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Sample records for additional imaging modality

  1. Multivariate Chemical Image Fusion of Vibrational Spectroscopic Imaging Modalities.

    PubMed

    Gowen, Aoife A; Dorrepaal, Ronan M

    2016-07-02

    Chemical image fusion refers to the combination of chemical images from different modalities for improved characterisation of a sample. Challenges associated with existing approaches include: difficulties with imaging the same sample area or having identical pixels across microscopic modalities, lack of prior knowledge of sample composition and lack of knowledge regarding correlation between modalities for a given sample. In addition, the multivariate structure of chemical images is often overlooked when fusion is carried out. We address these challenges by proposing a framework for multivariate chemical image fusion of vibrational spectroscopic imaging modalities, demonstrating the approach for image registration, fusion and resolution enhancement of chemical images obtained with IR and Raman microscopy.

  2. Imaging modalities in spinal disorders

    SciTech Connect

    Kricun, M.E.

    1986-01-01

    This book provides an approach to the various imaging modalities used to view the spine. It discusses the indications, limitations and practical use of each in the diagnosis, work-up and staging of various spinal disorders, and compares each of them in various clinical settings. Topics covered include low back pain syndrome, disk disease, spinal cord lesions, congenital abnormalities, and trauma.

  3. Dual-modal whole eye photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Wu, Ning; Ren, Qiushi; Li, Changhui

    2014-09-01

    We developed a prototype dual-modal ocular imaging system integrating optical-resolution photoacoustic microscopy and high-frequency ultrasound imaging modalities. This system can perform high-resolution ocular imaging from the anterior region down to the fundus area. The novel system successfully imaged the murine eyes in vivo, including iris, lens, retina, and retinal pigment epithelium. Our results demonstrated that this system has a great potential in the diagnosis of ophthalmic diseases.

  4. Improvement of modal scaling factors using mass additive technique

    NASA Technical Reports Server (NTRS)

    Zhang, Qiang; Allemang, Randall J.; Wei, Max L.; Brown, David L.

    1987-01-01

    A general investigation into the improvement of modal scaling factors of an experimental modal model using additive technique is discussed. Data base required by the proposed method consists of an experimental modal model (a set of complex eigenvalues and eigenvectors) of the original structure and a corresponding set of complex eigenvalues of the mass-added structure. Three analytical methods,i.e., first order and second order perturbation methods, and local eigenvalue modification technique, are proposed to predict the improved modal scaling factors. Difficulties encountered in scaling closely spaced modes are discussed. Methods to compute the necessary rotational modal vectors at the mass additive points are also proposed to increase the accuracy of the analytical prediction.

  5. Multi-modality imaging of small animals

    NASA Astrophysics Data System (ADS)

    Kastis, Georgios Anthony

    Over the last few years there has been a great demand for noninvasive, dedicated, small-animal imaging systems for biomedical research applications. In this dissertation we will discuss the development and performance of two gamma-ray systems and a dual modality CT/SPECT system. Initially we introduce FASTSPECT, a stationary, scintillator-based, single-photon emission computed tomography (SPECT) system that was originally built as a brain imager. We discuss its transformation into a small-animal imaging system and validate its performance by presenting high-resolution images of phantoms and animals. Furthermore, we discuss the development of an in vivo imaging protocol for rat myocardial models using FASTSPECT. The infarct size obtained from the images is quantified and compared with the myocardial infarct size measured from histology. Semiconductor detectors can exhibit good spatial and energy resolution, and therefore offer a promising alternative to scintillation technology. We discuss the performance of a semiconductor detector system, previously developed in our group, for planar and tomographic imaging of small animals. The same gamma-ray detector is used in a dual modality system for imaging mice. The system combines an anatomical imaging modality, x-ray CT, with a functional modality, SPECT. We present the development of the CT/SPECT system and illustrate its performance by presenting high-resolution images of phantoms and mice. Finally, we introduce a procedure for evaluating estimation methods without the use of a gold standard.

  6. Dual-modality imaging of function and physiology

    NASA Astrophysics Data System (ADS)

    Hasegawa, Bruce H.; Iwata, Koji; Wong, Kenneth H.; Wu, Max C.; Da Silva, Angela; Tang, Hamilton R.; Barber, William C.; Hwang, Andrew B.; Sakdinawat, Anne E.

    2002-04-01

    Dual-modality imaging is a technique where computed tomography or magnetic resonance imaging is combined with positron emission tomography or single-photon computed tomography to acquire structural and functional images with an integrated system. The data are acquired during a single procedure with the patient on a table viewed by both detectors to facilitate correlation between the structural and function images. The resulting data can be useful for localization for more specific diagnosis of disease. In addition, the anatomical information can be used to compensate the correlated radionuclide data for physical perturbations such as photon attenuation, scatter radiation, and partial volume errors. Thus, dual-modality imaging provides a priori information that can be used to improve both the visual quality and the quantitative accuracy of the radionuclide images. Dual-modality imaging systems also are being developed for biological research that involves small animals. The small-animal dual-modality systems offer advantages for measurements that currently are performed invasively using autoradiography and tissue sampling. By acquiring the required data noninvasively, dual-modality imaging has the potential to allow serial studies in a single animal, to perform measurements with fewer animals, and to improve the statistical quality of the data.

  7. Tri-modality small animal imaging system

    SciTech Connect

    Kundu, B.K.; Stolin, A.V.; Pole, J.; Baumgart, L.; Fontaine, M.; Wojcik, R.; Kross, B.; Zorn, C.; Majewski, S.; Williams, M.B.

    2006-02-01

    Our group is developing a scanner that combines x-ray, single gamma, and optical imaging on the same rotating gantry. Two functional modalities (SPECT and optical) are included because they have different strengths and weaknesses in terms of spatial and temporal decay lengths in the context of in vivo imaging, and because of the recent advent of multiple reporter gene constructs. The effect of attenuation by biological tissue on the detected intensity of the emitted signal was measured for both gamma and optical imaging. Attenuation by biological tissue was quantified for both the bioluminescent emission of luciferace and for the emission light of the near infrared fluorophore cyanine 5.5, using a fixed excitation light intensity. Experiments were performed to test the feasibility of using either single gamma or x-ray imaging to make depth-dependent corrections to the measured optical signal. Our results suggest that significant improvements in quantitation of optical emission are possible using straightforward correction techniques based on information from other modalities. Development of an integrated scanner in which data from each modality are obtained with the animal in a common configuration will greatly simplify this process.

  8. Monte Carlo simulations of medical imaging modalities

    SciTech Connect

    Estes, G.P.

    1998-09-01

    Because continuous-energy Monte Carlo radiation transport calculations can be nearly exact simulations of physical reality (within data limitations, geometric approximations, transport algorithms, etc.), it follows that one should be able to closely approximate the results of many experiments from first-principles computations. This line of reasoning has led to various MCNP studies that involve simulations of medical imaging modalities and other visualization methods such as radiography, Anger camera, computerized tomography (CT) scans, and SABRINA particle track visualization. It is the intent of this paper to summarize some of these imaging simulations in the hope of stimulating further work, especially as computer power increases. Improved interpretation and prediction of medical images should ultimately lead to enhanced medical treatments. It is also reasonable to assume that such computations could be used to design new or more effective imaging instruments.

  9. Diagnosing cardiac disease during pregnancy: imaging modalities.

    PubMed

    Ntusi, Ntobeko A; Samuels, Petronella; Moosa, Sulaiman; Mocumbi, Ana O

    2016-01-01

    Pregnant women with known or suspected cardiovascular disease (CVD) often require cardiovascular imaging during pregnancy. The accepted maximum limit of ionising radiation exposure to the foetus during pregnancy is a cumulative dose of 5 rad. Concerns related to imaging modalities that involve ionising radiation include teratogenesis, mutagenesis and childhood malignancy. Importantly, no single imaging study approaches this cautionary dose of 5 rad (50 mSv or 50 mGy). Diagnostic imaging procedures that may be used in pregnancy include chest radiography, fluoroscopy, echocardiography, invasive angiography, cardiovascular computed tomography, computed tomographic pulmonary angiography, cardiovascular magnetic resonance (CMR) and nuclear techniques. Echocardiography and CMR appear to be completely safe in pregnancy and are not associated with any adverse foetal effects, provided there are no general contra-indications to MR imaging. Concerns related to safety of imaging tests must be balanced against the importance of accurate diagnosis and thorough assessment of the pathological condition. Decisions about imaging in pregnancy are premised on understanding the physiology of pregnancy, understanding basic concepts of ionising radiation, the clinical manifestations of existent CVD in pregnancy and features of new CVD. The cardiologist/physician must understand the indications for and limitations of, and the potential harmful effects of each test during pregnancy. Current evidence suggests that a single cardiovascular radiological study during pregnancy is safe and should be undertaken at all times when clinically justified. In this article, the different imaging modalities are reviewed in terms of how they work, how safe they are and what their clinical utility in pregnancy is. Furthermore, the safety of contrast agents in pregnancy is also reviewed.

  10. Development of a triple modality small animal planar imaging system

    SciTech Connect

    A. G. Weisenberger, Z. Lee, S. Majewski, B. Kross, V. Popov, B. Welch, R. Wojcik, C. Zorn

    2006-02-01

    Recently small animal research utilizing nuclear medicine based imaging has been combined with structural anatomical imaging from x-ray radiography providing a powerful tool for animal researchers. The addition of a third modality is the goal of our instrumentation development. Thomas Jefferson National Accelerator Facility and Case Western Reserve University have been collaborating on the development of a planar imaging system which in addition to radiopharmaceutical based functional imaging and x-ray radiography structural imaging also allows for the in vivo bioluminescence imaging thus providing another functional imaging modality. For the gamma camera we use is a Hamamatsu position sensitive photomultiplier tube coupled to a pixellated NaI(TI) scintillator array with individual crystal elements 1 mm × 1 mm × 5 mm in size and a 0.25 mm septum between each element. The gamma camera has a 10 cm diameter active area and can be used for 125I, 99mT and 111In radionuclide imaging. To acquire anatomical information we are using a Rad-Icon Shad-o-Box X-ray detector that provides a field of view of 5 cm × 10 cm. The x-ray source is a Source-Ray compact x-ray generator. We are using a Princeton Instruments cooled CCD based detector for the imaging of the bio-distribution of bioluminescence. All three imaging instruments will be integrated into a single light tight / x-ray tight enclosure.

  11. Modality-Invariant Image Classification Based on Modality Uniqueness and Dictionary Learning.

    PubMed

    Kim, Seungryong; Cai, Rui; Park, Kihong; Kim, Sunok; Sohn, Kwanghoon

    2016-12-02

    We present a unified framework for image classification of image sets taken under varying modality conditions. Our method is motivated by a key observation that the image feature distribution is simultaneously influenced by the semantic-class and the modality category label, which limits the performance of conventional methods for that task. With this insight, we introduce modality uniqueness as a discriminative weight that divides each modality cluster from all other clusters. By leveraging the modality uniqueness, our framework is formulated as unsupervised modality clustering and classifier learning based on modality-invariant similarity kernel. Specifically, in the assignment step, each training image is first assigned to the most similar cluster according to its modality. In the update step, based on the current cluster hypothesis, the modality uniqueness and the sparse dictionary are updated. These two steps are formulated in an iterative manner. Based on the final clusters, a modalityinvariant marginalized kernel is then computed, where the similarities between the reconstructed features of each modality are aggregated across all clusters. Our framework enables the reliable inference of semantic-class category for an image, even across large photometric variations. Experimental results show that our method outperforms conventional methods on various benchmarks, such as landmark identification under severely varying weather conditions, domain-adapting image classification, and RGB and near-infrared (NIR) image classification.

  12. Imaging with hypertelescopes: a simple modal approach

    NASA Astrophysics Data System (ADS)

    Aime, C.

    2008-05-01

    Aims: We give a simple analysis of imaging with hypertelescopes, a technique proposed by Labeyrie to produce snapshot images using arrays of telescopes. The approach is modal: we describe the transformations induced by the densification onto a sinusoidal decomposition of the focal image instead of the usual point spread function approach. Methods: We first express the image formed at the focus of a diluted array of apertures as the product R_0(α) X_F(α) of the diffraction pattern of the elementary apertures R_0(α) by the object-dependent interference term X_F(α) between all apertures. The interference term, which can be written in the form of a Fourier Series for an extremely diluted array, produces replications of the object, which makes observing the image difficult. We express the focal image after the densification using the approach of Tallon and Tallon-Bosc. Results: The result is very simple for an extremely diluted array. We show that the focal image in a periscopic densification of the array can be written as R_0(α) X_F(α/γ), where γ is the factor of densification. There is a dilatation of the interference term while the diffraction term is unchanged. After de-zooming, the image can be written as γ2 X_F(α)R_0(γ α), an expression which clearly indicates that the final image corresponds to the center of the Fizeau image intensified by γ2. The imaging limitations of hypertelescopes are therefore those of the original configuration. The effect of the suppression of image replications is illustrated in a numerical simulation for a fully redundant configuration and a non-redundant one.

  13. Characterization of coronary atherosclerosis by intravascular imaging modalities

    PubMed Central

    Honda, Satoshi; Kanaya, Tomoaki; Noguchi, Teruo; Ogawa, Hisao; Yasuda, Satoshi

    2016-01-01

    Coronary artery disease (CAD) is highly prevalent in Western countries and is associated with morbidity, mortality, and a significant economic burden. Despite the development of anti-atherosclerotic medical therapies, many patients still continue to suffer from coronary events. This residual risk indicates the need for better risk stratification and additional therapies to achieve more reductions in cardiovascular risk. Recent advances in imaging modalities have contributed to visualizing atherosclerotic plaques and defining lesion characteristics in vivo. This innovation has been applied to refining revascularization procedure, assessment of anti-atherosclerotic drug efficacy and the detection of high-risk plaques. As such, intravascular imaging plays an important role in further improvement of cardiovascular outcomes in patients with CAD. The current article reviews available intravascular imaging modalities with regard to its method, advantage and disadvantage. PMID:27500094

  14. Multi-modality molecular imaging for gastric cancer research

    NASA Astrophysics Data System (ADS)

    Liang, Jimin; Chen, Xueli; Liu, Junting; Hu, Hao; Qu, Xiaochao; Wang, Fu; Nie, Yongzhan

    2011-12-01

    Because of the ability of integrating the strengths of different modalities and providing fully integrated information, multi-modality molecular imaging techniques provide an excellent solution to detecting and diagnosing earlier cancer, which remains difficult to achieve by using the existing techniques. In this paper, we present an overview of our research efforts on the development of the optical imaging-centric multi-modality molecular imaging platform, including the development of the imaging system, reconstruction algorithms and preclinical biomedical applications. Primary biomedical results show that the developed optical imaging-centric multi-modality molecular imaging platform may provide great potential in the preclinical biomedical applications and future clinical translation.

  15. Imaging Breast Density: Established and Emerging Modalities1

    PubMed Central

    Chen, Jeon-Hor; Gulsen, Gultekin; Su, Min-Ying

    2015-01-01

    Mammographic density has been proven as an independent risk factor for breast cancer. Women with dense breast tissue visible on a mammogram have a much higher cancer risk than women with little density. A great research effort has been devoted to incorporate breast density into risk prediction models to better estimate each individual’s cancer risk. In recent years, the passage of breast density notification legislation in many states in USA requires that every mammography report should provide information regarding the patient’s breast density. Accurate definition and measurement of breast density are thus important, which may allow all the potential clinical applications of breast density to be implemented. Because the two-dimensional mammography-based measurement is subject to tissue overlapping and thus not able to provide volumetric information, there is an urgent need to develop reliable quantitative measurements of breast density. Various new imaging technologies are being developed. Among these new modalities, volumetric mammographic density methods and three-dimensional magnetic resonance imaging are the most well studied. Besides, emerging modalities, including different x-ray–based, optical imaging, and ultrasound-based methods, have also been investigated. All these modalities may either overcome some fundamental problems related to mammographic density or provide additional density and/or compositional information. The present review article aimed to summarize the current established and emerging imaging techniques for the measurement of breast density and the evidence of the clinical use of these density methods from the literature. PMID:26692524

  16. The left bundle branch block revised with novel imaging modalities

    PubMed Central

    van Dijk, J.; Mannaerts, H.F.J.; Germans, T.; Hauer, H.A.; Knaapen, P.; Visser, C.A.; Kamp, O.

    2006-01-01

    Left bundle branch block (LBBB) is related to abnormal cardiac conduction and mechanical asynchrony and is associated with hypertension and coronary artery disease. Improved evaluation of left ventricular (LV) mechanical asynchrony is needed, because of the increasing number of patients with LBBB and heart failure. In this paper, we describe tissue Doppler imaging (TDI), strain (rate) imaging and tissue tracking in LBBB patients. A variety of patterns of mechanical activation can be observed in LBBB patients. A recent development, referred to as tissue synchronisation imaging, colour codes TDI time-to-peak systolic velocities of segments and displays mechanical asynchrony. Furthermore, real-time 3D echocardiography provides new regional information about mechanical asynchrony. Contained in an LV model and projected on a bull's eye plot, this modality helps to display the spatial distribution of mechanical asynchrony. Finally, segmental time-to-peak circumferential strain curves, produced by cardiac magnetic resonance imaging, provide additional quantification of LV mechanical asynchrony. Effects of LBBB on regional and global cardiac function are impressive, myocardial involvement seems to play a role and with the help of these novel imaging modalities, new insights continue to develop. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7 PMID:25696572

  17. Multi-modal automatic montaging of adaptive optics retinal images

    PubMed Central

    Chen, Min; Cooper, Robert F.; Han, Grace K.; Gee, James; Brainard, David H.; Morgan, Jessica I. W.

    2016-01-01

    We present a fully automated adaptive optics (AO) retinal image montaging algorithm using classic scale invariant feature transform with random sample consensus for outlier removal. Our approach is capable of using information from multiple AO modalities (confocal, split detection, and dark field) and can accurately detect discontinuities in the montage. The algorithm output is compared to manual montaging by evaluating the similarity of the overlapping regions after montaging, and calculating the detection rate of discontinuities in the montage. Our results show that the proposed algorithm has high alignment accuracy and a discontinuity detection rate that is comparable (and often superior) to manual montaging. In addition, we analyze and show the benefits of using multiple modalities in the montaging process. We provide the algorithm presented in this paper as open-source and freely available to download. PMID:28018714

  18. Multi-modal automatic montaging of adaptive optics retinal images.

    PubMed

    Chen, Min; Cooper, Robert F; Han, Grace K; Gee, James; Brainard, David H; Morgan, Jessica I W

    2016-12-01

    We present a fully automated adaptive optics (AO) retinal image montaging algorithm using classic scale invariant feature transform with random sample consensus for outlier removal. Our approach is capable of using information from multiple AO modalities (confocal, split detection, and dark field) and can accurately detect discontinuities in the montage. The algorithm output is compared to manual montaging by evaluating the similarity of the overlapping regions after montaging, and calculating the detection rate of discontinuities in the montage. Our results show that the proposed algorithm has high alignment accuracy and a discontinuity detection rate that is comparable (and often superior) to manual montaging. In addition, we analyze and show the benefits of using multiple modalities in the montaging process. We provide the algorithm presented in this paper as open-source and freely available to download.

  19. Nanogels as imaging agents for modalities spanning the electromagnetic spectrum

    PubMed Central

    Chan, Minnie

    2016-01-01

    In the past few decades, advances in imaging equipment and protocols have expanded the role of imaging in in vivo diagnosis and disease management, especially in cancer. Traditional imaging agents have rapid clearance and low specificity for disease detection. To improve accuracy in disease identification, localization and assessment, novel nanomaterials are frequently explored as imaging agents to achieve high detection specificity and sensitivity. A promising material for this purpose are hydrogel nanoparticles, whose high hydrophilicity, biocompatibility, and tunable size in the nanometer range make them ideal for imaging. These nanogels (10 to 200 nm) can circumvent uptake by the reticuloendothelial system, allowing longer circulation times than small molecules. In addition, their size/surface properties can be further tailored to optimize their pharmacokinetics for imaging of a particular disease. Herein, we provide a comprehensive review of nanogels as imaging agents in various modalities with sources of signal spanning the electromagnetic spectrum, including MRI, NIR, UV-vis, and PET. Many materials and formulation methods will be reviewed to highlight the versatility of nanogels as imaging agents. PMID:27398218

  20. Nanogels as imaging agents for modalities spanning the electromagnetic spectrum.

    PubMed

    Chan, Minnie; Almutairi, Adah

    2016-01-21

    In the past few decades, advances in imaging equipment and protocols have expanded the role of imaging in in vivo diagnosis and disease management, especially in cancer. Traditional imaging agents have rapid clearance and low specificity for disease detection. To improve accuracy in disease identification, localization and assessment, novel nanomaterials are frequently explored as imaging agents to achieve high detection specificity and sensitivity. A promising material for this purpose are hydrogel nanoparticles, whose high hydrophilicity, biocompatibility, and tunable size in the nanometer range make them ideal for imaging. These nanogels (10 to 200 nm) can circumvent uptake by the reticuloendothelial system, allowing longer circulation times than small molecules. In addition, their size/surface properties can be further tailored to optimize their pharmacokinetics for imaging of a particular disease. Herein, we provide a comprehensive review of nanogels as imaging agents in various modalities with sources of signal spanning the electromagnetic spectrum, including MRI, NIR, UV-vis, and PET. Many materials and formulation methods will be reviewed to highlight the versatility of nanogels as imaging agents.

  1. Photoacoustic and ultrasound dual-modality imaging for inflammatory arthritis

    NASA Astrophysics Data System (ADS)

    Xu, Guan; Chamberland, David; Girish, Gandikota; Wang, Xueding

    2014-03-01

    Arthritis is a leading cause of disability, affecting 46 million of the population in the U.S. Rendering new optical contrast in articular tissues at high spatial and temporal resolution, emerging photoacoustic imaging (PAI) combined with more established ultrasound (US) imaging technologies provides unique opportunities for diagnosis and treatment monitoring of inflammatory arthritis. In addition to capturing peripheral bone and soft tissue images, PAI has the capability to quantify hemodynamic properties including regional blood oxygenation and blood volume, both abnormal in synovial tissues affected by arthritis. Therefore, PAI, especially when performed together with US, should be of considerable help for further understanding the pathophysiology of arthritis as well as assisting in therapeutic decisions, including assessing the efficacy of new pharmacological therapies. In this paper, we will review our recent work on the development of PAI for application to the diagnostic imaging and therapeutic monitoring of inflammatory arthritis. We will present the imaging results from a home-built imaging system and another one based on a commercial US. The performance of PAI in evaluating pharmacological therapy on animal model of arthritis will be shown. Moreover, our resent work on PAI and US dual-modality imaging of human peripheral joints in vivo will also be presented.

  2. Diagnosis of bone metastasis: recent comparative studies of imaging modalities.

    PubMed

    Talbot, J N; Paycha, F; Balogova, S

    2011-08-01

    Various imaging modalities are currently available to diagnose bone metastasis. The two main anatomical modalities are computed tomography (CT) and magnetic resonance imaging (MRI), with many variants proposed for the MRI procedure, including diffusion-weighted imaging. The two main functional modalities are scintigraphy and PET, also with many variants in the radiopharmaceutical, from the "all purpose" 99mTc labelled bisphosphonates to very selective radiopharmaceuticals for rare neoplasia. The diagnostic strategy will become more and more individually tailored according to the patient's clinical and biological data (primary cancer type, phase of the evolution, markers of aggressiveness, serum levels of biological tracers of bone metabolism, circulating or disseminating tumour cells …). If imaging is indicated, the diagnostic strategy will also depend on the availability and the diagnostic performance of the imaging modalities. Assessment of diagnostic performance requires comparative studies, performed with an adequate methodology. The main methodological weaknesses encountered in studies intending to compare imaging modalities for diagnosing bone metastasis are summarised. Comparative studies have been reviewed, which address the initial diagnosis of skeletal metastases in solid tumours except primary bone cancers. The results of more than 140 such comparative studies are then summarised and briefly commented, according to the type of the primary cancer, and according to the compared imaging modalities.

  3. Current and Future Lymphatic Imaging Modalities for Tumor Staging

    PubMed Central

    Gao, Kuo; Liu, Tiegang; Tariq, Imran; Sajjad, Ashif; Niu, Meiying; Liu, Guokai; Mehmood, Zahid; Tian, Guihua

    2014-01-01

    Tumor progression is supported by the lymphatic system which should be scanned efficiently for tumor staging as well as the enhanced therapeutic outcomes. Poor resolution and low sensitivity is a limitation of traditional lymphatic imaging modalities; thus new noninvasive approaches like nanocarriers, magnetic resonance imaging, positron-emission tomography, and quantum dots are advantageous. Some newer modalities, which are under development, and their potential uses will also be discussed in this review. PMID:24757671

  4. Fully integrated optical coherence tomography, ultrasound, and indocyanine green-based fluorescence tri-modality system for intravascular imaging

    PubMed Central

    Li, Yan; Jing, Joseph; Qu, Yueqiao; Miao, Yusi; Zhang, Buyun; Ma, Teng; Yu, Mingyue; Zhou, Qifa; Chen, Zhongping

    2017-01-01

    We present a tri-modality imaging system and fully integrated tri-modality probe for intravascular imaging. The tri-modality imaging system is able to simultaneously acquire optical coherence tomography (OCT), ultrasound (US), and fluorescence imaging. Moreover, for fluorescence imaging, we used the FDA-approved indocyanine green (ICG) dye as the contrast agent to target lipid-loaded macrophages. We conducted imaging from a male New Zealand white rabbit to evaluate the performance of the tri-modality system. In addition, tri-modality images of rabbit aortas were correlated with hematoxylin and eosin (H&E) histology to check the measurement accuracy. The fully integrated miniature tri-modality probe, together with the use of ICG dye suggest that the system is of great potential for providing a more accurate assessment of vulnerable plaques in clinical applications. PMID:28271001

  5. Motion based X-ray imaging modality.

    PubMed

    Szigeti, Krisztián; Máthé, Domokos; Osváth, Szabolcs

    2014-10-01

    A new X-ray imaging method (patent pending) was developed to visualize function-related motion information. We modify existing X-ray imaging methods to provide four images without increasing the necessary measurement time or radiation dose. The most important of these images is a new "kinetic" image that represents motions inside the object or living body. The motion-based contrast of the kinetic image can help visualize details that were not accessible before. The broad range of the movements and high sensitivity of the method are illustrated by imaging the mechanics of a working clock and the chest of a living African clawed frog (Xenopus laevis). The heart, valves, aorta, and lungs of the frog are clearly visualized in spite of the low soft tissue contrast of the animal. The new technology also reconstructs a "static" image similar to the existing conventional X-ray image. The static image shows practically the same information as the conventional image. The new technology presents two more images which show the point-wise errors of the static and kinetic images. This technique gives a better estimation of errors than present methods because it is based entirely on measured data. The new technology could be used in imaging cardiopulmonary movements, nondestructive testing, or port security screening.

  6. Instrumentation challenges in multi-modality imaging

    NASA Astrophysics Data System (ADS)

    Brasse, D.; Boisson, F.

    2016-02-01

    Based on different physical principles, imaging procedures currently used in both clinical and preclinical applications present different performance that allow researchers to achieve a large number of studies. However, the relevance of obtaining a maximum of information relating to the same subject is undeniable. The last two decades have thus seen the advent of a full-fledged research axis, the multimodal in vivo imaging. Whether from an instrumentation point of view, for medical research or the development of new probes, all these research works illustrate the growing interest of the scientific community for multimodal imaging, which can be approached with different backgrounds and perspectives from engineers to end-users point of views. In the present review, we discuss the multimodal imaging concept, which focuses not only on PET/CT and PET/MRI instrumentation but also on recent investigations of what could become a possible future in the field.

  7. Three-dimensional imaging modalities in endodontics

    PubMed Central

    Mao, Teresa

    2014-01-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome. PMID:25279337

  8. Three-dimensional imaging modalities in endodontics.

    PubMed

    Mao, Teresa; Neelakantan, Prasanna

    2014-09-01

    Recent research in endodontics has highlighted the need for three-dimensional imaging in the clinical arena as well as in research. Three-dimensional imaging using computed tomography (CT) has been used in endodontics over the past decade. Three types of CT scans have been studied in endodontics, namely cone-beam CT, spiral CT, and peripheral quantitative CT. Contemporary endodontics places an emphasis on the use of cone-beam CT for an accurate diagnosis of parameters that cannot be visualized on a two-dimensional image. This review discusses the role of CT in endodontics, pertaining to its importance in the diagnosis of root canal anatomy, detection of peri-radicular lesions, diagnosis of trauma and resorption, presurgical assessment, and evaluation of the treatment outcome.

  9. Implementation and applications of dual-modality imaging

    NASA Astrophysics Data System (ADS)

    Hasegawa, Bruce H.; Barber, William C.; Funk, Tobias; Hwang, Andrew B.; Taylor, Carmen; Sun, Mingshan; Seo, Youngho

    2004-06-01

    In medical diagnosis, functional or physiological data can be acquired using radionuclide imaging with positron emission tomography or with single-photon emission computed tomography. However, anatomical or structural data can be acquired using X-ray computed tomography. In dual-modality imaging, both radionuclide and X-ray detectors are incorporated in an imaging system to allow both functional and structural data to be acquired in a single procedure without removing the patient from the imaging system. In a clinical setting, dual-modality imaging systems commonly are used to localize radiopharmaceutical uptake with respect to the patient's anatomy. This helps the clinician to differentiate disease from regions of normal radiopharmaceutical accumulation, to improve diagnosis or cancer staging, or to facilitate planning for radiation therapy or surgery. While initial applications of dual-modality imaging were developed for clinical imaging on humans, it now is recognized that these systems have potentially important applications for imaging small animals involved in experimental studies including basic investigations of mammalian biology and development of new pharmaceuticals for diagnosis or treatment of disease.

  10. Radiation dose reduction and new image modalities development for interventional C-arm imaging system

    NASA Astrophysics Data System (ADS)

    Niu, Kai

    Cardiovascular disease and stroke are the leading health problems and causes of death in the US. Due to the minimally invasive nature of the evolution of image guided techniques, interventional radiological procedures are becoming more common and are preferred in treating many cardiovascular diseases and strokes. In addition, with the recent advances in hardware and device technology, the speed and efficacy of interventional treatment has significantly improved. This implies that more image modalities can be developed based on the current C-arm system and patients treated in interventional suites can potentially experience better health outcomes. However, during the treatment patients are irradiated with substantial amounts of ionizing radiation with a high dose rate (digital subtraction angiography (DSA) with 3muGy/frame and 3D cone beam CT image with 0.36muGy/frame for a Siemens Artis Zee biplane system) and/or a long irradiation time (a roadmapping image sequence can be as long as one hour during aneurysm embolization). As a result, the patient entrance dose is extremely high. Despite the fact that the radiation dose is already substantial, image quality is not always satisfactory. By default a temporal average is used in roadmapping images to overcome poor image quality, but this technique can result in motion blurred images. Therefore, reducing radiation dose while maintaining or even improving the image quality is an important area for continued research. This thesis is focused on improving the clinical applications of C-arm cone beam CT systems in two ways: (1) Improve the performance of current image modalities on the C-arm system. (2) Develop new image modalities based on the current system. To be more specific, the objectives are to reduce radiation dose for current modalities (e.g., DSA, fluoroscopy, roadmapping, and cone beam CT) and enable cone beam CT perfusion and time resolved cone beam CT angiography that can be used to diagnose and triage acute

  11. [Knee imaging: what is the best modality].

    PubMed

    Tavernier, T; Dejour, D

    2001-03-01

    A wide range of exams are available for imaging the knee: standard radiography, ultrasound, bone scintigraphy, CT scan, arthroscan, MRI, arthro-MRI. The radiologist must be aware of the performance capacities of each technique in order to orient the clinician's choice towards the most appropriate exam in a given clinical situation. In the first part of this paper, we examine the performances, advantages and disadvantages of each technique: exam conditions (patient position, incidence, slice thickness, sequence.) are detailed as required. The second part is a practical guide for some typical clinical situations with decision trees for ordering necessary and sufficient explorations.

  12. Recent developments of imaging modalities of carotid artery stenting.

    PubMed

    Umemoto, Tomoyuki; Pacchioni, Andrea; Nikas, Dimitrios; Reimers, Bernhard

    2017-02-01

    Compared with conventional angiogram-guided procedure, intravascular imaging modalities give us a lot of useful information to make the procedure better. Intravascular imaging modalities give us the information about lesion characters, reference vessel diameter and the interaction between the stent strut and the plaque such as stent strut malapposition or plaque prolapse in real time during the procedure. We can change our strategy according to this information. Intravascular ultrasound (IVUS) is a most common intravascular imaging modality during carotid artery stenting (CAS) in these days. Its advantage is easy to use compared with optical coherence tomograpy (OCT) which has been reported recently in some case reports or case series. However, due to its high resolution, OCT provides more detailed information especially about plaque prolapse and strut malapposition. IVUS and OCT have a potential to improve acute result and reduce the procedural complication by providing the data of lesion character, reference vessel diameter and the interaction of stent strut and vessel wall. Interventionalists who perform CAS procedure should acquire proficiency in imaging modalities during CAS procedure.

  13. Role of imaging modalities in diagnosis and management of pyomyositis

    SciTech Connect

    Yousefzadeh, D.K.; Mulligan, G.M.; Young, C.S.; Schumann, E.M.; Bosworth, D.E.; Pringle, K.C.

    1982-08-01

    A case of tropical pyomyositis in a temperate climate is reported and 29 more cases are reviewed from the literature. Because of its rarity and deceiving clinical presentation, the disorder may go unrecognized for weeks in nontropical regions. The role of various imaging modalities in timely and accurate diagnosis and nonsurgical management of this disorder is discussed.

  14. Optical tomography: Development of a new medical imaging modality

    SciTech Connect

    Hebden, Jeremy C.

    1998-08-28

    The demonstrated success of near-infrared spectroscopy as a diagnostic tool in medicine has encouraged physicists to pursue the development of an imaging technique based on the transmittance of optical wavelengths through tissue. Potential clinical applications include a means of detecting breast disease, and a cerebral imaging modality for mapping oxygenation and haemodynamics in the brain of newborn infants. Imaging of tissues with light is severely restricted by the overwhelming scatter which occurs when optical radiation propagates through tissue. However, recent innovations in technology and the development of new tomographic reconstruction procedures suggest that a clinically viable imaging modality is achievable. In this paper the recent progress in this field of research is reviewed, and the prospects for ultimate success are discussed.

  15. Thermographic Assessment of a Vascular Malformation of the Hand: A New Imaging Modality

    PubMed Central

    Hardwicke, Joseph T.; Titley, O. Garth

    2016-01-01

    Vascular malformations of the hand are rare. Angiography is the current Gold Standard imaging modality. Thermal imaging is an emerging noninvasive, noncontact technology that does not require intravenous contrast agents. We present the case of a patient with an arteriovenous malformation affecting the hand in which thermal imaging has been used as an adjunct to capture baseline images to allow monitoring of progression. We suggest that thermal imaging provides an adjunct that can be used in addition to clinical examination and/or angiography for the diagnosis and routine follow-up of conservatively managed arteriovenous malformations, to monitor progression or vascular steal, and also for recording recurrence after surgical excision for which there is known to be a significant incidence. With the benefit of being a noninvasive imaging modality that does not require intravenous contrast, or ionizing radiation exposure, office-based thermal imaging may become commonplace. PMID:27195175

  16. Imaging of congenital heart disease in adults: choice of modalities.

    PubMed

    Orwat, Stefan; Diller, Gerhard-Paul; Baumgartner, Helmut

    2014-01-01

    Major advances in noninvasive imaging of adult congenital heart disease have been accomplished. These tools play now a key role in comprehensive diagnostic work-up, decision for intervention, evaluation for the suitability of specific therapeutic options, monitoring of interventions and regular follow-up. Besides echocardiography, magnetic resonance (CMR) and computed tomography (CT) have gained particular importance. The choice of imaging modality has thus become a critical issue. This review summarizes strengths and limitations of the different imaging modalities and how they may be used in a complementary fashion. Echocardiography obviously remains the workhorse of imaging routinely used in all patients. However, in complex disease and after surgery echocardiography alone frequently remains insufficient. CMR is particularly useful in this setting and allows reproducible and accurate quantification of ventricular function and comprehensive assessment of cardiac anatomy, aorta, pulmonary arteries and venous return including complex flow measurements. CT is preferred when CMR is contraindicated, when superior spatial resolution is required or when "metallic" artefacts limit CMR imaging. In conclusion, the use of currently available imaging modalities in adult congenital heart disease needs to be complementary. Echocardiography remains the basis tool, CMR and CT should be added considering specific open questions and the ability to answer them, availability and economic issues.

  17. Diagnosing, planning and evaluating osteochondral ankle defects with imaging modalities

    PubMed Central

    van Bergen, Christiaan JA; Gerards, Rogier M; Opdam, Kim TM; Terra, Maaike P; Kerkhoffs, Gino MMJ

    2015-01-01

    This current concepts review outlines the role of different imaging modalities in the diagnosis, preoperative planning, and follow-up of osteochondral ankle defects. An osteochondral ankle defect involves the articular cartilage and subchondral bone (usually of the talus) and is mostly caused by an ankle supination trauma. Conventional radiographs are useful as an initial imaging tool in the diagnostic process, but have only moderate sensitivity for the detection of osteochondral defects. Computed tomography (CT) and magnetic resonance imaging (MRI) are more accurate imaging modalities. Recently, ultrasonography and single photon emission CT have been described for the evaluation of osteochondral talar defects. CT is the most valuable modality for assessing the exact location and size of bony lesions. Cartilage and subchondral bone damage can be visualized using MRI, but the defect size tends to be overestimated due to bone edema. CT with the ankle in full plantar flexion has been shown a reliable tool for preoperative planning of the surgical approach. Postoperative imaging is useful for objective assessment of repair tissue or degenerative changes of the ankle joint. Plain radiography, CT and MRI have been used in outcome studies, and different scoring systems are available. PMID:26716090

  18. Image and Dose Simulation in Support of New Mammography Modalities

    SciTech Connect

    Kuruvilla Verghese

    2002-04-05

    This report summarizes the highlights of the research performed under the 2-year NEER grant from the Department of Energy. The primary outcome of the work was a new Monte Carlo code, MCMIS-DS, for Monte Carlo for Mammography Image Simulation including Differential Sampling. The code was written to generate simulated images and dose distributions from two different new digital x-ray imaging modalities, namely, synchrotron imaging (SI) and a slot geometry digital mammography system called Fisher Senoscan. A differential sampling scheme was added to the code to generate multiple images that included variations in the parameters of the measurement system and the object in a single execution of the code. The code is to serve multiple purposes; (1) to answer questions regarding the contribution of scattered photons to images, (2) for use in design optimization studies, and (3) to do up to second-order perturbation studies to assess the effects of design parameter variations and/or physical parameters of the object (the breast) without having to re-run the code for each set of varied parameters. The accuracy and fidelity of the code were validated by a large variety of benchmark studies using published data and also using experimental results from mammography phantoms on both imaging modalities.

  19. Current Imaging Modalities for assessing Ocular Blood Flow in Glaucoma

    PubMed Central

    Mohindroo, Chirayu; Kumar, Suresh

    2016-01-01

    Glaucoma may be caused by an interplay of elevated intraocular pressure (IOP), vascular, genetic, anatomical, brain, and immune factors. The direct assessment of ocular hemodynam-ics offers promise for glaucoma detection, differentiation, and possibly new treatment modalities. All the methods currently in use to measure ocular blood flow have inherent limitations and measure different aspects of ocular blood flow. This review article attempts to provide detailed information on ocular perfu-sion pressure as well as an overview of the newly developed imaging technologies used to investigate ocular blood flow in glaucoma patients. How to cite this article Mohindroo C, Ichhpujani P, Kumar S. Current Imaging Modalities for assessing Ocular Blood Flow in Glaucoma. J Curr Glaucoma Pract 2016;10(3):104-112. PMID:27857490

  20. Radiological Evaluation of Ambiguous Genitalia with Various Imaging Modalities

    NASA Astrophysics Data System (ADS)

    Ravi, N.; Bindushree, Kadakola

    2012-07-01

    Disorders of sex development (DSDs) are congenital conditions in which the development of chromosomal, gonadal, or anatomic sex is atypical. These can be classified broadly into four categories on the basis of gonadal histologic features: female pseudohermaphroditism (46,XX with two ovaries); male pseudohermaphroditism (46,XY with two testes); true hermaphroditism (ovotesticular DSD) (both ovarian and testicular tissues); and gonadal dysgenesis, either mixed (a testis and a streak gonad) or pure (bilateral streak gonads). Imaging plays an important role in demonstrating the anatomy and associated anomalies. Ultrasonography is the primary modality for demonstrating internal organs and magnetic resonance imaging is used as an adjunct modality to assess for internal gonads and genitalia. Early and appropriate gender assignment is necessary for healthy physical and psychologic development of children with ambiguous genitalia. Gender assignment can be facilitated with a team approach that involves a pediatric endocrinologist, geneticist, urologist, psychiatrist, social worker, neonatologist, nurse, and radiologist, allowing timely diagnosis and proper management. We describe case series on ambiguous genitalia presented to our department who were evaluated with multiple imaging modalities.

  1. HIGH-CONTRAST IMAGING VIA MODAL CONVERGENCE OF DEFORMABLE MIRROR

    SciTech Connect

    Wang Feiling

    2012-06-01

    For extremely high contrast imaging, such as direct observation of faint stellar companions, an adaptive optics system is required to produce low-halo and low-speckle regions in the focal plane. A method for deformable mirror control is proposed to achieve this goal. The method relies on a modal convergence of the deformable mirror driven by a focal-plane metric. The modal sets are derived from the Walsh functions. The Walsh-function modes serve two purposes: the expansion of the actuator displacements and the expansion of the phase functions. Taking advantage of the unique properties of the modal functions, a universal control algorithm is devised for the realization of high-contrast focal planes with and without the help of conventional coronagraphy. Numerical modeling is conducted to simulate complete imaging systems under various scenarios. It is shown that the proposed method reliably produces high-contrast focal planes using either a segmented or a membrane mirror. In the presence of random aberration the method is shown to be able to maintain high-contrast focal planes. Requiring neither retrieval of electric fields nor detailed knowledge of the deformable mirrors, this technique may allow high-contrast imaging in real time.

  2. Three-dimensional Intraoperative Imaging Modalities in Orthopaedic Surgery: A Narrative Review.

    PubMed

    Qureshi, Sheeraz; Lu, Young; McAnany, Steven; Baird, Evan

    2014-12-01

    Intraoperative imaging and navigation systems have revolutionized orthopaedic surgery for the spine, joints, and orthopaedic trauma. Imaging modalities such as the isocentric C-arm, O-arm imaging, and intraoperative MRI or navigation systems allow the visualization of surgical instruments and implants relative to a three-dimensional CT image or MRI. Studies show that these technologies lower the rates of implant misplacement and inadequate fracture reduction, thereby improving surgical outcomes and reducing reoperation rates. An additional benefit is reduced radiation exposure compared with that for conventional fluoroscopy. Concerns surrounding adoption of these technologies include cost and increased operating times, but improvements in design and protocol may improve the integration of these imaging modalities into the operating room.

  3. Novel Strategy for Preparing Dual-Modality Optical/PET Imaging Probes via Photo-Click Chemistry.

    PubMed

    Sun, Lingyi; Ding, Jiule; Xing, Wei; Gai, Yongkang; Sheng, Jing; Zeng, Dexing

    2016-05-18

    Preparation of small molecule based dual-modality probes remains a challenging task due to the complicated synthetic procedure. In this study, a novel concise and generic strategy for preparing dual-modality optical/PET imaging probes via photo-click chemistry was developed, in which the diazole photo-click linker functioned not only as a bridge between the targeting-ligand and the PET imaging moiety, but also as the fluorophore for optical imaging. A dual-modality AE105 peptidic probe was successfully generated via this strategy and subsequently applied in the fluorescent staining of U87MG cells and the (68)Ga based PET imaging of mice bearing U87MG xenograft. In addition, dual-modality monoclonal antibody cetuximab has also been generated via this strategy and labeled with (64)Cu for PET imaging studies, broadening the application of this strategy to include the preparation of macromolecule based imaging probes.

  4. A dual-modal retinal imaging system with adaptive optics

    PubMed Central

    Meadway, Alexander; Girkin, Christopher A.; Zhang, Yuhua

    2013-01-01

    An adaptive optics scanning laser ophthalmoscope (AO-SLO) is adapted to provide optical coherence tomography (OCT) imaging. The AO-SLO function is unchanged. The system uses the same light source, scanning optics, and adaptive optics in both imaging modes. The result is a dual-modal system that can acquire retinal images in both en face and cross-section planes at the single cell level. A new spectral shaping method is developed to reduce the large sidelobes in the coherence profile of the OCT imaging when a non-ideal source is used with a minimal introduction of noise. The technique uses a combination of two existing digital techniques. The thickness and position of the traditionally named inner segment/outer segment junction are measured from individual photoreceptors. In-vivo images of healthy and diseased human retinas are demonstrated. PMID:24514529

  5. Development of single-channel stereoscopic video imaging modality for real-time retinal imaging

    NASA Astrophysics Data System (ADS)

    Radfar, Edalat; Park, Jihoon; Lee, Sangyeob; Ha, Myungjin; Yu, Sungkon; Jang, Seulki; Jung, Byungjo

    2016-03-01

    Stereoscopic retinal image can effectively help doctors. Most of stereo imaging surgical microscopes are based on dual optical channels and benefit from dual cameras in which left and right cameras capture corresponding left and right eye views. This study developed a single-channel stereoscopic retinal imaging modality based on a transparent rotating deflector (TRD). Two different viewing angles are generated by imaging through the TRD which is mounted on a motor synchronized with a camera and is placed in single optical channel. Because of the function of objective lens in the imaging modality which generate stereo-image from an object at its focal point, and according to eye structure, the optical set up of the imaging modality can compatible for retinal imaging when the cornea and eye lens are engaged in objective lens.

  6. Inert fluorinated gas MRI: a new pulmonary imaging modality.

    PubMed

    Couch, Marcus J; Ball, Iain K; Li, Tao; Fox, Matthew S; Ouriadov, Alexei V; Biman, Birubi; Albert, Mitchell S

    2014-12-01

    Fluorine-19 ((19)F) MRI of the lungs using inhaled inert fluorinated gases can potentially provide high quality images of the lungs that are similar in quality to those from hyperpolarized (HP) noble gas MRI. Inert fluorinated gases have the advantages of being nontoxic, abundant, and inexpensive compared with HP gases. Due to the high gyromagnetic ratio of (19)F, there is sufficient thermally polarized signal for imaging, and averaging within a single breath-hold is possible due to short longitudinal relaxation times. Therefore, the gases do not need to be hyperpolarized prior to their use in MRI. This eliminates the need for an expensive polarizer and expensive isotopes. Inert fluorinated gas MRI of the lungs has been previously demonstrated in animals, and more recently in healthy volunteers and patients with lung diseases. The ongoing improvements in image quality demonstrate the potential of (19)F MRI for visualizing the distribution of ventilation in human lungs and detecting functional biomarkers. In this brief review, the development of inert fluorinated gas MRI, current progress, and future prospects are discussed. The current state of HP noble gas MRI is also briefly discussed in order to provide context to the development of this new imaging modality. Overall, this may be a viable clinical imaging modality that can provide useful information for the diagnosis and management of chronic respiratory diseases.

