
- Trauma & Orthopaedics, University Hospital Galway, Galway, IRL
| | | | - A Devitt
- Trauma & Orthopaedics, University Hospital Galway, Galway, IRL
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12
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Quesada-Olarte JM, Allaf ME, Alvarez-Maestro M, Martínez-Piñeiro L. Molecular imaging of prostate cancer: Review of imaging agents, modalities, and current status. Actas Urol Esp 2020; 44:386-399. [PMID: 32709428 DOI: 10.1016/j.acuro.2019.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 12/17/2019] [Indexed: 11/17/2022]
Abstract
INTRODUCTION The clinical course of Prostate cancer (PCa) are markedly diverse, ranging from indolent to highly aggressive disseminated disease. Molecular imaging techniques are playing an increasing role in early PCa detection, staging and disease recurrence. There are some molecular imaging modalities, radiotracers agents and its performance are important in current clinical practice PCa. OBJECTIVE This review summarizes the latest information regarding molecular imaging of PCa and is designed to assist urologists with ordering and interpreting these modalities and different radiotracers for different patients. EVIDENCE ACQUISITION A PubMed-based literature search was conducted up to September 2019. We selected the most recent and relevant original articles, metanalysis and reviews that have provided relevant information to guide molecular imaging modalities and radiotracers use. EVIDENCE SYNTHESIS In this review, we discuss 3 main molecular imaging modalities and 7 radiotracer technologies available. CONCLUSIONS The use molecular imaging modalities and radiotracers has a unique role in biochemical recurrence and diagnosis of ganglionar and bone progression of PCa. In the present time, no one of these molecular imaging modalities can be recommended over the classical work-up of abdominopelvic CT scan and bone scan, and large-scale and multi-institutional studies are required to validate the efficacy and cost utility of these new technologies.
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Affiliation(s)
| | - M E Allaf
- Departamento de Urología, Johns Hopkins University Hospital, Baltimore, Estados Unidos
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Restivo MC, Ramasawmy R, Bandettini WP, Herzka DA, Campbell-Washburn AE. Efficient spiral in-out and EPI balanced steady-state free precession cine imaging using a high-performance 0.55T MRI. Magn Reson Med 2020; 84:2364-2375. [PMID: 32291845 DOI: 10.1002/mrm.28278] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 03/10/2020] [Accepted: 03/13/2020] [Indexed: 12/22/2022]
Abstract
PURPOSE Low-field MRI offers favorable physical properties for SNR-efficient long readout acquisitions such as spiral and EPI. We used a 0.55 tesla (T) MRI system equipped with high-performance hardware to increase the sampling duty cycle and extend the TR of balanced steady-state free precession (bSSFP) cardiac cine acquisitions, which typically are limited by banding artifacts. METHODS We developed a high-efficiency spiral in-out bSSFP acquisition, with zeroth- and first-gradient moment nulling, and an EPI bSSFP acquisition for cardiac cine imaging using a contemporary MRI system modified to operate at 0.55T. Spiral in-out and EPI bSSFP cine protocols, with TR = 8 ms, were designed to maintain both spatiotemporal resolution and breath-hold length. Simulations, phantom imaging, and healthy volunteer imaging studies (n = 12) were performed to assess SNR and image quality using these high sampling duty-cycle bSSFP sequences. RESULTS Spiral in-out bSSFP performed favorably at 0.55T and generated good image quality, whereas EPI bSSFP suffered motion and flow artifacts. There was no difference in ejection fraction comparing spiral in-out with standard Cartesian imaging. Moreover, human images demonstrated a 79% ± 21% increase in myocardial SNR using spiral in-out bSSFP and 50% ± 14% increase in SNR using EPI bSSFP as compared with the reference Cartesian acquisition. Spiral in-out acquisitions at 0.55T recovered 69% ± 14% of the myocardial SNR at 1.5T. CONCLUSION Efficient bSSFP spiral in-out provided high-quality cardiac cine imaging and SNR recovery on a high-performance 0.55T MRI system.
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Affiliation(s)
- Matthew C Restivo
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Rajiv Ramasawmy
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - W Patricia Bandettini
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Daniel A Herzka
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Adrienne E Campbell-Washburn
- Cardiovascular Branch, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
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Sivasubramanian M, Chuang YC, Chen NT, Lo LW. Seeing Better and Going Deeper in Cancer Nanotheranostics. Int J Mol Sci 2019; 20:E3490. [PMID: 31315232 PMCID: PMC6678689 DOI: 10.3390/ijms20143490] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 07/12/2019] [Accepted: 07/12/2019] [Indexed: 02/07/2023] Open
Abstract
Biomedical imaging modalities in clinical practice have revolutionized oncology for several decades. State-of-the-art biomedical techniques allow visualizing both normal physiological and pathological architectures of the human body. The use of nanoparticles (NP) as contrast agents enabled visualization of refined contrast images with superior resolution, which assists clinicians in more accurate diagnoses and in planning appropriate therapy. These desirable features are due to the ability of NPs to carry high payloads (contrast agents or drugs), increased in vivo half-life, and disease-specific accumulation. We review the various NP-based interventions for treatments of deep-seated tumors, involving "seeing better" to precisely visualize early diagnosis and "going deeper" to activate selective therapeutics in situ.
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Affiliation(s)
- Maharajan Sivasubramanian
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Zhunan 350, Taiwan
| | - Yao Chen Chuang
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Zhunan 350, Taiwan
| | - Nai-Tzu Chen
- Department of Cosmeceutics, China Medical University, Taichung 40402, Taiwan.
- Department of Biological Science and Technology, China Medical University, Taichung 40402, Taiwan.
| | - Leu-Wei Lo
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Zhunan 350, Taiwan.
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15
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Panman JL, To YY, van der Ende EL, Poos JM, Jiskoot LC, Meeter LHH, Dopper EGP, Bouts MJRJ, van Osch MJP, Rombouts SARB, van Swieten JC, van der Grond J, Papma JM, Hafkemeijer A. Bias Introduced by Multiple Head Coils in MRI Research: An 8 Channel and 32 Channel Coil Comparison. Front Neurosci 2019; 13:729. [PMID: 31379483 PMCID: PMC6648353 DOI: 10.3389/fnins.2019.00729] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 06/28/2019] [Indexed: 12/14/2022] Open
Abstract
Neuroimaging MRI data in scientific research is increasingly pooled, but the reliability of such studies may be hampered by the use of different hardware elements. This might introduce bias, for example when cross-sectional studies pool data acquired with different head coils, or when longitudinal clinical studies change head coils halfway. In the present study, we aimed to estimate this possible bias introduced by using different head coils to create awareness and to avoid misinterpretation of results. We acquired, with both an 8 channel and 32 channel head coil, T1-weighted, diffusion tensor imaging and resting state fMRI images at 3T MRI (Philips Achieva) with stable acquisition parameters in a large group of cognitively healthy participants (n = 77). Standard analysis methods, i.e., voxel-based morphometry, tract-based spatial statistics and resting state functional network analyses, were used in a within-subject design to compare 8 and 32 channel head coil data. Signal-to-noise ratios (SNR) for both head coils showed similar ranges, although the 32 channel SNR profile was more homogeneous. Our data demonstrates specific patterns of gray and white matter volume differences between head coils (relative volume change of 6 to 9%), related to altered image contrast and therefore, altered tissue segmentation. White matter connectivity (fractional anisotropy and diffusivity measures) showed hemispherical dependent differences between head coils (relative connectivity change of 4 to 6%), and functional connectivity in resting state networks was higher using the 32 channel head coil in posterior cortical areas (relative change up to 27.5%). This study shows that, even when acquisition protocols are harmonized, the results of standardized analysis models can be severely affected by the use of different head coils. Researchers should be aware of this when combining multiple neuroimaging MRI datasets, to prevent coil-related bias and avoid misinterpretation of their findings.