  7. Optical imaging modalities: From design to diagnosis of skin cancer

    NASA Astrophysics Data System (ADS)

    Korde, Vrushali Raj

    This study investigates three high resolution optical imaging modalities to better detect and diagnose skin cancer. The ideal high resolution optical imaging system can visualize pre-malignant tissue growth non-invasively with resolution comparable to histology. I examined 3 modalities which approached this goal. The first method examined was high magnification microscopy of thin stained tissue sections, together with a statistical analysis of nuclear chromatin patterns termed Karyometry. This method has subcellular resolution, but it necessitates taking a biopsy at the desired tissue site and imaging the tissue ex-vivo. My part of this study was to develop an automated nuclear segmentation algorithm to segment cell nuclei in skin histology images for karyometric analysis. The results of this algorithm were compared to hand segmented cell nuclei in the same images, and it was concluded that the automated segmentations can be used for karyometric analysis. The second optical imaging modality I investigated was Optical Coherence Tomography (OCT). OCT is analogous to ultrasound, in which sound waves are delivered into the body and the echo time and reflected signal magnitude are measured. Due to the fast speed of light and detector temporal integration times, low coherence interferometry is needed to gate the backscattered light. OCT acquires cross sectional images, and has an axial resolution of 1-15 mum (depending on the source bandwidth) and a lateral resolution of 10-20 mum (depending on the sample arm optics). While it is not capable of achieving subcellular resolution, it is a non-invasive imaging modality. OCT was used in this study to evaluate skin along a continuum from normal to sun damaged to precancer. I developed algorithms to detect statistically significant differences between images of sun protected and sun damaged skin, as well as between undiseased and precancerous skin. An Optical Coherence Microscopy (OCM) endoscope was developed in the third

  8. Dual-Modality PET/Ultrasound imaging of the Prostate

    SciTech Connect

    Huber, Jennifer S.; Moses, William W.; Pouliot, Jean; Hsu, I.C.

    2005-11-11

    Functional imaging with positron emission tomography (PET)will detect malignant tumors in the prostate and/or prostate bed, as well as possibly help determine tumor ''aggressiveness''. However, the relative uptake in a prostate tumor can be so great that few other anatomical landmarks are visible in a PET image. Ultrasound imaging with a transrectal probe provides anatomical detail in the prostate region that can be co-registered with the sensitive functional information from the PET imaging. Imaging the prostate with both PET and transrectal ultrasound (TRUS) will help determine the location of any cancer within the prostate region. This dual-modality imaging should help provide better detection and treatment of prostate cancer. LBNL has built a high performance positron emission tomograph optimized to image the prostate.Compared to a standard whole-body PET camera, our prostate-optimized PET camera has the same sensitivity and resolution, less backgrounds and lower cost. We plan to develop the hardware and software tools needed for a validated dual PET/TRUS prostate imaging system. We also plan to develop dual prostate imaging with PET and external transabdominal ultrasound, in case the TRUS system is too uncomfortable for some patients. We present the design and intended clinical uses for these dual imaging systems.

  9. Imaging modalities in mild traumatic brain injury and sports concussion.

    PubMed

    Gonzalez, Peter G; Walker, Matthew T

    2011-10-01

    Mild traumatic brain injury is a significant public health issue that has been gaining considerable attention over the past few years. After injury, a large percentage of patients experience postconcussive symptoms that affect work and school performance and that carry significant medicolegal implications. Conventional imaging modalities (computed tomography and magnetic resonance imaging) are insensitive to microstructural changes and underestimate the degree of diffuse axonal injury and metabolic changes. Newer imaging techniques have attempted to better diagnose and characterize diffuse axonal injury and the metabolic and functional aspects of traumatic brain injury. The following review article summarizes the currently available imaging studies and describes the novel and more investigational techniques available for mild traumatic brain injury. A suggested algorithm is offered.

  10. Utility of noninvasive imaging modalities in a retina practice

    PubMed Central

    Jayadev, Chaitra; Jain, Nimesh; Sachdev, Sonia; Mohan, Ashwin; Yadav, Naresh Kumar

    2016-01-01

    Fluorescein angiography (FFA) has been the gold standard to understand, diagnose and treat retinal disorders. However, being an invasive procedure it has several limitations including adverse drug reactions. Hence, noninvasive tests that can be repeated during the course of the disease are the need of the hour. The aim of our study was to compare images of patients with retinal microvasculature pathology taken from three different imaging modalities (invasive vs. noninvasive). Lesions were detected more easily and with a greater resolution of morphology on retinal function imaging (RFI) and optical coherence tomography angiography (angio-OCT). Functional integrity of the vessels was better delineated on FFA. RFI and angio-OCT are noninvasive rapid and efficient methods to image vascular conditions with easy repeatability and negligible adverse effects. PMID:28112141

  11. Enhancing image classification models with multi-modal biomarkers

    NASA Astrophysics Data System (ADS)

    Caban, Jesus J.; Liao, David; Yao, Jianhua; Mollura, Daniel J.; Gochuico, Bernadette; Yoo, Terry

    2011-03-01

    Currently, most computer-aided diagnosis (CAD) systems rely on image analysis and statistical models to diagnose, quantify, and monitor the progression of a particular disease. In general, CAD systems have proven to be effective at providing quantitative measurements and assisting physicians during the decision-making process. As the need for more flexible and effective CADs continues to grow, questions about how to enhance their accuracy have surged. In this paper, we show how statistical image models can be augmented with multi-modal physiological values to create more robust, stable, and accurate CAD systems. In particular, this paper demonstrates how highly correlated blood and EKG features can be treated as biomarkers and used to enhance image classification models designed to automatically score subjects with pulmonary fibrosis. In our results, a 3-5% improvement was observed when comparing the accuracy of CADs that use multi-modal biomarkers with those that only used image features. Our results show that lab values such as Erythrocyte Sedimentation Rate and Fibrinogen, as well as EKG measurements such as QRS and I:40, are statistically significant and can provide valuable insights about the severity of the pulmonary fibrosis disease.

  12. FULLY CONVOLUTIONAL NETWORKS FOR MULTI-MODALITY ISOINTENSE INFANT BRAIN IMAGE SEGMENTATION.

    PubMed

    Nie, Dong; Wang, Li; Gao, Yaozong; Shen, Dinggang

    The segmentation of infant brain tissue images into white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF) plays an important role in studying early brain development. In the isointense phase (approximately 6-8 months of age), WM and GM exhibit similar levels of intensity in both T1 and T2 MR images, resulting in extremely low tissue contrast and thus making the tissue segmentation very challenging. The existing methods for tissue segmentation in this isointense phase usually employ patch-based sparse labeling on single T1, T2 or fractional anisotropy (FA) modality or their simply-stacked combinations without fully exploring the multi-modality information. To address the challenge, in this paper, we propose to use fully convolutional networks (FCNs) for the segmentation of isointense phase brain MR images. Instead of simply stacking the three modalities, we train one network for each modality image, and then fuse their high-layer features together for final segmentation. Specifically, we conduct a convolution-pooling stream for multimodality information from T1, T2, and FA images separately, and then combine them in high-layer for finally generating the segmentation maps as the outputs. We compared the performance of our approach with that of the commonly used segmentation methods on a set of manually segmented isointense phase brain images. Results showed that our proposed model significantly outperformed previous methods in terms of accuracy. In addition, our results also indicated a better way of integrating multi-modality images, which leads to performance improvement.

  13. FULLY CONVOLUTIONAL NETWORKS FOR MULTI-MODALITY ISOINTENSE INFANT BRAIN IMAGE SEGMENTATION

    PubMed Central

    Nie, Dong; Wang, Li; Gao, Yaozong; Shen, Dinggang

    2016-01-01

    The segmentation of infant brain tissue images into white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF) plays an important role in studying early brain development. In the isointense phase (approximately 6–8 months of age), WM and GM exhibit similar levels of intensity in both T1 and T2 MR images, resulting in extremely low tissue contrast and thus making the tissue segmentation very challenging. The existing methods for tissue segmentation in this isointense phase usually employ patch-based sparse labeling on single T1, T2 or fractional anisotropy (FA) modality or their simply-stacked combinations without fully exploring the multi-modality information. To address the challenge, in this paper, we propose to use fully convolutional networks (FCNs) for the segmentation of isointense phase brain MR images. Instead of simply stacking the three modalities, we train one network for each modality image, and then fuse their high-layer features together for final segmentation. Specifically, we conduct a convolution-pooling stream for multimodality information from T1, T2, and FA images separately, and then combine them in high-layer for finally generating the segmentation maps as the outputs. We compared the performance of our approach with that of the commonly used segmentation methods on a set of manually segmented isointense phase brain images. Results showed that our proposed model significantly outperformed previous methods in terms of accuracy. In addition, our results also indicated a better way of integrating multi-modality images, which leads to performance improvement. PMID:27668065

  14. TU-C-BRD-01: Image Guided SBRT I: Multi-Modality 4D Imaging

    SciTech Connect

    Cai, J; Mageras, G; Pan, T

    2014-06-15

    Motion management is one of the critical technical challenges for radiation therapy. 4D imaging has been rapidly adopted as essential tool to assess organ motion associated with respiratory breathing. A variety of 4D imaging techniques have been developed and are currently under development based on different imaging modalities such as CT, MRI, PET, and CBCT. Each modality provides specific and complementary information about organ and tumor respiratory motion. Effective use of each different technique or combined use of different techniques can introduce a comprehensive management of tumor motion. Specifically, these techniques have afforded tremendous opportunities to better define and delineate tumor volumes, more accurately perform patient positioning, and effectively apply highly conformal therapy techniques such as IMRT and SBRT. Successful implementation requires good understanding of not only each technique, including unique features, limitations, artifacts, imaging acquisition and process, but also how to systematically apply the information obtained from different imaging modalities using proper tools such as deformable image registration. Furthermore, it is important to understand the differences in the effects of breathing variation between different imaging modalities. A comprehensive motion management strategy using multi-modality 4D imaging has shown promise in improving patient care, but at the same time faces significant challenges. This session will focuses on the current status and advances in imaging respiration-induced organ motion with different imaging modalities: 4D-CT, 4D-MRI, 4D-PET, and 4D-CBCT/DTS. Learning Objectives: Understand the need and role of multimodality 4D imaging in radiation therapy. Understand the underlying physics behind each 4D imaging technique. Recognize the advantages and limitations of each 4D imaging technique.

  15. Current Imaging Modalities for assessing Ocular Blood Flow in Glaucoma.

    PubMed

    Mohindroo, Chirayu; Ichhpujani, Parul; Kumar, Suresh

    2016-01-01

    Glaucoma may be caused by an interplay of elevated intraocular pressure (IOP), vascular, genetic, anatomical, brain, and immune factors. The direct assessment of ocular hemodynam-ics offers promise for glaucoma detection, differentiation, and possibly new treatment modalities. All the methods currently in use to measure ocular blood flow have inherent limitations and measure different aspects of ocular blood flow. This review article attempts to provide detailed information on ocular perfu-sion pressure as well as an overview of the newly developed imaging technologies used to investigate ocular blood flow in glaucoma patients.

  16. Neurosurgical confocal endomicroscopy: A review of contrast agents, confocal systems, and future imaging modalities

    PubMed Central

    Zehri, Aqib H.; Ramey, Wyatt; Georges, Joseph F.; Mooney, Michael A.; Martirosyan, Nikolay L.; Preul, Mark C.; Nakaji, Peter

    2014-01-01

    Background: The clinical application of fluorescent contrast agents (fluorescein, indocyanine green, and aminolevulinic acid) with intraoperative microscopy has led to advances in intraoperative brain tumor imaging. Their properties, mechanism of action, history of use, and safety are analyzed in this report along with a review of current laser scanning confocal endomicroscopy systems. Additional imaging modalities with potential neurosurgical utility are also analyzed. Methods: A comprehensive literature search was performed utilizing PubMed and key words: In vivo confocal microscopy, confocal endomicroscopy, fluorescence imaging, in vivo diagnostics/neoplasm, in vivo molecular imaging, and optical imaging. Articles were reviewed that discussed clinically available fluorophores in neurosurgery, confocal endomicroscopy instrumentation, confocal microscopy systems, and intraoperative cancer diagnostics. Results: Current clinically available fluorescent contrast agents have specific properties that provide microscopic delineation of tumors when imaged with laser scanning confocal endomicroscopes. Other imaging modalities such as coherent anti-Stokes Raman scattering (CARS) microscopy, confocal reflectance microscopy, fluorescent lifetime imaging (FLIM), two-photon microscopy, and second harmonic generation may also have potential in neurosurgical applications. Conclusion: In addition to guiding tumor resection, intraoperative fluorescence and microscopy have the potential to facilitate tumor identification and complement frozen section analysis during surgery by providing real-time histological assessment. Further research, including clinical trials, is necessary to test the efficacy of fluorescent contrast agents and optical imaging instrumentation in order to establish their role in neurosurgery. PMID:24872922

  17. Dual Modality Noncontact Photoacoustic and Spectral Domain OCT Imaging

    PubMed Central

    Leiss-Holzinger, Elisabeth; Bauer-Marschallinger, Johannes; Hochreiner, Armin; Hollinger, Philipp; Berer, Thomas

    2016-01-01

    We developed a multimodal imaging system, combining noncontact photoacoustic imaging and optical coherence tomography (OCT). Photoacoustic signals are recorded without contact to the specimens’ surface by using an interferometric technique. The interferometer is realized within a fiber-optic network using a fiber laser at 1550 nm as source. The fiber-optic network allows the integration of a fiber-based OCT system operating at a wavelength region around 1310 nm. Light from the fiber laser and the OCT source are multiplexed into one fiber using wavelength-division multiplexing. The same focusing optics is used for both modalities. Back-reflected light from the sample is demultiplexed and guided to the respective imaging systems. As the same optical components are used for OCT and photoacoustic imaging, the obtained images are co-registered intrinsically in lateral direction. Three-dimensional imaging is implemented by hybrid galvanometer and mechanical scanning. To allow fast B-scan measurements, scanning of the interrogation beam along one dimension is executed by a galvanometer scanner. Slow-axis scanning, perpendicular to the fast axis, is performed utilizing a linear translational stage. We demonstrate two-dimensional and three-dimensional imaging on agarose phantoms. PMID:25900968

  18. Dual Modality Noncontact Photoacoustic and Spectral Domain OCT Imaging.

    PubMed

    Leiss-Holzinger, Elisabeth; Bauer-Marschallinger, Johannes; Hochreiner, Armin; Hollinger, Philipp; Berer, Thomas

    2016-01-01

    We developed a multimodal imaging system, combining noncontact photoacoustic imaging and optical coherence tomography (OCT). Photoacoustic signals are recorded without contact to the specimens' surface by using an interferometric technique. The interferometer is realized within a fiber-optic network using a fiber laser at 1550 nm as source. The fiber-optic network allows the integration of a fiber-based OCT system operating at a wavelength region around 1310 nm. Light from the fiber laser and the OCT source are multiplexed into one fiber using wavelength-division multiplexing. The same focusing optics is used for both modalities. Back-reflected light from the sample is demultiplexed and guided to the respective imaging systems. As the same optical components are used for OCT and photoacoustic imaging, the obtained images are co-registered intrinsically in lateral direction. Three-dimensional imaging is implemented by hybrid galvanometer and mechanical scanning. To allow fast B-scan measurements, scanning of the interrogation beam along one dimension is executed by a galvanometer scanner. Slow-axis scanning, perpendicular to the fast axis, is performed utilizing a linear translational stage. We demonstrate two-dimensional and three-dimensional imaging on agarose phantoms.

  19. Advanced Imaging Modalities in the Detection of Cerebral Vasospasm

    PubMed Central

    Mills, Jena N.; Mehta, Vivek; Russin, Jonathan; Amar, Arun P.; Rajamohan, Anandh; Mack, William J.

    2013-01-01

    The pathophysiology of cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) is complex and is not entirely understood. Mechanistic insights have been gained through advances in the capabilities of diagnostic imaging. Core techniques have focused on the assessment of vessel caliber, tissue metabolism, and/or regional perfusion parameters. Advances in imaging have provided clinicians with a multifaceted approach to assist in the detection of cerebral vasospasm and the diagnosis of delayed ischemic neurologic deficits (DIND). However, a single test or algorithm with broad efficacy remains elusive. This paper examines both anatomical and physiological imaging modalities applicable to post-SAH vasospasm and offers a historical background. We consider cerebral blood flow velocities measured by Transcranial Doppler Ultrasonography (TCD). Structural imaging techniques, including catheter-based Digital Subtraction Angiography (DSA), CT Angiography (CTA), and MR Angiography (MRA), are reviewed. We examine physiologic assessment by PET, HMPAO SPECT, 133Xe Clearance, Xenon-Enhanced CT (Xe/CT), Perfusion CT (PCT), and Diffusion-Weighted/MR Perfusion Imaging. Comparative advantages and limitations are discussed. PMID:23476766

  20. Improved proton computed tomography by dual modality image reconstruction

    SciTech Connect

    Hansen, David C. Bassler, Niels; Petersen, Jørgen Breede Baltzer; Sørensen, Thomas Sangild

    2014-03-15

    Purpose: Proton computed tomography (CT) is a promising image modality for improving the stopping power estimates and dose calculations for particle therapy. However, the finite range of about 33 cm of water of most commercial proton therapy systems limits the sites that can be scanned from a full 360° rotation. In this paper the authors propose a method to overcome the problem using a dual modality reconstruction (DMR) combining the proton data with a cone-beam x-ray prior. Methods: A Catphan 600 phantom was scanned using a cone beam x-ray CT scanner. A digital replica of the phantom was created in the Monte Carlo code Geant4 and a 360° proton CT scan was simulated, storing the entrance and exit position and momentum vector of every proton. Proton CT images were reconstructed using a varying number of angles from the scan. The proton CT images were reconstructed using a constrained nonlinear conjugate gradient algorithm, minimizing total variation and the x-ray CT prior while remaining consistent with the proton projection data. The proton histories were reconstructed along curved cubic-spline paths. Results: The spatial resolution of the cone beam CT prior was retained for the fully sampled case and the 90° interval case, with the MTF = 0.5 (modulation transfer function) ranging from 5.22 to 5.65 linepairs/cm. In the 45° interval case, the MTF = 0.5 dropped to 3.91 linepairs/cm For the fully sampled DMR, the maximal root mean square (RMS) error was 0.006 in units of relative stopping power. For the limited angle cases the maximal RMS error was 0.18, an almost five-fold improvement over the cone beam CT estimate. Conclusions: Dual modality reconstruction yields the high spatial resolution of cone beam x-ray CT while maintaining the improved stopping power estimation of proton CT. In the case of limited angles, the use of prior image proton CT greatly improves the resolution and stopping power estimate, but does not fully achieve the quality of a 360

  1. Multi-modal molecular diffuse optical tomography system for small animal imaging

    PubMed Central

    Guggenheim, James A.; Basevi, Hector R. A.; Frampton, Jon; Styles, Iain B.; Dehghani, Hamid

    2013-01-01

    A multi-modal optical imaging system for quantitative 3D bioluminescence and functional diffuse imaging is presented, which has no moving parts and uses mirrors to provide multi-view tomographic data for image reconstruction. It is demonstrated that through the use of trans-illuminated spectral near infrared measurements and spectrally constrained tomographic reconstruction, recovered concentrations of absorbing agents can be used as prior knowledge for bioluminescence imaging within the visible spectrum. Additionally, the first use of a recently developed multi-view optical surface capture technique is shown and its application to model-based image reconstruction and free-space light modelling is demonstrated. The benefits of model-based tomographic image recovery as compared to 2D planar imaging are highlighted in a number of scenarios where the internal luminescence source is not visible or is confounding in 2D images. The results presented show that the luminescence tomographic imaging method produces 3D reconstructions of individual light sources within a mouse-sized solid phantom that are accurately localised to within 1.5mm for a range of target locations and depths indicating sensitivity and accurate imaging throughout the phantom volume. Additionally the total reconstructed luminescence source intensity is consistent to within 15% which is a dramatic improvement upon standard bioluminescence imaging. Finally, results from a heterogeneous phantom with an absorbing anomaly are presented demonstrating the use and benefits of a multi-view, spectrally constrained coupled imaging system that provides accurate 3D luminescence images. PMID:24954977

  2. Multi-modal imaging and cancer therapy using lanthanide oxide nanoparticles: current status and perspectives.

    PubMed

    Park, J Y; Chang, Y; Lee, G H

    2015-01-01

    Biomedical imaging is an essential tool for diagnosis and therapy of diseases such as cancers. It is likely true that medicine has developed with biomedical imaging methods. Sensitivity and resolution of biomedical imaging methods can be improved with imaging agents. Furthermore, it will be ideal if imaging agents could be also used as therapeutic agents. Therefore, one dose can be used for both diagnosis and therapy of diseases (i.e., theragnosis). This will simplify medical treatment of diseases, and will be also a benefit to patients. Mixed (Ln(1x)Ln(2y)O3, x + y = 2) or unmixed (Ln2O3) lanthanide (Ln) oxide nanoparticles (Ln = Eu, Gd, Dy, Tb, Ho, Er) are potential multi-modal imaging and cancer therapeutic agents. The lanthanides have a variety of magnetic and optical properties, useful for magnetic resonance imaging (MRI) and fluorescent imaging (FI), respectively. They also highly attenuate X-ray beam, useful for X-ray computed tomography (CT). In addition gadolinium-157 ((157)Gd) has the highest thermal neutron capture cross section among stable radionuclides, useful for gadolinium neutron capture therapy (GdNCT). Therefore, mixed or unmixed lanthanide oxide nanoparticles can be used for multi-modal imaging methods (i.e., MRI-FI, MRI-CT, CT-FI, and MRICT- FI) and cancer therapy (i.e., GdNCT). Since mixed or unmixed lanthanide oxide nanoparticles are single-phase and solid-state, they can be easily synthesized, and are compact and robust, which will be beneficial to biomedical applications. In this review physical properties of the lanthanides, synthesis, characterizations, multi-modal imagings, and cancer therapy of mixed and unmixed lanthanide oxide nanoparticles are discussed.

  3. Cumulative phase delay imaging - A new contrast enhanced ultrasound modality

    SciTech Connect

    Demi, Libertario Sloun, Ruud J. G. van; Mischi, Massimo; Wijkstra, Hessel

    2015-10-28

    Recently, a new acoustic marker for ultrasound contrast agents (UCAs) has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental pressure wave field components is in fact observable for ultrasound propagating through UCAs. This phenomenon is absent in the case of tissue nonlinearity and is dependent on insonating pressure and frequency, UCA concentration, and propagation path length through UCAs. In this paper, ultrasound images based on this marker are presented. The ULA-OP research platform, in combination with a LA332 linear array probe (Esaote, Firenze Italy), were used to image a gelatin phantom containing a PVC plate (used as a reflector) and a cylindrical cavity measuring 7 mm in diameter (placed in between the observation point and the PVC plate). The cavity contained a 240 µL/L SonoVueO{sup ®} UCA concentration. Two insonating frequencies (3 MHz and 2.5 MHz) were used to scan the gelatine phantom. A mechanical index MI = 0.07, measured in water at the cavity location with a HGL-0400 hydrophone (Onda, Sunnyvale, CA), was utilized. Processing the ultrasound signals backscattered from the plate, ultrasound images were generated in a tomographic fashion using the filtered back-projection method. As already observed in previous studies, significantly higher CPD values are measured when imaging at a frequency of 2.5 MHz, as compared to imaging at 3 MHz. In conclusion, these results confirm the applicability of the discussed CPD as a marker for contrast imaging. Comparison with standard contrast-enhanced ultrasound imaging modalities will be the focus of future work.

  4. Cumulative phase delay imaging - A new contrast enhanced ultrasound modality

    NASA Astrophysics Data System (ADS)

    Demi, Libertario; van Sloun, Ruud J. G.; Wijkstra, Hessel; Mischi, Massimo

    2015-10-01

    Recently, a new acoustic marker for ultrasound contrast agents (UCAs) has been introduced. A cumulative phase delay (CPD) between the second harmonic and fundamental pressure wave field components is in fact observable for ultrasound propagating through UCAs. This phenomenon is absent in the case of tissue nonlinearity and is dependent on insonating pressure and frequency, UCA concentration, and propagation path length through UCAs. In this paper, ultrasound images based on this marker are presented. The ULA-OP research platform, in combination with a LA332 linear array probe (Esaote, Firenze Italy), were used to image a gelatin phantom containing a PVC plate (used as a reflector) and a cylindrical cavity measuring 7 mm in diameter (placed in between the observation point and the PVC plate). The cavity contained a 240 µL/L SonoVueO® UCA concentration. Two insonating frequencies (3 MHz and 2.5 MHz) were used to scan the gelatine phantom. A mechanical index MI = 0.07, measured in water at the cavity location with a HGL-0400 hydrophone (Onda, Sunnyvale, CA), was utilized. Processing the ultrasound signals backscattered from the plate, ultrasound images were generated in a tomographic fashion using the filtered back-projection method. As already observed in previous studies, significantly higher CPD values are measured when imaging at a frequency of 2.5 MHz, as compared to imaging at 3 MHz. In conclusion, these results confirm the applicability of the discussed CPD as a marker for contrast imaging. Comparison with standard contrast-enhanced ultrasound imaging modalities will be the focus of future work.

  5. Deep convolutional neural networks for multi-modality isointense infant brain image segmentation.

    PubMed

    Zhang, Wenlu; Li, Rongjian; Deng, Houtao; Wang, Li; Lin, Weili; Ji, Shuiwang; Shen, Dinggang

    2015-03-01

    The segmentation of infant brain tissue images into white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF) plays an important role in studying early brain development in health and disease. In the isointense stage (approximately 6-8 months of age), WM and GM exhibit similar levels of intensity in both T1 and T2 MR images, making the tissue segmentation very challenging. Only a small number of existing methods have been designed for tissue segmentation in this isointense stage; however, they only used a single T1 or T2 images, or the combination of T1 and T2 images. In this paper, we propose to use deep convolutional neural networks (CNNs) for segmenting isointense stage brain tissues using multi-modality MR images. CNNs are a type of deep models in which trainable filters and local neighborhood pooling operations are applied alternatingly on the raw input images, resulting in a hierarchy of increasingly complex features. Specifically, we used multi-modality information from T1, T2, and fractional anisotropy (FA) images as inputs and then generated the segmentation maps as outputs. The multiple intermediate layers applied convolution, pooling, normalization, and other operations to capture the highly nonlinear mappings between inputs and outputs. We compared the performance of our approach with that of the commonly used segmentation methods on a set of manually segmented isointense stage brain images. Results showed that our proposed model significantly outperformed prior methods on infant brain tissue segmentation. In addition, our results indicated that integration of multi-modality images led to significant performance improvement.

  6. Imaging Modality of Choice for Pre-Operative Cochlear Imaging: HRCT vs. MRI Temporal Bone

    PubMed Central

    Solanki, Rajendra N.; Shah, Dipali C.; Vishwakarma, Rajesh; Kumar, Sandeep

    2016-01-01

    Introduction Congenital inner ear malformations occur as a result of the arrest or aberrance of inner ear development due to the heredity, gene mutation or other factors. Ever since the availability of cochlear implants, pre-operative evaluation by imaging of temporal bone has gained much attention. Precise selection of the candidate for cochlear implant dependent on preoperative radiological investigations. Only CT (Computed Tomography) and MRI (Magnetic Resonance Imaging) can provide a better picture of anatomy and pathology. Aim To compare pre-operative imaging findings of both MRI and High Resolution Computed Tomography (HRCT) temporal bone and to find the best modality of choice in patients with bilateral profound Sensorineural Hearing Loss (SNHL). Materials and Methods This was a prospective, longitudinal, observational study conducted between June 2010 to November 2012. A total of 144 temporal bones were evaluated in 72 children with bilateral profound SNHL with congenital inner ear malformations. Each temporal bone was considered as a single case (144 cases). All the patients underwent HRCT and high field MRI study. MRI study included T2 W axial 3D FIESTA (Fast Imaging Employing Steady-state Acquisition) sequence. Anatomic abnormalities in each temporal bone were described and noted. For complete and better evaluation of Vestibulo-Cochlear Nerve (VCN) additional 3D oblique parasagittal view was taken perpendicular to the internal auditory canal with a small Field Of View (FOV). Results HRCT and MRI allowed accurate detection of inner ear malformations in children with bilateral SNHL. Majority of the patients presented with multiple structural abnormalities of inner ear. The common pathologies detected in the study were semicircular canal abnormality (89/144) followed by cochlear abnormalities (39/144). Most common cochlear abnormality was Mondini’s deformity (14/144). MRI demonstrated absent of vestibulo-cochlear nerve in 15 cases. Conclusion Few

  7. Use of multiple imaging modalities to detect ovarian cancer

    NASA Astrophysics Data System (ADS)

    Kanter, Elizabeth; Walker, Ross; Marion, Sam; Hoyer, Patricia; Barton, Jennifer K.

    2005-04-01

    Ovarian cancer is not a common cancer-approximately 25,000 new cases in 2004-but it is the fifth leading cause of death from cancer in women (over 16,000 in 2004). Little is known about the precursors and early stages of ovarian cancer partially due to the lack of human samples at the early stages. A cohesive model that incorporates ovarian cancer induction into a menopausal rodent would be well suited for comprehensive studies of ovarian cancer. Non-destructive imaging would allow carcinogenesis to be followed. Optical Coherence Tomography (OCT), Optical Coherence Microscopy (OCM) and Light-Induced Fluorescence (LIF) are minimally invasive optical modalities that allow both structural and biochemical changes to be noted. Rat ovaries were exposed to 4-vinylcyclohexene diepoxide (VCD) for 20 days in order to destroy the primordial follicles. Plain sutures and sutures coated with 7,12-dimethylbenz(a)anthracene (DMBA) were implanted in the right ovary, in order to produce epithelial based ovarian cancers (a plain suture was inserted in the control). Rats were sacrificed at 4 weeks and ovaries were harvested and imaged with a combined OCT/LIF system and with the OCM. Histology was preformed on the harvested ovaries and any pathology determined. Two of the ovaries were visually abnormal; the OCT/LIF imaging confirmed these abnormalities. The normal ovary OCM and OCT images show the organized structure of the ovary, the follicles, bursa and corpus lutea are visible. The OCM images show the disorganized structure of one of the abnormal ovaries. Overall this pilot study demonstrated the feasibility of both the animal model and optical imaging.

  8. Imaging Modalities to Identity Inflammation in an Atherosclerotic Plaque

    PubMed Central

    Goel, Sunny; Miller, Avraham; Agarwal, Chirag; Zakin, Elina; Acholonu, Michael; Gidwani, Umesh; Sharma, Abhishek; Kulbak, Guy; Shani, Jacob; Chen, On

    2015-01-01

    Atherosclerosis is a chronic, progressive, multifocal arterial wall disease caused by local and systemic inflammation responsible for major cardiovascular complications such as myocardial infarction and stroke. With the recent understanding that vulnerable plaque erosion and rupture, with subsequent thrombosis, rather than luminal stenosis, is the underlying cause of acute ischemic events, there has been a shift of focus to understand the mechanisms that make an atherosclerotic plaque unstable or vulnerable to rupture. The presence of inflammation in the atherosclerotic plaque has been considered as one of the initial events which convert a stable plaque into an unstable and vulnerable plaque. This paper systemically reviews the noninvasive and invasive imaging modalities that are currently available to detect this inflammatory process, at least in the intermediate stages, and discusses the ongoing studies that will help us to better understand and identify it at the molecular level. PMID:26798515

  9. Using image synthesis for multi-channel registration of different image modalities.

    PubMed

    Chen, Min; Jog, Amod; Carass, Aaron; Prince, Jerry L

    2015-02-21

    This paper presents a multi-channel approach for performing registration between magnetic resonance (MR) images with different modalities. In general, a multi-channel registration cannot be used when the moving and target images do not have analogous modalities. In this work, we address this limitation by using a random forest regression technique to synthesize the missing modalities from the available ones. This allows a single channel registration between two different modalities to be converted into a multi-channel registration with two mono-modal channels. To validate our approach, two openly available registration algorithms and five cost functions were used to compare the label transfer accuracy of the registration with (and without) our multi-channel synthesis approach. Our results show that the proposed method produced statistically significant improvements in registration accuracy (at an α level of 0.001) for both algorithms and all cost functions when compared to a standard multi-modal registration using the same algorithms with mutual information.

  10. Medical students' knowledge of indications for imaging modalities and cost analysis of incorrect requests, shiraz, iran 2011-2012.

    PubMed

    Islami Parkoohi, Parisa; Jalli, Reza; Danaei, Mina; Khajavian, Shiva; Askarian, Mehrdad

    2014-05-01

    Medical imaging has a remarkable role in the practice of clinical medicine. This study intends to evaluate the knowledge of indications of five common medical imaging modalities and estimation of the imposed cost of their non-indicated requests among medical students who attend Shiraz University of Medical Sciences, Shiraz, Iran. We conducted across-sectional survey using a self-administered questionnaire to assess the knowledge of indications of a number of medical imaging modalities among 270 medical students during their externship or internship periods. Knowledge scoring was performed according to a descriptive international grade conversion (fail to excellent) using Iranian academic grading (0 to 20). In addition, we estimated the cost for incorrect selection of those modalities according to public and private tariffs in US dollars. The participation and response rate was 200/270 (74%). The mean knowledge score was fair for all modalities. Similar scores were excellent for X-ray, acceptable for Doppler ultrasonography, and fair for ultrasonography, CT scan and MRI. The total cost for non-indicated requests of those modalities equaled $104303 (public tariff) and $205581 (private tariff). Medical students at Shiraz University of Medical Sciences lacked favorable knowledge about indications for common medical imaging modalities. The results of this study have shown a significant cost for non-indicated requests of medical imaging. Of note, the present radiology curriculum is in need of a major revision with regards to evidence-based radiology and health economy concerns.

  11. Precise diagnosis in different scenarios using photoacoustic and fluorescence imaging with dual-modality nanoparticles

    NASA Astrophysics Data System (ADS)

    Peng, Dong; Du, Yang; Shi, Yiwen; Mao, Duo; Jia, Xiaohua; Li, Hui; Zhu, Yukun; Wang, Kun; Tian, Jie

    2016-07-01

    Photoacoustic imaging and fluorescence molecular imaging are emerging as important research tools for biomedical studies. Photoacoustic imaging offers both strong optical absorption contrast and high ultrasonic resolution, and fluorescence molecular imaging provides excellent superficial resolution, high sensitivity, high throughput, and the ability for real-time imaging. Therefore, combining the imaging information of both modalities can provide comprehensive in vivo physiological and pathological information. However, currently there are limited probes available that can realize both fluorescence and photoacoustic imaging, and advanced biomedical applications for applying this dual-modality imaging approach remain underexplored. In this study, we developed a dual-modality photoacoustic-fluorescence imaging nanoprobe, ICG-loaded Au@SiO2, which was uniquely designed, consisting of gold nanorod cores and indocyanine green with silica shell spacer layers to overcome fluorophore quenching. This nanoprobe was examined by both PAI and FMI for in vivo imaging on tumor and ischemia mouse models. Our results demonstrated that the nanoparticles can specifically accumulate at the tumor and ischemic areas and be detected by both imaging modalities. Moreover, this dual-modality imaging strategy exhibited superior advantages for a precise diagnosis in different scenarios. The new nanoprobe with the dual-modality imaging approach holds great potential for diagnosis and stage classification of tumor and ischemia related diseases.Photoacoustic imaging and fluorescence molecular imaging are emerging as important research tools for biomedical studies. Photoacoustic imaging offers both strong optical absorption contrast and high ultrasonic resolution, and fluorescence molecular imaging provides excellent superficial resolution, high sensitivity, high throughput, and the ability for real-time imaging. Therefore, combining the imaging information of both modalities can provide

  12. The integration of quantitative multi-modality imaging data into mathematical models of tumors

    NASA Astrophysics Data System (ADS)

    Atuegwu, Nkiruka C.; Gore, John C.; Yankeelov, Thomas E.

    2010-05-01

    Quantitative imaging data obtained from multiple modalities may be integrated into mathematical models of tumor growth and treatment response to achieve additional insights of practical predictive value. We show how this approach can describe the development of tumors that appear realistic in terms of producing proliferating tumor rims and necrotic cores. Two established models (the logistic model with and without the effects of treatment) and one novel model built a priori from available imaging data have been studied. We modify the logistic model to predict the spatial expansion of a tumor driven by tumor cell migration after a voxel's carrying capacity has been reached. Depending on the efficacy of a simulated cytoxic treatment, we show that the tumor may either continue to expand, or contract. The novel model includes hypoxia as a driver of tumor cell movement. The starting conditions for these models are based on imaging data related to the tumor cell number (as estimated from diffusion-weighted MRI), apoptosis (from 99mTc-Annexin-V SPECT), cell proliferation and hypoxia (from PET). We conclude that integrating multi-modality imaging data into mathematical models of tumor growth is a promising combination that can capture the salient features of tumor growth and treatment response and this indicates the direction for additional research.

  13. Lipid-coated iron oxide nanoparticles for dual-modal imaging of hepatocellular carcinoma

    PubMed Central

    Liang, Jinying; Zhang, Xinxin; Miao, Yunqiu; Li, Juan; Gan, Yong

    2017-01-01

    The development of noninvasive imaging techniques for the accurate diagnosis of progressive hepatocellular carcinoma (HCC) is of great clinical significance and has always been desired. Herein, a hepatocellular carcinoma cell-targeting fluorescent magnetic nanoparticle (NP) was obtained by conjugating near-infrared fluorescence to the surface of Fe3O4 (NIRF-Fe3O4) NPs, followed by coating the lipids consisting of tumoral hepatocytes-targeting polymer (Gal-P123). This magnetic NP (GPC@NIRF-Fe3O4) with superparamagnetic behavior showed high stability and safety in physiological conditions. In addition, GPC@NIRF-Fe3O4 achieved more specific uptake of human liver cancer cells than free Fe3O4 NPs. Importantly, with superpara-magnetic iron oxide and strong NIR absorbance, GPC@NIRF-Fe3O4 NPs demonstrate prominent tumor-contrasted imaging performance both on fluorescent and T2-weighted magnetic resonance (MR) imaging modalities in a living body. The relative MR signal enhancement of GPC@NIRF-Fe3O4 NPs achieved 5.4-fold improvement compared with NIR-Fe3O4 NPs. Therefore, GPC@ NIRF-Fe3O4 NPs may be potentially used as a candidate for dual-modal imaging of tumors with information covalidated and directly compared by combining fluorescence and MR imaging. PMID:28352173

  14. Deep Convolutional Neural Networks for Multi-Modality Isointense Infant Brain Image Segmentation

    PubMed Central

    Zhang, Wenlu; Li, Rongjian; Deng, Houtao; Wang, Li; Lin, Weili; Ji, Shuiwang; Shen, Dinggang

    2015-01-01

    The segmentation of infant brain tissue images into white matter (WM), gray matter (GM), and cerebrospinal fluid (CSF) plays an important role in studying early brain development in health and disease. In the isointense stage (approximately 6–8 months of age), WM and GM exhibit similar levels of intensity in both T1 and T2 MR images, making the tissue segmentation very challenging. Only a small number of existing methods have been designed for tissue segmentation in this isointense stage; however, they only used a single T1 or T2 images, or the combination of T1 and T2 images. In this paper, we propose to use deep convolutional neural networks (CNNs) for segmenting isointense stage brain tissues using multi-modality MR images. CNNs are a type of deep models in which trainable filters and local neighborhood pooling operations are applied alternatingly on the raw input images, resulting in a hierarchy of increasingly complex features. Specifically, we used multimodality information from T1, T2, and fractional anisotropy (FA) images as inputs and then generated the segmentation maps as outputs. The multiple intermediate layers applied convolution, pooling, normalization, and other operations to capture the highly nonlinear mappings between inputs and outputs. We compared the performance of our approach with that of the commonly used segmentation methods on a set of manually segmented isointense stage brain images. Results showed that our proposed model significantly outperformed prior methods on infant brain tissue segmentation. In addition, our results indicated that integration of multi-modality images led to significant performance improvement. PMID:25562829

  15. How Can New Imaging Modalities Help in the Practice of Radiology?

    PubMed Central

    Pirimoglu, Berhan; Sade, Recep; Ogul, Hayri; Kantarci, Mecit; Eren, Suat; Levent, Akın

    2016-01-01

    The purpose of this article was to provide an up-to-date review on the spectrum of new imaging applications in the practice of radiology. New imaging techniques have been developed with the objective of obtaining structural and functional analyses of different body systems. Recently, new imaging modalities have aroused the interest of many researchers who are studying the applicability of these modalities in the evaluation of different organs and diseases. In this review article, we present the efficiency and utilization of current imaging modalities in daily radiological practice. PMID:28149149

  16. How Can New Imaging Modalities Help in the Practice of Radiology?

    PubMed

    Pirimoglu, Berhan; Sade, Recep; Ogul, Hayri; Kantarci, Mecit; Eren, Suat; Levent, Akın

    2016-10-01

    The purpose of this article was to provide an up-to-date review on the spectrum of new imaging applications in the practice of radiology. New imaging techniques have been developed with the objective of obtaining structural and functional analyses of different body systems. Recently, new imaging modalities have aroused the interest of many researchers who are studying the applicability of these modalities in the evaluation of different organs and diseases. In this review article, we present the efficiency and utilization of current imaging modalities in daily radiological practice.

  17. EVolution: an edge-based variational method for non-rigid multi-modal image registration

    NASA Astrophysics Data System (ADS)

    de Senneville, B. Denis; Zachiu, C.; Ries, M.; Moonen, C.

    2016-10-01

    Image registration is part of a large variety of medical applications including diagnosis, monitoring disease progression and/or treatment effectiveness and, more recently, therapy guidance. Such applications usually involve several imaging modalities such as ultrasound, computed tomography, positron emission tomography, x-ray or magnetic resonance imaging, either separately or combined. In the current work, we propose a non-rigid multi-modal registration method (namely EVolution: an edge-based variational method for non-rigid multi-modal image registration) that aims at maximizing edge alignment between the images being registered. The proposed algorithm requires only contrasts between physiological tissues, preferably present in both image modalities, and assumes deformable/elastic tissues. Given both is shown to be well suitable for non-rigid co-registration across different image types/contrasts (T1/T2) as well as different modalities (CT/MRI). This is achieved using a variational scheme that provides a fast algorithm with a low number of control parameters. Results obtained on an annotated CT data set were comparable to the ones provided by state-of-the-art multi-modal image registration algorithms, for all tested experimental conditions (image pre-filtering, image intensity variation, noise perturbation). Moreover, we demonstrate that, compared to existing approaches, our method possesses increased robustness to transient structures (i.e. that are only present in some of the images).

  18. A novel automated method for doing registration and 3D reconstruction from multi-modal RGB/IR image sequences

    NASA Astrophysics Data System (ADS)

    Kirby, Richard; Whitaker, Ross

    2016-09-01

    In recent years, the use of multi-modal camera rigs consisting of an RGB sensor and an infrared (IR) sensor have become increasingly popular for use in surveillance and robotics applications. The advantages of using multi-modal camera rigs include improved foreground/background segmentation, wider range of lighting conditions under which the system works, and richer information (e.g. visible light and heat signature) for target identification. However, the traditional computer vision method of mapping pairs of images using pixel intensities or image features is often not possible with an RGB/IR image pair. We introduce a novel method to overcome the lack of common features in RGB/IR image pairs by using a variational methods optimization algorithm to map the optical flow fields computed from different wavelength images. This results in the alignment of the flow fields, which in turn produce correspondences similar to those found in a stereo RGB/RGB camera rig using pixel intensities or image features. In addition to aligning the different wavelength images, these correspondences are used to generate dense disparity and depth maps. We obtain accuracies similar to other multi-modal image alignment methodologies as long as the scene contains sufficient depth variations, although a direct comparison is not possible because of the lack of standard image sets from moving multi-modal camera rigs. We test our method on synthetic optical flow fields and on real image sequences that we created with a multi-modal binocular stereo RGB/IR camera rig. We determine our method's accuracy by comparing against a ground truth.

  19. single-channel stereoscopic video imaging modality based on a transparent rotating deflector

    NASA Astrophysics Data System (ADS)

    Radfar, Edalat; Park, Jihoon; Jun, Eunkwon; Ha, Myungjin; Lee, Sangyeob; Yu, SungKon; Jang, Seul G.; Jung, Byungjo

    2015-03-01

    This paper introduces a stereoscopic video imaging modality based on a transparent rotating deflector (TRD). Sequential two-dimensional (2D) left and right images were obtained by rotating the TRD on a stepping motor synchronized with a complementary metal-oxide semiconductor camera, and the components of the imaging modality were controlled through general purpose input/output ports using a microcontroller unit. In this research, live stereoscopic videos were visualized on a personal computer by both active shutter 3D and passive polarization 3D methods. The imaging modality was characterized by evaluating the stereoscopic video image generation, rotation characteristics of the TRD. The level of 3D conception was estimated in terms of simplified human stereovision. The results show that singlechannel stereoscopic video imaging modality has the potential to become an economical compact stereoscopic device as the system components are amenable to miniaturization; and could be applied in a wide variety of fields.