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Affiliation(s)
- Jessica L Panman
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Yang Yang To
- Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Emma L van der Ende
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Jackie M Poos
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Lize C Jiskoot
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Lieke H H Meeter
- Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Elise G P Dopper
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Mark J R J Bouts
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Department of Methodology and Statistics, Institute of Psychology, Leiden University, Leiden, Netherlands.,Leiden Institute for Brain and Cognition, Leiden University, Leiden, Netherlands
| | - Matthias J P van Osch
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Leiden Institute for Brain and Cognition, Leiden University, Leiden, Netherlands
| | - Serge A R B Rombouts
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Department of Methodology and Statistics, Institute of Psychology, Leiden University, Leiden, Netherlands.,Leiden Institute for Brain and Cognition, Leiden University, Leiden, Netherlands
| | - John C van Swieten
- Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | | | - Janne M Papma
- Department of Neurology, Erasmus University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Anne Hafkemeijer
- Department of Radiology, Leiden University Medical Center, Leiden, Netherlands.,Department of Methodology and Statistics, Institute of Psychology, Leiden University, Leiden, Netherlands.,Leiden Institute for Brain and Cognition, Leiden University, Leiden, Netherlands
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16
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Tsoukalas C, Geninatti-Crich S, Gaitanis A, Tsotakos T, Paravatou-Petsotas M, Aime S, Jiménez-Juárez R, Anagnostopoulos CD, Djanashvili K, Bouziotis P. Tumor Targeting via Sialic Acid: [ 68Ga]DOTA-en-pba as a New Tool for Molecular Imaging of Cancer with PET. Mol Imaging Biol 2019; 20:798-807. [PMID: 29464496 DOI: 10.1007/s11307-018-1176-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE The aim of this study was to demonstrate the potential of Ga-68-labeled macrocycle (DOTA-en-pba) conjugated with phenylboronic vector for tumor recognition by positron emission tomography (PET), based on targeting of the overexpressed sialic acid (Sia). PROCEDURES The imaging reporter DOTA-en-pba was synthesized and labeled with Ga-68 at high efficiency. Cell binding assay on Mel-C and B16-F10 melanoma cells was used to evaluate melanin production and Sia overexpression to determine the best model for demonstrating the capability of [68Ga]DOTA-en-pba to recognize tumors. The in vivo PET imaging was done with B16-F10 tumor-bearing SCID mice injected with [68Ga]DOTA-en-pba intravenously. Tumor, blood, and urine metabolites were assessed to evaluate the presence of a targeting agent. RESULTS The affinity of [68Ga]DOTA-en-pba to Sia was demonstrated on B16-F10 melanoma cells, after the production of melanin as well as Sia overexpression was proved to be up to four times higher in this cell line compared to that in Mel-C cells. Biodistribution studies in B16-F10 tumor-bearing SCID mice showed blood clearance at the time points studied, while uptake in the tumor peaked at 60 min post-injection (6.36 ± 2.41 % ID/g). The acquired PET images were in accordance with the ex vivo biodistribution results. Metabolite assessment on tumor, blood, and urine samples showed that [68Ga]DOTA-en-pba remains unmetabolized up to at least 60 min post-injection. CONCLUSIONS Our work is the first attempt for in vivo imaging of cancer by targeting overexpression of sialic acid on cancer cells with a radiotracer in PET.
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Affiliation(s)
- Charalambos Tsoukalas
- Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, National Center for Scientific Research "Demokritos", Aghia Paraskevi, 153 10, Athens, Greece
| | - Simonetta Geninatti-Crich
- Department of Molecular Biotechnology and Health Sciences, University of Turin, via Nizza 52, Torino, Italy
| | - Anastasios Gaitanis
- Biomedical Research Foundation of the Academy of Athens, 4 Soranou Ephessiou Street, 115 27, Athens, Greece
| | - Theodoros Tsotakos
- Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, National Center for Scientific Research "Demokritos", Aghia Paraskevi, 153 10, Athens, Greece
| | - Maria Paravatou-Petsotas
- Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, National Center for Scientific Research "Demokritos", Aghia Paraskevi, 153 10, Athens, Greece
| | - Silvio Aime
- Department of Molecular Biotechnology and Health Sciences, University of Turin, via Nizza 52, Torino, Italy
| | - Rogelio Jiménez-Juárez
- Department of Organic Chemistry, National School of Biological Sciences, National Polytechnical Institute, Prolongación de Carpio y Plan de Ayala S/N, 11340, Mexico D.F., Mexico.,Department of Biotechnology, Delft University of Technology, Van der Maasweg, 2629 HZ, Delft, Netherlands
| | | | - Kristina Djanashvili
- Department of Biotechnology, Delft University of Technology, Van der Maasweg, 2629 HZ, Delft, Netherlands
| | - Penelope Bouziotis
- Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, National Center for Scientific Research "Demokritos", Aghia Paraskevi, 153 10, Athens, Greece.
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18
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Wu M, Shu J. Multimodal Molecular Imaging: Current Status and Future Directions. CONTRAST MEDIA & MOLECULAR IMAGING 2018; 2018:1382183. [PMID: 29967571 PMCID: PMC6008764 DOI: 10.1155/2018/1382183] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/11/2018] [Accepted: 05/10/2018] [Indexed: 12/12/2022]
Abstract
Molecular imaging has emerged at the end of the last century as an interdisciplinary method involving in vivo imaging and molecular biology aiming at identifying living biological processes at a cellular and molecular level in a noninvasive manner. It has a profound role in determining disease changes and facilitating drug research and development, thus creating new medical modalities to monitor human health. At present, a variety of different molecular imaging techniques have their advantages, disadvantages, and limitations. In order to overcome these shortcomings, researchers combine two or more detection techniques to create a new imaging mode, such as multimodal molecular imaging, to obtain a better result and more information regarding monitoring, diagnosis, and treatment. In this review, we first describe the classic molecular imaging technology and its key advantages, and then, we offer some of the latest multimodal molecular imaging modes. Finally, we summarize the great challenges, the future development, and the great potential in this field.
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Affiliation(s)
- Min Wu
- Department of Radiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
| | - Jian Shu
- Department of Radiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
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19
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Veersema TJ, Ferrier CH, van Eijsden P, Gosselaar PH, Aronica E, Visser F, Zwanenburg JM, de Kort GAP, Hendrikse J, Luijten PR, Braun KPJ. Seven tesla MRI improves detection of focal cortical dysplasia in patients with refractory focal epilepsy. Epilepsia Open 2017; 2:162-171. [PMID: 29588945 PMCID: PMC5719847 DOI: 10.1002/epi4.12041] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/31/2016] [Indexed: 11/30/2022] Open
Abstract
Objective The aim of this study is to determine whether the use of 7 tesla (T) MRI in clinical practice leads to higher detection rates of focal cortical dysplasias in possible candidates for epilepsy surgery. Methods In our center patients are referred for 7 T MRI if lesional focal epilepsy is suspected, but no abnormalities are detected at one or more previous, sufficient‐quality lower‐field MRI scans, acquired with a dedicated epilepsy protocol, or when concealed pathology is suspected in combination with MR‐visible mesiotemporal sclerosis—dual pathology. We assessed 40 epilepsy patients who underwent 7 T MRI for presurgical evaluation and whose scans (both 7 T and lower field) were discussed during multidisciplinary epilepsy surgery meetings that included a dedicated epilepsy neuroradiologist. We compared the conclusions of the multidisciplinary visual assessments of 7 T and lower‐field MRI scans. Results In our series of 40 patients, multidisciplinary evaluation of 7 T MRI identified additional lesions not seen on lower‐field MRI in 9 patients (23%). These findings were guiding in surgical planning. So far, 6 patients underwent surgery, with histological confirmation of focal cortical dysplasia or mild malformation of cortical development. Significance Seven T MRI improves detection of subtle focal cortical dysplasia and mild malformations of cortical development in patients with intractable epilepsy and may therefore contribute to identification of surgical candidates and complete resection of the epileptogenic lesion, and thus to postoperative seizure freedom.
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Affiliation(s)
- Tim J. Veersema
- Department of Neurology and NeurosurgeryBrain Center Rudolf MagnusUniversity Medical Center UtrechtUtrechtthe Netherlands
| | - Cyrille H. Ferrier
- Department of Neurology and NeurosurgeryBrain Center Rudolf MagnusUniversity Medical Center UtrechtUtrechtthe Netherlands
| | - Pieter van Eijsden
- Department of Neurology and NeurosurgeryBrain Center Rudolf MagnusUniversity Medical Center UtrechtUtrechtthe Netherlands
| | - Peter H. Gosselaar
- Department of Neurology and NeurosurgeryBrain Center Rudolf MagnusUniversity Medical Center UtrechtUtrechtthe Netherlands
| | - Eleonora Aronica
- Department of (Neuro)PathologyAcademic Medical CenterUniversity of AmsterdamAmsterdamthe Netherlands
- Center for NeuroscienceSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamthe Netherlands
- SEIN—Stichting Epilepsie Instellingen NederlandHeemstedethe Netherlands
| | | | - Jaco M. Zwanenburg
- Department of RadiologyUniversity Medical Center UtrechtUtrechtthe Netherlands
| | | | - Jeroen Hendrikse
- Department of RadiologyUniversity Medical Center UtrechtUtrechtthe Netherlands
| | - Peter R. Luijten
- Department of RadiologyUniversity Medical Center UtrechtUtrechtthe Netherlands
| | - Kees P. J. Braun
- Department of Neurology and NeurosurgeryBrain Center Rudolf MagnusUniversity Medical Center UtrechtUtrechtthe Netherlands
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20
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Diagnostic Efficacy of 3-T MRI for Knee Injuries Using Arthroscopy as a Reference Standard: A Meta-Analysis. AJR Am J Roentgenol 2016; 207:369-77. [PMID: 27248283 DOI: 10.2214/ajr.15.15795] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE The objectives of our study were to assess the evidence for the diagnostic efficacy of 3-T MRI for meniscal and anterior cruciate ligament (ACL) injuries in the knee using arthroscopy as the reference standard and to compare these results with the results of a previous meta-analysis assessing 1.5-T MRI. MATERIALS AND METHODS The online Cochrane Library, MEDLINE, and PubMed databases were searched using the following terms: MRI AND ((3 OR three) AND (Tesla OR T)) AND knee AND arthroscopy AND (menisc* OR ligament). Patient demographics, patient characteristics, MRI scanning details, and diagnostic results were investigated. The methodologic quality of the included studies was assessed using the revised Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. A meta-analysis of studies using 3-T MRI was performed, and the results were compared with a previous meta-analysis of studies using 1.5-T MRI. RESULTS One hundred one studies were identified by the search strategy, and 13 studies were included in our review. Twelve studies were considered to have level 1b evidence, and one study was considered to have level 2b evidence. All 13 studies had high methodologic integrity and low risk of bias using the QUADAS-2 tool. The studies included 1197 patients with a mean age of 41.9 years. Ten of the 13 studies were eligible for meta-analysis. The mean sensitivity and mean specificity of 3-T MRI for knee injuries by location were as follows: medial meniscus, 0.94 (95% CI, 0.91-0.96) and 0.79 (95% CI, 0.75-0.83), respectively; lateral meniscus, 0.81 (95% CI, 0.75-0.85) and 0.87 (95% CI, 0.84-0.89); and ACL, 0.92 (95% CI, 0.83-0.96) and 0.99 (95% CI, 0.96-1.00). The specificity of 3-T MRI for injuries of the lateral meniscus was significantly lower than that of 1.5-T MRI (p = 0.0013). CONCLUSION This study does not provide evidence that 3-T scanners have superior diagnostic efficacy for meniscal damage and ACL integrity when compared with previous studies of 1.5-T machines.
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21
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Molecular, Functional, and Structural Imaging of Major Depressive Disorder. Neurosci Bull 2016; 32:273-85. [PMID: 27142698 DOI: 10.1007/s12264-016-0030-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 03/16/2016] [Indexed: 12/31/2022] Open
Abstract
Major depressive disorder (MDD) is a significant cause of morbidity and mortality worldwide, correlating with genetic susceptibility and environmental risk factors. Molecular, functional, and structural imaging approaches have been increasingly used to detect neurobiological changes, analyze neurochemical correlates, and parse pathophysiological mechanisms underlying MDD. We reviewed recent neuroimaging publications on MDD in terms of molecular, functional, and structural alterations as detected mainly by magnetic resonance imaging (MRI) and positron emission tomography. Altered structure and function of brain regions involved in the cognitive control of affective state have been demonstrated. An abnormal default mode network, as revealed by resting-state functional MRI, is likely associated with aberrant metabolic and serotonergic function revealed by radionuclide imaging. Further multi-modal investigations are essential to clarify the characteristics of the cortical network and serotonergic system associated with behavioral and genetic variations in MDD.
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22
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Lucano E, Liberti M, Mendoza GG, Lloyd T, Iacono MI, Apollonio F, Wedan S, Kainz W, Angelone LM. Assessing the Electromagnetic Fields Generated By a Radiofrequency MRI Body Coil at 64 MHz: Defeaturing Versus Accuracy. IEEE Trans Biomed Eng 2015; 63:1591-1601. [PMID: 26685220 DOI: 10.1109/tbme.2015.2506680] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
UNLABELLED GOAL This study aims at a systematic assessment of five computational models of a birdcage coil for magnetic resonance imaging (MRI) with respect to accuracy and computational cost. METHODS The models were implemented using the same geometrical model and numerical algorithm, but different driving methods (i.e., coil "defeaturing"). The defeatured models were labeled as: specific (S2), generic (G32, G16), and hybrid (H16, [Formula: see text]). The accuracy of the models was evaluated using the "symmetric mean absolute percentage error" ("SMAPE"), by comparison with measurements in terms of frequency response, as well as electric ( ||→E||) and magnetic ( || →B ||) field magnitude. RESULTS All the models computed the || →B || within 35% of the measurements, only the S2, G32, and H16 were able to accurately model the ||→E|| inside the phantom with a maximum SMAPE of 16%. Outside the phantom, only the S2 showed a SMAPE lower than 11%. CONCLUSIONS Results showed that assessing the accuracy of || →B || based only on comparison along the central longitudinal line of the coil can be misleading. Generic or hybrid coils - when properly modeling the currents along the rings/rungs - were sufficient to accurately reproduce the fields inside a phantom while a specific model was needed to accurately model ||→E|| in the space between coil and phantom. SIGNIFICANCE Computational modeling of birdcage body coils is extensively used in the evaluation of radiofrequency-induced heating during MRI. Experimental validation of numerical models is needed to determine if a model is an accurate representation of a physical coil.
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Affiliation(s)
| | | | | | - Tom Lloyd
- Imricor Medical Systems, Burnsville, MN, USA
| | | | | | - Steve Wedan
- Imricor Medical Systems, Burnsville, MN, USA
| | - Wolfgang Kainz
- Office of Science and Engineering Laboratories, U.S. FDA, CDRH
| | - Leonardo M Angelone
- Office of Science and Engineering Laboratories, U.S. FDA, CDRH, Silver Spring, MD, USA
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Solis-Najera SE, Martin R, Vazquez F, Rodriguez AO. Surface coil with reduced specific absorption rate for rat MRI at 7 T. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2015; 28:599-608. [PMID: 26449714 DOI: 10.1007/s10334-015-0501-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 09/06/2015] [Accepted: 09/15/2015] [Indexed: 12/23/2022]
Abstract
OBJECTIVE A scaled-down slotted surface radio frequency (RF) coil was built, and the specific absorbance rate (SAR) in 100 mg of tissue (SAR100 mg) produced in a rat brain phantom was computed at 7 T. MATERIALS AND METHODS A slotted coil 2-cm in diameter with six circular slots was developed. Its theoretical and experimental performance was computed and compared using the signal-to-noise ratio (SNR) expression and phantom images obtained with a spin echo sequence. Electromagnetic simulations were performed using the finite integral method with saline sphere and rat brain phantoms. SAR100 mg was computed for the circular coil, by varying its radius, and was also computed for the slotted coil. RESULTS The slotted coil quality factor gave a twofold increment over the circular coil, and noise was reduced by 17%. The experimental SNR of the slotted coil produced a 30% improvement for points near the coil plane. The theoretical and experimental results showed substantial agreement. Axial map histograms and profiles showed greater SAR100 mg values for the circular coil than for the slotted coil. CONCLUSIONS The slotted surface coil offers improved performance and low SAR100 mg for rat brain imaging at 7 T. This approach may be used with new RF coils to investigate SAR in humans.