  20. VoxelStats: A MATLAB Package for Multi-Modal Voxel-Wise Brain Image Analysis.

    PubMed

    Mathotaarachchi, Sulantha; Wang, Seqian; Shin, Monica; Pascoal, Tharick A; Benedet, Andrea L; Kang, Min Su; Beaudry, Thomas; Fonov, Vladimir S; Gauthier, Serge; Labbe, Aurélie; Rosa-Neto, Pedro

    2016-01-01

    In healthy individuals, behavioral outcomes are highly associated with the variability on brain regional structure or neurochemical phenotypes. Similarly, in the context of neurodegenerative conditions, neuroimaging reveals that cognitive decline is linked to the magnitude of atrophy, neurochemical declines, or concentrations of abnormal protein aggregates across brain regions. However, modeling the effects of multiple regional abnormalities as determinants of cognitive decline at the voxel level remains largely unexplored by multimodal imaging research, given the high computational cost of estimating regression models for every single voxel from various imaging modalities. VoxelStats is a voxel-wise computational framework to overcome these computational limitations and to perform statistical operations on multiple scalar variables and imaging modalities at the voxel level. VoxelStats package has been developed in Matlab(®) and supports imaging formats such as Nifti-1, ANALYZE, and MINC v2. Prebuilt functions in VoxelStats enable the user to perform voxel-wise general and generalized linear models and mixed effect models with multiple volumetric covariates. Importantly, VoxelStats can recognize scalar values or image volumes as response variables and can accommodate volumetric statistical covariates as well as their interaction effects with other variables. Furthermore, this package includes built-in functionality to perform voxel-wise receiver operating characteristic analysis and paired and unpaired group contrast analysis. Validation of VoxelStats was conducted by comparing the linear regression functionality with existing toolboxes such as glim_image and RMINC. The validation results were identical to existing methods and the additional functionality was demonstrated by generating feature case assessments (t-statistics, odds ratio, and true positive rate maps). In summary, VoxelStats expands the current methods for multimodal imaging analysis by allowing the

  1. VoxelStats: A MATLAB Package for Multi-Modal Voxel-Wise Brain Image Analysis

    PubMed Central

    Mathotaarachchi, Sulantha; Wang, Seqian; Shin, Monica; Pascoal, Tharick A.; Benedet, Andrea L.; Kang, Min Su; Beaudry, Thomas; Fonov, Vladimir S.; Gauthier, Serge; Labbe, Aurélie; Rosa-Neto, Pedro

    2016-01-01

    In healthy individuals, behavioral outcomes are highly associated with the variability on brain regional structure or neurochemical phenotypes. Similarly, in the context of neurodegenerative conditions, neuroimaging reveals that cognitive decline is linked to the magnitude of atrophy, neurochemical declines, or concentrations of abnormal protein aggregates across brain regions. However, modeling the effects of multiple regional abnormalities as determinants of cognitive decline at the voxel level remains largely unexplored by multimodal imaging research, given the high computational cost of estimating regression models for every single voxel from various imaging modalities. VoxelStats is a voxel-wise computational framework to overcome these computational limitations and to perform statistical operations on multiple scalar variables and imaging modalities at the voxel level. VoxelStats package has been developed in Matlab® and supports imaging formats such as Nifti-1, ANALYZE, and MINC v2. Prebuilt functions in VoxelStats enable the user to perform voxel-wise general and generalized linear models and mixed effect models with multiple volumetric covariates. Importantly, VoxelStats can recognize scalar values or image volumes as response variables and can accommodate volumetric statistical covariates as well as their interaction effects with other variables. Furthermore, this package includes built-in functionality to perform voxel-wise receiver operating characteristic analysis and paired and unpaired group contrast analysis. Validation of VoxelStats was conducted by comparing the linear regression functionality with existing toolboxes such as glim_image and RMINC. The validation results were identical to existing methods and the additional functionality was demonstrated by generating feature case assessments (t-statistics, odds ratio, and true positive rate maps). In summary, VoxelStats expands the current methods for multimodal imaging analysis by allowing the

  2. SU-E-I-83: Error Analysis of Multi-Modality Image-Based Volumes of Rodent Solid Tumors Using a Preclinical Multi-Modality QA Phantom

    SciTech Connect

    Lee, Y; Fullerton, G; Goins, B

    2015-06-15

    Purpose: In our previous study a preclinical multi-modality quality assurance (QA) phantom that contains five tumor-simulating test objects with 2, 4, 7, 10 and 14 mm diameters was developed for accurate tumor size measurement by researchers during cancer drug development and testing. This study analyzed the errors during tumor volume measurement from preclinical magnetic resonance (MR), micro-computed tomography (micro- CT) and ultrasound (US) images acquired in a rodent tumor model using the preclinical multi-modality QA phantom. Methods: Using preclinical 7-Tesla MR, US and micro-CT scanners, images were acquired of subcutaneous SCC4 tumor xenografts in nude rats (3–4 rats per group; 5 groups) along with the QA phantom using the same imaging protocols. After tumors were excised, in-air micro-CT imaging was performed to determine reference tumor volume. Volumes measured for the rat tumors and phantom test objects were calculated using formula V = (π/6)*a*b*c where a, b and c are the maximum diameters in three perpendicular dimensions determined by the three imaging modalities. Then linear regression analysis was performed to compare image-based tumor volumes with the reference tumor volume and known test object volume for the rats and the phantom respectively. Results: The slopes of regression lines for in-vivo tumor volumes measured by three imaging modalities were 1.021, 1.101 and 0.862 for MRI, micro-CT and US respectively. For phantom, the slopes were 0.9485, 0.9971 and 0.9734 for MRI, micro-CT and US respectively. Conclusion: For both animal and phantom studies, random and systematic errors were observed. Random errors were observer-dependent and systematic errors were mainly due to selected imaging protocols and/or measurement method. In the animal study, there were additional systematic errors attributed to ellipsoidal assumption for tumor shape. The systematic errors measured using the QA phantom need to be taken into account to reduce measurement

  3. Evaluation of registration strategies for multi-modality images of rat brain slices

    NASA Astrophysics Data System (ADS)

    Palm, Christoph; Vieten, Andrea; Salber, Dagmar; Pietrzyk, Uwe

    2009-05-01

    In neuroscience, small-animal studies frequently involve dealing with series of images from multiple modalities such as histology and autoradiography. The consistent and bias-free restacking of multi-modality image series is obligatory as a starting point for subsequent non-rigid registration procedures and for quantitative comparisons with positron emission tomography (PET) and other in vivo data. Up to now, consistency between 2D slices without cross validation using an inherent 3D modality is frequently presumed to be close to the true morphology due to the smooth appearance of the contours of anatomical structures. However, in multi-modality stacks consistency is difficult to assess. In this work, consistency is defined in terms of smoothness of neighboring slices within a single modality and between different modalities. Registration bias denotes the distortion of the registered stack in comparison to the true 3D morphology and shape. Based on these metrics, different restacking strategies of multi-modality rat brain slices are experimentally evaluated. Experiments based on MRI-simulated and real dual-tracer autoradiograms reveal a clear bias of the restacked volume despite quantitatively high consistency and qualitatively smooth brain structures. However, different registration strategies yield different inter-consistency metrics. If no genuine 3D modality is available, the use of the so-called SOP (slice-order preferred) or MOSOP (modality-and-slice-order preferred) strategy is recommended.

  4. Gold nanoclusters as contrast agents for fluorescent and X-ray dual-modality imaging.

    PubMed

    Zhang, Aili; Tu, Yu; Qin, Songbing; Li, Yan; Zhou, Juying; Chen, Na; Lu, Qiang; Zhang, Bingbo

    2012-04-15

    Multimodal imaging technique is an alternative approach to improve sensitivity of early cancer diagnosis. In this study, highly fluorescent and strong X-ray absorption coefficient gold nanoclusters (Au NCs) are synthesized as dual-modality imaging contrast agents (CAs) for fluorescent and X-ray dual-modality imaging. The experimental results show that the as-prepared Au NCs are well constructed with ultrasmall sizes, reliable fluorescent emission, high computed tomography (CT) value and fine biocompatibility. In vivo imaging results indicate that the obtained Au NCs are capable of fluorescent and X-ray enhanced imaging.

  5. Hierarchical Multi-modal Image Registration by Learning Common Feature Representations

    PubMed Central

    Ge, Hongkun; Wu, Guorong; Wang, Li; Gao, Yaozong

    2016-01-01

    Mutual information (MI) has been widely used for registering images with different modalities. Since most inter-modality registration methods simply estimate deformations in a local scale, but optimizing MI from the entire image, the estimated deformations for certain structures could be dominated by the surrounding unrelated structures. Also, since there often exist multiple structures in each image, the intensity correlation between two images could be complex and highly nonlinear, which makes global MI unable to precisely guide local image deformation. To solve these issues, we propose a hierarchical inter-modality registration method by robust feature matching. Specifically, we first select a small set of key points at salient image locations to drive the entire image registration. Since the original image features computed from different modalities are often difficult for direct comparison, we propose to learn their common feature representations by projecting them from their native feature spaces to a common space, where the correlations between corresponding features are maximized. Due to the large heterogeneity between two high-dimension feature distributions, we employ Kernel CCA (Canonical Correlation Analysis) to reveal such non-linear feature mappings. Then, our registration method can take advantage of the learned common features to reliably establish correspondences for key points from different modality images by robust feature matching. As more and more key points take part in the registration, our hierarchical feature-based image registration method can efficiently estimate the deformation pathway between two inter-modality images in a global to local manner. We have applied our proposed registration method to prostate CT and MR images, as well as the infant MR brain images in the first year of life. Experimental results show that our method can achieve more accurate registration results, compared to other state-of-the-art image registration

  6. Multi-Modal Curriculum Learning for Semi-Supervised Image Classification.

    PubMed

    Gong, Chen; Tao, Dacheng; Maybank, Stephen J; Liu, Wei; Kang, Guoliang; Yang, Jie

    2016-07-01

    Semi-supervised image classification aims to classify a large quantity of unlabeled images by typically harnessing scarce labeled images. Existing semi-supervised methods often suffer from inadequate classification accuracy when encountering difficult yet critical images, such as outliers, because they treat all unlabeled images equally and conduct classifications in an imperfectly ordered sequence. In this paper, we employ the curriculum learning methodology by investigating the difficulty of classifying every unlabeled image. The reliability and the discriminability of these unlabeled images are particularly investigated for evaluating their difficulty. As a result, an optimized image sequence is generated during the iterative propagations, and the unlabeled images are logically classified from simple to difficult. Furthermore, since images are usually characterized by multiple visual feature descriptors, we associate each kind of features with a teacher, and design a multi-modal curriculum learning (MMCL) strategy to integrate the information from different feature modalities. In each propagation, each teacher analyzes the difficulties of the currently unlabeled images from its own modality viewpoint. A consensus is subsequently reached among all the teachers, determining the currently simplest images (i.e., a curriculum), which are to be reliably classified by the multi-modal learner. This well-organized propagation process leveraging multiple teachers and one learner enables our MMCL to outperform five state-of-the-art methods on eight popular image data sets.

  7. Nano-sensitizers for multi-modality optical diagnostic imaging and therapy of cancer

    NASA Astrophysics Data System (ADS)

    Olivo, Malini; Lucky, Sasidharan S.; Bhuvaneswari, Ramaswamy; Dendukuri, Nagamani

    2011-07-01

    We report novel bioconjugated nanosensitizers as optical and therapeutic probes for the detection, monitoring and treatment of cancer. These nanosensitisers, consisting of hypericin loaded bioconjugated gold nanoparticles, can act as tumor cell specific therapeutic photosensitizers for photodynamic therapy coupled with additional photothermal effects rendered by plasmonic heating effects of gold nanoparticles. In addition to the therapeutic effects, the nanosensitizer can be developed as optical probes for state-of-the-art multi-modality in-vivo optical imaging technology such as in-vivo 3D confocal fluorescence endomicroscopic imaging, optical coherence tomography (OCT) with improved optical contrast using nano-gold and Surface Enhanced Raman Scattering (SERS) based imaging and bio-sensing. These techniques can be used in tandem or independently as in-vivo optical biopsy techniques to specifically detect and monitor specific cancer cells in-vivo. Such novel nanosensitizer based optical biopsy imaging technique has the potential to provide an alternative to tissue biopsy and will enable clinicians to make real-time diagnosis, determine surgical margins during operative procedures and perform targeted treatment of cancers.

  8. Novel "bi-modal" H2dedpa derivatives for radio- and fluorescence imaging.

    PubMed

    Ramogida, Caterina F; Murphy, Lisa; Cawthray, Jacqueline F; Ross, James D; Adam, Michael J; Orvig, Chris

    2016-09-01

    A novel pyridyl functionalized analog of the promising hexadentate (68)Ga(3+) chelate H2dedpa (N4O2, 1,2-[[6-carboxy-pyridin-2-yl]-methylamine]ethane) was successfully synthesized and characterized. This new bifunctional chelate (BFC) was used to prepare the first proof-of-principle bi-modal H2dedpa derivative for fluorescence and nuclear imaging. Two bi-modal H2dedpa derivatives were prepared: H2dedpa-propylpyr-FITC and H2dedpa-propylpyr-FITC-(N,N'-propyl-2-NI) (FITC=fluorescein, pyr=pyridyl functionalized, NI=nitroimidazole). The ligands possess the strong gallium-coordinating atoms contained within dedpa(2-) that are ideal for radiolabeling with (68)Ga(3+) for positron-emission tomography (PET) imaging, and two fluorophores for optical imaging. In addition, one analog contains two NI moieties for specific entrapment of the tracer in hypoxic cells. These new bi-modal analogs were compared to the native unfunctionalized H2dedpa scaffold to determine the extent to which the addition of pyridyl functionalization would affect metal coordination, and complex stability. The non-radioactive gallium complexes were tested in a 3D tumor spheroid model. The novel pyridyl bis-functionalized H2dedpa ligand, H2dedpa-propylpyr-NH2, was quantitatively radiolabeled with (67)Ga (RCY>99%) under reaction conditions commensurate with unfunctionalized H2dedpa (10min at room temperature) at ligand concentrations as low as 10(-5)M. The resultant (67)Ga-complex withstood transchelation to the in vivo metal-binding competitor apo-transferrin (2h at 37°C, 93% intact), signifying that [Ga(dedpa-propylpyr-NH2)](+) is a kinetically inert complex suitable for in vivo use, but exhibited slightly reduced stability compared to the native [(67)Ga(dedpa)] scaffold (>99% intact). Finally, bi-model fluorescent Ga-dedpa compounds were successfully imaged in a 3D tumor spheroid model. The Ga-dedpa-FITC-NI derivative was specifically localized in the central hypoxic core of the spheroid.

  9. Triple-Modal Imaging of Magnetically-Targeted Nanocapsules in Solid Tumours In Vivo

    PubMed Central

    Bai, Jie; Wang, Julie T.-W.; Rubio, Noelia; Protti, Andrea; Heidari, Hamed; Elgogary, Riham; Southern, Paul; Al-Jamal, Wafa' T.; Sosabowski, Jane; Shah, Ajay M.; Bals, Sara; Pankhurst, Quentin A.; Al-Jamal, Khuloud T.

    2016-01-01

    Triple-modal imaging magnetic nanocapsules, encapsulating hydrophobic superparamagnetic iron oxide nanoparticles, are formulated and used to magnetically target solid tumours after intravenous administration in tumour-bearing mice. The engineered magnetic polymeric nanocapsules m-NCs are ~200 nm in size with negative Zeta potential and shown to be spherical in shape. The loading efficiency of superparamagnetic iron oxide nanoparticles in the m-NC was ~100%. Up to ~3- and ~2.2-fold increase in tumour uptake at 1 and 24 h was achieved, when a static magnetic field was applied to the tumour for 1 hour. m-NCs, with multiple imaging probes (e.g. indocyanine green, superparamagnetic iron oxide nanoparticles and indium-111), were capable of triple-modal imaging (fluorescence/magnetic resonance/nuclear imaging) in vivo. Using triple-modal imaging is to overcome the intrinsic limitations of single modality imaging and provides complementary information on the spatial distribution of the nanocarrier within the tumour. The significant findings of this study could open up new research perspectives in using novel magnetically-responsive nanomaterials in magnetic-drug targeting combined with multi-modal imaging. PMID:26909110

  10. Intraoperative Imaging-Guided Cancer Surgery: From Current Fluorescence Molecular Imaging Methods to Future Multi-Modality Imaging Technology

    PubMed Central

    Chi, Chongwei; Du, Yang; Ye, Jinzuo; Kou, Deqiang; Qiu, Jingdan; Wang, Jiandong; Tian, Jie; Chen, Xiaoyuan

    2014-01-01

    Cancer is a major threat to human health. Diagnosis and treatment using precision medicine is expected to be an effective method for preventing the initiation and progression of cancer. Although anatomical and functional imaging techniques such as radiography, computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) have played an important role for accurate preoperative diagnostics, for the most part these techniques cannot be applied intraoperatively. Optical molecular imaging is a promising technique that provides a high degree of sensitivity and specificity in tumor margin detection. Furthermore, existing clinical applications have proven that optical molecular imaging is a powerful intraoperative tool for guiding surgeons performing precision procedures, thus enabling radical resection and improved survival rates. However, detection depth limitation exists in optical molecular imaging methods and further breakthroughs from optical to multi-modality intraoperative imaging methods are needed to develop more extensive and comprehensive intraoperative applications. Here, we review the current intraoperative optical molecular imaging technologies, focusing on contrast agents and surgical navigation systems, and then discuss the future prospects of multi-modality imaging technology for intraoperative imaging-guided cancer surgery. PMID:25250092

  11. Thermophotonic lock-in imaging: a novel early caries detection and imaging modality

    NASA Astrophysics Data System (ADS)

    Tabatabaei, Nima; Mandelis, Andreas; Amaechi, Bennett T.

    2011-03-01

    Using photothermal wave principles and as an extension to the frequency-domain photothermal radiometry, a novel dental imaging modality, thermophotonic lock-in imaging (TPLI), is introduced. In order to assess the capabilities of the proposed methodology samples with natural and artificially-generated caries were examined and the results were compared with the destructive transverse microradiography density profiles. It was found that the increased light scattering and absorption within early carious lesions increases the thermal-wave amplitude and shifts the thermal-wave centroid, producing contrast between the carious lesion and the intact enamel in both amplitude and phase images. Phase images are emissivity normalized and therefore insensitive to the presence of stain. Amplitude images provide integrated information from deeper enamel regions. It was concluded that the results of our non-invasive, non-contacting imaging methodology exhibit significantly higher sensitivity to very early demineralization than dental radiographs and are in agreement with the destructive transverse microradiography mineral density profiles.

  12. Comparison of Ductoscopy, Galactography, and Imaging Modalities for the Evaluation of Intraductal Lesions: A Critical Review

    PubMed Central

    Sarica, Ozgur; Ozturk, Enis; Demirkurek, Huseyin C.; Uluc, Fatih

    2013-01-01

    Summary Background Today, in cases of nipple discharge of unclear origin, the abundance of diagnostic procedures – a, diagnostic dilemma’ – becomes apparent, because unequivocal indications and a current, standardized examination sequence are presently not available. The diagnostic workup of patients with nipple discharge usually includes the clinical history, physical examination, mammography, ultrasonography, galactography, and nipple discharge cytology, but not ductoscopy. Methods In this review we analyze and discuss the possible role of ductoscopy in evaluating intraductal pathologies and its combined use with diagnostic imaging modalities. For this purpose, we reviewed and compared the results of the radiological, pathological, and surgical studies independently. Conclusions Currently, there is no solitary accurate modality to reach our definitive purpose. Being aware of the capability of each diagnostic modality may take us closer to our target. Therefore, adjunct and appropriate use of multiple imaging modalities and ductoscopy is necessary to evaluate patients with nipple discharge. PMID:24415988

  13. Evaluation of 3D modality-independent elastography for breast imaging: a simulation study

    NASA Astrophysics Data System (ADS)

    Ou, J. J.; Ong, R. E.; Yankeelov, T. E.; Miga, M. I.

    2008-01-01

    This paper reports on the development and preliminary testing of a three-dimensional implementation of an inverse problem technique for extracting soft-tissue elasticity information via non-rigid model-based image registration. The modality-independent elastography (MIE) algorithm adjusts the elastic properties of a biomechanical model to achieve maximal similarity between images acquired under different states of static loading. A series of simulation experiments with clinical image sets of human breasts were performed to test the ability of the method to identify and characterize a radiographically occult stiff lesion. Because boundary conditions are a critical input to the algorithm, a comparison of three methods for semi-automated surface point correspondence was conducted in the context of systematic and randomized noise processes. The results illustrate that 3D MIE was able to successfully reconstruct elasticity images using data obtained from both magnetic resonance and x-ray computed tomography systems. The lesion was localized correctly in all cases and its relative elasticity found to be reasonably close to the true values (3.5% with the use of spatial priors and 11.6% without). In addition, the inaccuracies of surface registration performed with thin-plate spline interpolation did not exceed empiric thresholds of unacceptable boundary condition error.

  14. Impact of medical therapy on atheroma volume measured by different cardiovascular imaging modalities.

    PubMed

    Sinno, Mohamad C N; Al-Mallah, Mouaz

    2010-01-01

    Atherosclerosis is a systemic disease that affects most vascular beds. The gold standard of atherosclerosis imaging has been invasive intravascular ultrasound (IVUS). Newer noninvasive imaging modalities like B-mode ultrasound, cardiac computed tomography (CT), positron emission tomography (PET), and magnetic resonance imaging (MRI) have been used to assess these vascular territories with high accuracy and reproducibility. These imaging modalities have lately been used for the assessment of the atherosclerotic plaque and the response of its volume to several medical therapies used in the treatment of patients with cardiovascular disease. To study the impact of these medications on atheroma volume progression or regression, imaging modalities have been used on a serial basis providing a unique opportunity to monitor the effect these antiatherosclerotic strategies exert on plaque burden. As a result, studies incorporating serial IVUS imaging, quantitative coronary angiography (QCA), B-mode ultrasound, electron beam computed tomography (EBCT), and dynamic contrast-enhanced magnetic resonance imaging have all been used to evaluate the impact of therapeutic strategies that modify cholesterol and blood pressure on the progression/regression of atherosclerotic plaque. In this review, we intend to summarize the impact of different therapies aimed at halting the progression or even result in regression of atherosclerotic cardiovascular disease evaluated by different imaging modalities.

  15. Imaging Modalities Relevant to Intracranial Pressure Assessment in Astronauts: A Case-Based Discussion

    NASA Technical Reports Server (NTRS)

    Sargsyan, Ashot E.; Kramer, Larry A.; Hamilton, Douglas R.; Hamilton, Douglas R.; Fogarty, Jennifer; Polk, J. D.

    2010-01-01

    Introduction: Intracranial pressure (ICP) elevation has been inferred or documented in a number of space crewmembers. Recent advances in noninvasive imaging technology offer new possibilities for ICP assessment. Most International Space Station (ISS) partner agencies have adopted a battery of occupational health monitoring tests including magnetic resonance imaging (MRI) pre- and postflight, and high-resolution sonography of the orbital structures in all mission phases including during flight. We hypothesize that joint consideration of data from the two techniques has the potential to improve quality and continuity of crewmember monitoring and care. Methods: Specially designed MRI and sonographic protocols were used to image eyes and optic nerves (ON) including the meningeal sheaths. Specific crewmembers multi-modality imaging data were analyzed to identify points of mutual validation as well as unique features of complementary nature. Results and Conclusion: Magnetic resonance imaging (MRI) and high-resolution sonography are both tomographic methods, however images obtained by the two modalities are based on different physical phenomena and use different acquisition principles. Consideration of the images acquired by these two modalities allows cross-validating findings related to the volume and fluid content of the ON subarachnoid space, shape of the globe, and other anatomical features of the orbit. Each of the imaging modalities also has unique advantages, making them complementary techniques.

  16. Safe storage and multi-modal search for medical images.

    PubMed

    Kommeri, Jukka; Niinimäki, Marko; Müller, Henning

    2011-01-01

    Modern hospitals produce enormous amounts of data in all departments, from images, to lab results, medication use, and release letters. Since several years these data are most often produced in digital form, making them accessible for researchers to optimize the outcome of care process and analyze all available data across patients. The Geneva University Hospitals (HUG) are no exception with its daily radiology department's output of over 140'000 images in 2010, with a majority of them being tomographic slices. In this paper we introduce tools for uploading and accessing DICOM images and associated metadata in a secure Grid storage. These data are made available for authorized persons using a Grid security framework, as security is a main problem in secondary use of image data, where images are to be stored outside of the clinical image archive. Our tool combines the security and metadata access of a Grid middleware with the visual search that uses GIFT.

  17. Programmable aperture microscopy: A computational method for multi-modal phase contrast and light field imaging

    NASA Astrophysics Data System (ADS)

    Zuo, Chao; Sun, Jiasong; Feng, Shijie; Zhang, Minliang; Chen, Qian

    2016-05-01

    We demonstrate a simple and cost-effective programmable aperture microscope to realize multi-modal computational imaging by integrating a programmable liquid crystal display (LCD) into a conventional wide-field microscope. The LCD selectively modulates the light distribution at the rear aperture of the microscope objective, allowing numerous imaging modalities, such as bright field, dark field, differential phase contrast, quantitative phase imaging, multi-perspective imaging, and full resolution light field imaging to be achieved and switched rapidly in the same setup, without requiring specialized hardwares and any moving parts. We experimentally demonstrate the success of our method by imaging unstained cheek cells, profiling microlens array, and changing perspective views of thick biological specimens. The post-exposure refocusing of a butterfly mouthpart and RFP-labeled dicot stem cross-section is also presented to demonstrate the full resolution light field imaging capability of our system for both translucent and fluorescent specimens.

  18. MULTI-MODAL DATA FUSION SCHEMES FOR INTEGRATED CLASSIFICATION OF IMAGING AND NON-IMAGING BIOMEDICAL DATA

    PubMed Central

    Tiwari, Pallavi; Viswanath, Satish; Lee, George; Madabhushi, Anant

    2015-01-01

    With a wide array of multi-modal, multi-protocol, and multi-scale biomedical data available for disease diagnosis and prognosis, there is a need for quantitative tools to combine such varied channels of information, especially imaging and non-imaging data (e.g. spectroscopy, proteomics). The major problem in such quantitative data integration lies in reconciling the large spread in the range of dimensionalities and scales across the different modalities. The primary goal of quantitative data integration is to build combined meta-classifiers; however these efforts are thwarted by challenges in (1) homogeneous representation of the data channels, (2) fusing the attributes to construct an integrated feature vector, and (3) the choice of learning strategy for training the integrated classifier. In this paper, we seek to (a) define the characteristics that guide the 4 independent methods for quantitative data fusion that use the idea of a meta-space for building integrated multi-modal, multi-scale meta-classifiers, and (b) attempt to understand the key components which allowed each method to succeed. These methods include (1) Generalized Embedding Concatenation (GEC), (2) Consensus Embedding (CE), (3) Semi-Supervised Multi-Kernel Graph Embedding (SeSMiK), and (4) Boosted Embedding Combination (BEC). In order to evaluate the optimal scheme for fusing imaging and non-imaging data, we compared these 4 schemes for the problems of combining (a) multi-parametric MRI with spectroscopy for prostate cancer (CaP) diagnosis in vivo, and (b) histological image with proteomic signatures (obtained via mass spectrometry) for predicting prognosis in CaP patients. The kernel combination approach (SeSMiK) marginally outperformed the embedding combination schemes. Additionally, intelligent weighting of the data channels (based on their relative importance) appeared to outperform unweighted strategies. All 4 strategies easily outperformed a naïve decision fusion approach, suggesting that

  19. Multistability, cross-modal binding and the additivity of conjoined grouping principles

    PubMed Central

    Kubovy, Michael; Yu, Minhong

    2012-01-01

    We present a sceptical view of multimodal multistability—drawing most of our examples from the relation between audition and vision. We begin by summarizing some of the principal ways in which audio-visual binding takes place. We review the evidence that unambiguous stimulation in one modality may affect the perception of a multistable stimulus in another modality. Cross-modal influences of one multistable stimulus on the multistability of another are different: they have occurred only in speech perception. We then argue that the strongest relation between perceptual organization in vision and perceptual organization in audition is likely to be by way of analogous Gestalt laws. We conclude with some general observations about multimodality. PMID:22371617

  20. A comparison of noninvasive imaging modalities in the melanoma patient

    SciTech Connect

    Doiron, M.J.; Bernardino, M.E.

    1981-06-01

    The results of radionuclide (RN) liver scans, computed tomography (CT), and ultrasonography (US) were compared in 163 patients. Thirty-eight patients had all three studies, while ten were examined by CT and RN liver scans. One hundred fifteen patients had only US and RN studies. Radionuclide liver scanning demonstrated more false positive and negative studies than CT or US. Also, CT and US demonstrated more areas of metastasis during a single examination than RN liver scans. Ultrasonography displayed roughly the same accuracy of CT when a technically adequate examination was obtained. However, US was hampered by technically inadequate studies in 19% of 153 patients because of interfering intestinal gas. Computed tomography proved the most accurate and reliable modality in 48 patients.

  1. Insights into dendritic cell function using advanced imaging modalities.

    PubMed

    Vyas, Jatin M

    2012-11-15

    The application of advanced imaging techniques to fundamental questions in immunology has provided insight into dendritic cell function and has challenged dogma created using static imaging of lymphoid tissue. The history of dendritic cell biology has a storied past and is tightly linked to imaging. The development of imaging techniques that emphasize live cell imaging in situ has provided not only breath-taking movies, but also novel insights into the importance of spatiotemporal relationships between antigen presenting cells and T cells. This review serves to provide a primer on two-photon microscopy, TIRF microscopy, spinning disk confocal microscopy and optical trapping and provides selective examples of insights gained from these tools on dendritic cell biology.

  2. Carbon-11 radiolabeling of iron-oxide nanoparticles for dual-modality PET/MR imaging

    NASA Astrophysics Data System (ADS)

    Sharma, Ramesh; Xu, Youwen; Kim, Sung Won; Schueller, Michael J.; Alexoff, David; Smith, S. David; Wang, Wei; Schlyer, David

    2013-07-01

    Dual-modality imaging, using Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) simultaneously, is a powerful tool to gain valuable information correlating structure with function in biomedicine. The advantage of this dual approach is that the strengths of one modality can balance the weaknesses of the other. However, success of this technique requires developing imaging probes suitable for both. Here, we report on the development of a nanoparticle labeling procedure via covalent bonding with carbon-11 PET isotope. Carbon-11 in the form of [11C]methyl iodide was used as a methylation agent to react with carboxylic acid (-COOH) and amine (-NH2) functional groups of ligands bound to the nanoparticles (NPs). The surface coating ligands present on superparamagnetic iron-oxide nanoparticles (SPIO NPs) were radiolabeled to achieve dual-modality PET/MR imaging capabilities. The proof-of-concept dual-modality PET/MR imaging using the radiolabeled SPIO NPs was demonstrated in an in vivo experiment.Dual-modality imaging, using Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET) simultaneously, is a powerful tool to gain valuable information correlating structure with function in biomedicine. The advantage of this dual approach is that the strengths of one modality can balance the weaknesses of the other. However, success of this technique requires developing imaging probes suitable for both. Here, we report on the development of a nanoparticle labeling procedure via covalent bonding with carbon-11 PET isotope. Carbon-11 in the form of [11C]methyl iodide was used as a methylation agent to react with carboxylic acid (-COOH) and amine (-NH2) functional groups of ligands bound to the nanoparticles (NPs). The surface coating ligands present on superparamagnetic iron-oxide nanoparticles (SPIO NPs) were radiolabeled to achieve dual-modality PET/MR imaging capabilities. The proof-of-concept dual-modality PET/MR imaging using the radiolabeled

  3. New magnetic resonance imaging modalities for Crohn disease.

    PubMed

    Yacoub, Joseph H; Oto, Aytekin

    2014-02-01

    Magnetic resonance (MR) enterography has an increasing role in the evaluation of the small bowel in patients with Crohn disease. MR enterography is accurate for disease assessment and can influence the choice of therapy. Functional sequences may increase the role of MR enterography in Crohn disease. Techniques such as high-resolution MR enterography, diffusion-weighted imaging, dynamic contrast-enhanced MR imaging, magnetization transfer, and MR motility imaging may allow better assessment of disease extent, activity, and severity. Quantitative analysis using these advanced techniques as well as the standard techniques may provide methods for evaluating and following the disease in the future.

  4. Robotic 3D scanner as an alternative to standard modalities of medical imaging.

    PubMed

    Chromy, Adam; Zalud, Ludek

    2014-01-01

    There are special medical cases, where standard medical imaging modalities are able to offer sufficient results, but not in the optimal way. It means, that desired results are produced with unnecessarily high expenses, with redundant informations or with needless demands on patient. This paper deals with one special case, where information useful for examination is the body surface only, inner sight into the body is needless. New specialized medical imaging device is developed for this situation. In the Introduction section, analysis of presently used medical imaging modalities is presented, which declares, that no available imaging device is best fitting for mentioned purposes. In the next section, development of the new specialized medical imaging device is presented, and its principles and functions are described. Then, the parameters of new device are compared with present ones. It brings significant advantages comparing to present imaging systems.

  5. Imaging Modalities Relevant to Intracranial Pressure Assessment in Astronauts

    NASA Technical Reports Server (NTRS)

    Sargsyan, Ashot E.; Kramer, Larry A.; Hamilton, Douglas R.; Fogarty, Jennifer; Polk, J. D.

    2011-01-01

    Learning Objectives of this slide presentation are: 1: To review the morphological changes in orbit structures caused by elevated Intracranial Pressure (ICP), and their imaging representation. 2: To learn about the similarities and differences between MRI and sonographic imaging of the eye and orbit. 3: To learn about the role of MRI and sonography in the noninvasive assessment of intracranial pressure in aerospace medicine, and the added benefits from their combined interpretation.

  6. Multiphoton microscopy as a diagnostic imaging modality for lung cancer

    NASA Astrophysics Data System (ADS)

    Pavlova, Ina; Hume, Kelly R.; Yazinski, Stephanie A.; Peters, Rachel M.; Weiss, Robert S.; Webb, Watt W.

    2010-02-01

    Lung cancer is the leading killer among all cancers for both men and women in the US, and is associated with one of the lowest 5-year survival rates. Current diagnostic techniques, such as histopathological assessment of tissue obtained by computed tomography guided biopsies, have limited accuracy, especially for small lesions. Early diagnosis of lung cancer can be improved by introducing a real-time, optical guidance method based on the in vivo application of multiphoton microscopy (MPM). In particular, we hypothesize that MPM imaging of living lung tissue based on twophoton excited intrinsic fluorescence and second harmonic generation can provide sufficient morphologic and spectroscopic information to distinguish between normal and diseased lung tissue. Here, we used an experimental approach based on MPM with multichannel fluorescence detection for initial discovery that MPM spectral imaging could differentiate between normal and neoplastic lung in ex vivo samples from a murine model of lung cancer. Current results indicate that MPM imaging can directly distinguish normal and neoplastic lung tissues based on their distinct morphologies and fluorescence emission properties in non-processed lung tissue. Moreover, we found initial indication that MPM imaging differentiates between normal alveolar tissue, inflammatory foci, and lung neoplasms. Our long-term goal is to apply results from ex vivo lung specimens to aid in the development of multiphoton endoscopy for in vivo imaging of lung abnormalities in various animal models, and ultimately for the diagnosis of human lung cancer.

  7. [Optic disc drusen in children: Advantages of various imaging modalities].

    PubMed

    Naoum, S; Bouacha, I; Drumare, I; Marks, C; Defoort-Delemmes, S

    2016-04-01

    In children, optic disc drusen pose a diagnostic problem with papilledema when they are buried. The goal of our study is to retrospectively compare the results of examinations performed in 34 children with optic disc drusen. In children who underwent ultrasonography and autofluorescence imaging, the results were conclusive in both examinations in 44.7% of cases, and in neither of the two examinations in 27.6% of cases. Ultrasonography alone demonstrated superiority in diagnosing 27.6% of eyes, whereas autofluorescence imaging was inconclusive. Since diagnostic confusion with papilledema persisted in seven children, angiography was performed. B-mode ultrasonography constitutes a relevant examination in the diagnosis of buried optic disc drusen in children and shows superiority in our study compared to autofluorescence imaging.

  8. Construction of specific magnetic resonance imaging/optical dual-modality molecular probe used for imaging angiogenesis of gastric cancer.

    PubMed

    Yan, Xuejie; Song, Xiaoyan; Wang, Zhenbo

    2017-05-01

    The purpose of the study was to construct specific magnetic resonance imaging (MRI)/optical dual-modality molecular probe. Tumor-bearing animal models were established. MRI/optical dual-modality molecular probe was construed by coupling polyethylene glycol (PEG)-modified nano-Fe3O4 with specific targeted cyclopeptide GX1 and near-infrared fluorescent dyes Cy5.5. MRI/optical imaging effects of the probe were observed and the feasibility of in vivo double-modality imaging was discussed. It was found that, the double-modality probe was of high stability; tumor signal of the experimental group tended to be weak after injection of the probe, but rose to a level which was close to the previous level after 18 h (p > 0.05). We successively completed the construction of an ideal MRI/optical dual-modality molecular probe. MRI/optical dual-modality molecular probe which can selectively gather in gastric cancer is expected to be a novel probe used for diagnosing gastric cancer in the early stage.

  9. Noninvasive diagnosis of cirrhosis: A review of different imaging modalities

    PubMed Central

    De Robertis, Riccardo; D’Onofrio, Mirko; Demozzi, Emanuele; Crosara, Stefano; Canestrini, Stefano; Pozzi Mucelli, Roberto

    2014-01-01

    Progressive hepatic fibrosis can lead to cirrhosis, so its early detection is fundamental. Staging fibrosis is also critical for prognosis and management. The gold standard for these aims is liver biopsy, but it has several drawbacks, as it is invasive, expensive, has poor acceptance, is prone to inter observer variability and sampling errors, has poor repeatability, and has a risk of complications and mortality. Therefore, non-invasive imaging tests have been developed. This review mainly focuses on the role of transient elastography, acoustic radiation force impulse imaging, and magnetic resonance-based methods for the noninvasive diagnosis of cirrhosis. PMID:24966594

  10. Dual-Modality Prostate Imaging with PET and Transrectal Ultrasound

    DTIC Science & Technology

    2011-09-01

    Emission Tomography–Transrectal Ultrasound (PET-TRUS) imaging of the prostate and validate the technology with phantom and “proof of principle” human...position a prostate near the PET-center, and this method was also used for phantom imaging in Years 2-5. The TRUS probe is rigidly attached to the TRUS...scanner table. This stabilizer arm moves to allow correct positioning of the TRUS probe in a human subject (or phantom ), then its position is fixed by

  11. [Image-guided radiotherapy: rational, modalities and results].

    PubMed

    de Crevoisier, R; Louvel, G; Cazoulat, G; Leseur, J; Lafond, C; Lahbabi, K; Chira, C; Lagrange, J-L

    2009-01-01

    The objective of Image-Guided Radiotherapy (IGRT) is to take in account the inter- or/and intrafraction anatomic variations (organ motion and deformations) in order to improve treatment accuracy. The IGRT should therefore translate in a clinical benefit the recent advances in both tumor definition thanks to functional imaging, and dose distribution thanks to intensity modulated radiotherapy. The IGRT enables direct or indirect tumor visualization during radiation delivery. If the tumor position does not correspond with the theoretical location of target derived from planning system, the table is moved. In case of important uncertainties related to target deformation, a new planning can be discussed. IGRT is realized by different types of devices which can vary in principle and as well as in their implementation: from LINAC-integrated-kV (or MV)-Cone Beam CTs to helicoidal tomotherapy, Cyberknife and Novalis low-energy stereoscopic imaging system. These techniques led to a more rational choice of Planning Target Volume. Being recently introduced in practice, the clinical results of this technique are still limited. Nevertheless, until so far, IGRT has showed promising results with reports of minimal acute toxicity. This review describes IGRT for various tumor localizations. The dose delivered by on board imaging should be taken in account. A strong quality control is required for safety and proper prospective evaluation of the clinical benefit of IGRT.

  12. Comparative effectiveness of imaging modalities to determine metastatic breast cancer treatment response.

    PubMed

    Lee, Christoph I; Gold, Laura S; Nelson, Heidi D; Chou, Roger; Ramsey, Scott D; Sullivan, Sean D

    2015-02-01

    We performed a systematic review to address the comparative effectiveness of different imaging modalities in evaluating treatment response among metastatic breast cancer patients. We searched seven multidisciplinary electronic databases for relevant publications (January 2003-December 2013) and performed dual abstraction of details and results for all clinical studies that involved stage IV breast cancer patients and evaluated imaging for detecting treatment response. Among 159 citations reviewed, 17 single-institution, non-randomized, observational studies met our inclusion criteria. Several studies demonstrate that changes in PET/CT standard uptake values are associated with changes in tumor volume as determined by bone scan, MRI, and/or CT. However, no studies evaluated comparative test performance between modalities or determined relationships between imaging findings and subsequent clinical decisions. Evidence for imaging's effectiveness in determining treatment response among metastatic breast cancer patients is limited. More rigorous research is needed to address imaging's value in this patient population.

  13. Simultaneous dual modality optical and MR imaging of mouse dorsal skin-fold window chamber

    NASA Astrophysics Data System (ADS)

    Salek, Mir Farrokh; Pagel, Mark D.; Gmitro, Arthur F.

    2011-02-01

    Optical imaging and MRI have both been used extensively to study tumor microenvironment. The two imaging modalities are complementary and can be used to cross-validate one another for specific measurements. We have developed a modular platform that is capable of doing optical microscopy inside an MRI instrument. To do this, an optical relay system transfers the image to outside of the MR bore to a commercial grade CCD camera. This enables simultaneous optical and MR imaging of the same tissue and thus creates the ideal situation for comparative or complementary studies using both modalities. Initial experiments have been done using GFP labeled prostate cancer cells implanted in mouse dorsal skin fold window chamber. Vascular hemodynamics and vascular permeability were studied using our imaging system. Towards this goal, we developed a dual MR-Optical contrast agent by labeling BSA with both Gd-DTPA and Alexa Fluor. Overall system design and results of these preliminary vascular studies are presented.

  14. Multi-modal Color Medical Image Fusion Using Quaternion Discrete Fourier Transform

    NASA Astrophysics Data System (ADS)

    Nawaz, Qamar; Xiao, Bin; Hamid, Isma; Jiao, Du

    2016-12-01

    Multimodal image fusion is a process of combining multiple images, generated by identical or diverse imaging modalities, to get precise inside information about the same body organ. In recent years, various multimodal image fusion algorithms have been proposed to fuse medical image. However, most of them focus on fusing grayscale images. This paper proposes a novel algorithm for the fusion of multimodal color medical images. The proposed algorithm divides source images into blocks, converts each RGB block into quaternion representation and transforms them from special domain to frequency domain by applying quaternion discrete Fourier transform. The fused coefficients are obtained by calculating and comparing contrast values of corresponding coefficients in transformed blocks. The resultant fused image is reconstructed by merging all the blocks after applying inverse quaternion discrete Fourier transform on each block. Experimental evaluation demonstrates that the proposed algorithm qualitatively outperforms many existing state-of-the-art multimodal image fusion algorithms.

  15. DEVELOPMENT OF A DUAL MODALITY TOMOGRAPHIC IMAGING SYSTEM FOR BIOLUMINESCENCE AND PET

    SciTech Connect

    CHATZIIOANNOU, ARION

    2011-12-21

    The goal of this proposal was to develop a new hybrid imaging modality capable to simultaneously image optical bioluminescence signals, as well as radionuclide emissions from the annihilation of positrons originating from molecular imaging probes in preclinical mouse models. This new technology enables the simultaneous in-vivo measurements of both emissions that could be produced from a single or a combination of two different biomarkers. It also facilitates establishing the physical limitations of bioluminescence imaging, its tomographic and spectral image reconstruction potential and the quantification of bioluminescence signals.

  16. Telepathology and imaging spectroscopy as a new modality in histopathology.

    PubMed

    Vari, S G; Müller, G; Lerner, J M; Naber, R D

    1999-01-01

    Telemedicine started in the late 1950's by transmitting data on patients' pulse and heart rates. In the 1980's it expanded to radiology and orthopedics. The technology is now expanding to other specialties that can digitally gather patient data. Telepathology comprises the transmission of microscopic images via telecommunication network. Image compression and multiplexing technologies enabled high-resolution telepathology as well as real-time video consultations over international telephone lines. Organ transplantation has become a viable treatment and offers new life to an increasing number of patients suffering from chronic end stage diseases and from irreversible organ failure. Rejection is still a major problem in kidney, liver, and heart transplantation. To gain further insight into the complex interactions within the components of the immune system, it has become increasingly necessary to develop rapid and simple methods to monitor the status of the immune system in patients. Clinical signs suggest organ rejection and abnormal laboratory test results, but only histological signs on biopsy specimens are adequately specific. The financial cost of organ transplant makes it imperative to develop tools for the early identification and treatment of organ rejection. An increasingly sensitive and accurate way of localizing key structures and abnormalities is through spectroscopy of either H&E stained samples or with a fluorescent tag (fluorophore) or by relying on natural fluorescence. The system is based on a unique Prism and Mirror Imaging Spectroscopy System ("PARISS), spectrometer originally designed and implemented for remote Earth monitoring from space and aircraft and astronomical imaging spectroscopy. Compact and lightweight both the mirror and prism are presently constructed in inexpensive glass but can also be injection molded in plastic. Any number of vendors anywhere in the world can produce all parts of the assembly. This greatly enhances the chances of

  17. Fusion Imaging: A Novel Staging Modality in Testis Cancer

    DTIC Science & Technology

    2010-01-01

    conducted. Patients underwent con- ventional imaging evaluation to include CT abdo - men/pelvis, CXR, as well as a full clinical evaluation to include...positron emission tomography (PET) has been utilized in con- junction with computed tomography ( CT ) and chest radiographs (CXR) to survey patients for...metastatic or recurrent disease. While CT is the standard of care for locating the presence of lymphadenopathy or retro- peritoneal masses, its

  18. Urolithoscintigraphy: preliminary report of a new imaging modality for urolithiasis.

    PubMed

    Wolf, J S; Irby, P B; Shields, A; Yuen-Green, M S; Hattner, R S; Stoller, M L

    1994-04-01

    We investigated the use of bisphosphonates, analogs of pyrophosphate that bind to mineralized tissue, to image renal calculi in vivo. Twenty stone-bearing kidneys in 15 patients without urinary obstruction were studied. 99mTechnetium-methylene diphosphonate was injected intravenously followed by 20 mg of furosemide 4 hours later, and images were obtained by gamma counter for 30 minutes. Areas of increased uptake corresponded with the sites of calculi, and even small or radiolucent calculi were easily seen. Counts in the region of each kidney, the L4 vertebral body, and a background area were combined to calculate a scintigram index (SI) for each kidney. The mean SI of the stone-bearing kidneys was 4.8 +/- 3.5 v 1.3 +/- 0.4 for the normal kidneys. There was correlation of the SI with stone composition and size but not with radiographic density. After correction for size, the SI of stone-bearing kidneys remained significantly higher than the SI of normal kidneys, but the differences between calculi of different compositions were diminished. Nonetheless, high SI values were associated with soft types of calculi and low values with hard types. Future investigations will reveal if this association is constant and if there is any relation between bisphosphonate uptake and response to lithotripsy. The sensitivity of urolithoscintigraphy to image small or radiolucent calculi may make it an effective technique for the assessment of residual fragments after lithotripsy.

  19. A prototype hand-held tri-modal instrument for in vivo ultrasound, photoacoustic, and fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Kang, Jeeun; Chang, Jin Ho; Wilson, Brian C.; Veilleux, Israel; Bai, Yanhui; DaCosta, Ralph; Kim, Kang; Ha, Seunghan; Lee, Jong Gun; Kim, Jeong Seok; Lee, Sang-Goo; Kim, Sun Mi; Lee, Hak Jong; Ahn, Young Bok; Han, Seunghee; Yoo, Yangmo; Song, Tai-Kyong

    2015-03-01

    Multi-modality imaging is beneficial for both preclinical and clinical applications as it enables complementary information from each modality to be obtained in a single procedure. In this paper, we report the design, fabrication, and testing of a novel tri-modal in vivo imaging system to exploit molecular/functional information from fluorescence (FL) and photoacoustic (PA) imaging as well as anatomical information from ultrasound (US) imaging. The same ultrasound transducer was used for both US and PA imaging, bringing the pulsed laser light into a compact probe by fiberoptic bundles. The FL subsystem is independent of the acoustic components but the front end that delivers and collects the light is physically integrated into the same probe. The tri-modal imaging system was implemented to provide each modality image in real time as well as co-registration of the images. The performance of the system was evaluated through phantom and in vivo animal experiments. The results demonstrate that combining the modalities does not significantly compromise the performance of each of the separate US, PA, and FL imaging techniques, while enabling multi-modality registration. The potential applications of this novel approach to multi-modality imaging range from preclinical research to clinical diagnosis, especially in detection/localization and surgical guidance of accessible solid tumors.

  20. A prototype hand-held tri-modal instrument for in vivo ultrasound, photoacoustic, and fluorescence imaging.

    PubMed

    Kang, Jeeun; Chang, Jin Ho; Wilson, Brian C; Veilleux, Israel; Bai, Yanhui; DaCosta, Ralph; Kim, Kang; Ha, Seunghan; Lee, Jong Gun; Kim, Jeong Seok; Lee, Sang-Goo; Kim, Sun Mi; Lee, Hak Jong; Ahn, Young Bok; Han, Seunghee; Yoo, Yangmo; Song, Tai-Kyong

    2015-03-01

    Multi-modality imaging is beneficial for both preclinical and clinical applications as it enables complementary information from each modality to be obtained in a single procedure. In this paper, we report the design, fabrication, and testing of a novel tri-modal in vivo imaging system to exploit molecular/functional information from fluorescence (FL) and photoacoustic (PA) imaging as well as anatomical information from ultrasound (US) imaging. The same ultrasound transducer was used for both US and PA imaging, bringing the pulsed laser light into a compact probe by fiberoptic bundles. The FL subsystem is independent of the acoustic components but the front end that delivers and collects the light is physically integrated into the same probe. The tri-modal imaging system was implemented to provide each modality image in real time as well as co-registration of the images. The performance of the system was evaluated through phantom and in vivo animal experiments. The results demonstrate that combining the modalities does not significantly compromise the performance of each of the separate US, PA, and FL imaging techniques, while enabling multi-modality registration. The potential applications of this novel approach to multi-modality imaging range from preclinical research to clinical diagnosis, especially in detection/localization and surgical guidance of accessible solid tumors.