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Affiliation(s)
- Sergio E Solis-Najera
- Department of Physics, Faculty of Sciences, Universidad Nacional Autonoma de Mexico, 04510, Mexico, D.F., Mexico
| | - Rodrigo Martin
- Department of Physics, Faculty of Sciences, Universidad Nacional Autonoma de Mexico, 04510, Mexico, D.F., Mexico
- Department of Electrical Engineering, Universidad Autonoma Metropolitana Iztapalapa, 09340, Mexico, D.F., Mexico
| | - Fabian Vazquez
- Department of Physics, Faculty of Sciences, Universidad Nacional Autonoma de Mexico, 04510, Mexico, D.F., Mexico
| | - Alfredo O Rodriguez
- Department of Electrical Engineering, Universidad Autonoma Metropolitana Iztapalapa, 09340, Mexico, D.F., Mexico.
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McDonald RJ, Schwartz KM, Eckel LJ, Diehn FE, Hunt CH, Bartholmai BJ, Erickson BJ, Kallmes DF. The effects of changes in utilization and technological advancements of cross-sectional imaging on radiologist workload. Acad Radiol 2015. [PMID: 26210525 DOI: 10.1016/j.acra.2015.05.007] [Citation(s) in RCA: 224] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
RATIONALE AND OBJECTIVES To examine the effect of changes in utilization and advances in cross-sectional imaging on radiologists' workload. MATERIALS AND METHODS All computed tomography (CT) and magnetic resonance imaging (MRI) examinations performed at a single institution between 1999 and 2010 were identified and associated with the total number of images for each examination. Annual trends in institutional numbers of interpreted examinations and images were translated to changes in daily workload for the individual radiologist by normalizing to the number of dedicated daily CT and MRI work assignments, assuming a 255-day/8-hour work day schedule. Temporal changes in institutional and individual workload were assessed by Sen's slope analysis (Q = median slope) and Mann-Kendall test (Z = Z statistic). RESULTS From 1999 to 2010, a total of 1,517,149 cross-sectional imaging studies (CT = 994,471; MRI = 522,678) comprising 539,210,581 images (CT = 339,830,947; MRI = 199,379,634) were evaluated at our institution. Total annual cross-sectional studies steadily increased from 84,409 in 1999 to 147,336 in 2010, representing a twofold increase in workload (Q = 6465/year, Z = 4.2, P < .0001). Concomitantly, the number of annual departmental cross-sectional images interpreted increased from 9,294,140 in 1990 to 94,271,551 in 2010, representing a 10-fold increase (Q = 8707876/year, Z = 4.5, P < .0001). Adjusting for staffing changes, the number of images requiring interpretation per minute of every workday per staff radiologist increased from 2.9 in 1999 to 16.1 in 2010 (Q = 1.7/year, Z = 4.3, P < .0001). CONCLUSIONS Imaging volumes have grown at a disproportionate rate to imaging utilization increases at our institution. The average radiologist interpreting CT or MRI examinations must now interpret one image every 3-4 seconds in an 8-hour workday to meet workload demands.
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Moftakhar P, Lillaney P, Losey AD, Cooke DL, Martin AJ, Thorne BRH, Arenson RL, Saeed M, Wilson MW, Hetts SW. New-Generation Laser-lithographed Dual-Axis Magnetically Assisted Remote-controlled Endovascular Catheter for Interventional MR Imaging: In Vitro Multiplanar Navigation at 1.5 T and 3 T versus X-ray Fluoroscopy. Radiology 2015; 277:842-52. [PMID: 26030659 DOI: 10.1148/radiol.2015142648] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
PURPOSE To assess the feasibility of multiplanar vascular navigation with a new magnetically assisted remote-controlled (MARC) catheter with real-time magnetic resonance (MR) imaging at 1.5 T and 3 T and to compare it with standard x-ray guidance in simulated endovascular catheterization procedures. MATERIALS AND METHODS A 1.6-mm-diameter custom clinical-grade microcatheter prototype with lithographed double-saddle coils at the distal tip was deflected with real-time MR imaging. Two inexperienced operators and two experienced operators catheterized anteroposterior (celiac, superior mesenteric, and inferior mesenteric arteries) and mediolateral (renal arteries) branch vessels in a cryogel abdominal aortic phantom. This was repeated with conventional x-ray fluoroscopy by using clinical catheters and guidewires. Mean procedure times and percentage success data were analyzed with linear mixed-effects regression. RESULTS The MARC catheter tip was visible at 1.5 T and 3 T. Among inexperienced operators, MARC MR imaging guidance was not statistically different from x-ray guidance at 1.5 T (67% successful vessel selection turns with MR imaging vs 76% with x-ray guidance, P = .157) and at 3 T (75% successful turns with MR imaging vs 76% with x-ray guidance, P = .869). Experienced operators were more successful in catheterizing vessels with x-ray guidance (98% success within 60 seconds) than with 1.5-T (65%, P < .001) or 3-T (75%) MR imaging. Among inexperienced operators, mean procedure time was nearly equivalent by using MR imaging (31 seconds) and x-ray guidance (34 seconds, P = .436). Among experienced operators, catheterization was faster with x-ray guidance (20 seconds) compared with 1.5-T MR imaging (42 seconds, P < .001), but MARC guidance improved at 3 T (31 seconds). MARC MR imaging guidance at 3 T was not significantly different from x-ray guidance for the celiac (P = .755), superior mesenteric (P = .358), and inferior mesenteric (P = .065) arteries. CONCLUSION Multiplanar navigation with a new MARC catheter with real-time MR imaging at 1.5 T and 3 T is feasible and comparable to x-ray guidance for anteroposterior vessels at 3 T in a vascular phantom.
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Affiliation(s)
- Parham Moftakhar
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Prasheel Lillaney
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Aaron D Losey
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Daniel L Cooke
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Alastair J Martin
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Bradford R H Thorne
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Ronald L Arenson
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Maythem Saeed
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Mark W Wilson
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
| | - Steven W Hetts
- From the Department of Radiology and Biomedical Imaging, University of California-San Francisco, 505 Parnassus Ave, L-352, San Francisco, CA 94143-0628
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26
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Garg B, Sung CH, Ling YC. Graphene-based nanomaterials as molecular imaging agents. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2015; 7:737-58. [PMID: 25857851 DOI: 10.1002/wnan.1342] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 02/15/2015] [Accepted: 02/17/2015] [Indexed: 12/12/2022]
Abstract
Molecular imaging (MI) is a noninvasive, real-time visualization of biochemical events at the cellular and molecular level within tissues, living cells, and/or intact objects that can be advantageously applied in the areas of diagnostics, therapeutics, drug discovery, and development in understanding the nanoscale reactions including enzymatic conversions and protein-protein interactions. Consequently, over the years, great advancement has been made in the development of a variety of MI agents such as peptides, aptamers, antibodies, and various nanomaterials (NMs) including single-walled carbon nanotubes. Recently, graphene, a material popularized by Geim & Novoselov, has ignited considerable research efforts to rationally design and execute a wide range of graphene-based NMs making them an attractive platform for developing highly sensitive MI agents. Owing to their exceptional physicochemical and biological properties combined with desirable surface engineering, graphene-based NMs offer stable and tunable visible emission, small hydrodynamic size, low toxicity, and high biocompatibility and thus have been explored for in vitro and in vivo imaging applications as a promising alternative of traditional imaging agents. This review begins by describing the intrinsic properties of graphene and the key MI modalities. After which, we provide an overview on the recent advances in the design and development as well as physicochemical properties of the different classes of graphene-based NMs (graphene-dye conjugates, graphene-antibody conjugates, graphene-nanoparticle composites, and graphene quantum dots) being used as MI agents for potential applications including theranostics. Finally, the major challenges and future directions in the field will be discussed.