  1. Comparison of multispectral wide-field optical imaging modalities to maximize image contrast for objective discrimination of oral neoplasia

    NASA Astrophysics Data System (ADS)

    Roblyer, Darren; Kurachi, Cristina; Stepanek, Vanda; Schwarz, Richard A.; Williams, Michelle D.; El-Naggar, Adel K.; Lee, J. Jack; Gillenwater, Ann M.; Richards-Kortum, Rebecca

    2010-11-01

    Multispectral widefield optical imaging has the potential to improve early detection of oral cancer. The appropriate selection of illumination and collection conditions is required to maximize diagnostic ability. The goals of this study were to (i) evaluate image contrast between oral cancer/precancer and non-neoplastic mucosa for a variety of imaging modalities and illumination/collection conditions, and (ii) use classification algorithms to evaluate and compare the diagnostic utility of these modalities to discriminate cancers and precancers from normal tissue. Narrowband reflectance, autofluorescence, and polarized reflectance images were obtained from 61 patients and 11 normal volunteers. Image contrast was compared to identify modalities and conditions yielding greatest contrast. Image features were extracted and used to train and evaluate classification algorithms to discriminate tissue as non-neoplastic, dysplastic, or cancer; results were compared to histologic diagnosis. Autofluorescence imaging at 405-nm excitation provided the greatest image contrast, and the ratio of red-to-green fluorescence intensity computed from these images provided the best classification of dysplasia/cancer versus non-neoplastic tissue. A sensitivity of 100% and a specificity of 85% were achieved in the validation set. Multispectral widefield images can accurately distinguish neoplastic and non-neoplastic tissue; however, the ability to separate precancerous lesions from cancers with this technique was limited.

  2. Does Breast Magnetic Resonance Imaging Combined With Conventional Imaging Modalities Decrease the Rates of Surgical Margin Involvement and Reoperation?

    PubMed Central

    Lai, Hung-Wen; Chen, Chih-Jung; Lin, Ying-Jen; Chen, Shu-Ling; Wu, Hwa-Koon; Wu, Yu-Ting; Kuo, Shou-Jen; Chen, Shou-Tung; Chen, Dar-Ren

    2016-01-01

    Abstract The objective of this study was to assess whether preoperative breast magnetic resonance imaging (MRI) combined with conventional breast imaging techniques decreases the rates of margin involvement and reexcision. Data on patients who underwent surgery for primary operable breast cancer were obtained from the Changhua Christian Hospital (CCH) breast cancer database. The rate of surgical margin involvement and the rate of reoperation were compared between patients who underwent conventional breast imaging modalities (Group A: mammography and sonography) and those who received breast MRI in addition to conventional imaging (Group B: mammography, sonography, and MRI). A total of 1468 patients were enrolled in this study. Among the 733 patients in Group A, 377 (51.4%) received breast-conserving surgery (BCS) and 356 (48.6%) received mastectomy. Among the 735 patients in Group B, 348 (47.3%) received BCS and 387 (52.7%) received mastectomy. There were no significant differences in operative method between patients who received conventional imaging alone and those that received MRI and conventional imaging (P = 0.13). The rate of detection of pathological multifocal/multicentric breast cancer was markedly higher in patients who received preoperative MRI than in those who underwent conventional imaging alone (14.3% vs 8.6%, P < 0.01). The overall rate of surgical margin involvement was significantly lower in patients who received MRI (5.0%) than in those who received conventional imaging alone (9.0%) (P < 0.01). However, a significant reduction in rate of surgical margin positivity was only observed in patients who received BCS (Group A, 14.6%; Group B, 6.6%, P < 0.01). The overall BCS reoperation rates were 11.7% in the conventional imaging group and 3.2% in the combined MRI group (P < 0.01). There were no significant differences in rate of residual cancer in specimens obtained during reoperation between the 2 preoperative imaging groups

  3. Application of different imaging modalities for diagnosis of Diabetic Macular Edema: A review.

    PubMed

    Mookiah, Muthu Rama Krishnan; Acharya, U Rajendra; Fujita, Hamido; Tan, Jen Hong; Chua, Chua Kuang; Bhandary, Sulatha V; Laude, Augustinus; Tong, Louis

    2015-11-01

    Diabetic Macular Edema (DME) is caused by accumulation of extracellular fluid from hyperpermeable capillaries within the macula. DME is one of the leading causes of blindness among Diabetes Mellitus (DM) patients. Early detection followed by laser photocoagulation can save the visual loss. This review discusses various imaging modalities viz. biomicroscopy, Fluorescein Angiography (FA), Optical Coherence Tomography (OCT) and colour fundus photographs used for diagnosis of DME. Various automated DME grading systems using retinal fundus images, associated retinal image processing techniques for fovea, exudate detection and segmentation are presented. We have also compared various imaging modalities and automated screening methods used for DME grading. The reviewed literature indicates that FA and OCT identify DME related changes accurately. FA is an invasive method, which uses fluorescein dye, and OCT is an expensive imaging method compared to fundus photographs. Moreover, using fundus images DME can be identified and automated. DME grading algorithms can be implemented for telescreening. Hence, fundus imaging based DME grading is more suitable and affordable method compared to biomicroscopy, FA, and OCT modalities.

  4. Multi-modality endoscopic imaging for the detection of colorectal cancer

    NASA Astrophysics Data System (ADS)

    Wall, Richard Andrew

    Optical coherence tomography (OCT) is an imaging method that is considered the optical analog to ultrasound, using the technique of optical interferometry to construct two-dimensional depth-resolved images of tissue microstructure. With a resolution on the order of 10 um and a penetration depth of 1-2 mm in highly scattering tissue, fiber optics-coupled OCT is an ideal modality for the inspection of the mouse colon with its miniaturization capabilities. In the present study, the complementary modalities laser-induced fluorescence (LIF), which offers information on the biochemical makeup of the tissue, and surface magnifying chromoendoscopy, which offers high contrast surface visualization, are combined with OCT in endoscopic imaging systems for the greater specificity and sensitivity in the differentiation between normal and neoplastic tissue, and for the visualization of biomarkers which are indicative of early events in colorectal carcinogenesis. Oblique incidence reflectometry (OIR) also offers advantages, allowing the calculation of bulk tissue optical properties for use as a diagnostic tool. The study was broken up into three specific sections. First, a dual-modality OCTLIF imaging system was designed, capable of focusing light over 325-1300 nm using a reflective distal optics design. A dual-modality fluorescence-based SMC-OCT system was then designed and constructed, capable of resolving the stained mucosal crypt structure of the in vivo mouse colon. The SMC-OCT instrument's OIR capabilities were then modeled, as a modified version of the probe was used measure tissue scattering and absorption coefficients.

  5. Percutaneous ultrasonography as imaging modality and sampling guide for pulmonologists.

    PubMed

    Stigt, Jos A; Groen, Harry J M

    2014-01-01

    Ultrasound (US) imaging is gradually progressing into common practice in contemporary pulmonology. Its main applications are to determine the presence and amount of pleural effusions and to guide subsequent treatment interventions. Guidelines recommend the use of US for these indications. Training programs are organized and competency levels are formulated. Image guidance with US to obtain specimens for pathologic and/or microbiological analysis is less extensively practiced by pulmonologists but it is an important tool for tumour staging and diagnosing diseases. Lung tumours in contact with the pleural surface, pleural thickenings, mediastinal tumours and chest wall tumours are conceivable indications for pulmonologists to approach with the help of US visualization. Moreover, sampling of chest disease-related extrathoracal lesions may also be regarded as the working field of the pulmonologist. For example, supraclavicular and axillar lymph node metastasis, and also soft tissue and bone metastases, are lesions encountered during dissemination tests. US-guided biopsy provides not only a diagnosis, but also gives information on the stage of disease in sometimes inaccessible primary lesions. US-guided sampling increases diagnostic efficacy and safety and enables very precise performance of fine-needle aspirations as well as tissue core biopsies.

  6. Imaging modalities to assess structural birth defects in mutant mouse models.

    PubMed

    Tobita, Kimimasa; Liu, Xiaoqin; Lo, Cecilia W

    2010-09-01

    Assessment of structural birth defects (SBDs) in animal models usually entails conducting detailed necropsy for anatomical defects followed by histological analysis for tissue defects. Recent advances in new imaging technologies have provided the means for rapid phenotyping of SBDs, such as using ultra-high frequency ultrasound biomicroscopy, optical coherence tomography, micro-CT, and micro-MRI. These imaging modalities allow the detailed assessment of organ/tissue structure, and with ultrasound biomicroscopy, structure and function of the cardiovascular system also can be assessed noninvasively, allowing the longitudinal tracking of the fetus in utero. In this review, we briefly discuss the application of these state-of-the-art imaging technologies for phenotyping of SBDs in rodent embryos and fetuses, showing how these imaging modalities may be used for the detection of a wide variety of SBDs.

  7. A highly sensitive x-ray imaging modality for hepatocellular carcinoma detection in vitro.

    PubMed

    Rand, Danielle; Walsh, Edward G; Derdak, Zoltan; Wands, Jack R; Rose-Petruck, Christoph

    2015-01-21

    Innovations that improve sensitivity and reduce cost are of paramount importance in diagnostic imaging. The novel x-ray imaging modality called spatial frequency heterodyne imaging (SFHI) is based on a linear arrangement of x-ray source, tissue, and x-ray detector, much like that of a conventional x-ray imaging apparatus. However, SFHI rests on a complete paradigm reversal compared to conventional x-ray absorption-based radiology: while scattered x-rays are carefully rejected in absorption-based x-ray radiology to enhance the image contrast, SFHI forms images exclusively from x-rays scattered by the tissue. In this study we use numerical processing to produce x-ray scatter images of hepatocellular carcinoma labeled with a nanoparticle contrast agent. We subsequently compare the sensitivity of SFHI in this application to that of both conventional x-ray imaging and magnetic resonance imaging (MRI). Although SFHI is still in the early stages of its development, our results show that the sensitivity of SFHI is an order of magnitude greater than that of absorption-based x-ray imaging and approximately equal to that of MRI. As x-ray imaging modalities typically have lower installation and service costs compared to MRI, SFHI could become a cost effective alternative to MRI, particularly in areas of the world with inadequate availability of MRI facilities.

  8. Alternative Cardiac Imaging Modalities to Echocardiography for the Diagnosis of Infective Endocarditis.

    PubMed

    Wong, Davie; Rubinshtein, Ronen; Keynan, Yoav

    2016-11-01

    Infective endocarditis (IE) is a life-threatening disease. Considered the gold standard for the diagnosis of IE, the modified Duke criteria rely on echocardiographic findings to satisfy its major criterion. Echocardiography is an invaluable tool in the evaluation of patients with suspected IE but suffers from certain limitations. For example, it cannot differentiate vegetation from clot, or between infected and noninfected vegetation, and may miss vegetation and periannular extensions in the presence of prosthetic material. Therefore, alternative cardiac imaging modalities are needed. Nuclear imaging, particularly (18)F-fluorodesoxyglucose positron emission tomography-computed tomography (CT), is becoming increasingly popular in the evaluation of patients for IE and has shown promise in diagnosing valvular and device-related IE when echocardiography results were inconclusive. Other techniques such as radiolabeled leukocyte scintigraphy and single-photon emission computed tomography with or without CT are less well studied, however. Cardiac CT angiography is also evolving as a powerful supplementary tool to echocardiography for the detection of perivalvular complications of IE and for preoperative evaluation of coronary anatomy. The combination of cardiac CT angiography and echocardiography is superior to either test alone in the diagnosis of IE and its complications. Although brain magnetic resonance imaging may impact prognosis and clinical management by identifying cerebral emboli in patients with IE, the role of cardiac and abdominal magnetic resonance imaging is less clear. In conclusion, with these additional diagnostic tools at our disposal, the diagnosis of IE may be achieved in a more timely and accurate manner to secure better clinical outcomes.

  9. Microbubbles loaded with nanoparticles: a route to multiple imaging modalities.

    PubMed

    Park, Jai Il; Jagadeesan, Dinesh; Williams, Ross; Oakden, Wendy; Chung, Siyon; Stanisz, Greg J; Kumacheva, Eugenia

    2010-11-23

    We report a single-step approach to producing small and stable bubbles functionalized with nanoparticles. The strategy includes the following events occurring in sequence: (i) a microfluidic generation of bubbles from a mixture of CO(2) and a minute amount of gases with low solubility in water, in an aqueous solution of a protein, a polysaccharide, and anionic nanoparticles; (ii) rapid dissolution of CO(2) leading to the shrinkage of bubbles and an increase in acidity of the medium in the vicinity of the bubbles; and (iii) co-deposition of the biopolymers and nanoparticles at the bubble-liquid interface. The proposed approach yielded microbubbles with a narrow size distribution, long-term stability, and multiple functions originating from the attachment of metal oxide, metal, or semiconductor nanoparticles onto the bubble surface. We show the potential applications of these bubbles in ultrasound and magnetic resonance imaging.

  10. Eigenanatomy: Sparse Dimensionality Reduction for Multi-Modal Medical Image Analysis

    PubMed Central

    Kandel, Benjamin M.; Wang, Danny JJ; Gee, James C.; Avants, Brian B.

    2014-01-01

    Rigorous statistical analysis of multimodal imaging datasets is challenging. Mass-univariate methods for extracting correlations between image voxels and outcome measurements are not ideal for multimodal datasets, as they do not account for interactions between the different modalities. The extremely high dimensionality of medical images necessitates dimensionality reduction, such as principal component analysis (PCA) or independent component analysis (ICA). These dimensionality reduction techniques, however, consist of contributions from every region in the brain and are therefore difficult to interpret. Recent advances in sparse dimensionality reduction have enabled construction of a set of image regions that explain the variance of the images while still maintaining anatomical interpretability. The projections of the original data on the sparse eigenvectors, however, are highly collinear and therefore difficult to incorporate into mult-modal image analysis pipelines. We propose here a method for clustering sparse eigenvectors and selecting a subset of the eigenvectors to make interpretable predictions from a multi-modal dataset. Evaluation on a publicly available dataset shows that the proposed method outperforms PCA and ICA-based regressions while still maintaining anatomical meaning. To facilitate reproducibility, the complete dataset used and all source code is publicly available. PMID:25448483

  11. Eigenanatomy: sparse dimensionality reduction for multi-modal medical image analysis.

    PubMed

    Kandel, Benjamin M; Wang, Danny J J; Gee, James C; Avants, Brian B

    2015-02-01

    Rigorous statistical analysis of multimodal imaging datasets is challenging. Mass-univariate methods for extracting correlations between image voxels and outcome measurements are not ideal for multimodal datasets, as they do not account for interactions between the different modalities. The extremely high dimensionality of medical images necessitates dimensionality reduction, such as principal component analysis (PCA) or independent component analysis (ICA). These dimensionality reduction techniques, however, consist of contributions from every region in the brain and are therefore difficult to interpret. Recent advances in sparse dimensionality reduction have enabled construction of a set of image regions that explain the variance of the images while still maintaining anatomical interpretability. The projections of the original data on the sparse eigenvectors, however, are highly collinear and therefore difficult to incorporate into multi-modal image analysis pipelines. We propose here a method for clustering sparse eigenvectors and selecting a subset of the eigenvectors to make interpretable predictions from a multi-modal dataset. Evaluation on a publicly available dataset shows that the proposed method outperforms PCA and ICA-based regressions while still maintaining anatomical meaning. To facilitate reproducibility, the complete dataset used and all source code is publicly available.

  12. Surface-Enhanced Raman Spectroscopy: A New Modality for Cancer Imaging

    PubMed Central

    Andreou, Chrysafis; Kishore, Sirish A.; Kircher, Moritz F.

    2015-01-01

    While surface-enhanced Raman scattering (SERS) spectroscopy has traditionally been employed as an in vitro analytical tool, in the past few years the first reports of the feasibility of in vivo imaging of cancer with biocompatible SERS probes have emerged. SERS imaging has great potential in the field of medical imaging because it offers several major theoretical advantages over other molecular imaging methods. Medical imaging using SERS nanoprobes can yield higher sensitivity and higher signal specificity than other imaging modalities while also offering multiplexing capabilities that allow for unique applications. This review article explains the principles of SERS and highlights recent advances for in vivo cancer imaging. In order to present the abilities of the method as accurate as possible, the discussion is limited to studies in which the imaging data were confirmed by histological correlation. PMID:26182971

  13. Transperineal ultrasonography in perianal Crohn disease: A valuable imaging modality.

    PubMed

    Wright, Emily K; Novak, Kerri L; Lu, Cathy; Panaccione, Remo; Ghosh, Subrata; Wilson, Stephanie R

    2015-01-01

    Aims of treatment for Crohn disease have moved beyond the resolution of clinical symptoms to objective end points including endoscopic and radiological normality. Regular re-evaluation of disease status to safely, readily and reliably detect the presence of inflammation and complications is paramount. Improvements in sonographic technology over recent years have facilitated a growing enthusiasm among radiologists and gastroenterologists in the use of ultrasound for the assessment of inflammatory bowel disease. Transabdominal intestinal ultrasound is accurate, affordable and safe for the assessment of luminal inflammation and complications in Crohn disease, and can be performed with or without the use of intravenous contrast enhancement. Perianal fistulizing disease is a common, complex and often treatment-refractory complication of Crohn disease, which requires regular radiological monitoring. Endoanal ultrasound is invasive, uncomfortable and yields limited assessment of the perineal region. Although magnetic resonance imaging of the pelvis is established, timely access may be a problem. Transperineal ultrasound has been described in small studies, and is an accurate, painless and cost-effective method for documenting perianal fluid collections, fistulas and sinus tracts. In the present article, the authors review the literature regarding perineal ultrasound for the assessment of perianal Crohn disease and use case examples to illustrate its clinical utility.

  14. Multi-Modal Optical Imaging of the Cerebellum in Animals.

    PubMed

    Allegra Mascaro, Anna Letizia; Sacconi, Leonardo; Silvestri, Ludovico; Knott, Graham; Pavone, Francesco S

    2015-10-17

    Thanks to their flexibility, optical techniques could be the key to explore anatomy, plasticity, and functionality of the cerebellum. As an example, an in vivo analysis of the dynamic remodeling of cerebellar axons by nonlinear microscopy can provide fundamental insights of the mechanism that promotes neuronal regeneration. Several studies showed that damaged climbing fibers are capable of regrowing also in adult animals. The investigation of the time-lapse dynamics of degeneration and regeneration of these axons within their complex environment can be performed by time-lapse two-photon fluorescence (TPF) imaging in vivo. Here, we show that single axonal branches can be dissected by laser axotomy, thus avoiding collateral damage to the adjacent dendrite and the formation of a persistent glial scar. Despite the very small denervated area, the injured axons consistently reshaped the connectivity with surrounding neurons and sprouted new branches through the intact surroundings. Correlative light and electron microscopy revealed that the sprouted branch contains large numbers of vesicles, with varicosities in the close vicinity of Purkinje dendrites. By using an RNA interference approach, we found that downregulating GAP-43 causes a significant increase in the turnover of presynaptic boutons and hampers the generation of reactive sprouts. Further, we report how nonlinear microscopy in combination with novel voltage sensitive dyes or transgenic mice allow optical registrations of action potential across a population of neurons opening promising prospective in understanding brain functionality. Finally, we describe novel implementations of light-sheet microscopy to resolve neuronal anatomy in whole cerebellum with cellular resolution. The understanding gained from these complementary optical methods may provide a deeper comprehension of the cerebellum.

  15. A graph-based approach for the retrieval of multi-modality medical images.

    PubMed

    Kumar, Ashnil; Kim, Jinman; Wen, Lingfeng; Fulham, Michael; Feng, Dagan

    2014-02-01

    In this paper, we address the retrieval of multi-modality medical volumes, which consist of two different imaging modalities, acquired sequentially, from the same scanner. One such example, positron emission tomography and computed tomography (PET-CT), provides physicians with complementary functional and anatomical features as well as spatial relationships and has led to improved cancer diagnosis, localisation, and staging. The challenge of multi-modality volume retrieval for cancer patients lies in representing the complementary geometric and topologic attributes between tumours and organs. These attributes and relationships, which are used for tumour staging and classification, can be formulated as a graph. It has been demonstrated that graph-based methods have high accuracy for retrieval by spatial similarity. However, naïvely representing all relationships on a complete graph obscures the structure of the tumour-anatomy relationships. We propose a new graph structure derived from complete graphs that structurally constrains the edges connected to tumour vertices based upon the spatial proximity of tumours and organs. This enables retrieval on the basis of tumour localisation. We also present a similarity matching algorithm that accounts for different feature sets for graph elements from different imaging modalities. Our method emphasises the relationships between a tumour and related organs, while still modelling patient-specific anatomical variations. Constraining tumours to related anatomical structures improves the discrimination potential of graphs, making it easier to retrieve similar images based on tumour location. We evaluated our retrieval methodology on a dataset of clinical PET-CT volumes. Our results showed that our method enabled the retrieval of multi-modality images using spatial features. Our graph-based retrieval algorithm achieved a higher precision than several other retrieval techniques: gray-level histograms as well as state

  16. Continuous monitoring of arthritis in animal models using optical imaging modalities

    NASA Astrophysics Data System (ADS)

    Son, Taeyoon; Yoon, Hyung-Ju; Lee, Saseong; Jang, Won Seuk; Jung, Byungjo; Kim, Wan-Uk

    2014-10-01

    Given the several difficulties associated with histology, including difficulty in continuous monitoring, this study aimed to investigate the feasibility of optical imaging modalities-cross-polarization color (CPC) imaging, erythema index (EI) imaging, and laser speckle contrast (LSC) imaging-for continuous evaluation and monitoring of arthritis in animal models. C57BL/6 mice, used for the evaluation of arthritis, were divided into three groups: arthritic mice group (AMG), positive control mice group (PCMG), and negative control mice group (NCMG). Complete Freund's adjuvant, mineral oil, and saline were injected into the footpad for AMG, PCMG, and NCMG, respectively. LSC and CPC images were acquired from 0 through 144 h after injection for all groups. EI images were calculated from CPC images. Variations in feet area, EI, and speckle index for each mice group over time were calculated for quantitative evaluation of arthritis. Histological examinations were performed, and the results were found to be consistent with those from optical imaging analysis. Thus, optical imaging modalities may be successfully applied for continuous evaluation and monitoring of arthritis in animal models.

  17. Dual-modal (OIS/LSCI) imager of cerebral cortex in freely moving animals

    NASA Astrophysics Data System (ADS)

    Lu, Hongyang; Miao, Peng; Liu, Qi; Li, Yao; Tong, Shanbao

    2012-03-01

    Optical intrinsic signals (OIS) and laser speckle contrast imaging (LSCI) have been used for years in the study of the cerebral blood flow (CBF) and hemodynamic responses to the neural activity under functional stimulation. So far, most in vivo rodent experiments are based on the anesthesia model when the animals are in unconscious and restrained conditions. The influences of anesthesia on the neural activity have been documented in literature. In this study, we designed a miniature head-mounted dual-modal imager in freely moving animals that could monitor in real time the coupling of local oxygen consumption and blood perfusion of CBF by integrating different imaging modalities of OIS and LSCI. The system facilitates the study the cortical hemodynamics and neural-hemodynamic coupling in real time in freely moving animals.

  18. Photoacoustic imaging and surface-enhanced Raman spectroscopy using dual modal contrast agents

    NASA Astrophysics Data System (ADS)

    Park, Sungjo; Lee, Seunghyun; Cha, Myeonggeun; Jeong, Cheolhwan; Kang, Homan; Park, So Yeon; Lee, Yoon-sik; Jeong, Daehong; Kim, Chulhong

    2016-03-01

    Recently, photoacoustic tomography (PAT) has emerged as a remarkable non-invasive imaging modality that provides a strong optical absorption contrast, high ultrasonic resolution, and great penetration depth. Thus, PAT has been widely used as an in vivo preclinical imaging tool. Surface-enhanced Raman spectroscopy (SERS) is another attractive sensing technology in biological research because it offers highly sensitive chemical analyses and multiplexed detection. By performing dual-modal imaging of SERS and PAT, high-resolution structural PAT imaging and high-sensitivity SERS sensing can be achieved. At the same time, it is equally important to develop a dual modal contrast agent for this purpose. To perform both PAT and SERS, we synthesized PEGylated silver bumpy nanoshells (AgBSs). The AgBSs generate strong PA signals owing to their strong optical absorption properties as well as sensitive SERS signals because of the surface plasmon resonance effect. Then, multiplexed Raman chemicals were synthesized to enhance the sensitivity of Raman. We have photoacoustically imaged the sentinel lymph nodes of small animals after intradermal injection of multiplexed agents. Furthermore, the chemical composition of each agent has been distinguished through SERS.

  19. General comparison of functional imaging in nuclear medicine with other modalities

    SciTech Connect

    Adam, W.E.

    1987-01-01

    New (noninvasive) diagnostic procedures in medicine (ultrasound (US), digital subtraction angiography (DSA), computed tomography (CT), nuclear magnetic resonance (NMR)) create a need for a review of the clinical utility of functional imaging in nuclear medicine. A general approach that is valid for all imaging procedures is not possible. For this reason, an individual assessment for each class of functional imaging is necessary, taking into account the complexity and sophistication of the various imaging procedures. This leads to a hierarchical order: first order functional imaging: imaging of organ motion (heart, lungs, blood); second order functional imaging: imaging of excretory function (kidneys, liver); and third and fourth order functional imaging: imaging of metabolism (except excretory function). First order functional imaging is possible fundamentally, although with limitations in detail, by all modalities. Second order functional imaging is not possible with US. Third and fourth order functional imaging is a privilege of nuclear medicine alone. Up to now, NMR has not proven clinically useful to produce metabolic images in its true sense. First and second order functional imaging of nonradioactive procedures face severe disadvantages, including difficulties in performing stress investigations, which are essential for coronary heart disease, limited capability for true quantitative information (eg, kidney clearance in mL/min), side effects of contrast media and paramagnetic substances, and high costs. 58 references.

  20. Imaging modalities in hand osteoarthritis - status and perspectives of conventional radiography, magnetic resonance imaging, and ultrasonography

    PubMed Central

    2011-01-01

    Hand osteoarthritis (OA) is very frequent in middle-aged and older women and men in the general population. Currently, owing to high feasibility and low costs, conventional radiography (CR) is the method of choice for evaluation of hand OA. CR provides a two-dimensional picture of bony changes, such as osteophytes, erosions, cysts, and sclerosis, and joint space narrowing as an indirect measure of cartilage loss. There are several standardized scoring methods for evaluation of radiographic hand OA. The scales have shown similar reliability, validity, and sensitivity to change, and no conclusion about the preferred instrument has been drawn. Patients with hand OA may experience pain, stiffness, and physical disability, but the associations between radiographic findings and clinical symptoms are weak to moderate and vary across studies. OA is, indeed, recognized to involve the whole joint, and modern imaging techniques such as ultrasound (US) and magnetic resonance imaging (MRI) could be valuable tools for better evaluation of hand OA. Standardized scoring methods have been proposed for both modalities. Several studies have examined the validity of US features in hand OA, whereas knowledge of the validity of MRI is more limited. However, both synovitis (detected by either US or MRI) and MRI-defined bone marrow lesions have been associated with pain, indicating that treatment of inflammation is important for pain management in hand OA. Both US and MRI have shown better sensitivity than CR in detection of erosions, and this may indicate that erosive hand OA may be more common than previously thought. PMID:22189142

  1. Coupling CARS with multiphoton fluorescence and high harmonic generation imaging modalities using a femtosecond laser source

    NASA Astrophysics Data System (ADS)

    Chen, Hongtao; Slipchenko, Mikhail N.; Zhu, Jiabin; Buhman, Kimberly K.; Cheng, Ji-Xin

    2009-02-01

    Multimodal nonlinear optical imaging has opened new opportunities and becomes a powerful tool for imaging complex tissue samples with inherent 3D spatial resolution.. We present a robust and easy-to-operate approach to add the coherent anti-stokes Raman scattering (CARS) imaging modality to a widely used multiphoton microscope. The laser source composed of a Mai Tai femtosecond laser and an optical parametric oscillator (OPO) offers one-beam, two-beam and three-beam modalities. The Mai Tai output at 790 nm is split into two beams, with 80% of the power being used to pump the OPO. The idler output at 2036 nm from OPO is doubled using a periodically poled lithium niobate (PPLN) crystal. This frequency-doubled idler beam at 1018 nm is sent through a delay line and collinearly combined with the other Mai Tai beam for CARS imaging on a laser-scanning microscope. This Mai Tai beam is also used for multiphoton fluorescence and second harmonic generation (SHG) imaging. The signal output at 1290 nm from OPO is used for SHG and third-harmonic generation (THG) imaging. External detectors are installed for both forward and backward detection, whereas two internal lamda-scan detectors are employed for microspectroscopy analysis. This new system allows vibrationally resonant CARS imaging of lipid bodies, SHG imaging of collagen fibers, and multiphoton fluorescence analysis in fresh tissues. As a preliminary application, the effect of diacylglycerol acyltransferase 1 (DGAT1) deficiency on liver lipid metabolism in mice was investigated.

  2. Preclinical anatomical, molecular, and functional imaging of the lung with multiple modalities.

    PubMed

    Gammon, Seth T; Foje, Nathan; Brewer, Elizabeth M; Owers, Elizabeth; Downs, Charles A; Budde, Matthew D; Leevy, W Matthew; Helms, My N

    2014-05-15

    In vivo imaging is an important tool for preclinical studies of lung function and disease. The widespread availability of multimodal animal imaging systems and the rapid rate of diagnostic contrast agent development have empowered researchers to noninvasively study lung function and pulmonary disorders. Investigators can identify, track, and quantify biological processes over time. In this review, we highlight the fundamental principles of bioluminescence, fluorescence, planar X-ray, X-ray computed tomography, magnetic resonance imaging, and nuclear imaging modalities (such as positron emission tomography and single photon emission computed tomography) that have been successfully employed for the study of lung function and pulmonary disorders in a preclinical setting. The major principles, benefits, and applications of each imaging modality and technology are reviewed. Limitations and the future prospective of multimodal imaging in pulmonary physiology are also discussed. In vivo imaging bridges molecular biological studies, drug design and discovery, and the imaging field with modern medical practice, and, as such, will continue to be a mainstay in biomedical research.

  3. Photoacoustic and ultrasound dual-modality imaging of human peripheral joints

    NASA Astrophysics Data System (ADS)

    Xu, Guan; Rajian, Justin R.; Girish, Gandikota; Kaplan, Mariana J.; Fowlkes, J. Brian; Carson, Paul L.; Wang, Xueding

    2013-01-01

    A photoacoustic (PA) and ultrasound (US) dual modality system, for imaging human peripheral joints, is introduced. The system utilizes a commercial US unit for both US control imaging and PA signal acquisition. Preliminary in vivo evaluation of the system, on normal volunteers, revealed that this system can recover both the structural and functional information of intra- and extra-articular tissues. Confirmed by the control US images, the system, on the PA mode, can differentiate tendon from surrounding soft tissue based on the endogenous optical contrast. Presenting both morphological and pathological information in joint, this system holds promise for diagnosis and characterization of inflammatory joint diseases such as rheumatoid arthritis.

  4. Rare-Earth Doped Particles as Dual-Modality Contrast Agent for Minimally-Invasive Luminescence and Dual-Wavelength Photoacoustic Imaging

    NASA Astrophysics Data System (ADS)

    Sheng, Yang; Liao, Lun-De; Thakor, Nitish; Tan, Mei Chee

    2014-10-01

    Multi-modal imaging is an emerging area that integrates multiple imaging modalities to simultaneously capture visual information over many spatial scales. Complementary contrast agents need to be co-developed in order to achieve high resolution and contrast. In this work, we demonstrated that rare-earth doped particles (REDPs) can be employed as dual-modal imaging agents for both luminescence and photoacoustic (PA) imaging to achieve intrinsic high contrast, temporal and spatial resolution, reaching deeper depth. REDPs synthesized with different surfactants (citric acid, polyacrylic acid, ethylenediaminetetraacetic acid and sodium citrate) exhibit tunable emission properties and PA signal amplitudes. Amongst these samples, sodium citrate-modified REDPs showed the strongest PA signals. Furthermore, since REDPs have multiple absorption peaks, they offer a unique opportunity for multi-wavelength PA imaging (e.g. PA signals were measured using 520 and 975 nm excitations). The in vivo PA images around the cortical superior sagittal sinus (SSS) blood vessel captured with enhanced signal arising from REDPs demonstrated that in addition to be excellent luminescent probes, REDPs can also be used as successful PA contrast agents. Anisotropic polyacrylic acid-modified REDPs were found to be the best candidates for dual-modal luminescence and PA imaging due to their strong luminescence and PA signal intensities.

  5. Rare-Earth doped particles as dual-modality contrast agent for minimally-invasive luminescence and dual-wavelength photoacoustic imaging.

    PubMed

    Sheng, Yang; Liao, Lun-De; Thakor, Nitish; Tan, Mei Chee

    2014-10-09

    Multi-modal imaging is an emerging area that integrates multiple imaging modalities to simultaneously capture visual information over many spatial scales. Complementary contrast agents need to be co-developed in order to achieve high resolution and contrast. In this work, we demonstrated that rare-earth doped particles (REDPs) can be employed as dual-modal imaging agents for both luminescence and photoacoustic (PA) imaging to achieve intrinsic high contrast, temporal and spatial resolution, reaching deeper depth. REDPs synthesized with different surfactants (citric acid, polyacrylic acid, ethylenediaminetetraacetic acid and sodium citrate) exhibit tunable emission properties and PA signal amplitudes. Amongst these samples, sodium citrate-modified REDPs showed the strongest PA signals. Furthermore, since REDPs have multiple absorption peaks, they offer a unique opportunity for multi-wavelength PA imaging (e.g. PA signals were measured using 520 and 975 nm excitations). The in vivo PA images around the cortical superior sagittal sinus (SSS) blood vessel captured with enhanced signal arising from REDPs demonstrated that in addition to be excellent luminescent probes, REDPs can also be used as successful PA contrast agents. Anisotropic polyacrylic acid-modified REDPs were found to be the best candidates for dual-modal luminescence and PA imaging due to their strong luminescence and PA signal intensities.

  6. Restaging locally advanced rectal cancer by different imaging modalities after preoperative chemoradiation: a comparative study

    PubMed Central

    2013-01-01

    Background To compare the accuracy of different imaging modalities, alone and in combination in predicting findings at surgery after preoperative chemoradiation for locally advanced rectal cancer. Methods Following chemoradiation, tumors were reclassified on the basis of findings on pelvic computed tomography (CT) (94 patients), endorectal ultrasonography (EUS) (138 patients) alone or by both CT and EUS (80 patients). The ability of the imaging modalities, to predict the pathologic T status, N status, and TNM stage at surgery was evaluated and compared. Results Mean age of the patients was 64.5 years (range 28–88 years); 55% were male. CT and EUS combined had a positive predictive value of 20% for pathologic pT1 stage, 29% for pT1, 29% for pT2, and 58% for pT3. Predictive values for the operative TNM stage were 50% for stage I, 45% for stage II, and 31% for stage III. These values did not exceed those for each modality alone. Conclusion The performance of preoperative CT and EUS in predicting the T and TNM stage of rectal cancer at surgery is poor. Neither modality alone nor the two combined is sufficiently accurate to serve as the basis for decisions regarding treatment modification. PMID:24286200

  7. Improved medical image modality classification using a combination of visual and textual features.

    PubMed

    Dimitrovski, Ivica; Kocev, Dragi; Kitanovski, Ivan; Loskovska, Suzana; Džeroski, Sašo

    2015-01-01

    In this paper, we present the approach that we applied to the medical modality classification tasks at the ImageCLEF evaluation forum. More specifically, we used the modality classification databases from the ImageCLEF competitions in 2011, 2012 and 2013, described by four visual and one textual types of features, and combinations thereof. We used local binary patterns, color and edge directivity descriptors, fuzzy color and texture histogram and scale-invariant feature transform (and its variant opponentSIFT) as visual features and the standard bag-of-words textual representation coupled with TF-IDF weighting. The results from the extensive experimental evaluation identify the SIFT and opponentSIFT features as the best performing features for modality classification. Next, the low-level fusion of the visual features improves the predictive performance of the classifiers. This is because the different features are able to capture different aspects of an image, their combination offering a more complete representation of the visual content in an image. Moreover, adding textual features further increases the predictive performance. Finally, the results obtained with our approach are the best results reported on these databases so far.

  8. Single photon emission computed tomography: An alternative imaging modality in left ventricular evaluation

    PubMed Central

    Yalçin, Hulya; Maza, Sofiane; Yalçin, Fatih

    2008-01-01

    Various diagnostic imaging modalities have been used for quantitative left ventricular (LV) parameters. Because of the suboptimal value of the most widely used technology, two-dimensional (2D) echocardiography, 3D ultrasonographic imaging has improved accuracy for LV volume and function. Single photon emission computed tomography (SPECT) is another diagnostic method where LV volumetric and functional parameters can be accurately provided by gated myocardial perfusion tomographic slices. First pass radionuclide venticulography is another imaging modality which has some practical limitations. Despite lower ejection fraction (EF) values compared with invasive approach, noninvasive techniques are accurate in determination of normal and depressed EF. Noninvasive techniques with 3D approach including gated SPECT are beneficial for not only global but also regional LV evaluation. It has been mentioned that the slight difference between echocardiography and SPECT could be caused by the diverse population studied. The results of diagnostic stress tests support that SPECT is feasible to use in evaluation of LV volume and functional analysis. Magnetic resonance imaging is an expensive modality to use routinely, but it preserves its importance in selected patients for providing precise LV geometric data. PMID:19183754

  9. MO-AB-BRA-02: A Novel Scatter Imaging Modality for Real-Time Image Guidance During Lung SBRT

    SciTech Connect

    Redler, G; Bernard, D; Templeton, A; Chu, J; Nair, C Kumaran; Turian, J

    2015-06-15

    Purpose: A novel scatter imaging modality is developed and its feasibility for image-guided radiation therapy (IGRT) during stereotactic body radiation therapy (SBRT) for lung cancer patients is assessed using analytic and Monte Carlo models as well as experimental testing. Methods: During treatment, incident radiation interacts and scatters from within the patient. The presented methodology forms an image of patient anatomy from the scattered radiation for real-time localization of the treatment target. A radiographic flat panel-based pinhole camera provides spatial information regarding the origin of detected scattered radiation. An analytical model is developed, which provides a mathematical formalism for describing the scatter imaging system. Experimental scatter images are acquired by irradiating an object using a Varian TrueBeam accelerator. The differentiation between tissue types is investigated by imaging simple objects of known compositions (water, lung, and cortical bone equivalent). A lung tumor phantom, simulating materials and geometry encountered during lung SBRT treatments, is fabricated and imaged to investigate image quality for various quantities of delivered radiation. Monte Carlo N-Particle (MCNP) code is used for validation and testing by simulating scatter image formation using the experimental pinhole camera setup. Results: Analytical calculations, MCNP simulations, and experimental results when imaging the water, lung, and cortical bone equivalent objects show close agreement, thus validating the proposed models and demonstrating that scatter imaging differentiates these materials well. Lung tumor phantom images have sufficient contrast-to-noise ratio (CNR) to clearly distinguish tumor from surrounding lung tissue. CNR=4.1 and CNR=29.1 for 10MU and 5000MU images (equivalent to 0.5 and 250 second images), respectively. Conclusion: Lung SBRT provides favorable treatment outcomes, but depends on accurate target localization. A comprehensive

  10. Simultaneous quadruple modal nonlinear optical imaging for gastric diseases diagnosis and characterization

    NASA Astrophysics Data System (ADS)

    Wang, Zi; Zheng, Wei; Lin, Jian; Huang, Zhiwei

    2015-03-01

    We report the development of a unique simultaneous quadruple-modal nonlinear optical microscopy (i.e., stimulated Raman scattering (SRS), second-harmonic generation (SHG), two-photon excitation fluorescence (TPEF), and third-harmonic generation (THG)) platform for characterization of the gastric diseases (i.e., gastritis, intestinal metaplasia (IM), intestinal type adenocarcinoma). SRS highlights the goblet cells found in IM. SHG images the distribution of collagen in lamina propria. Collagen is found to aggregate for intestinal type adenocarcinoma. TPEF reveals the cell morphology and can reflect the damage inside glands caused by the diseases. THG visualizes the nuclei with high spatial resolution, which facilitates the identification of neutrophils that are usually used as a feature of inflammation. This work shows that the co-registration of quadruple-modal images can be an effective means for diagnosis and characterization of gastric diseases at the cellular and molecular levels.

  11. Cerenkov Luminescence Imaging as a Modality to Evaluate Antibody-Based PET Radiotracers.

    PubMed

    D'Souza, Jimson W; Hensley, Harvey; Doss, Mohan; Beigarten, Charles; Torgov, Michael; Olafsen, Tove; Yu, Jian Q; Robinson, Matthew K

    2017-01-01

    Antibodies, and engineered antibody fragments, labeled with radioisotopes are being developed as radiotracers for the detection and phenotyping of diseases such as cancer. The development of antibody-based radiotracers requires extensive characterization of their in vitro and in vivo properties, including their ability to target tumors in an antigen-selective manner. In this study, we investigated the use of Cerenkov luminescence imaging (CLI) as compared with PET as a modality for evaluating the in vivo behavior of antibody-based radiotracers.

  12. Siloxane nanoprobes for labeling and dual modality imaging of neural stem cells

    PubMed Central

    Addington, Caroline P.; Cusick, Alex; Shankar, Rohini Vidya; Agarwal, Shubhangi; Stabenfeldt, Sarah E.; Kodibagkar, Vikram D.

    2015-01-01

    Cell therapy represents a promising therapeutic for a myriad of medical conditions, including cancer, traumatic brain injury, and cardiovascular disease among others. A thorough understanding of the efficacy and cellular dynamics of these therapies necessitates the ability to non-invasively track cells in vivo. Magnetic resonance imaging (MRI) provides a platform to track cells as a non-invasive modality with superior resolution and soft tissue contrast. We recently reported a new nanoprobe platform for cell labeling and imaging using fluorophore doped siloxane core nanoemulsions as dual modality (1H MRI/Fluorescence), dual-functional (oximetry/detection) nanoprobes. Here, we successfully demonstrate the labeling, dual-modality imaging, and oximetry of neural progenitor/stem cells (NPSCs) in vitro using this platform. Labeling at a concentration of 10 μl/104 cells with a 40%v/v polydimethylsiloxane core nanoemulsion, doped with rhodamine, had minimal effect on viability, no effect on migration, proliferation and differentiation of NPSCs and allowed for unambiguous visualization of labeled NPSCs by 1H MR and fluorescence and local pO2 reporting by labeled NPSCs. This new approach for cell labeling with a positive contrast 1H MR probe has the potential to improve mechanistic knowledge of current therapies, and guide the design of future cell therapies due to its clinical translatability. PMID:26597417

  13. Monitoring of Biological Changes in Electromechanical Reshaping of Cartilage Using Imaging Modalities

    PubMed Central

    Hong, Seok Jin

    2016-01-01

    Electromechanical reshaping (EMR) is a promising surgical technique used to reshape cartilage by direct current and mechanical deformation. It causes local stress relaxation and permanent alterations in the shape of cartilage. The major advantages of EMR are its minimally invasive nature and nonthermal electrochemical mechanism of action. The purpose of this study is to validate that EMR does not cause thermal damage and to observe structural changes in post-EMR cartilage using several imaging modalities. Three imaging modality metrics were used to validate the performance of EMR by identifying structural deformation during cartilage reshaping: infrared thermography was used to sense the temperature of the flat cartilages (16.7°C at 6 V), optical coherence tomography (OCT) was used to examine the change in the cartilage by gauging deformation in the tissue matrix during EMR, and scanning electron microscopy (SEM) was used to show that EMR-treated cartilage is irregularly arranged and the thickness of collagen fibers varies, which affects the change in shape of the cartilage. In conclusion, the three imaging modalities reveal the nonthermal and electromechanical mechanisms of EMR and demonstrate that use of an EMR device is feasible for reshaping cartilage in a minimally invasive manner. PMID:28053987

  14. Monitoring of Biological Changes in Electromechanical Reshaping of Cartilage Using Imaging Modalities.

    PubMed

    Hong, Seok Jin; Lee, Minseok; Oh, Connie J; Kim, Sehwan

    2016-01-01

    Electromechanical reshaping (EMR) is a promising surgical technique used to reshape cartilage by direct current and mechanical deformation. It causes local stress relaxation and permanent alterations in the shape of cartilage. The major advantages of EMR are its minimally invasive nature and nonthermal electrochemical mechanism of action. The purpose of this study is to validate that EMR does not cause thermal damage and to observe structural changes in post-EMR cartilage using several imaging modalities. Three imaging modality metrics were used to validate the performance of EMR by identifying structural deformation during cartilage reshaping: infrared thermography was used to sense the temperature of the flat cartilages (16.7°C at 6 V), optical coherence tomography (OCT) was used to examine the change in the cartilage by gauging deformation in the tissue matrix during EMR, and scanning electron microscopy (SEM) was used to show that EMR-treated cartilage is irregularly arranged and the thickness of collagen fibers varies, which affects the change in shape of the cartilage. In conclusion, the three imaging modalities reveal the nonthermal and electromechanical mechanisms of EMR and demonstrate that use of an EMR device is feasible for reshaping cartilage in a minimally invasive manner.

  15. Additive global cerebral blood flow normalization in arterial spin labeling perfusion imaging.

    PubMed

    Stewart, Stephanie B; Koller, Jonathan M; Campbell, Meghan C; Perlmutter, Joel S; Black, Kevin J

    2015-01-01

    To determine how different methods of normalizing for global cerebral blood flow (gCBF) affect image quality and sensitivity to cortical activation, pulsed arterial spin labeling (pASL) scans obtained during a visual task were normalized by either additive or multiplicative normalization of modal gCBF. Normalization by either method increased the statistical significance of cortical activation by a visual stimulus. However, image quality was superior with additive normalization, whether judged by intensity histograms or by reduced variability within gray and white matter.

  16. Multi-Modality fiducial marker for validation of registration of medical images with histology

    NASA Astrophysics Data System (ADS)

    Shojaii, Rushin; Martel, Anne L.

    2010-03-01

    A multi-modality fiducial marker is presented in this work, which can be used for validating the correlation of histology images with medical images. This marker can also be used for landmark-based image registration. Seven different fiducial markers including a catheter, spaghetti, black spaghetti, cuttlefish ink, and liquid iron are implanted in a mouse specimen and then investigated based on visibility, localization, size, and stability. The black spaghetti and the mixture of cuttlefish ink and flour are shown to be the most suitable markers. Based on the size of the markers, black spaghetti is more suitable for big specimens and the mixture of the cuttlefish ink, flour, and water injected in a catheter is more suitable for small specimens such as mouse tumours. These markers are visible on medical images and also detectable on histology and optical images of the tissue blocks. The main component in these agents which enhances the contrast is iron.

  17. Hybrid anisotropic nanostructures for dual-modal cancer imaging and image-guided chemo-thermo therapies.

    PubMed

    Zhang, Ruiping; Cheng, Kai; Antaris, Alexander L; Ma, Xiaowei; Yang, Min; Ramakrishnan, Sindhuja; Liu, Guifeng; Lu, Alex; Dai, Hongjie; Tian, Mei; Cheng, Zhen

    2016-10-01

    The multimodality theranostic system, which can integrate two or more different therapeutic modalities and multimodal imaging agents into a nanoentity, shows great promising prospects for the cancer treatment. Herein, we developed an efficient and novel strategy to synthesize hybrid anisotropic nanoparticles (HANs) with intrinsic multimodal theranostic capability [chemotherapy, photothermal therapy, magnetic resonance imaging (MRI), and photoacoustic imaging (PAI)]. For the first time, under the guidance of MRI and PAI, the chemotherapy and thermotherapy induced by administration of multifunctional hybrid nanoprobes were applied simultaneously to the treatment of colon cancer-bearing mice in vivo.

  18. Operational modal analysis via image based technique of very flexible space structures

    NASA Astrophysics Data System (ADS)

    Sabatini, Marco; Gasbarri, Paolo; Palmerini, Giovanni B.; Monti, Riccardo

    2013-08-01

    Vibrations represent one of the most important topics of the engineering design relevant to flexible structures. The importance of this problem increases when a very flexible system is considered, and this is often the case of space structures. In order to identify the modal characteristics, in terms of natural frequencies and relevant modal parameters, ground tests are performed. However, these parameters could vary due to the operative conditions of the system. In order to continuously monitor the modal characteristics during the satellite lifetime, an operational modal analysis is mandatory. This kind of analysis is usually performed by using classical accelerometers or strain gauges and by properly analyzing the acquired output. In this paper a different approach for the vibrations data acquisition will be performed via image-based technique. In order to simulate a flexible satellite, a free flying platform is used; the problem is furthermore complicated by the fact that the overall system, constituted by a highly rigid bus and very flexible panels, must necessarily be modeled as a multibody system. In the experimental campaign, the camera, placed on the bus, will be used to identify the eigenfrequencies of the vibrating structure; in this case aluminum thin plates simulate very flexible solar panels. The structure is excited by a hammer or studied during a fast attitude maneuver. The results of the experimental activity will be investigated and compared with respect to the numerical simulation obtained via a FEM-multibody software and the relevant results will be proposed and discussed.

  19. An Optimized Triple Modality Reporter for Quantitative In Vivo Tumor Imaging and Therapy Evaluation

    PubMed Central

    Yang, Jin; Lin, John Y.; Whitney, Michael A.; Nguyen, Quyen T.; Tsien, Roger Y.

    2014-01-01

    We present an optimized triple modality reporter construct combining a far-red fluorescent protein (E2-Crimson), enhanced firefly luciferase enzyme (Luc2), and truncated wild type herpes simplex virus I thymidine kinase (wttk) that allows for sensitive, long-term tracking of tumor growth in vivo by fluorescence, bioluminescence, and positron emission tomography. Two human cancer cell lines (MDA-MB-231 breast cancer and HT-1080 fibrosarcoma cancer) were successfully transduced to express this triple modality reporter. Fluorescence and bioluminescence imaging of the triple modality reporter were used to accurately quantify the therapeutic responses of MDA-MB-231 tumors to the chemotherapeutic agent monomethyl auristatin E in vivo in athymic nude mice. Positive correlation was observed between the fluorescence and bioluminescence signals, and these signals were also positively correlated with the ex vivo tumor weights. This is the first reported use of both fluorescence and bioluminescence signals from a multi-modality reporter construct to measure drug efficacy in vivo. PMID:24816650

  20. A connectivity-based test-retest dataset of multi-modal magnetic resonance imaging in young healthy adults.

    PubMed

    Lin, Qixiang; Dai, Zhengjia; Xia, Mingrui; Han, Zaizhu; Huang, Ruiwang; Gong, Gaolang; Liu, Chao; Bi, Yanchao; He, Yong

    2015-01-01

    Recently, magnetic resonance imaging (MRI) has been widely used to investigate the structures and functions of the human brain in health and disease in vivo. However, there are growing concerns about the test-retest reliability of structural and functional measurements derived from MRI data. Here, we present a test-retest dataset of multi-modal MRI including structural MRI (S-MRI), diffusion MRI (D-MRI) and resting-state functional MRI (R-fMRI). Fifty-seven healthy young adults (age range: 19-30 years) were recruited and completed two multi-modal MRI scan sessions at an interval of approximately 6 weeks. Each scan session included R-fMRI, S-MRI and D-MRI data. Additionally, there were two separated R-fMRI scans at the beginning and at the end of the first session (approximately 20 min apart). This multi-modal MRI dataset not only provides excellent opportunities to investigate the short- and long-term test-retest reliability of the brain's structural and functional measurements at the regional, connectional and network levels, but also allows probing the test-retest reliability of structural-functional couplings in the human brain.

  1. Rapid fabrication of carbon quantum dots as multifunctional nanovehicles for dual-modal targeted imaging and chemotherapy.

    PubMed

    Chiu, Sheng-Hui; Gedda, Gangaraju; Girma, Wubshet Mekonnen; Chen, Jem-Kun; Ling, Yong-Chien; Ghule, Anil V; Ou, Keng-Liang; Chang, Jia-Yaw

    2016-12-01

    Herein, we synthesized an S, N, and Gd tri-element doped magnetofluorescent carbon quantum dots (GdNS@CQDs) within 10min by using a one-pot microwave method. Our results showed that these magnetofluorescent GdNS@CQDs have excellent fluorescent and magnetic properties. Moreover, GdNS@CQDs exhibited high stability at physiological conditions and ionic strength. These magnetofluorescent GdNS@CQDs were conjugated with a folic acid, denoted as FA-GdNS@CQDs, for targeting dual modal fluorescence/magnetic resonance (MR) imaging. The in vitro and in vivo studies confirmed the high biocompatibility and low toxicity of FA-GdNS@CQDs. FA-GdNS@CQDs enhanced the MR response as compared to that for commercial Gd-DTPA. The targeting capabilities of FA-GdNS@CQDs were confirmed in HeLa and HepG2 cells using in vitro fluorescence and MR dual modality imaging. Additionally, an anticancer drug, doxorubicin, was incorporated into the FA-GdNS@CQDs forming FA-GdNS@CQDs-DOX, which enables targeted drug delivery. Importantly, the prepared FA-GdNS@CQDs-DOX showed a high quantity of doxorubicin loading capacity (about 80%) and pH-sensitive drug release. The uptake into cancer cells and the intracellular location of the FA-GdNS@CQDs were observed by confocal laser scanning microscopy. We also successfully demonstrated in vivo fluorescence bio imaging of the FA-GdNS@CQDs, using zebrafish as an animal model.

  2. Dual-modality brain PET-CT image segmentation based on adaptive use of functional and anatomical information.

    PubMed

    Xia, Yong; Eberl, Stefan; Wen, Lingfeng; Fulham, Michael; Feng, David Dagan

    2012-01-01

    Dual medical imaging modalities, such as PET-CT, are now a routine component of clinical practice. Medical image segmentation methods, however, have generally only been applied to single modality images. In this paper, we propose the dual-modality image segmentation model to segment brain PET-CT images into gray matter, white matter and cerebrospinal fluid. This model converts PET-CT image segmentation into an optimization process controlled simultaneously by PET and CT voxel values and spatial constraints. It is innovative in the creation and application of the modality discriminatory power (MDP) coefficient as a weighting scheme to adaptively combine the functional (PET) and anatomical (CT) information on a voxel-by-voxel basis. Our approach relies upon allowing the modality with higher discriminatory power to play a more important role in the segmentation process. We compared the proposed approach to three other image segmentation strategies, including PET-only based segmentation, combination of the results of independent PET image segmentation and CT image segmentation, and simultaneous segmentation of joint PET and CT images without an adaptive weighting scheme. Our results in 21 clinical studies showed that our approach provides the most accurate and reliable segmentation for brain PET-CT images.

  3. Differential diagnosis of adrenal mass using imaging modality: special emphasis on f-18 fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography.

    PubMed

    Lee, Hong Je; Lee, Jaetae

    2014-03-01

    Adrenal incidentalomas are adrenal masses serendipitously detected during an imaging study performed for reasons unrelated to suspicion of adrenal disease. The incidence of adrenal incidentalomas has increased because of the widespread use of various imaging modalities. In oncology patients with adrenal incidentalomas, the characterization of the adrenal masses is challenging because nearly 50% of incidental adrenal masses are metastatic lesions that need special medical attention. Although unenhanced computed tomography (CT) densitometry, chemical shift magnetic resonance imaging (MRI), delayed contrast-enhanced CT and CT histogram analysis have been used as sensitive and specific modalities for differentiating benign from malignant adrenal masses, F-18 fluoro-2-deoxy-D-glucose positron emission tomography (F-18 FDG PET)/CT is a highly accurate imaging modality compared to CT or MRI, especially when these two imaging modalities are combined. In addition, a semiquantitative analysis using standardized uptake value ratio further improves the diagnostic accuracy of F-18 FDG PET/CT in differentiating benign from malignant adrenal masses. Thus, F-18 FDG PET/CT is very helpful for determining the best therapeutic management, especially for assessing the need for surgery.

  4. A supramolecular material for dual-modal imaging and targeted cancer therapy.

    PubMed

    Guan, Shanyue; Liang, Ruizheng; Li, Chunyang; Wei, Min

    2017-04-01

    Recently, how to design a formulation system with simultaneous diagnosis and therapy toward cancer has attracted tremendous attention. Herein, a supramolecular material was prepared via a facile method by the co-intercalation of folic acid (FA) and doxorubicin (DOX) into the gallery of Gd(3+)-doped layered double hydroxides (LDHs), followed by surface adsorption of fluorescein isothiocyanate (FITC). This supramolecular agent was proved to exhibit excellent magnetic resonance imaging (MRI) and fluorescence imaging (FI) behavior, as well as chemotherapy toward cancer (KB cell). The co-intercalated FA enables an efficient and selective drug delivery with good specificity. This work provides a facile approach for the fabrication of a drug formulation with dual-modal imaging and targeted therapy, which could be potentially used in the practical chemotherapy and medical imaging.

  5. mMaple: A Photoconvertible Fluorescent Protein for Use in Multiple Imaging Modalities

    PubMed Central

    McEvoy, Ann L.; Hoi, Hiofan; Bates, Mark; Platonova, Evgenia; Cranfill, Paula J.; Baird, Michelle A.; Davidson, Michael W.; Ewers, Helge; Liphardt, Jan; Campbell, Robert E.

    2012-01-01

    Recent advances in fluorescence microscopy have extended the spatial resolution to the nanometer scale. Here, we report an engineered photoconvertible fluorescent protein (pcFP) variant, designated as mMaple, that is suited for use in multiple conventional and super-resolution imaging modalities, specifically, widefield and confocal microscopy, structured illumination microscopy (SIM), and single-molecule localization microscopy. We demonstrate the versatility of mMaple by obtaining super-resolution images of protein organization in Escherichia coli and conventional fluorescence images of mammalian cells. Beneficial features of mMaple include high photostability of the green state when expressed in mammalian cells and high steady state intracellular protein concentration of functional protein when expressed in E. coli. mMaple thus enables both fast live-cell ensemble imaging and high precision single molecule localization for a single pcFP-containing construct. PMID:23240015

  6. Multi-modal contrast of tissue anatomy enables correlative biomarker imaging

    NASA Astrophysics Data System (ADS)

    Garsha, Karl; Ventura, Franklin; Pestano, Gary; Otter, Michael; Nagy, Dea; Nagle, Ray B.; Roberts, Esteban; Barnes, Michael

    2015-03-01

    Optical imaging techniques are being developed that promise to increase the information content related to specific molecular reporters. Such modalities do not produce contrast in the structural context of the surrounding tissue, making it difficult to reconcile molecular information with morphological context. We report a solution that enables visualization of the tissue morphology on formalin-fixed, paraffin embedded sections prepared for analytical biomarker imaging. Our approach combines modes of transmitted darkfield and fluorescence contrast and computer visualization to produce 2-component image data analogous to the classical hematoxylin and eosin histological stain. An interferometric hyperspectral image capture mode enables measurement of multiplexed biomarkers in annotated anatomic regions. The system enables practical correlative analysis of molecular changes within areas of anatomic pathology.

  7. Imaging of oxygenation in 3D tissue models with multi-modal phosphorescent probes

    NASA Astrophysics Data System (ADS)

    Papkovsky, Dmitri B.; Dmitriev, Ruslan I.; Borisov, Sergei

    2015-03-01

    Cell-penetrating phosphorescence based probes allow real-time, high-resolution imaging of O2 concentration in respiring cells and 3D tissue models. We have developed a panel of such probes, small molecule and nanoparticle structures, which have different spectral characteristics, cell penetrating and tissue staining behavior. The probes are compatible with conventional live cell imaging platforms and can be used in different detection modalities, including ratiometric intensity and PLIM (Phosphorescence Lifetime IMaging) under one- or two-photon excitation. Analytical performance of these probes and utility of the O2 imaging method have been demonstrated with different types of samples: 2D cell cultures, multi-cellular spheroids from cancer cell lines and primary neurons, excised slices from mouse brain, colon and bladder tissue, and live animals. They are particularly useful for hypoxia research, ex-vivo studies of tissue physiology, cell metabolism, cancer, inflammation, and multiplexing with many conventional fluorophors and markers of cellular function.

  8. One step synthesis of quantum dot-magnetic nanoparticle heterodimers for dual modal imaging applications.

    PubMed

    Lee, Jiyeon; Hwang, Gyoyeon; Hong, Yeon Sun; Sim, Taebo

    2015-04-21

    Dual modal nanoprobes are promising tools for accurately detecting target molecules as part of the diagnosis of diseases including cancers. We have explored a new dual modal bioimaging probe that is comprised of a quantum dot (QD)-magnetic nanoparticle (MNP) hybrid. The MNP-QD heterodimers explored are fabricated by using a platinum-guanine coordination bonding guided self-assembly process, employing the metal-DNA conjugation method. Investigations utilizing energy dispersive spectroscopy (EDS) equipped high resolution transmission electron microscopy (HRTEM) demonstrate that the heterodimer contains an iron (Fe) dominant MNP and a cadmium (Cd) dominant QD. Finally, the results of cell studies show that the MNP-QD conjugates display good HeLa cell uptake in the absence of non-specific binding to the cell membrane and, as such, they can be used to label cells in vitro and in vivo as part of a new cell imaging technique.

  9. Evaluation of clip localization for different kilovoltage imaging modalities as applied to partial breast irradiation setup

    SciTech Connect

    Buehler, Andreas; Ng, Sook-Kien; Lyatskaya, Yulia; Stsepankou, Dzmitry; Hesser, Jurgen; Zygmanski, Piotr

    2009-03-15

    Surgical clip localization and image quality were evaluated for different types of kilovoltage cone beam imaging modalities as applied to partial breast irradiation (PBI) setup. These modalities included (i) clinically available radiographs and cone beam CT (CB-CT) and (ii) various alternative modalities based on partial/sparse/truncated CB-CT. An anthropomorphic torso-breast phantom with surgical clips was used for the imaging studies. The torso phantom had artificial lungs, and the attached breast phantom was a mammographic phantom with realistic shape and tissue inhomogeneities. Three types of clips of variable size were used in two orthogonal orientations to assess their in-/cross-plane characteristics for image-guided setup of the torso-breast phantom in supine position. All studies were performed with the Varian on-board imaging (OBI, Varian) system. CT reconstructions were calculated with the standard Feldkamp-Davis-Kress algorithm. First, the radiographs were studied for a wide range of viewing angles to characterize image quality for various types of body anatomy in the foreground/background of the clips. Next, image reconstruction quality was evaluated for partial/sparse/truncated CB-CT. Since these modalities led to reconstructions with strong artifacts due to insufficient input data, a knowledge-based CT reconstruction method was also tested. In this method, the input data to the reconstruction algorithm were modified by combining complementary data sets selected from the treatment and reference projections. Different partial/sparse/truncated CB-CT scan types were studied depending on the total arc angle, angular increment between the consequent views (CT projections), orientation of the arc center with respect to the imaged breast and chest wall, and imaging field size. The central angles of the viewing arcs were either tangential or orthogonal to the chest wall. Several offset positions of the phantom with respect to the reference position were

  10. High near-infrared absorbing Cu5FeS4 nanoparticles for dual-modal imaging and photothermal therapy

    NASA Astrophysics Data System (ADS)

    Zhao, Qi; Yi, Xuan; Li, Meifang; Zhong, Xiaoyan; Shi, Quanliang; Yang, Kai

    2016-07-01

    Multifunctional nanomaterials have shown excellent and promising properties for cancer diagnosis and treatment. Herein, we have developed iron doped copper sulfide (Cu5FeS4) nanoparticles with a non-covalent polyethylene glycol (PEG) coating (Cu5FeS4-PEG) for tumor dual-modal imaging and photothermal therapy (PTT). The obtained Cu5FeS4-PEG nanoparticles with high near-infrared absorbance could be used for phototoacoustic (PA) imaging and PTT, whereas Fe3+ doping offer the nanoparticles the additional property for magnetic resonance (MR) imaging. As shown by PA imaging, Cu5FeS4-PEG exhibit a high tumor uptake (~10% ID g-1) after intravenous injection. In vitro and in vivo cancer treatment further confirm that Cu5FeS4-PEG could act as a novel therapeutic agent for PTT of cancer cells. Our study further promotes the potential applications of multifunctional nanomaterials in a range of tumor diagnoses and treatments.Multifunctional nanomaterials have shown excellent and promising properties for cancer diagnosis and treatment. Herein, we have developed iron doped copper sulfide (Cu5FeS4) nanoparticles with a non-covalent polyethylene glycol (PEG) coating (Cu5FeS4-PEG) for tumor dual-modal imaging and photothermal therapy (PTT). The obtained Cu5FeS4-PEG nanoparticles with high near-infrared absorbance could be used for phototoacoustic (PA) imaging and PTT, whereas Fe3+ doping offer the nanoparticles the additional property for magnetic resonance (MR) imaging. As shown by PA imaging, Cu5FeS4-PEG exhibit a high tumor uptake (~10% ID g-1) after intravenous injection. In vitro and in vivo cancer treatment further confirm that Cu5FeS4-PEG could act as a novel therapeutic agent for PTT of cancer cells. Our study further promotes the potential applications of multifunctional nanomaterials in a range of tumor diagnoses and treatments. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr04444a

  11. Optical and photoacoustic dual-modality imaging guided synergistic photodynamic/photothermal therapies

    NASA Astrophysics Data System (ADS)

    Yan, Xuefeng; Hu, Hao; Lin, Jing; Jin, Albert J.; Niu, Gang; Zhang, Shaoliang; Huang, Peng; Shen, Baozhong; Chen, Xiaoyuan

    2015-01-01

    Phototherapies such as photodynamic therapy (PDT) and photothermal therapy (PTT), due to their specific spatiotemporal selectivity and minimal invasiveness, have been widely investigated as alternative treatments of malignant diseases. Graphene and its derivatives not only have been used as carriers to deliver photosensitizers for PDT, but also as photothermal conversion agents (PTCAs) for PTT. Herein, we strategically designed and produced a novel photo-theranostic platform based on sinoporphyrin sodium (DVDMS) photosensitizer-loaded PEGylated graphene oxide (GO-PEG-DVDMS) for enhanced fluorescence/photoacoustic (PA) dual-modal imaging and combined PDT and PTT. The GO-PEG carrier drastically improves the fluorescence of loaded DVDMS via intramolecular charge transfer. Concurrently, DVDMS significantly enhances the near-infrared (NIR) absorption of GO for improved PA imaging and PTT. The cancer theranostic capability of the as-prepared GO-PEG-DVDMS was carefully investigated both in vitro and in vivo. This novel theranostics is well suited for fluorescence/PA dual-modal imaging and synergistic PDT/PTT.

  12. Optical and photoacoustic dual-modality imaging guided synergistic photodynamic/photothermal therapies.

    PubMed

    Yan, Xuefeng; Hu, Hao; Lin, Jing; Jin, Albert J; Niu, Gang; Zhang, Shaoliang; Huang, Peng; Shen, Baozhong; Chen, Xiaoyuan

    2015-02-14

    Phototherapies such as photodynamic therapy (PDT) and photothermal therapy (PTT), due to their specific spatiotemporal selectivity and minimal invasiveness, have been widely investigated as alternative treatments of malignant diseases. Graphene and its derivatives not only have been used as carriers to deliver photosensitizers for PDT, but also as photothermal conversion agents (PTCAs) for PTT. Herein, we strategically designed and produced a novel photo-theranostic platform based on sinoporphyrin sodium (DVDMS) photosensitizer-loaded PEGylated graphene oxide (GO-PEG-DVDMS) for enhanced fluorescence/photoacoustic (PA) dual-modal imaging and combined PDT and PTT. The GO-PEG carrier drastically improves the fluorescence of loaded DVDMS via intramolecular charge transfer. Concurrently, DVDMS significantly enhances the near-infrared (NIR) absorption of GO for improved PA imaging and PTT. The cancer theranostic capability of the as-prepared GO-PEG-DVDMS was carefully investigated both in vitro and in vivo. This novel theranostics is well suited for fluorescence/PA dual-modal imaging and synergistic PDT/PTT.

  13. MINC 2.0: A Flexible Format for Multi-Modal Images

    PubMed Central

    Vincent, Robert D.; Neelin, Peter; Khalili-Mahani, Najmeh; Janke, Andrew L.; Fonov, Vladimir S.; Robbins, Steven M.; Baghdadi, Leila; Lerch, Jason; Sled, John G.; Adalat, Reza; MacDonald, David; Zijdenbos, Alex P.; Collins, D. Louis; Evans, Alan C.

    2016-01-01

    It is often useful that an imaging data format can afford rich metadata, be flexible, scale to very large file sizes, support multi-modal data, and have strong inbuilt mechanisms for data provenance. Beginning in 1992, MINC was developed as a system for flexible, self-documenting representation of neuroscientific imaging data with arbitrary orientation and dimensionality. The MINC system incorporates three broad components: a file format specification, a programming library, and a growing set of tools. In the early 2000's the MINC developers created MINC 2.0, which added support for 64-bit file sizes, internal compression, and a number of other modern features. Because of its extensible design, it has been easy to incorporate details of provenance in the header metadata, including an explicit processing history, unique identifiers, and vendor-specific scanner settings. This makes MINC ideal for use in large scale imaging studies and databases. It also makes it easy to adapt to new scanning sequences and modalities. PMID:27563289

  14. In vivo monitoring of structural and mechanical changes of tissue scaffolds by multi-modality imaging

    PubMed Central

    Park, Dae Woo; Ye, Sang-Ho; Jiang, Hong Bin; Dutta, Debaditya; Nonaka, Kazuhiro; Wagner, William R.; Kim, Kang

    2014-01-01

    Degradable tissue scaffolds are implanted to serve a mechanical role while healing processes occur and putatively assume the physiological load as the scaffold degrades. Mechanical failure during this period can be unpredictable as monitoring of structural degradation and mechanical strength changes at the implant site is not readily achieved in vivo, and non-invasively. To address this need, a multi-modality approach using ultrasound shear wave imaging (USWI) and photoacoustic imaging (PAI) for both mechanical and structural assessment in vivo was demonstrated with degradable poly(ester urethane)urea (PEUU) and polydioxanone (PDO) scaffolds. The fibrous scaffolds were fabricated with wet electrospinning, dyed with indocyanine green (ICG) for optical contrast in PAI, and implanted in the abdominal wall of 36 rats. The scaffolds were monitored monthly using USWI and PAI and were extracted at 0, 4, 8 and 12 wk for mechanical and histological assessment. The change in shear modulus of the constructs in vivo obtained by USWI correlated with the change in average Young's modulus of the constructs ex vivo obtained by compression measurements. The PEUU and PDO scaffolds exhibited distinctly different degradation rates and average PAI signal intensity. The distribution of PAI signal intensity also corresponded well to the remaining scaffolds as seen in explant histology. This evidence using a small animal abdominal wall repair model demonstrates that multi-modality imaging of USWI and PAI may allow tissue engineers to noninvasively evaluate concurrent mechanical stiffness and structural changes of tissue constructs in vivo for a variety of applications. PMID:24951048

  15. Molecular Platform for Design and Synthesis of Targeted Dual-Modality Imaging Probes

    PubMed Central

    2015-01-01

    We report a versatile dendritic structure based platform for construction of targeted dual-modality imaging probes. The platform contains multiple copies of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) branching out from a 1,4,7-triazacyclononane-N,N′,N″-triacetic acid (NOTA) core. The specific coordination chemistries of the NOTA and DOTA moieties offer specific loading of 68/67Ga3+ and Gd3+, respectively, into a common molecular scaffold. The platform also contains three amino groups which can potentiate targeted dual-modality imaging of PET/MRI or SPECT/MRI (PET: positron emission tomography; SPECT: single photon emission computed tomography; MRI: magnetic resonance imaging) when further functionalized by targeting vectors of interest. To validate this design concept, a bimetallic complex was synthesized with six peripheral Gd-DOTA units and one Ga-NOTA core at the center, whose ion T1 relaxivity per gadolinium atom was measured to be 15.99 mM–1 s–1 at 20 MHz. Further, the bimetallic agent demonstrated its anticipated in vivo stability, tissue distribution, and pharmacokinetic profile when labeled with 67Ga. When conjugated with a model targeting peptide sequence, the trivalent construct was able to visualize tumors in a mouse xenograft model by both PET and MRI via a single dose injection. PMID:25615011

  16. Continuous multi-modality brain imaging reveals modified neurovascular seizure response after intervention

    PubMed Central

    Ringuette, Dene; Jeffrey, Melanie A.; Dufour, Suzie; Carlen, Peter L.; Levi, Ofer

    2017-01-01

    We developed a multi-modal brain imaging system to investigate the relationship between blood flow, blood oxygenation/volume, intracellular calcium and electrographic activity during acute seizure-like events (SLEs), both before and after pharmacological intervention. Rising blood volume was highly specific to SLE-onset whereas blood flow was more correlated with all eletrographic activity. Intracellular calcium spiked between SLEs and at SLE-onset with oscillation during SLEs. Modified neurovascular and ionic SLE responses were observed after intervention and the interval between SLEs became shorter and more inconsistent. Comparison of artery and vein pulsatile flow suggest proximal interference and greater vascular leakage prior to intervention. PMID:28270990

  17. Multi-Modal Imaging with a Toolbox of Influenza A Reporter Viruses.

    PubMed

    Tran, Vy; Poole, Daniel S; Jeffery, Justin J; Sheahan, Timothy P; Creech, Donald; Yevtodiyenko, Aleksey; Peat, Andrew J; Francis, Kevin P; You, Shihyun; Mehle, Andrew

    2015-10-13

    Reporter viruses are useful probes for studying multiple stages of the viral life cycle. Here we describe an expanded toolbox of fluorescent and bioluminescent influenza A reporter viruses. The enhanced utility of these tools enabled kinetic studies of viral attachment, infection, and co-infection. Multi-modal bioluminescence and positron emission tomography-computed tomography (PET/CT) imaging of infected animals revealed that antiviral treatment reduced viral load, dissemination, and inflammation. These new technologies and applications will dramatically accelerate in vitro and in vivo influenza virus studies.

  18. Dual modality photothermal OCT and magnetic resonance imaging with carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Tucker-Schwartz, Jason M.; Hong, Tu; Colvin, Daniel C.; Xu, Yaqiong; Skala, Melissa C.

    2012-03-01

    Preclinical molecular imaging of cancer has the potential to increase the understanding of fundamental cancer biology, elucidate mechanisms of cancer treatment resistance, and increase effectiveness of drug candidates. Optical and magnetic resonance imaging contain complementary strengths, suitable for gaining a wealth of knowledge when combined. Here, we demonstrate the inherent contrast sensitivity of single walled carbon nanotubes to absorption based photothermal optical coherence tomography (PT-OCT), and magnetic resonance imaging spin dephasing contrast (T2). A spectral-domain OCT system was interfaced with an amplitude-modulated (100 Hz) titanium sapphire pump beam for PT-OCT imaging. MRI was performed with a commercial 4.7 T animal scanner. With both imaging tools, contrast agent signal linearity (r2 > 0.95) and nM sensitivity over background (p < 0.05) was experimentally determined with serially dilute solutions of carbon nanotubes coated in amine-terminated polyethylene glycol. The surface functionalization chemistry for carbon nanotubes is well understood, and molecular targeting has been demonstrated in vitro and in vivo, making carbon nanotubes an attractive agent for molecular imaging in preclinical models. We have demonstrated the initial characterization steps for using carbon nanotubes for multi-modality imaging with PT-OCT and MRI.

  19. A dual modality phantom for cone beam CT and ultrasound image fusion in prostate implant

    SciTech Connect

    Ng, Angela; Beiki-Ardakan, Akbar; Tong, Shidong; Moseley, Douglas; Siewerdsen, Jeffrey; Jaffray, David; Yeung, Ivan W. T.

    2008-05-15

    In transrectal ultrasound (TRUS) guided prostate seed brachytherapy, TRUS provides good delineation of the prostate while x-ray imaging, e.g., C-arm, gives excellent contrast for seed localization. With the recent availability of cone beam CT (CBCT) technology, the combination of the two imaging modalities may provide an ideal system for intraoperative dosimetric feedback during implantation. A dual modality phantom made of acrylic and copper wire was designed to measure the accuracy and precision of image coregistration between a C-arm based CBCT and 3D TRUS. The phantom was scanned with TRUS and CBCT under the same setup condition. Successive parallel transverse ultrasound (US) images were acquired through manual stepping of the US probe across the phantom at an increment of 1 mm over 7.5 cm. The CBCT imaging was done with three reconstructed slice thicknesses (0.4, 0.8, and 1.6 mm) as well as at three different tilt angles (0 deg., 15 deg., 30 deg. ), and the coregistration between CBCT and US images was done using the Variseed system based on four fiducial markers. Fiducial localization error (FLE), fiducial registration error (FRE), and target registration error (TRE) were calculated for all registered image sets. Results showed that FLE were typically less than 0.4 mm, FRE were less than 0.5 mm, and TRE were typically less than 1 mm within the range of operation for prostate implant (i.e., <6 cm to surface of US probe). An analysis of variance test showed no significant difference in TRE for the CBCT-US fusion among the three slice thicknesses (p=0.37). As a comparison, the experiment was repeated with a US-conventional CT scanner combination. No significant difference in TRE was noted between the US-conventional CT fusion and that for all three CBCT image slice thicknesses (p=0.21). CBCT imaging was also performed at three different C-arm tilt angles of 0 deg., 15 deg., and 30 deg. and reconstructed at a slice thickness of 0.8 mm. There is no significant

  20. Dual modal in vivo imaging using upconversion luminescence and enhanced computed tomography properties

    NASA Astrophysics Data System (ADS)

    Zhang, Guo; Liu, Yanlan; Yuan, Qinghai; Zong, Chenghua; Liu, Jianhua; Lu, Lehui

    2011-10-01

    In vivo upconversion luminescence (UCL) imaging, exhibiting favorable characteristics such as high photostability, no blinking, sharp emission lines, and long lifetimes, is recognized as the excellent and significant photoluminescence imaging for the future. To develop the imaging system with high visual sensitivity and tissue penetration, the functional molecules with X-ray computed tomography (CT) contrast were grafted onto upconversion nanoparticles to obtain β-NaYF4:18% Yb3+,2%Er3+@SiO2-I/PEG (UCNPs@SiO2-I/PEG) nanoprobes. These nanoprobes are water-soluble, have low cytotoxicity, and possess excellent UCL and remarkable CT contrast. Of particular note is that, besides the element iodine, rare earth elements (Y, Yb, and Er) present in the nanoprobes also show CT contrast. Moreover, no background autofluorescence signal is found in in vivo UCL images. We believe that these nanoprobes with dual modal in vivo imaging of UCL and CT can serve as a promising platform for clinical diagnosis or biomedical studies.In vivo upconversion luminescence (UCL) imaging, exhibiting favorable characteristics such as high photostability, no blinking, sharp emission lines, and long lifetimes, is recognized as the excellent and significant photoluminescence imaging for the future. To develop the imaging system with high visual sensitivity and tissue penetration, the functional molecules with X-ray computed tomography (CT) contrast were grafted onto upconversion nanoparticles to obtain β-NaYF4:18% Yb3+,2%Er3+@SiO2-I/PEG (UCNPs@SiO2-I/PEG) nanoprobes. These nanoprobes are water-soluble, have low cytotoxicity, and possess excellent UCL and remarkable CT contrast. Of particular note is that, besides the element iodine, rare earth elements (Y, Yb, and Er) present in the nanoprobes also show CT contrast. Moreover, no background autofluorescence signal is found in in vivo UCL images. We believe that these nanoprobes with dual modal in vivo imaging of UCL and CT can serve as a promising

  1. In vivo dual-modality imaging of lymphatic systems using indocyanine green in rats: three-dimensional photoacoustic imaging and planar fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Kim, Chulhong; Song, Kwang Hyun; Wang, Lihong V.

    2010-02-01

    The purpose of this study is to map non-invasively sentinel lymph nodes (SLNs) and lymphatic vessels of rats in vivo using FDA-approved indocyanine green (ICG) and two non-ionizing imaging modalities: volumetric spectroscopic photoacoustic (PA) imaging, which measures optical absorption, and planar fluorescence imaging, which measures fluorescent emission. SLNs and lymphatic vessels were clearly visible after a 0.2 ml-intradermal-injection of 1 mM ICG in both imaging systems. We also imaged deeply positioned lymph nodes in vivo by layering biological tissues on top of rats. These two modalities, when used together with ICG, have the potential to map SLNs in axillary staging and to study tumor metastasis in breast cancer patients.

  2. Multi-modality optical tomography for simultaneous morphological and molecular imaging

    NASA Astrophysics Data System (ADS)

    Yuan, Shuai; Li, Qian; Chen, Yu

    2009-11-01

    Optical coherence tomography (OCT) is an emerging medical imaging technology that can generate high resolution cross-sectional imaging (1-2 mm in depth) of tissue microstructure in situ and in real time. Fluorescence imaging provides tissue biochemical, metabolism, and molecular information by measuring fluorescence intensity or spectroscopy of either intrinsic fluorophores or exogenous contrast agents. The combination of these two modalities provides complementary morphological, functional and molecular information to comprehensively assess tissue status. There is a great interest to further extend the fluorescence imaging into tomography in order to provide depth-resolved molecular function that can be coregistered with 3-D tissue morphology provided by OCT. In this paper, we present a combined OCT and line-scanning fluorescence laminar optical tomography (FLOT) system for simultaneous 3-D morphological and molecular imaging with 10-100 μm resolution and millimeter-scale imaging depth. Co-registration on a capillary phantom with fluorescence dye Cy5.5 using the system has been demonstrated.

  3. Graphene oxide-BaGdF5 nanocomposites for multi-modal imaging and photothermal therapy.

    PubMed

    Zhang, Hao; Wu, Huixia; Wang, Jun; Yang, Yan; Wu, Dongmei; Zhang, Yingjian; Zhang, Yang; Zhou, Zhiguo; Yang, Shiping

    2015-02-01

    By using a solvothermal method in the presence of polyethylene glycol (PEG), BaGdF5 nanoparticles are firmly attached on the surface of graphene oxide (GO) nanosheets to form the GO/BaGdF5/PEG nanocomposites. The resulting GO/BaGdF5/PEG shows low cytotoxicity, positive magnetic resonance (MR) contrast effect and better X-ray attenuation property than Iohexol, which enables effective dual-modality MR and X-ray computed tomography (CT) imaging of the tumor model in vivo. The enhanced near-infrared absorbance, good photothermal stability and efficient tumor passive targeting of GO/BaGdF5/PEG result in the highly efficient photothermal ablation of tumor in vivo after intravenous injection of GO/BaGdF5/PEG and the following 808-nm laser irradiation (0.5 W/cm(2)). The histological and biochemical analysis data reveal no perceptible toxicity of GO/BaGdF5/PEG in mice after treatment. These results indicate potential application of GO/BaGdF5/PEG in dual-modality MR/CT imaging and photothermal therapy of cancers.

  4. Tumor Lysing Genetically Engineered T Cells Loaded with Multi-Modal Imaging Agents

    NASA Astrophysics Data System (ADS)

    Bhatnagar, Parijat; Alauddin, Mian; Bankson, James A.; Kirui, Dickson; Seifi, Payam; Huls, Helen; Lee, Dean A.; Babakhani, Aydin; Ferrari, Mauro; Li, King C.; Cooper, Laurence J. N.

    2014-03-01

    Genetically-modified T cells expressing chimeric antigen receptors (CAR) exert anti-tumor effect by identifying tumor-associated antigen (TAA), independent of major histocompatibility complex. For maximal efficacy and safety of adoptively transferred cells, imaging their biodistribution is critical. This will determine if cells home to the tumor and assist in moderating cell dose. Here, T cells are modified to express CAR. An efficient, non-toxic process with potential for cGMP compliance is developed for loading high cell number with multi-modal (PET-MRI) contrast agents (Super Paramagnetic Iron Oxide Nanoparticles - Copper-64; SPION-64Cu). This can now be potentially used for 64Cu-based whole-body PET to detect T cell accumulation region with high-sensitivity, followed by SPION-based MRI of these regions for high-resolution anatomically correlated images of T cells. CD19-specific-CAR+SPIONpos T cells effectively target in vitro CD19+ lymphoma.

  5. Multi-Modal Ultra-Widefield Imaging Features in Waardenburg Syndrome

    PubMed Central

    Choudhry, Netan; Rao, Rajesh C.

    2015-01-01

    Background Waardenburg syndrome is characterized by a group of features including; telecanthus, a broad nasal root, synophrys of the eyebrows, piedbaldism, heterochromia irides, and deaf-mutism. Hypopigmentation of the choroid is a unique feature of this condition examined with multi-modal Ultra-Widefield Imaging in this report. Material/Methods Report of a single case. Results Bilateral symmetric choroidal hypopigmentation was observed with hypoautofluorescence in the region of hypopigmentation. Fluorescein angiography revealed a normal vasculature, however a thickened choroid was seen on Enhanced-Depth Imaging Spectral-Domain OCT (EDI SD-OCT). Conclusion(s) Choroidal hypopigmentation is a unique feature of Waardenburg syndrome, which can be visualized with ultra-widefield fundus autofluorescence. The choroid may also be thickened in this condition and its thickness measured with EDI SD-OCT. PMID:26114849

  6. Multi-modal digital holographic microscopy for wide-field fluorescence and 3D phase imaging

    NASA Astrophysics Data System (ADS)

    Quan, Xiangyu; Xia, Peng; Matoba, Osamu; Nitta, Koichi; Awatsuji, Yasuhiro

    2016-03-01

    Multi-modal digital holographic microscopy is a combination of epifluorescence microscopy and digital holographic microscopy, the main function of which is to obtain images from fluorescence intensity and quantified phase contrasts, simultaneously. The proposed system is mostly beneficial to biological studies, with the reason that often the studies are depending on fluorescent labeling techniques to detect certain intracellular molecules, while phase information reflecting properties of unstained transparent elements. This paper is presenting our latest researches on applications such as randomly moving micro-fluorescent beads and living cells of Physcomitrella patens. The experiments are succeeded on obtaining a succession of wide-field fluorescent images and holograms from micro-beads, and different depths focusing is realized via numerical reconstruction. Living cells of Physcomitrella patens are recorded in the static manner, the reconstruction distance indicates thickness of cellular structure. These results are implementing practical applications toward many biomedical science researches.

  7. Emerging Cardiac Imaging Modalities for the Early Detection of Cardiotoxicity due to Anticancer Therapies.

    PubMed

    López-Fernández, Teresa; Thavendiranathan, Paaladinesh

    2017-02-08

    The undeniable advances in the field of oncology have finally led to a decrease in overall cancer-related mortality. However, this population of long-term cancer survivors is now facing a shift toward a substantial increase in cardiovascular morbidity and mortality. Because the development of overt cardiotoxicity can be associated with poor outcomes, preclinical identification of cardiac toxicity is important. This will promote early instauration of treatments to prevent overt heart dysfunction and allow oncologists to continue cancer therapy in an uninterrupted manner. Surveillance strategies for the early detection of cardiac injury include cardiac imaging and biomarkers during treatment. In this review, we outline existing cardiac imaging modalities to detect myocardial changes in patients undergoing cancer treatment and in survivors, and their strengths and limitations.

  8. Magnetic Resonance Imaging and Other Imaging Modalities in Diagnostic and Tumor Response Evaluation.

    PubMed

    Lambregts, Doenja M J; Maas, Monique; Stokkel, Marcel P M; Beets-Tan, Regina G H

    2016-07-01

    Functional imaging is emerging as a valuable contributor to the clinical management of patients with rectal cancer. Techniques such as diffusion-weighted magnetic resonance imaging, perfusion imaging, and positron emission tomography can offer meaningful insights into tissue architecture, vascularity, and metabolism. Moreover, new techniques targeting other aspects of tumor biology are now being developed and studied. This study reviews the potential role of functional imaging for the diagnosis, treatment monitoring, and assessment of prognosis in patients with rectal cancer.

  9. Emerging roles for integrated imaging modalities in cardiovascular cell-based therapeutics: a clinical perspective

    PubMed Central

    Psaltis, Peter J.; Simari, Robert D.

    2012-01-01

    Despite preclinical promise, the progress of cell-based therapy to clinical cardiovascular practice has been slowed by several challenges and uncertainties that have been highlighted by the conflicting results of human trials. Most telling has been the revelation that current strategies fall short of achieving sufficient retention and engraftment of cells to meet the ambitious objective of myocardial regeneration. This has sparked novel research into the refinement of cell biology and delivery to overcome these shortcomings. Within this context, molecular imaging has emerged as a valuable tool for providing noninvasive surveillance of cell fate in vivo. Direct and indirect labelling of cells can be coupled with clinically relevant imaging modalities, such as radionuclide single photon emission computed tomography and positron emission tomography, and magnetic resonance imaging, to assess their short- and long-term distributions, along with their viability, proliferation and functional interaction with the host myocardium. This review details the strengths and limitations of the different cell labelling and imaging techniques and their potential application to the clinical realm. We also consider the broader, multifaceted utility of imaging throughout the cell therapy process, providing a discussion of its considerable value during cell delivery and its importance during the evaluation of cardiac outcomes in clinical studies. PMID:21901381

  10. Emerging roles for integrated imaging modalities in cardiovascular cell-based therapeutics: a clinical perspective.

    PubMed

    Psaltis, Peter J; Simari, Robert D; Rodriguez-Porcel, Martin

    2012-01-01

    Despite preclinical promise, the progress of cell-based therapy to clinical cardiovascular practice has been slowed by several challenges and uncertainties that have been highlighted by the conflicting results of human trials. Most telling has been the revelation that current strategies fall short of achieving sufficient retention and engraftment of cells to meet the ambitious objective of myocardial regeneration. This has sparked novel research into the refinement of cell biology and delivery to overcome these shortcomings. Within this context, molecular imaging has emerged as a valuable tool for providing noninvasive surveillance of cell fate in vivo. Direct and indirect labelling of cells can be coupled with clinically relevant imaging modalities, such as radionuclide single photon emission computed tomography and positron emission tomography, and magnetic resonance imaging, to assess their short- and long-term distributions, along with their viability, proliferation and functional interaction with the host myocardium. This review details the strengths and limitations of the different cell labelling and imaging techniques and their potential application to the clinical realm. We also consider the broader, multifaceted utility of imaging throughout the cell therapy process, providing a discussion of its considerable value during cell delivery and its importance during the evaluation of cardiac outcomes in clinical studies.

  11. Three-dimensional imaging of flat natural and cultural heritage objects by a Compton scattering modality

    NASA Astrophysics Data System (ADS)

    Guerrero Prado, Patricio; Nguyen, Mai K.; Dumas, Laurent; Cohen, Serge X.

    2017-01-01

    Characterization and interpretation of flat ancient material objects, such as those found in archaeology, paleoenvironments, paleontology, and cultural heritage, have remained a challenging task to perform by means of conventional x-ray tomography methods due to their anisotropic morphology and flattened geometry. To overcome the limitations of the mentioned methodologies for such samples, an imaging modality based on Compton scattering is proposed in this work. Classical x-ray tomography treats Compton scattering data as noise in the image formation process, while in Compton scattering tomography the conditions are set such that Compton data become the principal image contrasting agent. Under these conditions, we are able, first, to avoid relative rotations between the sample and the imaging setup, and second, to obtain three-dimensional data even when the object is supported by a dense material by exploiting backscattered photons. Mathematically this problem is addressed by means of a conical Radon transform and its inversion. The image formation process and object reconstruction model are presented. The feasibility of this methodology is supported by numerical simulations.

  12. X-ray digital imaging petrography of lunar mare soils: modal analyses of minerals and glasses

    NASA Technical Reports Server (NTRS)

    Taylor, L. A.; Patchen, A.; Taylor, D. H.; Chambers, J. G.; McKay, D. S.

    1996-01-01

    It is essential that accurate modal (i.e., volume) percentages of the various mineral and glass phases in lunar soils be used for addressing and resolving the effects of space weathering upon reflectance spectra, as well as for their calibration such data are also required for evaluating the resource potential of lunar minerals for use at a lunar base. However, these data are largely lacking. Particle-counting information for lunar soils, originally obtained to study formational processes, does not provide these necessary data, including the percentages of minerals locked in multi-phase lithic fragments and fused-soil particles, such as agglutinates. We have developed a technique for modal analyses, sensu stricto, of lunar soils, using digital imaging of X-ray maps obtained with an energy-dispersive spectrometer mounted on an electron microprobe. A suite of nine soils (90 to 150 micrometers size fraction) from the Apollo 11, 12, 15, and 17 mare sites was used for this study. This is the first collection of such modal data on soils from all Apollo mare sites. The abundances of free-mineral fragments in the mare soils are greater for immature and submature soils than for mature soils, largely because of the formation of agglutinitic glass as maturity progresses. In considerations of resource utilization at a lunar base, the best lunar soils to use for mineral beneficiation (i.e., most free-mineral fragments) have maturities near the immature/submature boundary (Is/FeO approximately or = 30), not the mature soils with their complications due to extensive agglutination. The particle data obtained from the nine mare soils confirm the generalizations for lunar soils predicted by L.A. Taylor and D.S. McKay (1992, Lunar Planet Sci. Conf. 23rd, pp. 1411-1412 [Abstract]).

  13. X-ray digital imaging petrography of lunar mare soils: modal analyses of minerals and glasses.

    PubMed

    Taylor, L A; Patchen, A; Taylor, D H; Chambers, J G; McKay, D S

    1996-12-01

    It is essential that accurate modal (i.e., volume) percentages of the various mineral and glass phases in lunar soils be used for addressing and resolving the effects of space weathering upon reflectance spectra, as well as for their calibration such data are also required for evaluating the resource potential of lunar minerals for use at a lunar base. However, these data are largely lacking. Particle-counting information for lunar soils, originally obtained to study formational processes, does not provide these necessary data, including the percentages of minerals locked in multi-phase lithic fragments and fused-soil particles, such as agglutinates. We have developed a technique for modal analyses, sensu stricto, of lunar soils, using digital imaging of X-ray maps obtained with an energy-dispersive spectrometer mounted on an electron microprobe. A suite of nine soils (90 to 150 micrometers size fraction) from the Apollo 11, 12, 15, and 17 mare sites was used for this study. This is the first collection of such modal data on soils from all Apollo mare sites. The abundances of free-mineral fragments in the mare soils are greater for immature and submature soils than for mature soils, largely because of the formation of agglutinitic glass as maturity progresses. In considerations of resource utilization at a lunar base, the best lunar soils to use for mineral beneficiation (i.e., most free-mineral fragments) have maturities near the immature/submature boundary (Is/FeO approximately or = 30), not the mature soils with their complications due to extensive agglutination. The particle data obtained from the nine mare soils confirm the generalizations for lunar soils predicted by L.A. Taylor and D.S. McKay (1992, Lunar Planet Sci. Conf. 23rd, pp. 1411-1412 [Abstract]).