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Affiliation(s)
- Bhaskar Garg
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - Chu-Hsun Sung
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - Yong-Chien Ling
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
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27
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Molecular and functional imaging of internet addiction. BIOMED RESEARCH INTERNATIONAL 2015; 2015:378675. [PMID: 25879023 PMCID: PMC4388011 DOI: 10.1155/2015/378675] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 10/08/2014] [Indexed: 12/16/2022]
Abstract
Maladaptive use of the Internet results in Internet addiction (IA), which is associated with various negative consequences. Molecular and functional imaging techniques have been increasingly used for analysis of neurobiological changes and neurochemical correlates of IA. This review summarizes molecular and functional imaging findings on neurobiological mechanisms of IA, focusing on magnetic resonance imaging (MRI) and nuclear imaging modalities including positron emission tomography (PET) and single photon emission computed tomography (SPECT). MRI studies demonstrate that structural changes in frontal cortex are associated with functional abnormalities in Internet addicted subjects. Nuclear imaging findings indicate that IA is associated with dysfunction of the brain dopaminergic systems. Abnormal dopamine regulation of the prefrontal cortex (PFC) could underlie the enhanced motivational value and uncontrolled behavior over Internet overuse in addicted subjects. Further investigations are needed to determine specific changes in the Internet addictive brain, as well as their implications for behavior and cognition.
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28
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Deborah AH, Karima S. Hemodynamic imaging of the auditory cortex. HANDBOOK OF CLINICAL NEUROLOGY 2015; 129:257-75. [PMID: 25726274 DOI: 10.1016/b978-0-444-62630-1.00015-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Over the past 20 years or so, functional magnetic resonance imaging (fMRI) has proven to be an influential tool for measuring perceptual and cognitive processing non-invasively in the human brain. This article provides a brief yet comprehensive overview of this dominant method for human auditory neuroscience, providing the reader with knowledge about the practicalities of using this technique to assess central auditory coding. Key learning objectives include developing an understanding of the basic MR physics underpinning the technique, the advantage of auditory fMRI over other current neuroimaging alternatives, and highlighting some of the practical considerations involved in setting up, running, and analyzing an auditory fMRI experiment. The future utility of fMRI and anticipated technical developments is also briefly evaluated. Throughout the review, key concepts are illustrated using specific author examples, with particular emphasis on fMRI findings that address questions pertaining to basic sound coding (such as frequency and pitch).
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Affiliation(s)
- Ann Hall Deborah
- National Institute for Health Research, Nottingham Hearing Biomedical Research Unit, University of Nottingham, Nottingham, UK.
| | - Susi Karima
- Division of Psychology, School of Social Sciences, Nottingham Trent University, Nottingham, UK
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29
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Zeng W, Wang X, Xu P, Liu G, Eden HS, Chen X. Molecular imaging of apoptosis: from micro to macro. Theranostics 2015; 5:559-82. [PMID: 25825597 PMCID: PMC4377726 DOI: 10.7150/thno.11548] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 02/18/2015] [Indexed: 12/21/2022] Open
Abstract
Apoptosis, or programmed cell death, is involved in numerous human conditions including neurodegenerative diseases, ischemic damage, autoimmune disorders and many types of cancer, and is often confused with other types of cell death. Therefore strategies that enable visualized detection of apoptosis would be of enormous benefit in the clinic for diagnosis, patient management, and development of new therapies. In recent years, improved understanding of the apoptotic machinery and progress in imaging modalities have provided opportunities for researchers to formulate microscopic and macroscopic imaging strategies based on well-defined molecular markers and/or physiological features. Correspondingly, a large collection of apoptosis imaging probes and approaches have been documented in preclinical and clinical studies. In this review, we mainly discuss microscopic imaging assays and macroscopic imaging probes, ranging in complexity from simple attachments of reporter moieties to proteins that interact with apoptotic biomarkers, to rationally designed probes that target biochemical changes. Their clinical translation will also be our focus.
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30
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Vandenberghe S, Marsden PK. PET-MRI: a review of challenges and solutions in the development of integrated multimodality imaging. Phys Med Biol 2015; 60:R115-54. [PMID: 25650582 DOI: 10.1088/0031-9155/60/4/r115] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The integration of positron emission tomography (PET) and magnetic resonance imaging (MRI) has been an ongoing research topic for the last 20 years. This paper gives an overview of the different developments and the technical problems associated with combining PET and MRI in one system. After explaining the different detector concepts for integrating PET-MRI and minimising interference the limitations and advantages of different solutions for the detector and system are described for preclinical and clinical imaging systems. The different integrated PET-MRI systems are described in detail. Besides detector concepts and system integration the challenges and proposed solutions for attenuation correction and the potential for motion correction and resolution recovery are also discussed in this topical review.
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Affiliation(s)
- Stefaan Vandenberghe
- Department of Electronics and Information Systems, MEDISIP, Ghent University-iMinds Medical IT-IBiTech, De Pintelaan 185 block B, B-9000 Ghent, Belgium
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31
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Edelman RR. The history of MR imaging as seen through the pages of radiology. Radiology 2015; 273:S181-200. [PMID: 25340436 DOI: 10.1148/radiol.14140706] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The first reports in Radiology pertaining to magnetic resonance (MR) imaging were published in 1980, 7 years after Paul Lauterbur pioneered the first MR images and 9 years after the first human computed tomographic images were obtained. Historical advances in the research and clinical applications of MR imaging very much parallel the remarkable advances in MR imaging technology. These advances can be roughly classified into hardware (eg, magnets, gradients, radiofrequency [RF] coils, RF transmitter and receiver, MR imaging-compatible biopsy devices) and imaging techniques (eg, pulse sequences, parallel imaging, and so forth). Image quality has been dramatically improved with the introduction of high-field-strength superconducting magnets, digital RF systems, and phased-array coils. Hybrid systems, such as MR/positron emission tomography (PET), combine the superb anatomic and functional imaging capabilities of MR imaging with the unsurpassed capability of PET to demonstrate tissue metabolism. Supported by the improvements in hardware, advances in pulse sequence design and image reconstruction techniques have spurred dramatic improvements in imaging speed and the capability for studying tissue function. In this historical review, the history of MR imaging technology and developing research and clinical applications, as seen through the pages of Radiology, will be considered.
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Affiliation(s)
- Robert R Edelman
- From the Department of Radiology, NorthShore University HealthSystem, 2650 Ridge Ave, Evanston, IL 60201
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32
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McKeon KE, Wright BT, Lee DH. Accuracy of MRI-based Diagnoses for Distal Upper Extremity Soft Tissue Masses. J Hand Microsurg 2015; 7:61-6. [PMID: 26078505 DOI: 10.1007/s12593-015-0174-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 01/05/2015] [Indexed: 01/03/2023] Open
Abstract
UNLABELLED To determine the accuracy of the pre-operative MRI-based diagnosis of soft tissue masses in the forearm, wrist, and hand, the records of 144 patients who underwent an MRI followed by excision of a soft tissue mass in the forearm, wrist, or hand were reviewed. The MRI-based diagnosis was compared to the histological diagnosis, which was considered the gold standard. The sensitivity, specificity, positive predictive value, and negative predictive value of the MRI-based diagnosis were calculated. A multivariate regression analysis was performed.While the accuracy of the MRI-based diagnosis varied widely, there was an overall sensitivity of 75 %. The most accurate diagnosis was an MRI-based diagnosis of ganglion cyst, which had a sensitivity of 94.7 % and a specificity of 94.4 %. Of particular concern was that the MRI-based diagnosis of a malignancy was only 66.7 % sensitive, with a positive predictive value of 44.4 %. On multivariate regression analysis, there was a trend towards improved accuracy in the wrist when compared to the finger, although this did not reach statistical significance.While pre-operative MRI remains a valuable tool for the evaluation of soft tissue masses in the distal upper extremity, caution is warranted when basing the diagnosis on MRI evidence alone. LEVEL OF EVIDENCE Level IV/Diagnostic.