  14. Recent and future evolutions in NeuroSPECT with particular emphasis on the synergistic use and fusion of imaging modalities.

    PubMed

    d'Asseler, Y M; Koole, M; Lemahieu, I; Achten, E; Boon, P; De Deyn, P P; Dierckx, R A

    1997-09-01

    Recent and future evolutions in neuroSPECT apply to radiopharmaceuticals techniques and the synergistic use of different imaging modalities in the work-up of neurological disorders. The introduction of Technetium labelled perfusion tracers, which could pass the intact blood-brain barrier, together with the implementation of the tomographic principle, by making the conventional gamma camera rotating, enabled estimation of regional cerebral blood flow and indirectly of local brain metabolism. In addition at present Thallium-201 and Tc-99m sestaMIBI allow functional detection of viable tumor tissue, without interference from previous surgery or radiotherapy as seen using CT-scan or MRI. In neurology this has led to the recognition of SPECT by the American Academy of Neurology (Therapeutics and technology subcommittee) as an established or promising tool in major neurological disorders such as dementia, stroke and epilepsy, while other domains such as brain oncology are considered investigational. With regard to radiopharmaceuticals, recent evolutions mainly include the development of mostly Iodine-123 labelled receptor ligands, some of which are already commercially available. For instrumentation advances consist e.g. of multidetector systems equipped with fanbeam collimators, attenuation and scatter correction or coincidence detection. Given the present role for nuclear neurology it may be expected that these additional radiopharmaceutical and technical innovations will continue to stimulate the development of SPECT of the brain. The synergistic use of several imaging techniques such as CT, (functional) MRI, source imaging, SPECT and PET represents a multimodal holistic approach to probe cerebral functions for research and clinical purposes. Clinical indications, in which this synergistic use is illustrated include e.g. support of the clinical diagnosis of dementia of the Alzheimer type, presurgical ictal detection of seizure focus, detection of acute ischemia and

  15. Hopc: a Novel Similarity Metric Based on Geometric Structural Properties for Multi-Modal Remote Sensing Image Matching

    NASA Astrophysics Data System (ADS)

    Ye, Yuanxin; Shen, Li

    2016-06-01

    Automatic matching of multi-modal remote sensing images (e.g., optical, LiDAR, SAR and maps) remains a challenging task in remote sensing image analysis due to significant non-linear radiometric differences between these images. This paper addresses this problem and proposes a novel similarity metric for multi-modal matching using geometric structural properties of images. We first extend the phase congruency model with illumination and contrast invariance, and then use the extended model to build a dense descriptor called the Histogram of Orientated Phase Congruency (HOPC) that captures geometric structure or shape features of images. Finally, HOPC is integrated as the similarity metric to detect tie-points between images by designing a fast template matching scheme. This novel metric aims to represent geometric structural similarities between multi-modal remote sensing datasets and is robust against significant non-linear radiometric changes. HOPC has been evaluated with a variety of multi-modal images including optical, LiDAR, SAR and map data. Experimental results show its superiority to the recent state-of-the-art similarity metrics (e.g., NCC, MI, etc.), and demonstrate its improved matching performance.

  16. Dual Optical Modality Endoscopic Imaging of Cancer Development in the Mouse Colon

    PubMed Central

    Keenan, Molly R.; Leung, Sarah J.; Rice, Photini S.; Wall, R. Andrew; Barton, Jennifer K.

    2014-01-01

    Background and Objective We utilize a miniature, dual-modality endoscope that combines fluorescence-based surface magnifying chromoendoscopy (SMC) and optical coherence tomography (OCT) to follow the anatomical changes that occur during adenoma development in the mouse colon. Materials and Methods Twenty-five mice were treated with the carcinogen azoxymethane (AOM) to induce tumor development in the distal colon, or were treated with saline as control, and were imaged over six months. OCT detects adenoma number with high sensitivity and specificity and can measure lesion size. In methylene blue-lavaged colons, SMC detects changes in the colonic crypts. SMC images of control mouse colons exhibit reticulated patterns of crypts of equal size, forming either a dot or honeycomb pattern. Results Images of AOM-treated colons show mild crypt irregularities even in grossly normal tissue. Images of small to medium adenoma exhibit larger crypts, more intense signal, and irregular spacing whereas those of large adenoma have heterogeneous, intense signal and loss of crypt structure. Conclusions The combination of OCT and SMC permits the detection of neoplastic events from the earliest stages of crypt irregularities before gross tissue changes are noted, through to measuring the growth of protruding adenoma. PMID:25449147

  17. A Convergent Functional Architecture of the Insula Emerges Across Imaging Modalities

    PubMed Central

    Kelly, Clare; Toro, Roberto; Di Martino, Adriana; Cox, Christine L.; Bellec, Pierre; Castellanos, F. Xavier; Milham, Michael P.

    2012-01-01

    Empirical evidence increasingly supports the hypothesis that patterns of intrinsic functional connectivity (iFC) are sculpted by a history of evoked coactivation within distinct neuronal networks. This, together with evidence of strong correspondence among the networks defined by iFC and those delineated using a variety of other neuroimaging techniques, suggests a fundamental brain architecture detectable across multiple functional and structural imaging modalities. Here, we leverage this insight to examine the functional organization of the human insula. We parcellated the insula on the basis of three distinct neuroimaging modalities – task-evoked coactivation, intrinsic (i.e., task-independent) functional connectivity, and grey matter structural covariance. Clustering of these three different covariance-based measures revealed a convergent elemental organization of the insula that likely reflects a fundamental brain architecture governing both brain structure and function at multiple spatial scales. While not constrained to be hierarchical, our parcellation revealed a pseudo-hierarchical, multiscale organization that was consistent with previous clustering and meta-analytic studies of the insula. Finally, meta-analytic examination of the cognitive and behavioral domains associated with each of the insular clusters obtained elucidated the broad functional dissociations likely underlying the topography observed. To facilitate future investigations of insula function across healthy and pathological states, the insular parcels obtained here have been made freely available for download via http://fcon_1000.projects.nitrc.org, along with the analytic scripts used to perform the parcellations. PMID:22440648

  18. Diagnostic modalities.

    PubMed

    Elstob, Alison; Gonsalves, Michael; Patel, Uday

    2016-12-01

    The incidental detection of small renal masses on imaging undertaken to evaluate unrelated symptoms or conditions is an increasingly common occurrence. Accurate imaging characterisation is fundamental to determining optimum patient management. The goals of imaging small renal masses include determining whether a lesion is solid or cystic, if there are signs of biological aggressiveness and whether the lesion is likely benign or malignant. The current imaging practices and the evidence supporting the use of different imaging modalities for the characterisation of small renal masses are discussed. CT remains the primary imaging modality and is able to classify most masses into surgical or non-surgical lesions. MRI and contrast enhanced ultrasound are most often employed to problem solve in lesions deemed indeterminate on contrast enhanced CT or for patients in which CECT is contraindicated. Percutaneous biopsy should be considered in lesions that remain indeterminate after initial imaging investigations. Given the central role of imaging in the management of small renal masses, all multidisciplinary team members involved in renal cancer care should have an understanding of the performance of the different imaging modalities.

  19. SU-E-I-53: Variation in Measurements of Breast Skin Thickness Obtained Using Different Imaging Modalities

    SciTech Connect

    Nguyen, U; Kumaraswamy, N; Markey, M

    2014-06-01

    Purpose: To investigate variation in measurements of breast skin thickness obtained using different imaging modalities, including mammography, computed tomography (CT), ultrasound, and magnetic resonance imaging (MRI). Methods: Breast skin thicknesses as measured by mammography, CT, ultrasound, and MRI were compared. Mammographic measurements of skin thickness were obtained from published studies that utilized standard positioning (upright) and compression. CT measurements of skin thickness were obtained from a published study of a prototype breast CT scanner in which the women were in the prone position and the breast was uncompressed. Dermatological ultrasound exams of the breast skin were conducted at our institution, with the subjects in the upright position and the breast uncompressed. Breast skin thickness was calculated from breast MRI exams at our institution, with the patient in the prone position and the breast uncompressed. Results: T tests for independent samples demonstrated significant differences in the mean breast skin thickness as measured by different imaging modalities. Repeated measures ANOVA revealed significant differences in breast skin thickness across different quadrants of the breast for some modalities. Conclusion: The measurement of breast skin thickness is significantly different across different imaging modalities. Differences in the amount of compression and differences in patient positioning are possible reasons why measurements of breast skin thickness vary by modality.

  20. Development of a Macromolecular Dual-Modality MR-Optical Imaging for Sentinel Lymph Node Mapping

    PubMed Central

    Melancon, Marites P.; Wang, Yuetang; Wen, Xiaoxia; Bankson, James A.; Stephens, L. Clifton; Jasser, Samar; Gelovani, Juri G.; Myers, Jeffrey N.; Li, Chun

    2009-01-01

    Objective To evaluate the effectiveness of a dual magnetic resonance-near infrared fluorescence optical imaging agent, poly(L-glutamic acid)-DTPA-Gd-NIR813, for both preoperative and intraoperative visualization and characterization of sentinel lymph nodes (SLN) in mice. Materials and Methods Poly(L-glutamic acid) was conjugated with DTPA-Gd and NIR813 dye to obtain PG-DTPA-Gd-NIR813. To confirm drainage into the SLNs, this agent was injected subcutaneously into the front paw of nude mice followed by isosulfan blue (n = 6). Furthermore, PG-DTPA-Gd-NIR813 was injected subcutaneously at doses of 0.002 mmol Gd/kg (4.8 nmol eq. NIR813) and 0.02 mmol Gd/kg (48 nmol eq. NIR813) (n = 3/dose). To differentiate metastatic from non-metastatic lymph nodes, nude mice bearing human oral squamous cell carcinoma (DM14) were injected intralingually with 0.02 mmol Gd/kg PG-DTPA-Gd-NIR813 (n=3). Pre- and post-contrast images were taken using 4.7T Bruker MRI scanner and Xenogen optical imaging system. The status of lymph nodes resected under the guidance of optical imaging was confirmed by histologic examinations. Results PG-DTPA-Gd-NIR813 co-localized with isosulfan blue, indicating drainage to the SLN. After subcutaneous injection, axiliary and branchial lymph nodes were clearly visualized with both T1-weighted MR and optical imaging within 3 min of contrast injection, even at the lowest dose tested (0.002 mmol Gd/kg). After intralingual injection in tumor-bearing mice, MR imaging identified 4 of the 6 superficial cervical lymph nodes, whereas NIRF optical imaging identified all 6 cervical nodes. The pattern of contrast enhancement of SLN visualized in MR images showed a characteristic ring-shaped appearance with a central filling defect, possibly resulting from nodal infiltration of metastatic lesions. Histopathologic examination of the SLNs resected under NIRF imaging guidance revealed micrometastases in all 6 SLNs identified by NIRF imaging. Conclusion The dual modality imaging

  1. Biodegradable microparticles with surface dimples as a bi-modal imaging contrast agent.

    PubMed

    Kim, Mi Ri; Lim, Yong Taik; Cho, Kuk Young

    2013-03-12

    Fabrication of physically engineered colloids and their application to the biological fields is emerging importance because of their potential to provide an enhanced performance without altering the chemical properties of biomaterials used. A facile approach is reported to fabricate sub-10-μm-sized PLGA microparticle with small dimples covering the surface by droplet imprinting. Optical and magnetic resonance bioimaging agents are easily co-encapsulated inside the microparticles to obtain a bi-modal imaging agent. Cell internalization efficacy of dimpled particles in DC 2.4 cell is enhanced compared with conventional smooth round-shaped colloids. Our result indicates that morphology-controlled microparticles show promise as a cell labeling with improved cell interaction.

  2. Tomographic imaging of incipient dental-caries using optical coherence tomography and comparison with various modalities

    NASA Astrophysics Data System (ADS)

    Na, Jihoon; Baek, Jae Ho; Ryu, Seon Young; Lee, Changsu; Lee, Byeong Ha

    2009-07-01

    We present the optical coherence tomography (OCT) made to investigate the early dental caries in human teeth and compare its results with those taken by conventional imaging modalities including light illuminating examination (LIE), digital intra-oral radiography (DIOR), and electron probe micro analyzer (EPMA). Morphological features and caries-involved areas of the dental structure were mainly investigated by LIE, DIOR, and OCT to study the infection of the caries lesion in pits and fissures. The biochemical information acquired with EPMA and the morphological features taken with OCT in the early stage of caries were compared and analyzed to present an objective and practical index for the degree of caries. The experimental results allow us to conclude that OCT could be used to provide quantitative analysis of caries based on the reflectivity difference in the specimen.

  3. Submitral aneurysm and the new imaging modalities: Will magnetic resonance imaging be necessary?

    PubMed

    Morais, Humberto; Manuel, Valdano; Costa, João Carlos

    2016-10-01

    Submitral aneurysm is a rare cardiac malformation commonly reported in young adult African ancestry. Transthoracic echocardiogram is a gold standard test for diagnosis. Magnetic resonance imaging provides detailed anatomic and functional information of the heart. We present a case of a large bilobed submitral aneurysm in-witch the magnetic resonance imaging confirmed the same findings of the transthoracic echocardiography and in addiction also showed a parietal thrombus.

  4. Multi-modal hard x-ray imaging with a laboratory source using selective reflection from a mirror.

    PubMed

    Pelliccia, Daniele; Paganin, David M

    2014-04-01

    Multi-modal hard x-ray imaging sensitive to absorption, refraction, phase and scattering contrast is demonstrated using a simple setup implemented with a laboratory source. The method is based on selective reflection at the edge of a mirror, aligned to partially reflect a pencil x-ray beam after its interaction with a sample. Quantitative scattering contrast from a test sample is experimentally demonstrated using this method. Multi-modal imaging of a house fly (Musca domestica) is shown as proof of principle of the technique for biological samples.

  5. Multi-Modality Phantom Development

    SciTech Connect

    Huber, Jennifer S.; Peng, Qiyu; Moses, William W.

    2009-03-20

    Multi-modality imaging has an increasing role in the diagnosis and treatment of a large number of diseases, particularly if both functional and anatomical information are acquired and accurately co-registered. Hence, there is a resulting need for multi modality phantoms in order to validate image co-registration and calibrate the imaging systems. We present our PET-ultrasound phantom development, including PET and ultrasound images of a simple prostate phantom. We use agar and gelatin mixed with a radioactive solution. We also present our development of custom multi-modality phantoms that are compatible with PET, transrectal ultrasound (TRUS), MRI and CT imaging. We describe both our selection of tissue mimicking materials and phantom construction procedures. These custom PET-TRUS-CT-MRI prostate phantoms use agargelatin radioactive mixtures with additional contrast agents and preservatives. We show multi-modality images of these custom prostate phantoms, as well as discuss phantom construction alternatives. Although we are currently focused on prostate imaging, this phantom development is applicable to many multi-modality imaging applications.

  6. Experimental validation of a high-resolution diffuse optical imaging modality: photomagnetic imaging

    PubMed Central

    Nouizi, Farouk; Luk, Alex; Thayer, Dave; Lin, Yuting; Ha, Seunghoon; Gulsen, Gultekin

    2016-01-01

    Abstract. We present experimental results that validate our imaging technique termed photomagnetic imaging (PMI). PMI illuminates the medium under investigation with a near-infrared light and measures the induced temperature increase using magnetic resonance imaging. A multiphysics solver combining light and heat propagation is used to model spatiotemporal distribution of temperature increase. Furthermore, a dedicated PMI reconstruction algorithm has been developed to reveal high-resolution optical absorption maps from temperature measurements. Being able to perform measurements at any point within the medium, PMI overcomes the limitations of conventional diffuse optical imaging. We present experimental results obtained on agarose phantoms mimicking biological tissue with inclusions having either different sizes or absorption contrasts, located at various depths. The reconstructed images show that PMI can successfully resolve these inclusions with high resolution and recover their absorption coefficient with high-quantitative accuracy. Even a 1-mm inclusion located 6-mm deep is recovered successfully and its absorption coefficient is underestimated by only 32%. The improved PMI system presented here successfully operates under the maximum skin exposure limits defined by the American National Standards Institute, which opens up the exciting possibility of its future clinical use for diagnostic purposes. PMID:26790644

  7. Experimental validation of a high-resolution diffuse optical imaging modality: photomagnetic imaging

    NASA Astrophysics Data System (ADS)

    Nouizi, Farouk; Luk, Alex; Thayer, Dave; Lin, Yuting; Ha, Seunghoon; Gulsen, Gultekin

    2016-01-01

    We present experimental results that validate our imaging technique termed photomagnetic imaging (PMI). PMI illuminates the medium under investigation with a near-infrared light and measures the induced temperature increase using magnetic resonance imaging. A multiphysics solver combining light and heat propagation is used to model spatiotemporal distribution of temperature increase. Furthermore, a dedicated PMI reconstruction algorithm has been developed to reveal high-resolution optical absorption maps from temperature measurements. Being able to perform measurements at any point within the medium, PMI overcomes the limitations of conventional diffuse optical imaging. We present experimental results obtained on agarose phantoms mimicking biological tissue with inclusions having either different sizes or absorption contrasts, located at various depths. The reconstructed images show that PMI can successfully resolve these inclusions with high resolution and recover their absorption coefficient with high-quantitative accuracy. Even a 1-mm inclusion located 6-mm deep is recovered successfully and its absorption coefficient is underestimated by only 32%. The improved PMI system presented here successfully operates under the maximum skin exposure limits defined by the American National Standards Institute, which opens up the exciting possibility of its future clinical use for diagnostic purposes.

  8. Stereoscopic high-speed imaging using additive colors

    PubMed Central

    Sankin, Georgy N.; Piech, David; Zhong, Pei

    2012-01-01

    An experimental system for digital stereoscopic imaging produced by using a high-speed color camera is described. Two bright-field image projections of a three-dimensional object are captured utilizing additive-color backlighting (blue and red). The two images are simultaneously combined on a two-dimensional image sensor using a set of dichromatic mirrors, and stored for off-line separation of each projection. This method has been demonstrated in analyzing cavitation bubble dynamics near boundaries. This technique may be useful for flow visualization and in machine vision applications. PMID:22559533

  9. Imaging modalities for the in vivo surveillance of mesenchymal stromal cells.

    PubMed

    Hossain, Mohammad Ayaz; Chowdhury, Tina; Bagul, Atul

    2015-11-01

    Bone marrow stromal cells exist as mesenchymal stromal cells (MSCs) and have the capacity to differentiate into multiple tissue types when subjected to appropriate culture conditions. This property of MSCs creates therapeutic opportunities in regenerative medicine for the treatment of damage to neural, cardiac and musculoskeletal tissues or acute kidney injury. The prerequisite for successful cell therapy is delivery of cells to the target tissue. Assessment of therapeutic outcomes utilize traditional methods to examine cell function of MSC populations involving routine biochemical or histological analysis for cell proliferation, protein synthesis and gene expression. However, these methods do not provide sufficient spatial and temporal information. In vivo surveillance of MSC migration to the site of interest can be performed through a variety of imaging modalities such as the use of radiolabelling, fluc protein expression bioluminescence imaging and paramagnetic nanoparticle magnetic resonance imaging. This review will outline the current methods of in vivo surveillance of exogenously administered MSCs in regenerative medicine while addressing potential technological developments. Furthermore, nanoparticles and microparticles for cellular labelling have shown that migration of MSCs can be spatially and temporally monitored. In vivo surveillance therefore permits time-stratified assessment in animal models without disruption of the target organ. In vivo tracking of MSCs is non-invasive, repeatable and non-toxic. Despite the excitement that nanoparticles for tracking MSCs offer, delivery methods are difficult because of the challenges with imaging three-dimensional systems. The current advances and growth in MSC research, is likely to provide a wealth of evidence overcoming these issues.

  10. Dual modality imaging of a novel rat model of ovarian carcinogenesis

    NASA Astrophysics Data System (ADS)

    Kanter, Elizabeth; Walker, Ross; Marion, Sam; Brewer, Molly A.; Hoyer, Patricia B.; Barton, Jennifer K.

    2006-07-01

    Ovarian cancer is the fifth leading cause of cancer death in women, in part because of the limited knowledge about early stage disease. We develop a novel rat model of ovarian cancer and perform a pilot study to examine the harvested ovaries with complementary optical imaging modalities. Rats are exposed to repeated daily dosing (20 days) with 4-vinylcyclohexene diepoxide (VCD) to cause early ovarian failure (model for postmenopause), and ovaries are directly exposed to 7,12-dimethylbenz(a)anthracene (DMBA) to cause abnormal ovarian proliferation and neoplasia. Harvested ovaries are examined with optical coherence tomography (OCT) and light-induced fluorescence (LIF) at one, three, and five months post-DMBA treatment. VCD causes complete ovarian follicle depletion within 8 months after onset of dosing. DMBA induces abnormal size, cysts, and neoplastic changes. OCT successfully visualizes normal and abnormal structures (e.g., cysts, bursa, follicular remnant degeneration) and the LIF spectra show statistically significant changes in the ratio of average emission intensity at 390:450 nm between VCD-treated ovaries and both normal cycling and neoplastic DMBA-treated ovaries. Overall, this pilot study demonstrates the feasibility of both the novel animal model for ovarian cancer and the ability of optical imaging techniques to visualize ovarian function and health.

  11. Imaging of EGFR and EGFR Tyrosine Kinase Overexpression in Tumors by Nuclear Medicine Modalities

    PubMed Central

    Mishani, Eyal; Abourbeh, Galith; Eiblmaier, Martin; Anderson, Carolyn J

    2008-01-01

    Protein tyrosine kinases (PTKs) play a pivotal role in signal transduction pathways and in the development and maintenance of various cancers. They are involved in multiple processes such as transcription, cell cycle progression, proliferation, angiogenesis and inhibition of apoptosis. Among the PTKs, the EGFR is one of the most widely studied and has emerged as a promising key target for the treatment of cancer. Indeed, several drugs directed at this receptor are FDA-approved and many others are at various stages of development. However, thus far, the therapeutic outcome of EGFR-targeted therapy is suboptimal and needs to be refined. Quantitative PET molecular imaging coupled with selective labelled biomarkers may facilitate in vivo EGFR-targeted drug efficacy by noninvasively assessing the expression of EGFR in tumor, guiding dose and regime by measuring target drug binding and receptor occupancy as well as potentially detecting the existence of a primary or secondary mutation leading to either drug interaction or failure of EGFR recognition by the drug. This review describes the attempts to develop labelled EGFR molecular imaging agents that are based either on low molecular weight tyrosine kinase inhibitors or monoclonal antibodies directed to the extracellular binding domain of the receptor to be used in nuclear medicine modalities. PMID:18991714

  12. Application prospective of nanoprobes with MRI and FI dual-modality imaging on breast cancer stem cells in tumor.

    PubMed

    Chen, Hetao; Wang, Yu; Wang, Tong; Shi, Dongxing; Sun, Zengrong; Xia, Chunhui; Wang, Baiqi

    2016-06-23

    Breast cancer (BC) is a serious disease to threat lives of women. Numerous studies have proved that BC originates from cancer stem cells (CSCs). But at present, no one approach can quickly and simply identify breast cancer stem cells (BCSCs) in solid tumor. Nanotechnology is probably able to realize this goal. But in study process, scientists find it seems that nanomaterials with one modality, such as magnetic resonance imaging (MRI) or fluorescence imaging (FI), have their own advantages and drawbacks. They cannot meet practical requirements in clinic. The nanoprobe combined MRI with FI modality is a promising tool to accurately detect desired cells with low amount in tissue. In this work, we briefly describe the MRI and FI development history, analyze advantages and disadvantages of nanomaterials with single modality in cancer cell detection. Then the application development of nanomaterials with dual-modality in cancer field is discussed. Finally, the obstacles and prospective of dual-modal nanoparticles in detection field of BCSCs are also pointed out in order to speed up clinical applications of nanoprobes.

  13. A Dual-Modality System for Both Multi-Color Ultrasound-Switchable Fluorescence and Ultrasound Imaging

    PubMed Central

    Kandukuri, Jayanth; Yu, Shuai; Cheng, Bingbing; Bandi, Venugopal; D’Souza, Francis; Nguyen, Kytai T.; Hong, Yi; Yuan, Baohong

    2017-01-01

    Simultaneous imaging of multiple targets (SIMT) in opaque biological tissues is an important goal for molecular imaging in the future. Multi-color fluorescence imaging in deep tissues is a promising technology to reach this goal. In this work, we developed a dual-modality imaging system by combining our recently developed ultrasound-switchable fluorescence (USF) imaging technology with the conventional ultrasound (US) B-mode imaging. This dual-modality system can simultaneously image tissue acoustic structure information and multi-color fluorophores in centimeter-deep tissue with comparable spatial resolutions. To conduct USF imaging on the same plane (i.e., x-z plane) as US imaging, we adopted two 90°-crossed ultrasound transducers with an overlapped focal region, while the US transducer (the third one) was positioned at the center of these two USF transducers. Thus, the axial resolution of USF is close to the lateral resolution, which allows a point-by-point USF scanning on the same plane as the US imaging. Both multi-color USF and ultrasound imaging of a tissue phantom were demonstrated. PMID:28165390

  14. Intrinsically germanium-69-labeled iron oxide nanoparticles: synthesis and in-vivo dual-modality PET/MR imaging.

    PubMed

    Chakravarty, Rubel; Valdovinos, Hector F; Chen, Feng; Lewis, Christina M; Ellison, Paul A; Luo, Haiming; Meyerand, M Elizabeth; Nickles, Robert J; Cai, Weibo

    2014-08-13

    Intrinsically germanium-69-labeled super-paramagnetic iron oxide nanoparticles are synthesized via a newly developed, fast and highly specific chelator-free approach. The biodistribution pattern and the feasibility of (69) Ge-SPION@PEG for in vivo dual-modality positron emission tomography/magnetic resonance (PET/MR) imaging and lymph-node mapping are investigated, which represents the first example of the successful utilization of a (69) Ge-based agent for PET/MR imaging.

  15. Indocyanine Green Loaded Reduced Graphene Oxide for In Vivo Photoacoustic/Fluorescence Dual-Modality Tumor Imaging.

    PubMed

    Chen, Jingqin; Liu, Chengbo; Zeng, Guang; You, Yujia; Wang, Huina; Gong, Xiaojing; Zheng, Rongqin; Kim, Jeesu; Kim, Chulhong; Song, Liang

    2016-12-01

    Multimodality imaging based on multifunctional nanocomposites holds great promise to fundamentally augment the capability of biomedical imaging. Specifically, photoacoustic and fluorescence dual-modality imaging is gaining much interest because of their non-invasiveness and the complementary nature of the two modalities in terms of imaging resolution, depth, sensitivity, and speed. Herein, using a green and facile method, we synthesize indocyanine green (ICG) loaded, polyethylene glycol (PEG)ylated, reduced nano-graphene oxide nanocomposite (rNGO-PEG/ICG) as a new type of fluorescence and photoacoustic dual-modality imaging contrast. The nanocomposite is shown to have minimal toxicity and excellent photoacoustic/fluorescence signals both in vitro and in vivo. Compared with free ICG, the nanocomposite is demonstrated to possess greater stability, longer blood circulation time, and superior passive tumor targeting capability. In vivo study shows that the circulation time of rNGO-PEG/ICG in the mouse body can sustain up to 6 h upon intravenous injection; while after 1 day, no obvious accumulation of rNGO-PEG/ICG is found in any major organs except the tumor regions. The demonstrated high fluorescence/photoacoustic dual contrasts, together with its low toxicity and excellent circulation life time, suggest that the synthesized rNGO-PEG/ICG can be a promising candidate for further translational studies on both the early diagnosis and image-guided therapy/surgery of cancer.

  16. Automated segmentation of corticospinal tract in diffusion tensor images via multi-modality multi-atlas fusion

    NASA Astrophysics Data System (ADS)

    Tang, Xiaoying; Mori, Susumu; Miller, Michael I.

    2014-03-01

    In this paper, we propose a method to automatically segment the corticospinal tract (CST) in diffusion tensor images (DTIs) by incorporating the anatomical features from multi-modality images generated in DTI using multiple DTI atlases. The to-be-segmented test subject, and each atlas, is comprised of images with different modalities - the mean diffusivity, the fractional anisotropy, and the images representing the three elements of the primary eigenvector. Each atlas had a paired image containing the manually delineated segmentations of the three regions of interest - the left and right CST and the background surrounding the CST. We solve the problem via maximum a posteriori estimation using generative models. Each modality image is modeled as a conditional Gaussian mixture random field, conditioned on the atlas-label pair and the local change of coordinates for each label. The expectation-maximization algorithm is used to alternatively estimate the local optimal diffeomorphisms for each label and the maximizing segmentations. The algorithm is evaluated on six subjects with a wide range of pathology. We compare the proposed method with two state-of-the-art multi-atlas based label fusion methods, against which the method displayed a high level of accuracy.

  17. Indocyanine Green Loaded Reduced Graphene Oxide for In Vivo Photoacoustic/Fluorescence Dual-Modality Tumor Imaging

    NASA Astrophysics Data System (ADS)

    Chen, Jingqin; Liu, Chengbo; Zeng, Guang; You, Yujia; Wang, Huina; Gong, Xiaojing; Zheng, Rongqin; Kim, Jeesu; Kim, Chulhong; Song, Liang

    2016-02-01

    Multimodality imaging based on multifunctional nanocomposites holds great promise to fundamentally augment the capability of biomedical imaging. Specifically, photoacoustic and fluorescence dual-modality imaging is gaining much interest because of their non-invasiveness and the complementary nature of the two modalities in terms of imaging resolution, depth, sensitivity, and speed. Herein, using a green and facile method, we synthesize indocyanine green (ICG) loaded, polyethylene glycol (PEG)ylated, reduced nano-graphene oxide nanocomposite (rNGO-PEG/ICG) as a new type of fluorescence and photoacoustic dual-modality imaging contrast. The nanocomposite is shown to have minimal toxicity and excellent photoacoustic/fluorescence signals both in vitro and in vivo. Compared with free ICG, the nanocomposite is demonstrated to possess greater stability, longer blood circulation time, and superior passive tumor targeting capability. In vivo study shows that the circulation time of rNGO-PEG/ICG in the mouse body can sustain up to 6 h upon intravenous injection; while after 1 day, no obvious accumulation of rNGO-PEG/ICG is found in any major organs except the tumor regions. The demonstrated high fluorescence/photoacoustic dual contrasts, together with its low toxicity and excellent circulation life time, suggest that the synthesized rNGO-PEG/ICG can be a promising candidate for further translational studies on both the early diagnosis and image-guided therapy/surgery of cancer.

  18. Three modality image registration of brain SPECT/CT and MR images for quantitative analysis of dopamine transporter imaging

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Yuzuho; Takeda, Yuta; Hara, Takeshi; Zhou, Xiangrong; Matsusako, Masaki; Tanaka, Yuki; Hosoya, Kazuhiko; Nihei, Tsutomu; Katafuchi, Tetsuro; Fujita, Hiroshi

    2016-03-01

    Important features in Parkinson's disease (PD) are degenerations and losses of dopamine neurons in corpus striatum. 123I-FP-CIT can visualize activities of the dopamine neurons. The activity radio of background to corpus striatum is used for diagnosis of PD and Dementia with Lewy Bodies (DLB). The specific activity can be observed in the corpus striatum on SPECT images, but the location and the shape of the corpus striatum on SPECT images only are often lost because of the low uptake. In contrast, MR images can visualize the locations of the corpus striatum. The purpose of this study was to realize a quantitative image analysis for the SPECT images by using image registration technique with brain MR images that can determine the region of corpus striatum. In this study, the image fusion technique was used to fuse SPECT and MR images by intervening CT image taken by SPECT/CT. The mutual information (MI) for image registration between CT and MR images was used for the registration. Six SPECT/CT and four MR scans of phantom materials are taken by changing the direction. As the results of the image registrations, 16 of 24 combinations were registered within 1.3mm. By applying the approach to 32 clinical SPECT/CT and MR cases, all of the cases were registered within 0.86mm. In conclusions, our registration method has a potential in superimposing MR images on SPECT images.

  19. Lymph node metastasis in patients with gastric cancer: a multi-modality, morphologic and functional imaging study

    PubMed Central

    Zhong, Jinman; Zhao, Weiwei; Ren, Fang; Qi, Shun; Wang, Xifu; Lv, Tianchu; Su, Zhanliang; Yin, Hong; Ren, Jing; Huan, Yi

    2016-01-01

    The aim of the study was to investigate the value of computed tomography (CT), magnetic resonance imaging (MRI) and diffusion weighted imaging (DWI) for diagnosing lymph nodes metastasis before treatment in gastric cancer. Eighty-two patients with proven gastric cancer underwent CT, morphological MRI (T2WI) and DWI examinations. Two radiologists independently assessed these images for the presence of lymph nodes involvement. Pathologic findings were considered as “gold standard”. Independent samples t-test was used for the comparisons of short diameters and ADC values between the positive lymph nodes and the negative lymph nodes. Diagnostic accuracy of these three imaging modalities was evaluated by area under the receiver operating characteristics (ROC) curve (AUC). The ADC value of the positive lymph nodes was (1.15 ± 0.01) × 10-3 mm2/s, which was significantly lower than that of the negative lymph nodes (1.48 ± 0.01) × 10-3 mm2/s (t = 18.70, P < 0.0001). The short diameter of the positive lymph nodes (1.54 ± 0.38 cm) was significantly greater than that of the negative lymph nodes (0.95 ± 0.12 mm) (t = 19.03, P < 0.001). The AUC for all imaging modalities combined (0.893) was significantly larger than that for each imaging modality alone (P < 0.05), and the AUC of DWI (0.797) was significantly larger than (P < 0.05) that of morphological MRI (0.733). There was no statistically significant difference between the AUCs of CT and morphological MRI (P = 0.462). In conclusion, CT, MRI and DWI combined present significantly higher accuracy than each imaging modality alone in the detection of lymph nodes involvement. PMID:28078030

  20. TU-AB-BRA-06: Texture Feature Reproducibility Between PET/CT and PET/MR Imaging Modalities

    SciTech Connect

    Galavis, P; Friedman, K; Chandarana, H; Jackson, K

    2015-06-15

    Purpose: Radiomics involves the extraction of texture features from different imaging modalities with the purpose of developing models to predict patient treatment outcomes. The purpose of this study is to investigate texture feature reproducibility across [18F]FDG PET/CT and [18F]FDG PET/MR imaging in patients with primary malignancies. Methods: Twenty five prospective patients with solid tumors underwent clinical [18F]FDG PET/CT scan followed by [18F]FDG PET/MR scans. In all patients the lesions were identified using nuclear medicine reports. The images were co-registered and segmented using an in-house auto-segmentation method. Fifty features, based on the intensity histogram, second and high order matrices, were extracted from the segmented regions from both image data sets. One-way random-effects ANOVA model of the intra-class correlation coefficient (ICC) was used to establish texture feature correlations between both data sets. Results: Fifty features were classified based on their ICC values, which were found in the range from 0.1 to 0.86, in three categories: high, intermediate, and low. Ten features extracted from second and high-order matrices showed large ICC ≥ 0.70. Seventeen features presented intermediate 0.5 ≤ ICC ≤ 0.65 and the remaining twenty three presented low ICC ≤ 0.45. Conclusion: Features with large ICC values could be reliable candidates for quantification as they lead to similar results from both imaging modalities. Features with small ICC indicates a lack of correlation. Therefore, the use of these features as a quantitative measure will lead to different assessments of the same lesion depending on the imaging modality from where they are extracted. This study shows the importance of the need for further investigation and standardization of features across multiple imaging modalities.

  1. Does Breast Magnetic Resonance Imaging Combined With Conventional Imaging Modalities Decrease the Rates of Surgical Margin Involvement and Reoperation?: A Case-Control Comparative Analysis.

    PubMed

    Lai, Hung-Wen; Chen, Chih-Jung; Lin, Ying-Jen; Chen, Shu-Ling; Wu, Hwa-Koon; Wu, Yu-Ting; Kuo, Shou-Jen; Chen, Shou-Tung; Chen, Dar-Ren

    2016-05-01

    The objective of this study was to assess whether preoperative breast magnetic resonance imaging (MRI) combined with conventional breast imaging techniques decreases the rates of margin involvement and reexcision.Data on patients who underwent surgery for primary operable breast cancer were obtained from the Changhua Christian Hospital (CCH) breast cancer database. The rate of surgical margin involvement and the rate of reoperation were compared between patients who underwent conventional breast imaging modalities (Group A: mammography and sonography) and those who received breast MRI in addition to conventional imaging (Group B: mammography, sonography, and MRI).A total of 1468 patients were enrolled in this study. Among the 733 patients in Group A, 377 (51.4%) received breast-conserving surgery (BCS) and 356 (48.6%) received mastectomy. Among the 735 patients in Group B, 348 (47.3%) received BCS and 387 (52.7%) received mastectomy. There were no significant differences in operative method between patients who received conventional imaging alone and those that received MRI and conventional imaging (P = 0.13). The rate of detection of pathological multifocal/multicentric breast cancer was markedly higher in patients who received preoperative MRI than in those who underwent conventional imaging alone (14.3% vs 8.6%, P < 0.01). The overall rate of surgical margin involvement was significantly lower in patients who received MRI (5.0%) than in those who received conventional imaging alone (9.0%) (P < 0.01). However, a significant reduction in rate of surgical margin positivity was only observed in patients who received BCS (Group A, 14.6%; Group B, 6.6%, P < 0.01). The overall BCS reoperation rates were 11.7% in the conventional imaging group and 3.2% in the combined MRI group (P < 0.01). There were no significant differences in rate of residual cancer in specimens obtained during reoperation between the 2 preoperative imaging groups (Group A, 50

  2. Multi-modality imaging of tumor phenotype and response to therapy

    NASA Astrophysics Data System (ADS)

    Nyflot, Matthew J.

    2011-12-01

    Imaging and radiation oncology have historically been closely linked. However, the vast majority of techniques used in the clinic involve anatomical imaging. Biological imaging offers the potential for innovation in the areas of cancer diagnosis and staging, radiotherapy target definition, and treatment response assessment. Some relevant imaging techniques are FDG PET (for imaging cellular metabolism), FLT PET (proliferation), CuATSM PET (hypoxia), and contrast-enhanced CT (vasculature and perfusion). Here, a technique for quantitative spatial correlation of tumor phenotype is presented for FDG PET, FLT PET, and CuATSM PET images. Additionally, multimodality imaging of treatment response with FLT PET, CuATSM, and dynamic contrast-enhanced CT is presented, in a trial of patients receiving an antiangiogenic agent (Avastin) combined with cisplatin and radiotherapy. Results are also presented for translational applications in animal models, including quantitative assessment of proliferative response to cetuximab with FLT PET and quantification of vascular volume with a blood-pool contrast agent (Fenestra). These techniques have clear applications to radiobiological research and optimized treatment strategies, and may eventually be used for personalized therapy for patients.

  3. Multi-structure segmentation of multi-modal brain images using artificial neural networks

    NASA Astrophysics Data System (ADS)

    Kim, Eun Young; Johnson, Hans

    2010-03-01

    A method for simultaneous segmentation of multiple anatomical brain structures from multi-modal MR images has been developed. An artificial neural network (ANN) was trained from a set of feature vectors created by a combination of high-resolution registration methods, atlas based spatial probability distributions, and a training set of 16 expert traced data sets. A set of feature vectors were adapted to increase performance of ANN segmentation; 1) a modified spatial location for structural symmetry of human brain, 2) neighbors along the priors descent for directional consistency, and 3) candidate vectors based on the priors for the segmentation of multiple structures. The trained neural network was then applied to 8 data sets, and the results were compared with expertly traced structures for validation purposes. Comparing several reliability metrics, including a relative overlap, similarity index, and intraclass correlation of the ANN generated segmentations to a manual trace are similar or higher to those measures previously developed methods. The ANN provides a level of consistency between subjects and time efficiency comparing human labor that allows it to be used for very large studies.

  4. Dual-Modal Magnetic Resonance/Fluorescent Zinc Probes for Pancreatic β-Cell Mass Imaging

    PubMed Central

    Stasiuk, Graeme J; Minuzzi, Florencia; Sae-Heng, Myra; Rivas, Charlotte; Juretschke, Hans-Paul; Piemonti, Lorenzo; Allegrini, Peter R; Laurent, Didier; Duckworth, Andrew R; Beeby, Andrew; Rutter, Guy A; Long, Nicholas J

    2015-01-01

    Despite the contribution of changes in pancreatic β-cell mass to the development of all forms of diabetes mellitus, few robust approaches currently exist to monitor these changes prospectively in vivo. Although magnetic-resonance imaging (MRI) provides a potentially useful technique, targeting MRI-active probes to the β cell has proved challenging. Zinc ions are highly concentrated in the secretory granule, but they are relatively less abundant in the exocrine pancreas and in other tissues. We have therefore developed functional dual-modal probes based on transition-metal chelates capable of binding zinc. The first of these, Gd⋅1, binds ZnII directly by means of an amidoquinoline moiety (AQA), thus causing a large ratiometric Stokes shift in the fluorescence from λem=410 to 500 nm with an increase in relaxivity from r1=4.2 up to 4.9 mM−1 s−1. The probe is efficiently accumulated into secretory granules in β-cell-derived lines and isolated islets, but more poorly by non-endocrine cells, and leads to a reduction in T1 in human islets. In vivo murine studies of Gd⋅1 have shown accumulation of the probe in the pancreas with increased signal intensity over 140 minutes. PMID:25736590

  5. Role of Artificial Intelligence Techniques (Automatic Classifiers) in Molecular Imaging Modalities in Neurodegenerative Diseases.

    PubMed

    Cascianelli, Silvia; Scialpi, Michele; Amici, Serena; Forini, Nevio; Minestrini, Matteo; Fravolini, Mario Luca; Sinzinger, Helmut; Schillaci, Orazio; Palumbo, Barbara

    2017-01-01

    Artificial Intelligence (AI) is a very active Computer Science research field aiming to develop systems that mimic human intelligence and is helpful in many human activities, including Medicine. In this review we presented some examples of the exploiting of AI techniques, in particular automatic classifiers such as Artificial Neural Network (ANN), Support Vector Machine (SVM), Classification Tree (ClT) and ensemble methods like Random Forest (RF), able to analyze findings obtained by positron emission tomography (PET) or single-photon emission tomography (SPECT) scans of patients with Neurodegenerative Diseases, in particular Alzheimer's Disease. We also focused our attention on techniques applied in order to preprocess data and reduce their dimensionality via feature selection or projection in a more representative domain (Principal Component Analysis - PCA - or Partial Least Squares - PLS - are examples of such methods); this is a crucial step while dealing with medical data, since it is necessary to compress patient information and retain only the most useful in order to discriminate subjects into normal and pathological classes. Main literature papers on the application of these techniques to classify patients with neurodegenerative disease extracting data from molecular imaging modalities are reported, showing that the increasing development of computer aided diagnosis systems is very promising to contribute to the diagnostic process.

  6. Methylene blue microbubbles as a model dual-modality contrast agent for ultrasound and activatable photoacoustic imaging.

    PubMed

    Jeon, Mansik; Song, Wentao; Huynh, Elizabeth; Kim, Jungho; Kim, Jeesu; Helfield, Brandon L; Leung, Ben Y C; Goertz, David E; Zheng, Gang; Oh, Jungtaek; Lovell, Jonathan F; Kim, Chulhong

    2014-01-01

    Ultrasound and photoacoustic imaging are highly complementary modalities since both use ultrasonic detection for operation. Increasingly, photoacoustic and ultrasound have been integrated in terms of hardware instrumentation. To generate a broadly accessible dual-modality contrast agent, we generated microbubbles (a standard ultrasound contrast agent) in a solution of methylene blue (a standard photoacoustic dye). This MB2 solution was formed effectively and was optimized as a dual-modality contrast solution. As microbubble concentration increased (with methylene blue concentration constant), photoacoustic signal was attenuated in the MB2 solution. When methylene blue concentration increased (with microbubble concentration held constant), no ultrasonic interference was observed. Using an MB2 solution that strongly attenuated all photoacoustic signal, high powered ultrasound could be used to burst the microbubbles and dramatically enhance photoacoustic contrast (>800-fold increase), providing a new method for spatiotemporal control of photoacoustic signal generation.

  7. Methylene blue microbubbles as a model dual-modality contrast agent for ultrasound and activatable photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Jeon, Mansik; Song, Wentao; Huynh, Elizabeth; Kim, Jungho; Kim, Jeesu; Helfield, Brandon L.; Leung, Ben Y. C.; Goertz, David E.; Zheng, Gang; Oh, Jungtaek; Lovell, Jonathan F.; Kim, Chulhong

    2014-01-01

    Ultrasound and photoacoustic imaging are highly complementary modalities since both use ultrasonic detection for operation. Increasingly, photoacoustic and ultrasound have been integrated in terms of hardware instrumentation. To generate a broadly accessible dual-modality contrast agent, we generated microbubbles (a standard ultrasound contrast agent) in a solution of methylene blue (a standard photoacoustic dye). This MB2 solution was formed effectively and was optimized as a dual-modality contrast solution. As microbubble concentration increased (with methylene blue concentration constant), photoacoustic signal was attenuated in the MB2 solution. When methylene blue concentration increased (with microbubble concentration held constant), no ultrasonic interference was observed. Using an MB2 solution that strongly attenuated all photoacoustic signal, high powered ultrasound could be used to burst the microbubbles and dramatically enhance photoacoustic contrast (>800-fold increase), providing a new method for spatiotemporal control of photoacoustic signal generation.

  8. A practical algorithmic approach to the diagnosis and management of solitary pulmonary nodules: part 1: radiologic characteristics and imaging modalities.

    PubMed

    Patel, Vishal K; Naik, Sagar K; Naidich, David P; Travis, William D; Weingarten, Jeremy A; Lazzaro, Richard; Gutterman, David D; Wentowski, Catherine; Grosu, Horiana B; Raoof, Suhail

    2013-03-01

    The solitary pulmonary nodule (SPN) is frequently encountered on chest imaging and poses an important diagnostic challenge to clinicians. The differential diagnosis is broad, ranging from benign granulomata and infectious processes to malignancy. Important concepts in the evaluation of SPNs include the definition, morphologic characteristics via appropriate imaging modalities, and the calculation of pretest probability of malignancy. Morphologic differentiation of SPN into solid or subsolid types is important in the choice of follow-up and further management. In this first part of a two-part series, we describe the morphologic characteristics and various imaging modalities available to further characterize SPN. In Part 2, we will describe the determination of pretest probability of malignancy and an algorithmic approach to the diagnosis of SPN.

  9. Imaging Modalities for Assessment of Treatment Response to Nonsurgical Hepatocellular Carcinoma Therapy: Contrast-Enhanced US, CT, and MRI.

    PubMed

    Minami, Yasunori; Kudo, Masatoshi

    2015-03-01

    Tumor response and time to progression have been considered pivotal for surrogate assessment of treatment efficacy for patients with hepatocellular carcinoma (HCC). Recent advancements in imaging modalities such as contrast-enhanced ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) are playing an important role in assessing the therapeutic effects of HCC treatments. According to some HCC clinical guidelines, post-therapeutic evaluation of HCC patients is based exclusively on contrast-enhanced dynamic imaging criteria. The recommended techniques are contrast-enhanced CT or contrast-enhanced MRI. Contrast-enhanced US is employed more in the positive diagnosis of HCC than in post-therapeutic monitoring. Although contrast enhancement is an important finding on imaging, enhancement does not necessarily depict the same phenomenon across modalities. We need to become well acquainted with the characteristics of each modality, including not only contrast-enhanced CT and MRI but also contrast-enhanced US. Many nonsurgical treatment options are now available for unresectable HCC, and accurate assessment of tumor response is essential to achieve favorable outcomes. For the assessment of successful radiofrequency ablation (RFA), the achievement of a sufficient ablation margin as well the absence of tumor vascular enhancement is essential. To evaluate the response to transcatheter arterial chemoembolization (TACE), enhanced tumor shrinkage is relied on as a measure of antitumor activity. Here, we give an overview of the current status of imaging assessment of HCC response to nonsurgical treatments including RFA and TACE.

  10. Single-Step Assembly of Multi-Modal Imaging Nanocarriers: MRI and Long-Wavelength Fluorescence Imaging

    PubMed Central

    Pinkerton, Nathalie M.; Gindy, Marian E.; Calero-DdelC, Victoria L.; Wolfson, Theodore; Pagels, Robert F.; Adler, Derek; Gao, Dayuan; Li, Shike; Wang, Ruobing; Zevon, Margot; Yao, Nan; Pacheco, Carlos; Therien, Michael J.; Rinaldi, Carlos; Sinko, Patrick J.

    2015-01-01

    MRI and NIR-active, multi-modal Composite NanoCarriers (CNCs) are prepared using a simple, one-step process, Flash NanoPrecipitation (FNP). The FNP process allows for the independent control of the hydrodynamic diameter, co-core excipient and NIR dye loading, and iron oxide-based nanocrystal (IONC) content of the CNCs. In the controlled precipitation process, 10 nm IONCs are encapsulated into poly(ethylene glycol) stabilized CNCs to make biocompatible T2 contrast agents. By adjusting the formulation, CNC size is tuned between 80 and 360 nm. Holding the CNC size constant at an intensity weighted average diameter of 99 ± 3 nm (PDI width 28 nm), the particle relaxivity varies linearly with encapsulated IONC content ranging from 66 to 533 mM-1s-1 for CNCs formulated with 4 to 16 wt% IONC. To demonstrate the use of CNCs as in vivo MRI contrast agents, CNCs are surface functionalized with liver targeting hydroxyl groups. The CNCs enable the detection of 0.8 mm3 non-small cell lung cancer metastases in mice livers via MRI. Incorporating the hydrophobic, NIR dye PZn3 into CNCs enables complementary visualization with long-wavelength fluorescence at 800 nm. In vivo imaging demonstrates the ability of CNCs to act both as MRI and fluorescent imaging agents. PMID:25925128

  11. Articulated dual modality photoacoustic and optical coherence tomography probe for preclinical and clinical imaging (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Liu, Mengyang; Zabihian, Behrooz; Weingast, Jessika; Hermann, Boris; Chen, Zhe; Zhang, Edward Z.; Beard, Paul C.; Pehamberger, Hubert; Drexler, Wolfgang

    2016-03-01

    The combination of photoacoustic tomography (PAT) with optical coherence tomography (OCT) has seen steady progress over the past few years. With the benchtop and semi-benchtop configurations, preclinical and clinical results have been demonstrated, paving the way for wider applications using dual modality PAT/OCT systems. However, as for the most updated semi-benchtop PAT/OCT system which employs a Fabry-Perot polymer film sensor, it is restricted to only human palm imaging due to the limited flexibility of the probe. The passband limit of the polymer film sensor further restricts the OCT source selection and reduces the sensitivity of the combined OCT system. To tackle these issues, we developed an articulated PAT/OCT probe for both preclinical and clinical applications. In the probe design, the sample arm of OCT sub-system and the interrogation part of the PAT sub-system are integrated into one compact unit. The polymer film sensor has a quick release function so that before each OCT scan, the sensor can be taken off to avoid the sensitivity drop and artefacts in OCT. The holding mechanism of the sensor is also more compact compared to previous designs, permitting access to uneven surfaces of the subjects. With the help of the articulated probe and a patient chair, we are able to perform co-registered imaging on human subjects on both upper and lower extremities while they are at rest positions. An increase in performance characteristics is also achieved. Patients with skin diseases are currently being recruited to test its clinical feasibility.

  12. SPECT/NIRF Dual Modality Imaging for Detection of Intraperitoneal Colon Tumor with an Avidin/Biotin Pretargeting System.

    PubMed

    Dong, Chengyan; Yang, Sujuan; Shi, Jiyun; Zhao, Huiyun; Zhong, Lijun; Liu, Zhaofei; Jia, Bing; Wang, Fan

    2016-01-06

    We describe herein dual-modality imaging of intraperitoneal colon tumor using an avidin/biotin pretargeting system. A novel dual-modality probe, (99m)Tc-HYNIC-lys(Cy5.5)-PEG4-biotin, was designed, synthesized and characterized. Single-photon emission computed tomography/ computed tomography (SPECT/CT) imaging and near infrared fluorescence (NIRF) imaging were developed using intraperitoneal LS180 human colon adenocarcinoma xenografts. Following avidin preinjection for 4 hours, (99m)Tc-HYNIC-lys(Cy5.5)-PEG4-biotin could successfully detect colon tumors of different sizes inside the abdominal region using both modalities, and the imaging results showed no differences. Biodistribution studies demonstrated that the tumors had a very high uptake of the probe (99m)Tc-HYNIC-lys(Cy5.5)-PEG4-biotin (12.74 ± 1.89% ID/g at 2 h p.i.), and the clearance from blood and other normal tissues occured very fast. The low tumor uptake in the non-pretargeted mice (1.63 ± 0.50% ID/g at 2 h p.i.) and tumor cell staining results showed excellent tumor binding specificity of the pretargeting system. The ability of the novel probe to show excellent imaging quality with high tumor-to-background contrast, a high degree of binding specificity with tumors and excellent in vivo biodistribution pharmacokinetics should prove that the avidin/biotin based dual-modality pretargeting probe is a promising imaging tool during the entire period of tumor diagnosis and treatment.

  13. Integration of sparse multi-modality representation and anatomical constraint for isointense infant brain MR image segmentation.

    PubMed

    Wang, Li; Shi, Feng; Gao, Yaozong; Li, Gang; Gilmore, John H; Lin, Weili; Shen, Dinggang

    2014-04-01

    Segmentation of infant brain MR images is challenging due to poor spatial resolution, severe partial volume effect, and the ongoing maturation and myelination processes. During the first year of life, the brain image contrast between white and gray matters undergoes dramatic changes. In particular, the image contrast inverses around 6-8months of age, where the white and gray matter tissues are isointense in T1 and T2 weighted images and hence exhibit the extremely low tissue contrast, posing significant challenges for automated segmentation. In this paper, we propose a general framework that adopts sparse representation to fuse the multi-modality image information and further incorporate the anatomical constraints for brain tissue segmentation. Specifically, we first derive an initial segmentation from a library of aligned images with ground-truth segmentations by using sparse representation in a patch-based fashion for the multi-modality T1, T2 and FA images. The segmentation result is further iteratively refined by integration of the anatomical constraint. The proposed method was evaluated on 22 infant brain MR images acquired at around 6months of age by using a leave-one-out cross-validation, as well as other 10 unseen testing subjects. Our method achieved a high accuracy for the Dice ratios that measure the volume overlap between automated and manual segmentations, i.e., 0.889±0.008 for white matter and 0.870±0.006 for gray matter.

  14. Application of 18F-FDG PET and diffusion weighted imaging (DWI) in multiple myeloma: comparison of functional imaging modalities

    PubMed Central

    Sachpekidis, Christos; Mosebach, Jennifer; Freitag, Martin T; Wilhelm, Thomas; Mai, Elias K; Goldschmidt, Hartmut; Haberkorn, Uwe; Schlemmer, Heinz-Peter; Delorme, Stefan; Dimitrakopoulou-Strauss, Antonia

    2015-01-01

    Aim of this prospective study was to assess the sensitivity of positron emission tomography (PET) and diffusion-weighted imaging (DWI) in detecting multiple myeloma (MM) lesions, using the well-established morphologic modalities magnetic resonance imaging (MRI) and computed tomography (CT) as the standard of reference (RS). The study included 24 MM patients (15 newly diagnosed, 9 pre-treated). All underwent 18F-FDG PET/CT and wholebody DWI. The findings in PET and DWI were compared to matching imaging findings in combined non-enhanced T1w, fat-saturated T2w (TIRM)- MRI, and low-dose CT. Patient-based analysis revealed that 15/24 patients (10 primary MM, 5 pre-treated) had myeloma lesions according to our RS. PET was positive in 13/24 patients (11 primary MM, 2 pre-treated) and DWI in 18/24 patients (12 primary MM, 6 pre-treated). Lesion-based analysis demonstrated 128 MM lesions, of which PET depicted 60/128 lesions (sensitivity 47%), while DWI depicted 99/128 lesions (sensitivity 77%). Further analysis including only the 15 untreated MM patients revealed a sensitivity of 90% for both PET and DWI and an overall concordance of PET and DWI of 72%. In conclusion, DWI was more sensitive than 18F-FDG PET in detecting myeloma lesions in a mixed population of primary and pre-treated MM patients. However, 18F-FDG PET and DWI demonstrated equivalent sensitivities in the sub-population of primary, untreated MM patients. This higher sensitivity of DWI in pre-treated patients may be due to the fact that 18F-FDG PET becomes negative earlier in the course of treatment in contrary to MRI, in which already treated lesions can remain visible. PMID:26550539

  15. Imaging requirements for medical applications of additive manufacturing.

    PubMed

    Huotilainen, Eero; Paloheimo, Markku; Salmi, Mika; Paloheimo, Kaija-Stiina; Björkstrand, Roy; Tuomi, Jukka; Markkola, Antti; Mäkitie, Antti

    2014-02-01

    Additive manufacturing (AM), formerly known as rapid prototyping, is steadily shifting its focus from industrial prototyping to medical applications as AM processes, bioadaptive materials, and medical imaging technologies develop, and the benefits of the techniques gain wider knowledge among clinicians. This article gives an overview of the main requirements for medical imaging affected by needs of AM, as well as provides a brief literature review from existing clinical cases concentrating especially on the kind of radiology they required. As an example application, a pair of CT images of the facial skull base was turned into 3D models in order to illustrate the significance of suitable imaging parameters. Additionally, the model was printed into a preoperative medical model with a popular AM device. Successful clinical cases of AM are recognized to rely heavily on efficient collaboration between various disciplines - notably operating surgeons, radiologists, and engineers. The single main requirement separating tangible model creation from traditional imaging objectives such as diagnostics and preoperative planning is the increased need for anatomical accuracy in all three spatial dimensions, but depending on the application, other specific requirements may be present as well. This article essentially intends to narrow the potential communication gap between radiologists and engineers who work with projects involving AM by showcasing the overlap between the two disciplines.

  16. Radiation burden from secondary doses to patients undergoing radiation therapy with photons and light ions and radiation doses from imaging modalities.

    PubMed

    Gudowska, I; Ardenfors, O; Toma-Dasu, I; Dasu, A

    2014-10-01

    Ionising radiation is increasingly used for the treatment of cancer, being the source of a considerable fraction of the medical irradiation to patients. With the increasing success rate of cancer treatments and longer life expectancy of the treated patients, the issue of secondary cancer incidence is of growing concern, especially for paediatric patients who may live long after the treatment and be more susceptible to carcinogenesis. Also, additional imaging procedures like computed tomography, kilovoltage and megavoltage imaging and positron emission tomography, alone or in conjunction with radiation therapy, may add to the radiation burden associated with the risk of occurrence of secondary cancers. This work has been based on literature studies and is focussed on the assessment of secondary doses to healthy tissues that are delivered by the use of modern radiation therapy and diagnostic imaging modalities in the clinical environment.

  17. Intrinsically 89Zr-labeled Gd2O2S:Eu nanophosphors with high in vivo stability for dual-modality imaging

    PubMed Central

    Ai, Fanrong; Goel, Shreya; Zhan, Yonghua; Valdovinos, Hector F; Chen, Feng; Barnhart, Todd E; Cai, Weibo

    2016-01-01

    Radioluminescence imaging (RLI) employs high energy particles from radioisotope decay for in situ excitation of selected nanophosphors. Co-injection of radiopharmaceuticals and nanophosphors suffers from suboptimal RL efficiency owing to the large separation between the source and the emitter. In addition, vastly different pharmacokinetic profiles of the two further impede the practical applications of this approach. To overcome the above challenges, chelator-free radiolabeled nanophosphors with excellent RL efficiency and dual-modality imaging capabilities have been proposed. Abundant O2- donors on Gd2O2S:Eu could intrinsically chelate oxophilic radionuclide 89Zr with ~80 % labeling yield. Positron emission tomography demonstrated superb long-term radiostability of [89Zr]Gd2O2S:Eu@PEG nanoparticles in vivo, and a conventional optical imaging system was used to study radiouminescence properties of [89Zr]Gd2O2S:Eu@PEG nanoparticles in vitro and in vivo. PMID:28078029

  18. One-pot aqueous synthesis of gadolinium doped CdTe quantum dots with dual imaging modalities.

    PubMed

    Jiang, Chunli; Shen, Zhitao; Luo, Chunhua; Lin, Hechun; Huang, Rong; Wang, Yiting; Peng, Hui

    2016-08-01

    A facile one-pot strategy has been developed for the aqueous synthesis of Gd doped CdTe (Gd:CdTe) QDs as fluorescence and magnetic resonance imaging dual-modal agent. The prepared Gd:CdTe QDs showed narrow size distribution and the average size was less than 5nm. The amount of Gd(3+) dopant in Gd:CdTe QDs significantly affected the optical properties of obtained QDs. The highest PL QY for the prepared Gd:CdTe QDs was up to 42.5%. The QDs showed the weak toxicity and significant enhancement in MRI signal. The specific relaxivity value (r1) was determined to be 4.22mM(-1)s(-1). These properties make the prepared Gd:CdTe QDs be an effective dual-modal imaging agent and have great potential applications in biomedical field.

  19. IMAGES: A digital computer program for interactive modal analysis and gain estimation for eigensystem synthesis

    NASA Technical Reports Server (NTRS)

    Jones, R. L.

    1984-01-01

    An interactive digital computer program for modal analysis and gain estimation for eigensystem synthesis was written. Both mathematical and operation considerations are described; however, the mathematical presentation is limited to those concepts essential to the operational capability of the program. The program is capable of both modal and spectral synthesis of multi-input control systems. It is user friendly, has scratchpad capability and dynamic memory, and can be used to design either state or output feedback systems.

  20. Evaluation of multiple image-based modalities for image-guided radiation therapy (IGRT) of prostate carcinoma: A prospective study

    SciTech Connect

    Mayyas, Essa; Chetty, Indrin J.; Chetvertkov, Mikhail; Wen, Ning; Neicu, Toni; Nurushev, Teamor; Ren Lei; Pradhan, Deepak; Movsas, Benjamin; Elshaikh, Mohamed A.; Lu Mei; Stricker, Hans

    2013-04-15

    Purpose: Setup errors and prostate intrafraction motion are main sources of localization uncertainty in prostate cancer radiation therapy. This study evaluates four different imaging modalities 3D ultrasound (US), kV planar images, cone-beam computed tomography (CBCT), and implanted electromagnetic transponders (Calypso/Varian) to assess inter- and intrafraction localization errors during intensity-modulated radiation therapy based treatment of prostate cancer. Methods: Twenty-seven prostate cancer patients were enrolled in a prospective IRB-approved study and treated to a total dose of 75.6 Gy (1.8 Gy/fraction). Overall, 1100 fractions were evaluated. For each fraction, treatment targets were localized using US, kV planar images, and CBCT in a sequence defined to determine setup offsets relative to the patient skin tattoos, intermodality differences, and residual errors for each patient and patient cohort. Planning margins, following van Herk's formalism, were estimated based on error distributions. Calypso-based localization was not available for the first eight patients, therefore centroid positions of implanted gold-seed markers imaged prior to and immediately following treatment were used as a motion surrogate during treatment. For the remaining 19 patients, Calypso transponders were used to assess prostate intrafraction motion. Results: The means ({mu}), and standard deviations (SD) of the systematic ({Sigma}) and random errors ({sigma}) of interfraction prostate shifts (relative to initial skin tattoo positioning), as evaluated using CBCT, kV, and US, averaged over all patients and fractions, were: [{mu}{sub CBCT}= (-1.2, 0.2, 1.1) mm, {Sigma}{sub CBCT}= (3.0, 1.4, 2.4) mm, {sigma}{sub CBCT}= (3.2, 2.2, 2.5) mm], [{mu}{sub kV}= (-2.9, -0.4, 0.5) mm, {Sigma}{sub kV}= (3.4, 3.1, 2.6) mm, {sigma}{sub kV}= (2.9, 2.0, 2.4) mm], and [{mu}{sub US}= (-3.6, -1.4, 0.0) mm, {Sigma}{sub US}= (3.3, 3.5, 2.8) mm, {sigma}{sub US}= (4.1, 3.8, 3.6) mm], in the anterior

  1. Enhanced Visualization of Subtle Outer Retinal Pathology by En Face Optical Coherence Tomography and Correlation with Multi-Modal Imaging

    PubMed Central

    Chew, Avenell L.; Lamey, Tina; McLaren, Terri; De Roach, John

    2016-01-01

    Purpose To present en face optical coherence tomography (OCT) images generated by graph-search theory algorithm-based custom software and examine correlation with other imaging modalities. Methods En face OCT images derived from high density OCT volumetric scans of 3 healthy subjects and 4 patients using a custom algorithm (graph-search theory) and commercial software (Heidelberg Eye Explorer software (Heidelberg Engineering)) were compared and correlated with near infrared reflectance, fundus autofluorescence, adaptive optics flood-illumination ophthalmoscopy (AO-FIO) and microperimetry. Results Commercial software was unable to generate accurate en face OCT images in eyes with retinal pigment epithelium (RPE) pathology due to segmentation error at the level of Bruch’s membrane (BM). Accurate segmentation of the basal RPE and BM was achieved using custom software. The en face OCT images from eyes with isolated interdigitation or ellipsoid zone pathology were of similar quality between custom software and Heidelberg Eye Explorer software in the absence of any other significant outer retinal pathology. En face OCT images demonstrated angioid streaks, lesions of acute macular neuroretinopathy, hydroxychloroquine toxicity and Bietti crystalline deposits that correlated with other imaging modalities. Conclusions Graph-search theory algorithm helps to overcome the limitations of outer retinal segmentation inaccuracies in commercial software. En face OCT images can provide detailed topography of the reflectivity within a specific layer of the retina which correlates with other forms of fundus imaging. Our results highlight the need for standardization of image reflectivity to facilitate quantification of en face OCT images and longitudinal analysis. PMID:27959968

  2. A dual-modal magnetic nanoparticle probe for preoperative and intraoperative mapping of sentinel lymph nodes by magnetic resonance and near infrared fluorescence imaging.

    PubMed

    Zhou, Zhengyang; Chen, Hongwei; Lipowska, Malgorzata; Wang, Liya; Yu, Qiqi; Yang, Xiaofeng; Tiwari, Diana; Yang, Lily; Mao, Hui

    2013-07-01

    The ability to reliably detect sentinel lymph nodes for sentinel lymph node biopsy and lymphadenectomy is important in clinical management of patients with metastatic cancers. However, the traditional sentinel lymph node mapping with visible dyes is limited by the penetration depth of light and fast clearance of the dyes. On the other hand, sentinel lymph node mapping with radionucleotide technique has intrinsically low spatial resolution and does not provide anatomic details in the sentinel lymph node mapping procedure. This work reports the development of a dual modality imaging probe with magnetic resonance and near infrared imaging capabilities for sentinel lymph node mapping using magnetic iron oxide nanoparticles (10 nm core size) conjugated with a near infrared molecule with emission at 830 nm. Accumulation of magnetic iron oxide nanoparticles in sentinel lymph nodes leads to strong T2 weighted magnetic resonance imaging contrast that can be potentially used for preoperative localization of sentinel lymph nodes, while conjugated near infrared molecules provide optical imaging tracking of lymph nodes with a high signal to background ratio. The new magnetic nanoparticle based dual imaging probe exhibits a significant longer lymph node retention time. Near infrared signals from nanoparticle conjugated near infrared dyes last up to 60 min in sentinel lymph node compared to that of 25 min for the free near infrared dyes in a mouse model. Furthermore, axillary lymph nodes, in addition to sentinel lymph nodes, can be also visualized with this probe, given its slow clearance and sufficient sensitivity. Therefore, this new dual modality imaging probe with the tissue penetration and sensitive detection of sentinel lymph nodes can be applied for preoperative survey of lymph nodes with magnetic resonance imaging and allows intraoperative sentinel lymph node mapping using near infrared optical devices.

  3. Multifunctional dendrimer-based nanoparticles for in vivo MR/CT dual-modal molecular imaging of breast cancer

    PubMed Central

    Li, Kangan; Wen, Shihui; Larson, Andrew C; Shen, Mingwu; Zhang, Zhuoli; Chen, Qian; Shi, Xiangyang; Zhang, Guixiang

    2013-01-01

    Development of dual-mode or multi-mode imaging contrast agents is important for accurate and self-confirmatory diagnosis of cancer. We report a new multifunctional, dendrimer-based gold nanoparticle (AuNP) as a dual-modality contrast agent for magnetic resonance (MR)/computed tomography (CT) imaging of breast cancer cells in vitro and in vivo. In this study, amine-terminated generation 5 poly(amidoamine) dendrimers modified with gadolinium chelate (DOTA-NHS) and polyethylene glycol monomethyl ether were used as templates to synthesize AuNPs, followed by Gd(III) chelation and acetylation of the remaining dendrimer terminal amine groups; multifunctional dendrimer-entrapped AuNPs (Gd-Au DENPs) were formed. The formed Gd-Au DENPs were used for both in vitro and in vivo MR/CT imaging of human MCF-7 cancer cells. Both MR and CT images demonstrate that MCF-7 cells and the xenograft tumor model can be effectively imaged. The Gd-Au DENPs uptake, mainly in the cell cytoplasm, was confirmed by transmission electron microscopy. The cell cytotoxicity assay, cell morphology observation, and flow cytometry show that the developed Gd-Au DENPs have good biocompatibility in the given concentration range. Our results clearly suggest that the synthetic Gd-Au DENPs are amenable for dual-modality MR/CT imaging of breast cancer cells. PMID:23888113

  4. Investigating oyster shell thickness and strength using three imaging modalities: hyperspectral imaging, thermal imaging and digital photography

    NASA Astrophysics Data System (ADS)

    Mehrübeoglu, Mehrube; Smith, Dustin K.; Smith, Shane W.; Smee, Delbert L.; Simionescu, Petru-Aurelian

    2013-09-01

    A comparative study of three imaging technologies has been conducted to nondestructively assess the thickness and strength of oyster shells grown in various environmental conditions. Oyster shell thickness and strength are expected to be dependent on the harshness of the oyster's environment as well as other factors. Oysters have been grown in environments with and without predators, and within and out of tidal zones. Hyperspectral imaging has been used to detect possible differences in hyperspectral properties among oyster shells from each of the four environments. Thermal Imaging has been utilized to identify hot spots in the shells based on the principles of heat capacitance, indicating density or thickness of the shells. Finally, a visible-range digital photographic camera has been used to obtain digital images. The three technologies are compared to evaluate the effectiveness of each technology in identifying oyster shell thickness and strength. Although oyster shell thickness and strength are related, they may not be exactly correlated. The local thickness of the oyster shells have been measured with a micro caliper, and shells broken with a crush tester to establish a baseline and ground truth for average shell thickness and shell strength, respectively. The preliminary results from the three methods demonstrate that thermal imaging correlates the best with the invasive strength test results and weight measurements. Using hyperspectral data and principal component analysis, classification of the four oyster shell groups were achieved. Visible-range images mainly provided size, shape, color and texture information.

  5. MO-DE-210-03: Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities

    SciTech Connect

    Ding, K.

    2015-06-15

    Ultrasound imaging is an attractive method for image guided radiation treatment (IGRT), by itself or to complement other imaging modalities. It is inexpensive, portable and provides good soft tissue contrast. For challenging soft tissue targets such as pancreatic cancer, ultrasound imaging can be used in combination with pre-treatment MRI and/or CT to transfer important anatomical features for target localization at time of treatment. The non-invasive and non-ionizing nature of ultrasound imaging is particularly powerful for intra-fraction localization and monitoring. Recognizing these advantages, efforts are being made to incorporate novel robotic approaches to position and manipulate the ultrasound probe during irradiation. These recent enabling developments hold potential to bring ultrasound imaging to a new level of IGRT applications. However, many challenges, not limited to image registration, robotic deployment, probe interference and image acquisition rate, need to be addressed to realize the full potential of IGRT with ultrasound imaging. Learning Objectives: Understand the benefits and limitations in using ultrasound to augment MRI and/or CT for motion monitoring during radiation therapy delivery. Understanding passive and active robotic approaches to implement ultrasound imaging for intra-fraction monitoring. Understand issues of probe interference with radiotherapy treatment. Understand the critical clinical workflow for effective and reproducible IGRT using ultrasound guidance. The work of X.L. is supported in part by Elekta; J.W. and K.D. is supported in part by a NIH grant R01 CA161613 and by Elekta; D.H. is support in part by a NIH grant R41 CA174089.

  6. Night-time ground hyperspectral imaging for urban-scale remote sensing of ambient PM--modal concentrations retrieval.

    PubMed

    Etzion, Yael; Kolatt, Tsafrir; Shoshany, Maxim; Broday, David M

    2014-01-01

    Retrieval of aerosol loading in vertical atmospheric columns is a common product of satellite and ground instruments that measure spectral extinction of solar radiation throughout the entire atmosphere. Here we study ground hyperspectral imaging of artificial light sources as a complementary method for retrieving fine aerosol concentrations along quazi-horizontal ambient open paths. Previously, we reported hyperspectral measurements of the aerosol optical thickness in the 500-900 nm range over urban-scale distances (180 m to 4 km), measuring the extinction of radiation emitted from a halogen source. Here we confirm in a laboratory-setup the basic premise that different accumulation-size aerosols generate distinct hyperspectral signatures in this spectral range. Measured hyperspectral attenuation signatures of fine aerosols were comparable to calculated Mie scattering signatures, suggesting that modal aerosol concentrations can be retrieved. A genetic algorithm was adapted to estimate the aerosol modal concentrations from its hyperspectral extinction signature. Retrievals of aerosol concentrations from measured and synthetic hyperspectral signatures indicated a robust algorithm, with an expected retrieval error of 0.2-22% for typical ambient concentrations along an urban-scale open path. The retrieval accuracy was found to depend on the relative aerosol modal concentrations, especially when there is a substantial overlap between the modal spectral signatures.

  7. Epi-detected quadruple-modal nonlinear optical microscopy for label-free imaging of the tooth

    SciTech Connect

    Wang, Zi; Zheng, Wei; Huang, Zhiwei; Stephen Hsu, Chin-Ying

    2015-01-19

    We present an epi-detected quadruple-modal nonlinear optical microscopic imaging technique (i.e., coherent anti-Stokes Raman scattering (CARS), second-harmonic generation (SHG), third-harmonic generation (THG), and two-photon excited fluorescence (TPEF)) based on a picosecond (ps) laser-pumped optical parametric oscillator system for label-free imaging of the tooth. We demonstrate that high contrast ps-CARS images covering both the fingerprint (500–1800 cm{sup −1}) and high-wavenumber (2500–3800 cm{sup −1}) regions can be acquired to uncover the distributions of mineral and organic biomaterials in the tooth, while high quality TPEF, SHG, and THG images of the tooth can also be acquired under ps laser excitation without damaging the samples. The quadruple-modal nonlinear microscopic images (CARS/SHG/THG/TPEF) acquired provide better understanding of morphological structures and biochemical/biomolecular distributions in the dentin, enamel, and the dentin-enamel junction of the tooth without labeling, facilitating optical diagnosis and characterization of the tooth in dentistry.

  8. Prototype study on a miniaturized dual-modality imaging system for photoacoustic microscopy and confocal fluorescence microscopy

    NASA Astrophysics Data System (ADS)

    Chen, Sung-Liang; Xie, Zhixing; Guo, L. Jay; Wang, Xueding

    2014-03-01

    It is beneficial to study tumor angiogenesis and microenvironments by imaging the microvasculature and cells at the same time. Photoacoustic microscopy (PAM) is capable of sensitive three-dimensional mapping of microvasculature, while fluorescence microscopy may be applied to assessment of tissue pathology. In this work, a fiber-optic based PAM and confocal fluorescence microscopy (CFM) dual-modality imaging system was designed and built, serving as a prototype of a miniaturized dual-modality imaging probe for endoscopic applications. As for the design, we employed miniature components, including a microelectromechanical systems (MEMS) scanner, a miniature objective lens, and a small size optical microring resonator as an acoustic detector. The system resolutions were calibrated as 8.8 μm in the lateral directions for both PAM and CFM, and 19 μm and 53 μm in the axial direction for PAM and CFM, respectively. Images of the animal bladders ex vivo were demonstrated to show the ability of the system in imaging not only microvasculature but also cellular structure.

  9. Performance evaluation of a compact PET/SPECT/CT tri-modality system for small animal imaging applications

    NASA Astrophysics Data System (ADS)

    Wei, Qingyang; Wang, Shi; Ma, Tianyu; Wu, Jing; Liu, Hui; Xu, Tianpeng; Xia, Yan; Fan, Peng; Lyu, Zhenlei; Liu, Yaqiang

    2015-06-01

    PET, SPECT and CT imaging techniques are widely used in preclinical small animal imaging applications. In this paper, we present a compact small animal PET/SPECT/CT tri-modality system. A dual-functional, shared detector design is implemented which enables PET and SPECT imaging with a same LYSO ring detector. A multi-pinhole collimator is mounted on the system and inserted into the detector ring in SPECT imaging mode. A cone-beam CT consisting of a micro focus X-ray tube and a CMOS detector is implemented. The detailed design and the performance evaluations are reported in this paper. In PET imaging mode, the measured NEMA based spatial resolution is 2.12 mm (FWHM), and the sensitivity at the central field of view (CFOV) is 3.2%. The FOV size is 50 mm (∅)×100 mm (L). The SPECT has a spatial resolution of 1.32 mm (FWHM) and an average sensitivity of 0.031% at the center axial, and a 30 mm (∅)×90 mm (L) FOV. The CT spatial resolution is 8.32 lp/mm @10%MTF, and the contrast discrimination function value is 2.06% with 1.5 mm size cubic box object. In conclusion, a compact, tri-modality PET/SPECT/CT system was successfully built with low cost and high performance.

  10. Epi-detected quadruple-modal nonlinear optical microscopy for label-free imaging of the tooth

    NASA Astrophysics Data System (ADS)

    Wang, Zi; Zheng, Wei; Stephen Hsu, Chin-Ying; Huang, Zhiwei

    2015-01-01

    We present an epi-detected quadruple-modal nonlinear optical microscopic imaging technique (i.e., coherent anti-Stokes Raman scattering (CARS), second-harmonic generation (SHG), third-harmonic generation (THG), and two-photon excited fluorescence (TPEF)) based on a picosecond (ps) laser-pumped optical parametric oscillator system for label-free imaging of the tooth. We demonstrate that high contrast ps-CARS images covering both the fingerprint (500-1800 cm-1) and high-wavenumber (2500-3800 cm-1) regions can be acquired to uncover the distributions of mineral and organic biomaterials in the tooth, while high quality TPEF, SHG, and THG images of the tooth can also be acquired under ps laser excitation without damaging the samples. The quadruple-modal nonlinear microscopic images (CARS/SHG/THG/TPEF) acquired provide better understanding of morphological structures and biochemical/biomolecular distributions in the dentin, enamel, and the dentin-enamel junction of the tooth without labeling, facilitating optical diagnosis and characterization of the tooth in dentistry.

  11. Synthesis of heterodimer radionuclide nanoparticles for magnetic resonance and single-photon emission computed tomography dual-modality imaging

    NASA Astrophysics Data System (ADS)

    Zhu, Jing; Zhang, Bin; Tian, Jian; Wang, Jiaqing; Chong, Yu; Wang, Xin; Deng, Yaoyao; Tang, Minghua; Li, Yonggang; Ge, Cuicui; Pan, Yue; Gu, Hongwei

    2015-02-01

    We report a facile synthesis of bifunctional Fe3O4-Ag125I heterodimers for use as dual-modality imaging agents in magnetic resonance (MR) and single-photon emission computed tomography (SPECT). We introduced 125I, which is a clinically used radioisotope, as a SPECT reporter, into Fe3O4-Ag heterodimer nanoparticles to provide a new type of bifunctional contrast agent for MRI and SPECT imaging.We report a facile synthesis of bifunctional Fe3O4-Ag125I heterodimers for use as dual-modality imaging agents in magnetic resonance (MR) and single-photon emission computed tomography (SPECT). We introduced 125I, which is a clinically used radioisotope, as a SPECT reporter, into Fe3O4-Ag heterodimer nanoparticles to provide a new type of bifunctional contrast agent for MRI and SPECT imaging. Electronic supplementary information (ESI) available: Details of general experimental procedures, TEM image. See DOI: 10.1039/c4nr07255c

  12. Comparison study of five different display modalities for whole slide images in surgical pathology and cytopathology in Europe

    NASA Astrophysics Data System (ADS)

    D'Haene, Nicky; Maris, Calliope; Rorive, Sandrine; Moles Lopez, Xavier; Rostang, Johan; Marchessoux, Cédric; Pantanowitz, Liron; Parwani, Anil V.; Salmon, Isabelle

    2013-03-01

    User experience with viewing images in pathology is crucial for accurate interpretation and diagnosis. With digital pathology, images are being read on a display system, and this poses new types of questions: such as what is the difference in terms of pixelation, refresh lag or obscured features compared to an optical microscope. Is there a resultant change in user performance in terms of speed of slide review, perception of adequacy and quality or in diagnostic confidence? A prior psychophysical study was carried out comparing various display modalities on whole slide imaging (WSI) in pathology at the University of Pittsburgh Medical Center (UPMC) in the USA. This prior study compared professional and non-professional grade display modalities and highlighted the importance of using a medical grade display to view pathological digital images. This study was duplicated in Europe at the Department of Pathology in Erasme Hospital (Université Libre de Bruxelles (ULB)) in an attempt to corroborate these findings. Digital WSI with corresponding glass slides of 58 cases including surgical pathology and cytopathology slides of varying difficulty were employed. Similar non-professional and professional grade display modalities were compared to an optical microscope (Olympus BX51). Displays ranged from a laptop (DELL Latitude D620), to a consumer grade display (DELL E248WFPb), to two professional grade monitors (Eizo CG245W and Barco MDCC-6130). Three pathologists were selected from the Department of Pathology in Erasme Hospital (ULB) in Belgium to view and interpret the pathological images on these different displays. The results show that non-professional grade displays (laptop and consumer) have inferior user experience compared to professional grade monitors and the optical microscope.

  13. Enhancement of Glossiness Perception by Retinal-Image Motion: Additional Effect of Head-Yoked Motion Parallax

    PubMed Central

    Tani, Yusuke; Araki, Keisuke; Nagai, Takehiro; Koida, Kowa; Nakauchi, Shigeki; Kitazaki, Michiteru

    2013-01-01

    It has been argued that when an observer moves, a contingent retinal-image motion of a stimulus would strengthen the perceived glossiness. This would be attributed to the veridical perception of three-dimensional structure by motion parallax. However, it has not been investigated whether the effect of motion parallax is more than that of retinal-image motion of the stimulus. Using a magnitude estimation method, we examine in this paper whether cross-modal coordination of the stimulus change and the observer's motion (i.e., motion parallax) is essential or the retinal-image motion alone is sufficient for enhancing the perceived glossiness. Our data show that a retinal-image motion simulating motion parallax without head motion strengthened the perceived glossiness but that its effect was weaker than that of motion parallax with head motion. These results suggest the existence of an additional effect of the cross-modal coordination between vision and proprioception on glossiness perception. That is, motion parallax enhances the perception of glossiness, in addition to retinal-image motions of specular surfaces. PMID:23336006

  14. Contemporary Diagnostic Imaging Modalities for the Staging and Surveillance of Melanoma Patients: a Meta-analysis

    PubMed Central

    Xing, Yan; Bronstein, Yulia; Ross, Merrick I.; Askew, Robert L.; Lee, Jeffrey E.; Gershenwald, Jeffrey E.; Royal, Richard

    2011-01-01

    Background Meta-analyses were performed to examine the utility of ultrasonography, computed tomography (CT), positron emission tomography (PET), and a combination of both (PET-CT) for the staging and surveillance of melanoma patients. Method Patient-level data from 74 studies containing 10 528 patients (between January 1, 1990, and June, 30, 2009) were used to derive characteristics of the diagnostic tests used. Meta-analyses were conducted by use of Bayesian bivariate binomial models to estimate sensitivity and specificity. Diagnostic odds ratios [ie, true-positive results/false-negative results)/(false-positive results/true-negative results)] and their 95% credible intervals (CrIs) and positive predictive values were used as indicators of test performance. Results Among the four imaging methods examined for the staging of regional lymph nodes, ultrasonography had the highest sensitivity (60%, 95% CrI = 33% to 83%), specificity (97%, 95% CrI = 88% to 99%), and diagnostic odds ratio (42, 95% CrI = 8.08 to 249.8). For staging of distant metastases, PET-CT had the highest sensitivity (80%, 95% CrI = 53% to 93%), specificity (87%, 95% CrI = 54% to 97%), and diagnostic odds ratio (25, 95% CrI = 3.58 to 198.7). Similar trends were observed for melanoma surveillance of lymph node involvement, with ultrasonography having the highest sensitivity (96%, 95% CrI = 85% to 99%), specificity (99%, 95% CrI = 95% to 100%), and diagnostic odds ratio (1675, 95% CrI = 226.6 to 15,920). For distant metastases, PET-CT had the highest sensitivity (86%, 95% CrI = 76% to 93%), specificity (91%, 95% CrI = 79% to 97%), and diagnostic odds ratio (67, 95% CrI = 20.42 to 229.7). Positive predictive values were likewise highest for ultrasonography in lymph node staging and for PET-CT in detecting distant metastases. Conclusion Among the compared modalities, ultrasonography was superior for detecting lymph node metastases, and PET-CT was superior for the detection of distant metastases in both

  15. Shape memory polymers with enhanced visibility for magnetic resonance- and X-ray imaging modalities.

    PubMed

    Weems, A C; Szafron, J M; Easley, A D; Herting, S; Smolen, J; Maitland, D J

    2017-03-01

    Currently, monitoring of minimally invasive medical devices is performed using fluoroscopy. The risks associated with fluoroscopy, including increased risk of cancer, make this method especially unsuitable for pediatric device delivery and follow-up procedures. A more suitable method is magnetic resonance (MR) imaging, which makes use of harmless magnetic fields rather than ionizing radiation when imaging the patient; this method is safer for both the patient and the performing technicians. Unfortunately, there is a lack of research available on bulk polymeric materials to enhance MR-visibility for use in medical devices. Here we show the incorporation of both physical and chemical modifying agents for the enhancement of both MR and X-ray visibility. Through the incorporation of these additives, we are able to control shape recovery of the polymer without sacrificing the thermal transition temperatures or the mechanical properties. For long-term implantation, these MR-visible materials do not have altered degradation profiles, and the release of additives is well below significant thresholds for daily dosages of MR-visible compounds. We anticipate our materials to be a starting point for safer, MR-visible medical devices incorporating polymeric components.

  16. WE-D-9A-04: Improving Multi-Modality Image Registration Using Edge-Based Transformations

    SciTech Connect

    Wang, Y; Tyagi, N; Veeraraghavan, H; Deasy, J

    2014-06-15

    Purpose: Multi-modality deformable image registration (DIR) for head and neck (HN) radiotherapy is difficult, particularly when matching computed tomography (CT) scans with magnetic resonance imaging (MRI) scans. We hypothesized that the ‘shared information’ between images of different modalities was to be found in some form of edge-based transformation, and that novel edge-based DIR methods might outperform standard DIR methods. Methods: We propose a novel method that combines gray-scale edge-based morphology and mutual information (MI) in two stages. In the first step, we applied a modification of a previously published mathematical morphology method as an efficient gray scale edge estimator, with denoising function. The results were fed into a MI-based solver (plastimatch). The method was tested on 5 HN patients with pretreatment CT and MR datasets and associated follow-up weekly MR scans. The followup MRs showed significant regression in tumor and normal structure volumes as compared to the pretreatment MRs. The MR images used in this study were obtained using fast spin echo based T2w images with a 1 mm isotropic resolution and FOV matching the CT scan. Results: In all cases, the novel edge-based registration method provided better registration quality than MI-based DIR using the original CT and MRI images. For example, the mismatch in carotid arteries was reduced from 3–5 mm to within 2 mm. The novel edge-based method with different registration regulation parameters did not show any distorted deformations as compared to the non-realistic deformations resulting from MI on the original images. Processing time was 1.3 to 2 times shorter (edge vs. non-edge). In general, we observed quality improvement and significant calculation time reduction with the new method. Conclusion: Transforming images to an ‘edge-space,’ if designed appropriately, greatly increases the speed and accuracy of DIR.

  17. Facile preparation of multifunctional uniform magnetic microspheres for T1-T2 dual modal magnetic resonance and optical imaging.

    PubMed

    Zhang, Li; Liang, Shuang; Liu, Ruiqing; Yuan, Tianmeng; Zhang, Shulai; Xu, Zushun; Xu, Haibo

    2016-08-01

    Molecular imaging is of significant importance for early detection and diagnosis of cancer. Herein, a novel core-shell magnetic microsphere for dual modal magnetic resonance imaging (MRI) and optical imaging was produced by one-pot emulsifier-free emulsion polymerization, which could provide high resolution rate of histologic structure information and realize high sensitive detection at the same time. The synthesized magnetic microspheres composed of cores containing oleic acid (OA) and sodium undecylenate (NaUA) modified Fe3O4 nanoparticles and styrene (St), Glycidyl methacrylate (GMA), and polymerizable lanthanide complexes (Gd(AA)3Phen and Eu(AA)3Phen) polymerized on the surface for outer shells. Fluorescence spectra show characteristic emission peaks from Eu(3+) at 590nm and 615nm and vivid red fluorescence luminescence can be observed by 2-photon confocal scanning laser microscopy (CLSM). In vitro cytotoxicity tests based on the MTT assay demonstrate good cytocompatibility, the composites have longitudinal relaxivity value (r1) of 8.39mM(-1)s(-1) and also have transverse relaxivity value (r2) of 71.18mM(-1)s(-1) at clinical 3.0 T MR scanner. In vitro and in vivo MRI studies exhibit high signal enhancement on both T1- and T2-weighted MR images. These fascinating multifunctional properties suggest that the polymer microspheres have large clinical potential as multi-modal MRI/optical probes.

  18. Color Tunable Gd-Zn-Cu-In-S/ZnS Quantum Dots for Dual Modality Magnetic Resonance and Fluorescence Imaging

    PubMed Central

    Guo, Weisheng; Yang, Weitao; Wang, Yu; Sun, Xiaolian; Liu, Zhongyun; Zhang, Bingbo

    2014-01-01

    Inorganic nanoparticles have been introduced into biological systems as useful probes for in vitro diagnosis and in vivo imaging, due to their relatively small size and exceptional physical and chemical properties. A new kind of color tunable Gd-Zn-Cu-In-S/ZnS (GZCIS/ZnS) quantum dots (QDs) with stable crystal structure was successfully synthesized and utilized for magnetic resonance (MR) and fluorescence dual modality imaging. This strategy allows successful fabrication of GZCIS/ZnS QDs by incorporating Gd into ZCIS/ZnS QDs to achieve great MR enhancement without compromising the fluorescence properties of the initial ZCIS/ZnS QDs. The as-prepared GZCIS/ZnS QDs show high T1 MR contrast as well as “color-tunable” photoluminescence (PL) in the range of 550–725 nm by adjusting the Zn/Cu feeding ratio with high PL quantum yield (QY). The GZCIS/ZnS QDs were transferred into water via a bovine serum albumin (BSA) coating strategy. The resulting Cd-free GZCIS/ZnS QDs reveal negligible cytotoxicity on both HeLa and A549 cells. Both fluorescence and MR imaging studies were successfully performed in vitro and in vivo. The results demonstrated that GZCIS/ZnS QDs could be a dual-modal contrast agent to simultaneously produce strong MR contrast enhancement as well as fluorescence emission for in vivo imaging. PMID:25485043

  19. Comparison of additive image fusion vs. feature-level image fusion techniques for enhanced night driving

    NASA Astrophysics Data System (ADS)

    Bender, Edward J.; Reese, Colin E.; Van Der Wal, Gooitzen S.

    2003-02-01

    The Night Vision & Electronic Sensors Directorate (NVESD) has conducted a series of image fusion evaluations under the Head-Tracked Vision System (HTVS) program. The HTVS is a driving system for both wheeled and tracked military vehicles, wherein dual-waveband sensors are directed in a more natural head-slewed imaging mode. The HTVS consists of thermal and image-intensified TV sensors, a high-speed gimbal, a head-mounted display, and a head tracker. A series of NVESD field tests over the past two years has investigated the degree to which additive (A+B) image fusion of these sensors enhances overall driving performance. Additive fusion employs a single (but user adjustable) fractional weighting for all the features of each sensor's image. More recently, NVESD and Sarnoff Corporation have begun a cooperative effort to evaluate and refine Sarnoff's "feature-level" multi-resolution (pyramid) algorithms for image fusion. This approach employs digital processing techniques to select at each image point only the sensor with the strongest features, and to utilize only those features to reconstruct the fused video image. This selection process is performed simultaneously at multiple scales of the image, which are combined to form the reconstructed fused image. All image fusion techniques attempt to combine the "best of both sensors" in a single image. Typically, thermal sensors are better for detecting military threats and targets, while image-intensified sensors provide more natural scene cues and detect cultural lighting. This investigation will address the differences between additive fusion and feature-level image fusion techniques for enhancing the driver's overall situational awareness.

  20. Synthesis and testing of modular dual-modality nanoparticles for magnetic resonance and multi-spectral photoacoustic imaging

    PubMed Central

    Bogdanov, Alexei A.; Dixon, Adam; Gupta, Suresh; Zhang, Lejie; Zheng, Shaokuan; Shazeeb, Mohammed S.; Zhang, Surong; Klibanov, Alexander L.