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Affiliation(s)
- Kathleen E McKeon
- Andrews Sports Medicine and Orthopaedic Center, 805 St. Vincent's Drive, Ste. 100, Birmingham, AL 35205 USA
| | - Brian T Wright
- Vanderbilt School of Medicine, 1161 21st Avenue South, Ste. T1217, Nashville, TN 37232 USA
| | - Donald H Lee
- Vanderbilt Orthopaedic Institute, Vanderbilt University Medical Center, 1215 21st Avenue South, Ste. 3200, Nashville, TN 37232 USA
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33
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Kölmel DK, Nieger M, Bräse S. Highly efficient synthesis of polyfluorinated dendrons suitable for click chemistry. RSC Adv 2015. [DOI: 10.1039/c5ra02804c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new and efficient access to C2v-symmetric dendrons with up to 72 magnetically equivalent fluorine atoms is presented. Those dendrons are well suited to act as potential 19F MRI probes.
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Affiliation(s)
- Dominik K. Kölmel
- Karlsruhe Institute of Technology (KIT)
- Institute of Organic Chemistry
- 76131 Karlsruhe
- Germany
| | - Martin Nieger
- University of Helsinki
- Laboratory of Inorganic Chemistry
- Finland
| | - Stefan Bräse
- Karlsruhe Institute of Technology (KIT)
- Institute of Organic Chemistry
- 76131 Karlsruhe
- Germany
- Karlsruhe Institute of Technology (KIT)
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34
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Perera V, Yang LD, Hao J, Chen G, Erokwu BO, Flask CA, Zavalij P, Basilion JP, Huang SD. Biocompatible nanoparticles of KGd(H₂O)₂[Fe(CN)₆]·H₂O with extremely high T₁-weighted relaxivity owing to two water molecules directly bound to the Gd(III) center. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:12018-26. [PMID: 25238130 PMCID: PMC4196746 DOI: 10.1021/la501985p] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 09/18/2014] [Indexed: 05/09/2023]
Abstract
A simple one-step method for preparing biocompatible nanoparticles of gadolinium ferrocyanide coordination polymer KGd(H2O)2[Fe(CN)6]·H2O is reported. The crystal structure of this coordination polymer is determined by X-ray powder diffraction using the bulk materials. The stability, cytotoxicity, cellular uptake, and MR phantom and cellular imaging studies suggest that this coordination-polymer structural platform offers a unique opportunity for developing the next generation of T1-weighted contrast agents with high relaxivity as cellular MR probes for biological receptors or markers. Such high-relaxivity MR probes may hold potential in the study of molecular events and may be used for in vivo MR imaging in biomedical research and clinical applications.
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Affiliation(s)
- Vindya
S. Perera
- Department of Chemistry
and Biochemistry, Kent State University, Kent, Ohio 44240, United States
| | - Liu D. Yang
- Department of Chemistry
and Biochemistry, Kent State University, Kent, Ohio 44240, United States
| | - Jihua Hao
- Case Center for Imaging Research, Department of Radiology, NFCR for Molecular Imaging, Department of Biomedical
Engineering, and Department of Pediatrics, Case Western
Reserve University, Cleveland, Ohio 44106, United States
| | - Guojun Chen
- Department of Chemistry
and Biochemistry, Kent State University, Kent, Ohio 44240, United States
| | - Bernadette O. Erokwu
- Case Center for Imaging Research, Department of Radiology, NFCR for Molecular Imaging, Department of Biomedical
Engineering, and Department of Pediatrics, Case Western
Reserve University, Cleveland, Ohio 44106, United States
| | - Chris A. Flask
- Case Center for Imaging Research, Department of Radiology, NFCR for Molecular Imaging, Department of Biomedical
Engineering, and Department of Pediatrics, Case Western
Reserve University, Cleveland, Ohio 44106, United States
| | - Peter
Y. Zavalij
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - James P. Basilion
- Case Center for Imaging Research, Department of Radiology, NFCR for Molecular Imaging, Department of Biomedical
Engineering, and Department of Pediatrics, Case Western
Reserve University, Cleveland, Ohio 44106, United States
| | - Songping D. Huang
- Department of Chemistry
and Biochemistry, Kent State University, Kent, Ohio 44240, United States
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35
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Tan K, Yoong P, Toms AP. Normal anatomical variants of the menisci and cruciate ligaments that may mimic disease. Clin Radiol 2014; 69:1178-85. [PMID: 25060935 DOI: 10.1016/j.crad.2014.06.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Revised: 06/06/2014] [Accepted: 06/16/2014] [Indexed: 11/30/2022]
Abstract
There are many normal anatomical variants of the knee joint. Some are common and others are rare. With continuing improvements in the spatial resolution of MRI, smaller variants are more clearly demonstrated and can be mistaken for disease. They can all be differentiated from pathological conditions by understanding their anatomy and key differentiating features. This review compares normal variants of the menisci and cruciate ligaments with the pathological disorders that can mimic them.
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Affiliation(s)
- K Tan
- Department of Radiology, Norfolk and Norwich University Hospital, Colney Lane, Norwich NR4 7UY, UK.
| | - P Yoong
- Department of Radiology, Royal Berkshire Hospital, London Road, Reading RG1 5AN, UK
| | - A P Toms
- Department of Radiology, Norfolk and Norwich University Hospital, Colney Lane, Norwich NR4 7UY, UK
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36
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Zeng Z, Parekh P, Li Z, Shi ZZ, Tung CH, Zu Y. Specific and sensitive tumor imaging using biostable oligonucleotide aptamer probes. Am J Cancer Res 2014; 4:945-52. [PMID: 25057318 PMCID: PMC4107294 DOI: 10.7150/thno.9246] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/29/2014] [Indexed: 12/20/2022] Open
Abstract
Although several imaging modalities are widely used for tumor imaging, none are tumor type-specific. Different types of cancer exhibit differential therapeutic responses, thus necessitating development of an imaging modality able to detect various tumor types with high specificity. To illustrate this point, CD30-specific oligonucleotide aptamer in vivo imaging probes were conjugated to the near-infrared IRD800CW reporter. Mice bearing xenografted CD30-positive or control CD30-negative lymphoma tumors on contralateral sides of the same mouse were developed. Following a systemic administration of aptamer probes, whole body imaging of tumor-bearing mice was performed. Imaging signal from tumor sites was analyzed and imaging specificity confirmed by tissue immunostaining. The in vivo biodistribution of aptamer probes was also evaluated. Whole body scans revealed that the RNA-based aptamer probes selectively highlighted CD30-expressing lymphoma tumors immediately after systemic administration, but did not react with control tumors in the same mouse. The resultant imaging signal lasted up to 1 hr and the aptamer probes were rapidly eliminated from the body through urinary and lower intestinal tracts. For more sensitive imaging, biostable CD30-specific ssDNA-based aptamer probes were also generated. Systemic administration of these probes also selectively highlighted the CD30-positive lymphoma tumors, with imaging signal detected 4-5 folds higher than that derived from control tumors in the same animal, and lasted for up to 24hr. This study demonstrates that oligonucleotide aptamer probes can provide tumor type-specific imaging with high sensitivity and a long-lasting signal, indicating their potential for clinical applications.
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37
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Abstract
Since the introduction of 4 T human systems in three academic laboratories circa 1990, rapid progress in imaging and spectroscopy studies in humans at 4 T and animal model systems at 9.4 T have led to the introduction of 7 T and higher magnetic fields for human investigation at about the turn of the century. Work conducted on these platforms has demonstrated the existence of significant advantages in SNR and biological information content at these ultrahigh fields, as well as the presence of numerous challenges. Primary difference from lower fields is the deviation from the near field regime; at the frequencies corresponding to hydrogen resonance conditions at ultrahigh fields, the RF is characterized by attenuated traveling waves in the human body, which leads to image nonuniformities for a given sample-coil configuration because of interferences. These nonuniformities were considered detrimental to the progress of imaging at high field strengths. However, they are advantageous for parallel imaging for signal reception and parallel transmission, two critical technologies that account, to a large extend, for the success of ultrahigh fields. With these technologies, and improvements in instrumentation and imaging methods, ultrahigh fields have provided unprecedented gains in imaging of brain function and anatomy, and started to make inroads into investigation of the human torso and extremities. As extensive as they are, these gains still constitute a prelude to what is to come given the increasingly larger effort committed to ultrahigh field research and development of ever better instrumentation and techniques.
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38
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Magnetic Resonance Imaging: An Accurate, Radiation-Free, Alternative to Computed Tomography for the Primary Imaging and Three-Dimensional Reconstruction of the Bony Orbit. J Oral Maxillofac Surg 2014; 72:611-8. [DOI: 10.1016/j.joms.2013.08.030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 08/26/2013] [Accepted: 08/26/2013] [Indexed: 11/30/2022]
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39
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New researches and application progress of commonly used optical molecular imaging technology. BIOMED RESEARCH INTERNATIONAL 2014; 2014:429198. [PMID: 24696850 PMCID: PMC3947735 DOI: 10.1155/2014/429198] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Accepted: 12/20/2013] [Indexed: 12/26/2022]
Abstract
Optical molecular imaging, a new medical imaging technique, is developed based on genomics, proteomics and modern optical imaging technique, characterized by non-invasiveness, non-radiativity, high cost-effectiveness, high resolution, high sensitivity and simple operation in comparison with conventional imaging modalities. Currently, it has become one of the most widely used molecular imaging techniques and has been applied in gene expression regulation and activity detection, biological development and cytological detection, drug research and development, pathogenesis research, pharmaceutical effect evaluation and therapeutic effect evaluation, and so forth, This paper will review the latest researches and application progresses of commonly used optical molecular imaging techniques such as bioluminescence imaging and fluorescence molecular imaging.
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40
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Chen ZY, Wang YX, Lin Y, Zhang JS, Yang F, Zhou QL, Liao YY. Advance of molecular imaging technology and targeted imaging agent in imaging and therapy. BIOMED RESEARCH INTERNATIONAL 2014; 2014:819324. [PMID: 24689058 PMCID: PMC3943245 DOI: 10.1155/2014/819324] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Revised: 12/29/2013] [Accepted: 12/30/2013] [Indexed: 02/06/2023]
Abstract
Molecular imaging is an emerging field that integrates advanced imaging technology with cellular and molecular biology. It can realize noninvasive and real time visualization, measurement of physiological or pathological process in the living organism at the cellular and molecular level, providing an effective method of information acquiring for diagnosis, therapy, and drug development and evaluating treatment of efficacy. Molecular imaging requires high resolution and high sensitive instruments and specific imaging agents that link the imaging signal with molecular event. Recently, the application of new emerging chemical technology and nanotechnology has stimulated the development of imaging agents. Nanoparticles modified with small molecule, peptide, antibody, and aptamer have been extensively applied for preclinical studies. Therapeutic drug or gene is incorporated into nanoparticles to construct multifunctional imaging agents which allow for theranostic applications. In this review, we will discuss the characteristics of molecular imaging, the novel imaging agent including targeted imaging agent and multifunctional imaging agent, as well as cite some examples of their application in molecular imaging and therapy.
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Affiliation(s)
- Zhi-Yi Chen
- Department of Ultrasound Medicine, Laboratory of Ultrasound Molecular Imaging, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, China
| | - Yi-Xiang Wang
- Department of Imaging and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong
| | - Yan Lin
- Department of Ultrasound Medicine, Laboratory of Ultrasound Molecular Imaging, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, China
| | - Jin-Shan Zhang
- Department of Nuclear Medicine, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, China
| | - Feng Yang
- Department of Ultrasound Medicine, Laboratory of Ultrasound Molecular Imaging, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, China
| | - Qiu-Lan Zhou
- Department of Ultrasound Medicine, Laboratory of Ultrasound Molecular Imaging, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, China
| | - Yang-Ying Liao
- Department of Ultrasound Medicine, Laboratory of Ultrasound Molecular Imaging, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou 510150, China
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41
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42
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Fanourgiakis J, Kanoupakis E. Cardiac rhythm management devices in a magnetic resonance environment. Expert Rev Med Devices 2014; 11:199-203. [PMID: 24471520 DOI: 10.1586/17434440.2014.882228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
MRI is the gold standard diagnostic tool for soft tissue imaging for many specialties. An impressive body of research has proven the effectiveness of cardiac rhythm management devices (CRMDs) objectively, in terms of parameters that include patient's quality of life, morbidity, and mortality. However, interaction between CRMDs and MRI scanners is a problem. Static main magnetic field, radiofrequency energy and the gradient magnetic field are three distinct mechanisms related to MRI and cause risks to CRMDs. Very often, patients with CRMDs have been excluded from undergoing MRI scans despite the fact that these scans were critical for the diagnosis and therapy of patients with serious medical conditions. In order for all patients with CRMDs to have the ability to perform this exam, the industry works hard to design devices that are MRI conditional.
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43
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Kraff O, Fischer A, Nagel AM, Mönninghoff C, Ladd ME. MRI at 7 Tesla and above: demonstrated and potential capabilities. J Magn Reson Imaging 2014; 41:13-33. [PMID: 24478137 DOI: 10.1002/jmri.24573] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 01/03/2014] [Indexed: 12/29/2022] Open
Abstract
With more than 40 installed MR systems worldwide operating at 7 Tesla or higher, ultra-high-field (UHF) imaging has been established as a platform for clinically oriented research in recent years. Along with technical developments that, in part, have also been successfully transferred to lower field strengths, MR imaging and spectroscopy at UHF have demonstrated capabilities and potentials for clinical diagnostics in a variety of studies. In terms of applications, this overview article focuses on already achieved advantages for in vivo imaging, i.e., in imaging the brain and joints of the musculoskeletal system, but also considers developments in body imaging, which is particularly challenging. Furthermore, new applications for clinical diagnostics such as X-nuclei imaging and spectroscopy, which only really become feasible at ultra-high magnetic fields, will be presented.
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Affiliation(s)
- Oliver Kraff
- Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, Essen, Germany
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44
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Skouras S, Gray M, Critchley H, Koelsch S. FMRI scanner noise interaction with affective neural processes. PLoS One 2013; 8:e80564. [PMID: 24260420 PMCID: PMC3832369 DOI: 10.1371/journal.pone.0080564] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 10/04/2013] [Indexed: 11/19/2022] Open
Abstract
The purpose of the present study was the investigation of interaction effects between functional MRI scanner noise and affective neural processes. Stimuli comprised of psychoacoustically balanced musical pieces, expressing three different emotions (fear, neutral, joy). Participants (N=34, 19 female) were split into two groups, one subjected to continuous scanning and another subjected to sparse temporal scanning that features decreased scanner noise. Tests for interaction effects between scanning group (sparse/quieter vs continuous/noisier) and emotion (fear, neutral, joy) were performed. Results revealed interactions between the affective expression of stimuli and scanning group localized in bilateral auditory cortex, insula and visual cortex (calcarine sulcus). Post-hoc comparisons revealed that during sparse scanning, but not during continuous scanning, BOLD signals were significantly stronger for joy than for fear, as well as stronger for fear than for neutral in bilateral auditory cortex. During continuous scanning, but not during sparse scanning, BOLD signals were significantly stronger for joy than for neutral in the left auditory cortex and for joy than for fear in the calcarine sulcus. To the authors' knowledge, this is the first study to show a statistical interaction effect between scanner noise and affective processes and extends evidence suggesting scanner noise to be an important factor in functional MRI research that can affect and distort affective brain processes.
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Affiliation(s)
- Stavros Skouras
- Cluster of Excellence “Languages of Emotion”, Freie Universität Berlin, Berlin, Germany
- Department of Psychology, University of Sussex, Falmer, East Sussex, United Kingdom
| | - Marcus Gray
- Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, East Sussex, United Kingdom
- Centre for Advanced Imaging, University of Queensland, St Lucia, Queensland, Australia
| | - Hugo Critchley
- Clinical Imaging Sciences Centre, Brighton and Sussex Medical School, Brighton, East Sussex, United Kingdom
- Sackler Centre for Consciousness Science, University of Sussex, East Sussex, United Kingdom
| | - Stefan Koelsch
- Cluster of Excellence “Languages of Emotion”, Freie Universität Berlin, Berlin, Germany
- Department of Psychology, University of Sussex, Falmer, East Sussex, United Kingdom
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Zhu D, Liu F, Ma L, Liu D, Wang Z. Nanoparticle-based systems for T(1)-weighted magnetic resonance imaging contrast agents. Int J Mol Sci 2013; 14:10591-607. [PMID: 23698781 PMCID: PMC3676856 DOI: 10.3390/ijms140510591] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 05/09/2013] [Accepted: 05/13/2013] [Indexed: 12/29/2022] Open
Abstract
Because magnetic resonance imaging (MRI) contrast agents play a vital role in diagnosing diseases, demand for new MRI contrast agents, with an enhanced sensitivity and advanced functionalities, is very high. During the past decade, various inorganic nanoparticles have been used as MRI contrast agents due to their unique properties, such as large surface area, easy surface functionalization, excellent contrasting effect, and other size-dependent properties. This review provides an overview of recent progress in the development of nanoparticle-based T1-weighted MRI contrast agents. The chemical synthesis of the nanoparticle-based contrast agents and their potential applications were discussed and summarized. In addition, the recent development in nanoparticle-based multimodal contrast agents including T1-weighted MRI/computed X-ray tomography (CT) and T1-weighted MRI/optical were also described, since nanoparticles may curtail the shortcomings of single mode contrast agents in diagnostic and clinical settings by synergistically incorporating functionality.
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Affiliation(s)
- Derong Zhu
- Department of Medicinal Chemistry and Pharmaceutical Analysis, Guangdong Medical College, Dongwan 523770, Guangdong, China; E-Mail:
| | - Fuyao Liu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China; E-Mails: (F.L.); (D.L.)
| | - Lina Ma
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China; E-Mails: (F.L.); (D.L.)
| | - Dianjun Liu
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China; E-Mails: (F.L.); (D.L.)
| | - Zhenxin Wang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, Jilin, China; E-Mails: (F.L.); (D.L.)
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Han H, Song AW, Truong TK. Integrated parallel reception, excitation, and shimming (iPRES). Magn Reson Med 2013; 70:241-7. [PMID: 23629974 DOI: 10.1002/mrm.24766] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Revised: 03/15/2013] [Accepted: 03/21/2013] [Indexed: 01/06/2023]
Abstract
PURPOSE To develop a new concept for a hardware platform that enables integrated parallel reception, excitation, and shimming. THEORY This concept uses a single coil array rather than separate arrays for parallel excitation/reception and B0 shimming. It relies on a novel design that allows a radiofrequency current (for excitation/reception) and a direct current (for B0 shimming) to coexist independently in the same coil. METHODS Proof-of-concept B0 shimming experiments were performed with a two-coil array in a phantom, whereas B0 shimming simulations were performed with a 48-coil array in the human brain. RESULTS Our experiments show that individually optimized direct currents applied in each coil can reduce the B0 root-mean-square error by 62-81% and minimize distortions in echo-planar images. The simulations show that dynamic shimming with the 48-coil integrated parallel reception, excitation, and shimming array can reduce the B0 root-mean-square error in the prefrontal and temporal regions by 66-79% as compared with static second-order spherical harmonic shimming and by 12-23% as compared with dynamic shimming with a 48-coil conventional shim array. CONCLUSION Our results demonstrate the feasibility of the integrated parallel reception, excitation, and shimming concept to perform parallel excitation/reception and B0 shimming with a unified coil system as well as its promise for in vivo applications.
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Affiliation(s)
- Hui Han
- Brain Imaging and Analysis Center, Duke University, Durham, North Carolina 27705, USA
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Binks DA, Hodgson RJ, Ries ME, Foster RJ, Smye SW, McGonagle D, Radjenovic A. Quantitative parametric MRI of articular cartilage: a review of progress and open challenges. Br J Radiol 2013; 86:20120163. [PMID: 23407427 DOI: 10.1259/bjr.20120163] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
With increasing life expectancies and the desire to maintain active lifestyles well into old age, the impact of the debilitating disease osteoarthritis (OA) and its burden on healthcare services is mounting. Emerging regenerative therapies could deliver significant advances in the effective treatment of OA but rely upon the ability to identify the initial signs of tissue damage and will also benefit from quantitative assessment of tissue repair in vivo. Continued development in the field of quantitative MRI in recent years has seen the emergence of techniques able to probe the earliest biochemical changes linked with the onset of OA. Quantitative MRI measurements including T(1), T(2) and T(1ρ) relaxometry, diffusion weighted imaging and magnetisation transfer have been studied and linked to the macromolecular structure of cartilage. Delayed gadolinium-enhanced MRI of cartilage, sodium MRI and glycosaminoglycan chemical exchange saturation transfer techniques are sensitive to depletion of cartilage glycosaminoglycans and may allow detection of the earliest stages of OA. We review these current and emerging techniques for the diagnosis of early OA, evaluate the progress that has been made towards their implementation in the clinic and identify future challenges in the field.
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Affiliation(s)
- D A Binks
- Section of Musculoskeletal Disease, Leeds Institute of Molecular Medicine, University of Leeds, Leeds, UK
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48
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Affiliation(s)
- Kyryl Zagorovsky
- Institute of Biomaterials and Biomedical Engineering, Terrence Donnelly Centre for Cellular and Biomolecular Research, Department of Chemical Engineering, Materials Science and Engineering, and Chemistry, Toronto, Ontario, Canada
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Arthurs OJ, Edwards A, Austin T, Graves MJ, Lomas DJ. The challenges of neonatal magnetic resonance imaging. Pediatr Radiol 2012; 42:1183-94. [PMID: 22886375 DOI: 10.1007/s00247-012-2430-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 04/27/2012] [Accepted: 05/06/2012] [Indexed: 12/29/2022]
Abstract
Improved neonatal survival rates and antenatal diagnostic imaging is generating a growing demand for postnatal MRI examinations. Neonatal brain MRI is now becoming standard clinical care in many settings, but with the exception of some research centres, the technique has not been optimised for imaging neonates and small children. Here, we review some of the challenges involved in neonatal MRI, including recent advances in overall MR practicality and nursing practice, to address some of the ways in which the MR experience could be made more neonate-friendly.
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Affiliation(s)
- Owen J Arthurs
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, CB2 0QQ, UK.
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50
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Dorenkamp M, Roser M, Hamm B, Haverkamp W. [Magnetic resonance imaging and implantable cardiac devices. Current status and future perspectives of MR-compatible systems]. Herz 2012; 37:136-45. [PMID: 22398815 DOI: 10.1007/s00059-012-3588-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Conventional pacemakers and implantable cardioverter-defibrillators (ICD) have always been regarded as a contraindication to magnetic resonance imaging (MRI). MR-compatible systems represent a recent and particularly important innovation, since they will provide device patients with significantly improved access to MR examinations. However, the safe application of MR-compatible technology requires a detailed understanding of the strictly defined cardiologic and radiologic requirements and conditions that are to be adhered to before and during an MR examination. The present article gives an overview of problematic MR interactions with implanted devices, illustrates the most important aspects of MR-compatible pacemaker and ICD systems, analyzes their current clinical status, and offers a critical perspective.
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Affiliation(s)
- M Dorenkamp
- Medizinische Klinik mit Schwerpunkt Kardiologie, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, Berlin, Germany
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