    2016-01-01

    Magnetic resonance (MR) and photoacoustic (PA) imaging are being currently investigated as complementing strategies for applications requiring sensitive detection of cells in vivo. While combined MR/PAI detection of cells requires biocompatible cell labeling probes, water-based synthesis of dual-modality MR/PAI probes presents significant technical challenges. Here we describe facile synthesis and characterization of hybrid modular dextran-stabilized gold/iron oxide (Au-IO) multimetallic nanoparticles (NP) enabling multimodal imaging of cells. The stable association between the IO and gold NP was achieved by priming the surface of dextran-coated IO with silver NP resulting from silver (I) reduction by aldehyde groups, which are naturally present within the dextran coating of IO at the level of 19-23 groups/particle. The Au-IO NP formed in the presence of silver-primed Au-IO were stabilized by using partially thiolated MPEG5-gPLL graft copolymer carrying residual amino groups. This stabilizer served as a carrier of near-infrared fluorophores (e.g. IRDye 800RS) for multispectral PA imaging. Dual modality imaging experiments performed in capillary phantoms of purified Au-IO-800RS NPs showed that these NPs were detectible using 3T MRI at a concentration of 25 μM iron. PA imaging achieved approximately 2.5-times higher detection sensitivity due to strong PA signal emissions at 530 and 770 nm, corresponding to gold plasmons and IRDye integrated into the coating of the hybrid NPs, respectively, with no “bleaching” of PA signal. MDA-MB-231 cells pre-labeled with Au-IO-800RS retained plasma membrane integrity and were detectable by using both MR and dual-wavelength PA at 49±3 cells/imaging voxel. We believe that modular assembly of multi-metallic NPs shows promise for imaging analysis of engineered cells and tissues with high resolution and sensitivity. PMID:26603129

  1. Cone Beam CT vs. Fan Beam CT: A Comparison of Image Quality and Dose Delivered Between Two Differing CT Imaging Modalities.

    PubMed

    Lechuga, Lawrence; Weidlich, Georg A

    2016-09-12

    A comparison of image quality and dose delivered between two differing computed tomography (CT) imaging modalities-fan beam and cone beam-was performed. A literature review of quantitative analyses for various image quality aspects such as uniformity, signal-to-noise ratio, artifact presence, spatial resolution, modulation transfer function (MTF), and low contrast resolution was generated. With these aspects quantified, cone beam computed tomography (CBCT) shows a superior spatial resolution to that of fan beam, while fan beam shows a greater ability to produce clear and anatomically correct images with better soft tissue differentiation. The results indicate that fan beam CT produces superior images to that of on-board imaging (OBI) cone beam CT systems, while providing a considerably less dose to the patient.

  2. Rational chemical design of the next generation of molecular imaging probes based on physics and biology: mixing modalities, colors and signals.

    PubMed

    Kobayashi, Hisataka; Longmire, Michelle R; Ogawa, Mikako; Choyke, Peter L

    2011-09-01

    In recent years, numerous in vivo molecular imaging probes have been developed. As a consequence, much has been published on the design and synthesis of molecular imaging probes focusing on each modality, each type of material, or each target disease. More recently, second generation molecular imaging probes with unique, multi-functional, or multiplexed characteristics have been designed. This critical review focuses on (i) molecular imaging using combinations of modalities and signals that employ the full range of the electromagnetic spectra, (ii) optimized chemical design of molecular imaging probes for in vivo kinetics based on biology and physiology across a range of physical sizes, (iii) practical examples of second generation molecular imaging probes designed to extract complementary data from targets using multiple modalities, color, and comprehensive signals (277 references).

  3. Rational chemical design of the next generation of molecular imaging probes based on physics and biology: mixing modalities, colors and signals

    PubMed Central

    Longmire, Michelle R.; Ogawa, Mikako; Choyke, Peter L.

    2012-01-01

    In recent years, numerous in vivo molecular imaging probes have been developed. As a consequence, much has been published on the design and synthesis of molecular imaging probes focusing on each modality, each type of material, or each target disease. More recently, second generation molecular imaging probes with unique, multi-functional, or multiplexed characteristics have been designed. This critical review focuses on (i) molecular imaging using combinations of modalities and signals that employ the full range of the electromagnetic spectra, (ii) optimized chemical design of molecular imaging probes for in vivo kinetics based on biology and physiology across a range of physical sizes, (iii) practical examples of second generation molecular imaging probes designed to extract complementary data from targets using multiple modalities, color, and comprehensive signals (277 references). PMID:21607237

  4. Manganese (II) Chelate Functionalized Copper Sulfide Nanoparticles for Efficient Magnetic Resonance/Photoacoustic Dual-Modal Imaging Guided Photothermal Therapy

    PubMed Central

    Liu, Renfa; Jing, Lijia; Peng, Dong; Li, Yong; Tian, Jie; Dai, Zhifei

    2015-01-01

    The integration of diagnostic and therapeutic functionalities into one nanoplatform shows great promise in cancer therapy. In this research, manganese (II) chelate functionalized copper sulfide nanoparticles were successfully prepared using a facile hydrothermal method. The obtained ultrasmall nanoparticles exhibit excellent photothermal effect and photoaoustic activity. Besides, the high loading content of Mn(II) chelates makes the nanoparticles attractive T1 contrast agent in magnetic resonance imaging (MRI). In vivo photoacoustic imaging (PAI) results showed that the nanoparticles could be efficiently accumulated in tumor site in 24 h after systematic administration, which was further validated by MRI tests. The subsequent photothermal therapy of cancer in vivo was achieved without inducing any observed side effects. Therefore, the copper sulfide nanoparticles functionalized with Mn(II) chelate hold great promise as a theranostic nanomedicine for MR/PA dual-modal imaging guided photothermal therapy of cancer. PMID:26284144

  5. Manganese (II) Chelate Functionalized Copper Sulfide Nanoparticles for Efficient Magnetic Resonance/Photoacoustic Dual-Modal Imaging Guided Photothermal Therapy.

    PubMed

    Liu, Renfa; Jing, Lijia; Peng, Dong; Li, Yong; Tian, Jie; Dai, Zhifei

    2015-01-01

    The integration of diagnostic and therapeutic functionalities into one nanoplatform shows great promise in cancer therapy. In this research, manganese (II) chelate functionalized copper sulfide nanoparticles were successfully prepared using a facile hydrothermal method. The obtained ultrasmall nanoparticles exhibit excellent photothermal effect and photoaoustic activity. Besides, the high loading content of Mn(II) chelates makes the nanoparticles attractive T1 contrast agent in magnetic resonance imaging (MRI). In vivo photoacoustic imaging (PAI) results showed that the nanoparticles could be efficiently accumulated in tumor site in 24 h after systematic administration, which was further validated by MRI tests. The subsequent photothermal therapy of cancer in vivo was achieved without inducing any observed side effects. Therefore, the copper sulfide nanoparticles functionalized with Mn(II) chelate hold great promise as a theranostic nanomedicine for MR/PA dual-modal imaging guided photothermal therapy of cancer.

  6. Differences in Multi-Modal Ultrasound Imaging between Triple Negative and Non-Triple Negative Breast Cancer.

    PubMed

    Li, Ziyao; Tian, Jiawei; Wang, Xiaowei; Wang, Ying; Wang, Zhenzhen; Zhang, Lei; Jing, Hui; Wu, Tong

    2016-04-01

    The objective of this study was to identify multi-modal ultrasound imaging parameters that could potentially help to differentiate between triple negative breast cancer (TNBC) and non-TNBC. Conventional ultrasonography, ultrasound strain elastography and 3-D ultrasound (3-D-US) findings from 50 TNBC and 179 non-TNBC patients were retrospectively reviewed. Immunohistochemical examination was used as the reference gold standard for cancer subtyping. Different ultrasound modalities were initially analyzed to define TNBC-related features. Subsequently, logistic regression analysis was applied to TNBC-related features to establish models for predicting TNBC. TNBCs often presented as micro-lobulated, markedly hypo-echoic masses with an abrupt interface (p = 0.015, 0.0015 and 0.004, compared with non-TNBCs, respectively) on conventional ultrasound, and showed a diminished retraction pattern phenomenon in the coronal plane (p = 0.035) on 3-D-US. Our findings suggest that B-mode ultrasound and 3-D-US in multi-modality ultrasonography could be a useful non-invasive technique for differentiating TNBCs from non-TNBCs.

  7. Real-time volume rendering visualization of dual-modality PET/CT images with interactive fuzzy thresholding segmentation.

    PubMed

    Kim, Jinman; Cai, Weidong; Eberl, Stefan; Feng, Dagan

    2007-03-01

    Three-dimensional (3-D) visualization has become an essential part for imaging applications, including image-guided surgery, radiotherapy planning, and computer-aided diagnosis. In the visualization of dual-modality positron emission tomography and computed tomography (PET/CT), 3-D volume rendering is often limited to rendering of a single image volume and by high computational demand. Furthermore, incorporation of segmentation in volume rendering is usually restricted to visualizing the presegmented volumes of interest. In this paper, we investigated the integration of interactive segmentation into real-time volume rendering of dual-modality PET/CT images. We present and validate a fuzzy thresholding segmentation technique based on fuzzy cluster analysis, which allows interactive and real-time optimization of the segmentation results. This technique is then incorporated into a real-time multi-volume rendering of PET/CT images. Our method allows a real-time fusion and interchangeability of segmentation volume with PET or CT volumes, as well as the usual fusion of PET/CT volumes. Volume manipulations such as window level adjustments and lookup table can be applied to individual volumes, which are then fused together in real time as adjustments are made. We demonstrate the benefit of our method in integrating segmentation with volume rendering in its application to PET/CT images. Responsive frame rates are achieved by utilizing a texture-based volume rendering algorithm and the rapid transfer capability of the high-memory bandwidth available in low-cost graphic hardware.

  8. Generation of Composite Dose and Biological Effective Dose (BED) Over Multiple Treatment Modalities and Multistage Planning Using Deformable Image Registration

    SciTech Connect

    Zhang, Geoffrey Huang, T-C; Feygelman, Vladimir; Stevens, Craig; Forster, Kenneth

    2010-07-01

    Currently there are no commercially available tools to generate composite plans across different treatment modalities and/or different planning image sets. Without a composite plan, it may be difficult to perform a meaningful dosimetric evaluation of the overall treatment course. In this paper, we introduce a method to generate composite biological effective dose (BED) plans over multiple radiotherapy treatment modalities and/or multistage plans, using deformable image registration. Two cases were used to demonstrate the method. Case I was prostate cancer treated with intensity-modulated radiation therapy (IMRT) and a permanent seed implant. Case II involved lung cancer treated with two treatment plans generated on two separate computed tomography image sets. Thin-plate spline or optical flow methods were used as appropriate to generate deformation matrices. The deformation matrices were then applied to the dose matrices and the resulting physical doses were converted to BED and added to yield the composite plan. Cell proliferation and sublethal repair were considered in the BED calculations. The difference in BED between normal tissues and tumor volumes was accounted for by using different BED models, {alpha}/{beta} values, and cell potential doubling times. The method to generate composite BED plans presented in this paper provides information not available with the traditional simple dose summation or physical dose summation. With the understanding of limitations and uncertainties of the algorithms involved, it may be valuable for the overall treatment plan evaluation.

  9. An efficient nano-based theranostic system for multi-modal imaging-guided photothermal sterilization in gastrointestinal tract.

    PubMed

    Liu, Zhen; Liu, Jianhua; Wang, Rui; Du, Yingda; Ren, Jinsong; Qu, Xiaogang

    2015-07-01

    Since understanding the healthy status of gastrointestinal tract (GI tract) is of vital importance, clinical implementation for GI tract-related disease have attracted much more attention along with the rapid development of modern medicine. Here, a multifunctional theranostic system combining X-rays/CT/photothermal/photoacoustic mapping of GI tract and imaging-guided photothermal anti-bacterial treatment is designed and constructed. PEGylated W18O49 nanosheets (PEG-W18O49) are created via a facile solvothermal method and an in situ probe-sonication approach. In terms of excellent colloidal stability, low cytotoxicity, and neglectable hemolysis of PEG-W18O49, we demonstrate the first example of high-performance four-modal imaging of GI tract by using these nanosheets as contrast agents. More importantly, due to their intrinsic absorption of NIR light, glutaraldehyde-modified PEG-W18O49 are successfully applied as fault-free targeted photothermal agents for imaging-guided killing of bacteria on a mouse infection model. Critical to pre-clinical and clinical prospects, long-term toxicity is further investigated after oral administration of these theranostic agents. These kinds of tungsten-based nanomaterials exhibit great potential as multi-modal contrast agents for directed visualization of GI tract and anti-bacterial agents for phothothermal sterilization.

  10. Biomimetic one-pot synthesis of gold nanoclusters/nanoparticles for targeted tumor cellular dual-modality imaging

    NASA Astrophysics Data System (ADS)

    Lin, Jing; Zhou, Zhijun; Li, Zhiming; Zhang, Chunlei; Wang, Xiansong; Wang, Kan; Gao, Guo; Huang, Peng; Cui, Daxiang

    2013-04-01

    Biomimetic synthesis has become a promising green pathway to prepare nanomaterials. In this study, bovine serum albumin (BSA)-conjugated gold nanoclusters/nanoparticles were successfully synthesized in water at room temperature by a protein-directed, solution-phase, green synthetic method. The synthesized BSA-Au nanocomplexes have fluorescence emission (588 nm) of gold nanoclusters and surface plasmon resonance of gold nanoparticles. The BSA-Au nanocomplexes display non-cytotoxicity and excellent biocompatibility on MGC803 gastric cancer cells. After conjugation of folic acid molecules, the obtained BSA-Au nanocomplexes showed highly selective targeting for MGC803 cells and dual-modality dark-field and fluorescence imaging.

  11. Feasibility of endoscopic laser speckle imaging modality in the evaluation of auditory disorder: study in bone-tissue phantom

    NASA Astrophysics Data System (ADS)

    Yu, Sungkon; Jang, Seulki; Lee, Sangyeob; Park, Jihoon; Ha, Myungjin; Radfar, Edalat; Jung, Byungjo

    2016-03-01

    This study investigates the feasibility of an endoscopic laser speckle imaging modality (ELSIM) in the measurement of perfusion of flowing fluid in optical bone tissue phantom(OBTP). Many studies suggested that the change of cochlear blood flow was correlated with auditory disorder. Cochlear microcirculation occurs under the 200μm thickness bone which is the part of the internal structure of the temporal bone. Concern has been raised regarding of getting correct optical signal from hard tissue. In order to determine the possibility of the measurement of cochlear blood flow under bone tissue using the ELSIM, optical tissue phantom (OTP) mimicking optical properties of temporal bone was applied.

  12. Automated method and system for the alignment and correlation of images from two different modalities

    DOEpatents

    Giger, Maryellen L.; Chen, Chin-Tu; Armato, Samuel; Doi, Kunio

    1999-10-26

    A method and system for the computerized registration of radionuclide images with radiographic images, including generating image data from radiographic and radionuclide images of the thorax. Techniques include contouring the lung regions in each type of chest image, scaling and registration of the contours based on location of lung apices, and superimposition after appropriate shifting of the images. Specific applications are given for the automated registration of radionuclide lungs scans with chest radiographs. The method in the example given yields a system that spatially registers and correlates digitized chest radiographs with V/Q scans in order to correlate V/Q functional information with the greater structural detail of chest radiographs. Final output could be the computer-determined contours from each type of image superimposed on any of the original images, or superimposition of the radionuclide image data, which contains high activity, onto the radiographic chest image.

  13. A new scheme for grading the quality of scientific reports that evaluate imaging modalities for cerebrovascular diseases.

    PubMed

    Qureshi, Adnan I

    2007-10-01

    Imaging of head and neck vasculature continues to improve with the application of new technology. To judge the value of new technologies reported in the literature, it is imperative to develop objective standards optimized against bias and favoring statistical power and clinical relevance. A review of the existing literature identified the following items as lending scientific value to a report on imaging technology: prospective design, comparison with an accepted modality, unbiased patient selection, standardized image acquisition, blinded interpretation, and measurement of reliability. These were incorporated into a new grading scheme. Two physicians tested the new scheme and an established scheme to grade reports published in the medical literature. Inter-observer reliability for both methods was calculated using the kappa coefficient. A total of 22 reports evaluating imaging modalities for cervical internal carotid artery stenosis were identified from a literature search and graded by both schemes. Agreement between the two physicians in grading the level of scientific evidence using the new scheme was excellent (kappa coefficient: 0.93, p<0.0001). Agreement using the established scheme was less rigorous (kappa coefficient: 0.39, p<0.0001). The weighted kappa coefficients were 0.95 and 0.38 for the new and established schemes, respectively. Overall agreement was higher for the newer scheme (95% versus 64%). The new grading scheme can be used reliably to categorize the strength of scientific knowledge provided by individual studies of vascular imaging. The new method could assist clinicians and researchers in determining appropriate clinical applications of newly reported technical advances.

  14. Active and Passive Optical Imaging Modality for Unobtrusive Cardiorespiratory Monitoring and Facial Expression Assessment.

    PubMed

    Blazek, Vladimir; Blanik, Nikolai; Blazek, Claudia R; Paul, Michael; Pereira, Carina; Koeny, Marcus; Venema, Boudewijn; Leonhardt, Steffen

    2017-01-01

    Because of their obvious advantages, active and passive optoelectronic sensor concepts are being investigated by biomedical research groups worldwide, particularly their camera-based variants. Such methods work noninvasively and contactless, and they provide spatially resolved parameter detection. We present 2 techniques: the active photoplethysmography imaging (PPGI) method for detecting dermal blood perfusion dynamics and the passive infrared thermography imaging (IRTI) method for detecting skin temperature distribution. PPGI is an enhancement of classical pulse oximetry. Approved algorithms from pulse oximetry for the detection of heart rate, heart rate variability, blood pressure-dependent pulse wave velocity, pulse waveform-related stress/pain indicators, respiration rate, respiratory variability, and vasomotional activity can easily be adapted to PPGI. Although the IRTI method primarily records temperature distribution of the observed object, information on respiration rate and respiratory variability can also be derived by analyzing temperature change over time, for example, in the nasal region, or through respiratory movement. Combined with current research areas and novel biomedical engineering applications (eg, telemedicine, tele-emergency, and telemedical diagnostics), PPGI and IRTI may offer new data for diagnostic purposes, including assessment of peripheral arterial and venous oxygen saturation (as well as their differences). Moreover, facial expressions and stress and/or pain-related variables can be derived, for example, during anesthesia, in the recovery room/intensive care unit and during daily activities. The main advantages of both monitoring methods are unobtrusive data acquisition and the possibility to assess vital variables for different body regions. These methods supplement each other to enable long-term monitoring of physiological effects and of effects with special local characteristics. They also offer diagnostic advantages for

  15. Magnetic/upconversion fluorescent NaGdF4:Yb,Er nanoparticle-based dual-modal molecular probes for imaging tiny tumors in vivo.

    PubMed

    Liu, Chunyan; Gao, Zhenyu; Zeng, Jianfeng; Hou, Yi; Fang, Fang; Li, Yilin; Qiao, Ruirui; Shen, Lin; Lei, Hao; Yang, Wensheng; Gao, Mingyuan

    2013-08-27

    Detection of early malignant tumors remains clinically difficult; developing ultrasensitive imaging agents is therefore highly demanded. Owing to the unusual magnetic and optical properties associated with f-electrons, rare-earth elements are very suitable for creating functional materials potentially useful for tumor imaging. Nanometer-sized particles offer such a platform with which versatile unique properties of the rare-earth elements can be integrated. Yet the development of rare-earth nanoparticle-based tumor probes suitable for imaging tiny tumors in vivo remains difficult, which challenges not only the physical properties of the nanoparticles but also the rationality of the probe design. Here we report new approaches for size control synthesis of magnetic/upconversion fluorescent NaGdF4:Yb,Er nanocrystals and their applications for imaging tiny tumors in vivo. By independently varying F(-):Ln(3+) and Na(+):Ln(3+) ratios, the size and shape regulation mechanisms were investigated. By replacing the oleic acid ligand with PEG2000 bearing a maleimide group at one end and two phosphate groups at the other end, PEGylated NaGdF4:Yb,Er nanoparticles with optimized size and upconversion fluorescence were obtained. Accordingly, a dual-modality molecular tumor probe was prepared, as a proof of concept, by covalently attaching antitumor antibody to PEGylated NaGdF4:Yb,Er nanoparticles through a "click" reaction. Systematic investigations on tumor detections, through magnetic resonance imaging and upconversion fluorescence imaging, were carried out to image intraperitoneal tumors and subcutaneous tumors in vivo. Owing to the excellent properties of the molecular probes, tumors smaller than 2 mm was successfully imaged in vivo. In addition, pharmacokinetic studies on differently sized particles were performed to disclose the particle size dependent biodistributions and elimination pathways.

  16. Activatable albumin-photosensitizer nanoassemblies for triple-modal imaging and thermal-modulated photodynamic therapy of cancer.

    PubMed

    Hu, Dehong; Sheng, Zonghai; Gao, Guanhui; Siu, Fungming; Liu, Chengbo; Wan, Qian; Gong, Ping; Zheng, Hairong; Ma, Yifan; Cai, Lintao

    2016-07-01

    Photodynamic therapy (PDT) is a noninvasive and effective approach for cancer treatment. The main bottlenecks of clinical PDT are poor selectivity of photosensitizer and inadequate oxygen supply resulting in serious side effects and low therapeutic efficiency. Herein, a thermal-modulated reactive oxygen species (ROS) strategy using activatable human serum albumin-chlorin e6 nanoassemblies (HSA-Ce6 NAs) for promoting PDT against cancer is developed. Through intermolecular disulfide bond crosslinking and hydrophobic interaction, Ce6 photosensitizer is effectively loaded into the HSA NAs, and the obtained HSA-Ce6 NAs exhibit excellent reduction response, as well as enhanced tumor accumulation and retention. By the precision control of the overall body temperature instead of local tumor temperature increasing from 37 °C to 43 °C, the photosensitization reaction rate of HSA-Ce6 NAs increases 20%, and the oxygen saturation of tumor tissue raise 52%, significantly enhancing the generation of ROS for promoting PDT. Meanwhile, the intrinsic fluorescence and photoacoustic properties, and the chelating characteristic of porphyrin ring can endow the HSA-Ce6 NAs with fluorescence, photoacoustic and magnetic resonance triple-modal imaging functions. Upon irradiation of low-energy near-infrared laser, the tumors are completely suppressed without tumor recurrence and therapy-induced side effects. The robust thermal-modulated ROS strategy combined with albumin-based activatable nanophotosensitizer is highly potential for multi-modal imaging-guided PDT and clinical translation.

  17. Biodegradable yolk-shell microspheres for ultrasound/MR dual-modality imaging and controlled drug delivery.

    PubMed

    Yang, Peng; Luo, Xianfu; Wang, Sheng; Wang, Fang; Tang, Chuanbing; Wang, Changchun

    2017-03-01

    A new class of uniform biodegradable yolk-shell Fe3O4@PFH@PMAA-DOX microspheres was developed as ultrasound/MR dual-modality imaging contrast agents and drug delivery system. PMAA shells exhibit excellent drug loading capability and efficiency, the DOX-loading capacity is 15.4wt% and the drug loading efficiency is 91%. In vivo ultrasound and MRI experiments indicate that the as-prepared Fe3O4@PFH@PMAA-DOX microspheres successfully reach tumor tissues and possess robust dual-modality imaging capability, the r2 value of MRI is 71.82mM(-1)s(-1). In vitro cytotoxicity and in vivo tissues biopsies show that the loaded DOX can be control-released under pH, redox and ultrasound multi-stimuli and kill cancer cells effectively. Furthermore, disulfide-crosslinked PMAA shells and PGA-stabilized Fe3O4 cores can be respectively degraded into short hydrophilic polymer chains and iron ions, reducing their cumulative toxicity in organisms. Thus, the multifunctional biodegradable microspheres are safer for normal tissues and more beneficial in actual clinical applications.

  18. Quantitative phase-digital holographic microscopy: a new imaging modality to identify original cellular biomarkers of diseases

    NASA Astrophysics Data System (ADS)

    Marquet, P.; Rothenfusser, K.; Rappaz, B.; Depeursinge, C.; Jourdain, P.; Magistretti, P. J.

    2016-03-01

    Quantitative phase microscopy (QPM) has recently emerged as a powerful label-free technique in the field of living cell imaging allowing to non-invasively measure with a nanometric axial sensitivity cell structure and dynamics. Since the phase retardation of a light wave when transmitted through the observed cells, namely the quantitative phase signal (QPS), is sensitive to both cellular thickness and intracellular refractive index related to the cellular content, its accurate analysis allows to derive various cell parameters and monitor specific cell processes, which are very likely to identify new cell biomarkers. Specifically, quantitative phase-digital holographic microscopy (QP-DHM), thanks to its numerical flexibility facilitating parallelization and automation processes, represents an appealing imaging modality to both identify original cellular biomarkers of diseases as well to explore the underlying pathophysiological processes.

  19. Reliability of whole slide images as a diagnostic modality for renal allograft biopsies.

    PubMed

    Jen, Kuang-Yu; Olson, Jean L; Brodsky, Sergey; Zhou, Xin J; Nadasdy, Tibor; Laszik, Zoltan G

    2013-05-01

    The use of digital whole slide images (WSI) in the field of pathology has become feasible for routine diagnostic purposes and has become more prevalent in recent years. This type of technology offers many advantages but must show the same degree of diagnostic reliability as conventional glass slides. Several studies have examined this issue in various settings and indicate that WSI are a reliable method for diagnostic pathology. Since transplant pathology is a highly specialized field that requires not only accurate but rapid diagnostic evaluation of biopsy materials, this field may greatly benefit from the use of WSI. In this study, we assessed the reliability of using WSI compared to conventional glass slides in renal allograft biopsies. We examined morphologic features and diagnostic categories defined by the Banff 07 Classification of Renal Allograft Pathology as well as additional morphologic features not included in this classification scheme. We found that intraobserver scores, when comparing the use of glass slides versus WSI, showed substantial agreement for both morphologic features (κ = 0.68) and acute rejection diagnostic categories (κ = 0.74). Furthermore, interobserver reliability was comparable for morphologic features (κ = 0.44 [glass] vs 0.42 [WSI]) and acute rejection diagnostic categories (κ = 0.49 [glass] vs 0.51 [WSI]). These data indicate that WSI are as reliable as glass slides for the evaluation of renal allograft biopsies.

  20. A review of functional pelvic floor imaging modalities and their effectiveness.

    PubMed

    Ahmad, Aminah N; Hainsworth, Alison; Williams, Andrew B; Schizas, Alexis M P

    2015-01-01

    The anatomy of the pelvic floor is complex and clinical examination alone is often insufficient to diagnose and assess pathology. With a greater understanding of pelvic floor dysfunction and treatment options, imaging is becoming increasingly common. This review compares three imaging techniques. Ultrasound has the potential for dynamic assessment of the entire pelvic floor. Magnetic resonance imaging is able to rapidly image the entire pelvic floor but it is expensive and tends to underestimate pathology. Dynamic defaecating proctography or cystocolpoproctography is the current gold standard for posterior compartment imaging but requires opacification of the bladder to provide a global view.

  1. Co-registration of multi-modality imaging allows for comprehensive analysis of tumor-induced bone disease

    PubMed Central

    Seeley, Erin H.; Wilson, Kevin J.; Yankeelov, Thomas E.; Johnson, Rachelle W.; Gore, John C.; Caprioli, Richard M.; Matrisian, Lynn M.; Sterling, Julie A.

    2014-01-01

    Bone metastases are a clinically significant problem that arises in approximately 70% of metastatic breast cancer patients. Once established in bone, tumor cells induce changes in the bone microenvironment that lead to bone destruction, pain, and significant morbidity. While much is known about the later stages of bone disease, less is known about the earlier stages or the changes in protein expression in the tumor micro-environment. Due to promising results of combining magnetic resonance imaging (MRI) and Matrix-Assisted Laser Desorption/Ionization Imaging Mass Spectrometry (MALDI IMS) ion images in the brain, we developed methods for applying these modalities to models of tumor-induced bone disease in order to better understand the changes in protein expression that occur within the tumor-bone microenvironment. Specifically, we integrated three dimensional-volume reconstructions of spatially resolved MALDI IMS with high-resolution anatomical and diffusion weighted MRI data and histology in an intratibial model of breast tumor-induced bone disease. This approach enables us to analyze proteomic profiles from MALDI IMS data with corresponding in vivo imaging and ex vivo histology data. To the best of our knowledge, this is the first time these three modalities have been rigorously registered in the bone. The MALDI mass-to-charge ratio peaks indicate differential expression of calcyclin, ubiquitin, and other proteins within the tumor cells, while peaks corresponding to hemoglobin A and calgranulin A provided molecular information that aided in the identification of areas rich in red and white blood cells, respectively. This multimodality approach will allow us to comprehensively understand the bone-tumor microenvironment and thus may allow us to better develop and test approaches for inhibiting bone metastases. PMID:24487126

  2. Terahertz imaging modalities of ancient Egyptian mummified objects and of a naturally mummified rat.

    PubMed

    Öhrström, Lena; Fischer, Bernd M; Bitzer, Andreas; Wallauer, Jan; Walther, Markus; Rühli, Frank

    2015-06-01

    During the last few years, terahertz (THz) imaging has been used to investigate artwork and historic artifacts. The application of THz imaging to mummy investigations is very attractive since it provides spectroscopic information over a broad frequency range and its radiation has proven to be harmless to human cells. However, compared with the current standard imaging methods in mummy imaging-X-ray and computed tomography (CT)--it remains a novel, emerging technique whose potential still needs to be fully evaluated. Here, ancient Egyptian mummified objects as well as a naturally mummified rat have been investigated by two different THz imaging systems: a broadband THz time domain imaging system and an electronic THz scanner. The obtained THz images are compared with conventional CT, X-ray, and magnetic resonance images. While the broadband THz time domain setup permits analyses of smaller samples, the electronic THz scanner allows the recording of data of thicker and larger samples at the expense of a limited spectral bandwidth. Terahertz imaging shows clear potential for mummy investigations, although currently CT imaging offers much higher spatial resolution. Furthermore, as commercial mobile THz scanners become available, THz imaging could be applied directly in museums or at excavation sites.

  3. Rapamycin/DiR loaded lipid-polyaniline nanoparticles for dual-modal imaging guided enhanced photothermal and antiangiogenic combination therapy.

    PubMed

    Wang, Jinping; Guo, Fang; Yu, Meng; Liu, Li; Tan, Fengping; Yan, Ran; Li, Nan

    2016-09-10

    Imaging-guided photothermal therapy (PTT) has promising application for treating tumors. Nevertheless, so far imaging-guided photothermal drug-delivery systems have been developed with limited success for tumor chemo-photothermal therapy. In this study, as the proof-of-concept, a stimuli-responsive tumor-targeting rapamycin/DiR loaded lipid-polyaniline nanoparticle (RDLPNP) for dual-modal imaging-guided enhanced PTT efficacy is reported for the first time. In this system, polyaniline (PANI) with π-π electronic conjugated system and effective photothermal efficiency is chosen as the appropriate model receptor of fluorescence resonance energy transfer (FRET), and loaded cyanine probe (e.g., 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyanine iodide, DiR) acts as the donor of near-infrared fluorescence (NIRF). In addition, rapamycin (RAPA), which is used as the antiangiogenesis chemotherapeutic drug, can cutdown the tumor vessels and delay tumor growth obviously. After intravenous treatment of RDLPNPs into Hela tumor bearing mice, fluorescent (from DiR) and enhanced photoacoustic (from DLPNPs) signals were found in tumor site over time, which reached to peak at the 6h time point. After irradiating with an NIR laser, a good anti-tumor effect was observed owing to the enhanced photothermal and antiangiogenic effect of RDLPNPs. These results show that the multifunctional nanoparticle can be used as a promising imaging-guided photothermal drug delivery nanoplatform for cancer therapy.

  4. Crossed Cerebellar Diaschisis: Three Case Reports Imaging Using a Tri-Modality PET/CT-MR System.

    PubMed

    Han, Shuguang; Wang, Xiaopeng; Xu, Kai; Hu, Chunfeng

    2016-01-01

    Crossed cerebellar diaschisis (CCD) describes a depression of oxidative metabolism glucose and blood flow in the cerebellum secondary to a supratentorial lesion in the contralateral cerebral hemisphere. PET/MR has the potential to become a powerful tool for demonstrating and imaging intracranial lesions .We herein report 3 cases of CCD imaging using a tri-modality PET/CT-MR set-up for investigating the value of adding MRI rather than CT to PET in clinical routine.We describe 3 patients with CCD and neurological symptoms in conjunction with abnormal cerebral fluorodeoxyglucose (FDG) positron emission tomography/computed tomography-magnetic resonance imaging (PET/CT-MR) manifestations including arterial spin-labeling (ASL) and T2-weighted images. In all, 18FDG-PET/CT detected positive FDG uptake in supratentorial lesions, and hypometabolism with atrophy in the contralateral cerebellum. More than that, hybrid PET/MRI provided a more accurate anatomic localization and ASL indicated disruption of the cortico-ponto-cerebellar pathway.Using pathology or long-term clinical follow-up to confirm the PET and ASL findings, the supratentorial lesions of the 3 patients were respectively diagnosed with cerebral infarction, recurrent glioma, and metastasis.The reports emphasize the significance of multimodality radiological examinations. Multimodality imaging contributes to proper diagnosis, management, and follow-up of supratentorial lesions with CCD.

  5. A dual-modality photoacoustic and ultrasound imaging system for noninvasive sentinel lymph node detection: preliminary clinical results

    NASA Astrophysics Data System (ADS)

    Erpelding, Todd N.; Garcia-Uribe, Alejandro; Krumholz, Arie; Ke, Haixin; Maslov, Konstantin; Appleton, Catherine; Margenthaler, Julie; Wang, Lihong V.

    2014-03-01

    Sentinel lymph node biopsy (SLNB) has emerged as an accurate, less invasive alternative to axillary lymph node dissection, and it has rapidly become the standard of care for patients with clinically node-negative breast cancer. The sentinel lymph node (SLN) hypothesis states that the pathological status of the axilla can be accurately predicted by determining the status of the first (i.e., sentinel) lymph nodes that drain from the primary tumor. Physicians use radio-labeled sulfur colloid and/or methylene blue dye to identify the SLN, which is most likely to contain metastatic cancer cells. However, the surgical procedure causes morbidity and associated expenses. To overcome these limitations, we developed a dual-modality photoacoustic and ultrasound imaging system to noninvasively detect SLNs based on the accumulation of methylene blue dye. Ultimately, we aim to guide percutaneous needle biopsies and provide a minimally invasive method for axillary staging of breast cancer. The system consists of a tunable dye laser pumped by a Nd:YAG laser, a commercial ultrasound imaging system (Philips iU22), and a multichannel data acquisition system which displays co-registered photoacoustic and ultrasound images in real-time. Our clinical results demonstrate that real-time photoacoustic imaging can provide sensitive and specific detection of methylene blue dye in vivo. While preliminary studies have shown that in vivo detection of SLNs by using co-registered photoacoustic and ultrasound imaging is feasible, further investigation is needed to demonstrate robust SLN detection.

  6. Folic acid-conjugated GdPO4:Tb3+@SiO2 Nanoprobe for folate receptor-targeted optical and magnetic resonance bi-modal imaging

    NASA Astrophysics Data System (ADS)

    Xu, Xianzhu; Zhang, Xiaoying; Wu, Yanli

    2016-11-01

    Both fluorescent and magnetic nanoprobes have great potential applications for diagnostics and therapy. In the present work, a folic acid-conjugated and silica-modified GdPO4:Tb3+ (GdPO4:Tb3+@SiO2-FA) dual nanoprobe was strategically designed and synthesized for the targeted dual-modality optical and magnetic resonance (MR) imaging via a facile aqueous method. Their structural, optical, and magnetic properties were determined using transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), ultraviolet-visible spectra (UV-Vis), photoluminescence (PL), and superconducting quantum interference device (SQUID). These results indicated that GdPO4:Tb3+@SiO2-FA were uniform monodisperse core-shell structured nanorods (NRs) with an average length of 200 nm and an average width of 25 nm. The paramagnetic property of the synthesized GdPO4:Tb3+@SiO2-FA NRs was confirmed with its linear hysteresis plot (M-H). In addition, the NRs displayed an obvious T1-weighted effect and thus it could potentially serve as a T1-positive contrast agent. The NRs emitted green lights due to the 5D4 → 7F5 transition of the Tb3+. The in vitro assays with NCI-H460 lung cancer cells and human embryonic kidney cell line 293T cells indicated that the GdPO4:Tb3+@SiO2-FA nanoprobe could specifically bind the cells bearing folate receptors (FR). The MTT assay of the NRs revealed that its cytotoxicity was very low. Further in vivo MRI experiments distinctively depict enhanced anatomical features in a xenograft tumor. These results suggest that the GdPO4:Tb3+@SiO2-FA NPs have excellent imaging and cell-targeting abilities for the folate receptor-targeted dual-modality optical and MR imaging and can be potentially used as the nanoprobe for bioimaging.

  7. Imaging of Tissue Micro-Structures using a Multi-Modal Microscope Design

    SciTech Connect

    Demos, S G; Lieber, C A; Lin, B; Ramsamooj, R

    2005-08-12

    We investigate a microscope design that offers high signal sensitivity and hyperspectral imaging capabilities and allows for implementation of various optical imaging approaches while its operational complexity is minimized. This system utilizes long working distance microscope objectives that enable for off-axis illumination of the tissue thereby allowing for excitation at any optical wavelength and nearly eliminating spectral noise from the optical elements. Preliminary studies using human and animal tissues demonstrate the feasibility of this approach for real-time imaging of intact tissue microstructures using autofluorescence and light scattering imaging methods.

  8. Dual-modality, fluorescent, PLGA encapsulated bismuth nanoparticles for molecular and cellular fluorescence imaging and computed tomography

    NASA Astrophysics Data System (ADS)

    Swy, Eric R.; Schwartz-Duval, Aaron S.; Shuboni, Dorela D.; Latourette, Matthew T.; Mallet, Christiane L.; Parys, Maciej; Cormode, David P.; Shapiro, Erik M.

    2014-10-01

    Reports of molecular and cellular imaging using computed tomography (CT) are rapidly increasing. Many of these reports use gold nanoparticles. Bismuth has similar CT contrast properties to gold while being approximately 1000-fold less expensive. Herein we report the design, fabrication, characterization, and CT and fluorescence imaging properties of a novel, dual modality, fluorescent, polymer encapsulated bismuth nanoparticle construct for computed tomography and fluorescence imaging. We also report on cellular internalization and preliminary in vitro and in vivo toxicity effects of these constructs. 40 nm bismuth(0) nanocrystals were synthesized and encapsulated within 120 nm Poly(dl-lactic-co-glycolic acid) (PLGA) nanoparticles by oil-in-water emulsion methodologies. Coumarin-6 was co-encapsulated to impart fluorescence. High encapsulation efficiency was achieved ~70% bismuth w/w. Particles were shown to internalize within cells following incubation in culture. Bismuth nanocrystals and PLGA encapsulated bismuth nanoparticles exhibited >90% and >70% degradation, respectively, within 24 hours in acidic, lysosomal environment mimicking media and both remained nearly 100% stable in cytosolic/extracellular fluid mimicking media. μCT and clinical CT imaging was performed at multiple X-ray tube voltages to measure concentration dependent attenuation rates as well as to establish the ability to detect the nanoparticles in an ex vivo biological sample. Dual fluorescence and CT imaging is demonstrated as well. In vivo toxicity studies in rats revealed neither clinically apparent side effects nor major alterations in serum chemistry and hematology parameters. Calculations on minimal detection requirements for in vivo targeted imaging using these nanoparticles are presented. Indeed, our results indicate that these nanoparticles may serve as a platform for sensitive and specific targeted molecular CT and fluorescence imaging.Reports of molecular and cellular imaging using

  9. An automated robot arm system for small animal tissue biopsy under dual-image modality

    NASA Astrophysics Data System (ADS)

    Huang, Y. H.; Wu, T. H.; Lin, M. H.; Yang, C. C.; Guo, W. Y.; Wang, Z. J.; Chen, C. L.; Lee, J. S.

    2006-12-01

    The ability to non-invasively monitor cell biology in vivo is one of the most important goals of molecular imaging. Imaging procedures could be inter-subject performed repeatedly at different investigating stages; thereby need not sacrifice small animals during the entire study period. Thus, the ultimate goal of this study was to design a stereotactic image-guided system for small animals and integrated it with an automatic robot arm for in vivo tissue biopsy analysis. The system was composed of three main parts, including one small animal stereotactic frame, one imaging-fusion software and an automatic robot arm system. The system has been thoroughly evaluated with three components; the robot position accuracy was 0.05±0.02 mm, the image registration accuracy was 0.37±0.18 mm and the system integration was satisfactorily within 1.20±0.39 mm of error. From these results, the system demonstrated sufficient accuracy to guide the micro-injector from the planned delivery routes into practice. The entire system accuracy was limited by the image fusion and orientation procedures, due to its nature of the blurred PET imaging obtained from the small objects. The primary improvement is to acquire as higher resolution as possible the fused imaging for localizing the targets in the future.

  10. Dual-modality, fluorescent, PLGA encapsulated bismuth nanoparticles for molecular and cellular fluorescence imaging and computed tomography.

    PubMed

    Swy, Eric R; Schwartz-Duval, Aaron S; Shuboni, Dorela D; Latourette, Matthew T; Mallet, Christiane L; Parys, Maciej; Cormode, David P; Shapiro, Erik M

    2014-11-07

    Reports of molecular and cellular imaging using computed tomography (CT) are rapidly increasing. Many of these reports use gold nanoparticles. Bismuth has similar CT contrast properties to gold while being approximately 1000-fold less expensive. Herein we report the design, fabrication, characterization, and CT and fluorescence imaging properties of a novel, dual modality, fluorescent, polymer encapsulated bismuth nanoparticle construct for computed tomography and fluorescence imaging. We also report on cellular internalization and preliminary in vitro and in vivo toxicity effects of these constructs. 40 nm bismuth(0) nanocrystals were synthesized and encapsulated within 120 nm Poly(dl-lactic-co-glycolic acid) (PLGA) nanoparticles by oil-in-water emulsion methodologies. Coumarin-6 was co-encapsulated to impart fluorescence. High encapsulation efficiency was achieved ∼70% bismuth w/w. Particles were shown to internalize within cells following incubation in culture. Bismuth nanocrystals and PLGA encapsulated bismuth nanoparticles exhibited >90% and >70% degradation, respectively, within 24 hours in acidic, lysosomal environment mimicking media and both remained nearly 100% stable in cytosolic/extracellular fluid mimicking media. μCT and clinical CT imaging was performed at multiple X-ray tube voltages to measure concentration dependent attenuation rates as well as to establish the ability to detect the nanoparticles in an ex vivo biological sample. Dual fluorescence and CT imaging is demonstrated as well. In vivo toxicity studies in rats revealed neither clinically apparent side effects nor major alterations in serum chemistry and hematology parameters. Calculations on minimal detection requirements for in vivo targeted imaging using these nanoparticles are presented. Indeed, our results indicate that these nanoparticles may serve as a platform for sensitive and specific targeted molecular CT and fluorescence imaging.

  11. In vivo MR and Fluorescence Dual-modality Imaging of Atherosclerosis Characteristics in Mice Using Profilin-1 Targeted Magnetic Nanoparticles

    PubMed Central

    Wang, Yabin; Chen, Jiangwei; Yang, Bo; Qiao, Hongyu; Gao, Lei; Su, Tao; Ma, Sai; Zhang, Xiaotian; Li, Xiujuan; Liu, Gang; Cao, Jianbo; Chen, Xiaoyuan; Chen, Yundai; Cao, Feng

    2016-01-01

    Aims: This study aims to explore non-invasive imaging of atherosclerotic plaque through magnetic resonance imaging (MRI) and near-infrared fluorescence (NIRF) by using profilin-1 targeted magnetic iron oxide nanoparticles (PF1-Cy5.5-DMSA-Fe3O4-NPs, denoted as PC-NPs) as multimodality molecular imaging probe in murine model of atherosclerosis. Methods and Results: PC-NPs were constructed by conjugating polyclonal profilin-1 antibody and NHS-Cy5.5 fluorescent dye to the surface of DMSA-Fe3O4-nanoparticles via condensation reaction. Murine atherosclerosis model was induced in apoE-/- mice by high fat and cholesterol diet (HFD) for 16 weeks. The plaque areas in aortic artery were detected with Oil Red O staining. Immunofluorescent staining and Western blot analysis were applied respectively to investigate profilin-1 expression. CCK-8 assay and transwell migration experiment were performed to detect vascular smooth muscle cells (VSMCs) proliferation. In vivo MRI and NIRF imaging of atherosclerotic plaque were carried out before and 36 h after intravenous injection of PC-NPs. Oil Red O staining showed that the plaque area was significantly increased in HFD group (p<0.05). Immunofluorescence staining revealed that profilin-1 protein was highly abundant within plaque in HFD group and co-localized with α-smooth muscle actin. Profilin-1 siRNA intervention could inhibit VSMCs proliferation and migration elicited by ox-LDL (p<0.05). In vivo MRI and NIRF imaging revealed that PC-NPs accumulated in atherosclerotic plaque of carotid artery. There was a good correlation between the signals of MRI and ex vivo fluorescence intensities of NIRF imaging in animals with PC-NPs injection. Conclusion: PC-NPs is a promising dual modality imaging probe, which may improve molecular diagnosis of plaque characteristics and evaluation of pharmaceutical interventions for atherosclerosis. PMID:26877785

  12. Dual-modality, fluorescent, PLGA encapsulated bismuth nanoparticles for molecular and cellular fluorescence imaging and computed tomography

    PubMed Central

    Swy, Eric R.; Schwartz-Duval, Aaron S.; Shuboni, Dorela D.; Latourette, Matthew T.; Mallet, Christiane L.; Parys, Maciej; Cormode, David P.; Shapiro, Erik M.

    2015-01-01

    Reports of molecular and cellular imaging using computed tomography (CT) are rapidly increasing. Many of these reports use gold nanoparticles. Bismuth has similar CT contrast properties to gold while being approximately 1000-fold less expensive. Herein we report the design, fabrication, characterization, and CT and fluorescence imaging properties of a novel, dual modality, fluorescent, polymer encapsulated bismuth nanoparticle construct for computed tomography and fluorescence imaging. We also report on cellular internalization and preliminary in vitro and in vivo toxicity effects of these constructs. 40 nm bismuth(0) nanocrystals were synthesized and encapsulated within 120 nm Poly(DL-lactic-co-glycolic acid) (PLGA) nanoparticles by oil-in-water emulsion methodologies. Coumarin-6 was co-encapsulated to impart fluorescence. High encapsulation efficiency was achieved ∼ 70% bismuth w/w. Particles were shown to internalize within cells following incubation in culture. Bismuth nanocrystals and PLGA encapsulated bismuth nanoparticles exhibited >90% and >70% degradation, respectively, within 24 hours in acidic, lysosomal environment mimicking media and both remained nearly 100% stable in cytosolic/extracellular fluid mimicking media. μCT and clinical CT imaging was performed at multiple X-ray tube voltages to measure concentration dependent attenuation rates as well as to establish the ability to detect the nanoparticles in an ex vivo biological sample. Dual fluorescence and CT imaging is demonstrated as well. In vivo toxicity studies in rats revealed neither clinically apparent side effects nor major alterations in serum chemistry and hematology parameters. Calculations on minimal detection requirements for in vivo targeted imaging using these nanoparticles are presented. Indeed, our results indicate that these nanoparticles may serve as a platform for sensitive and specific targeted molecular CT and fluorescence imaging. PMID:25248645

  13. SU-E-I-84: Accuracy Comparison of Multi-Modality Image-Based Volumes of Rodent Solid Tumors Using In-Air Micro-CT Image Volume

    SciTech Connect

    Lee, Y; Fullerton, G; Goins, B

    2015-06-15

    Purpose: Tumor volume is considered as a better predictor for therapy response monitoring and tumor staging over Response Evaluation Criteria In Solid Tumors (RECIST) or World Health Organization (WHO) criteria. In this study, the accuracy of subcutaneous rodent tumor volumes using preclinical magnetic resonance imaging (MRI), micro-computed tomography (micro-CT) and ultrasound (US) equipment and with an external caliper was compared using in-air micro-CT image volume of excised tumors determined as reference tumor volume in our prior study. Methods: MR, US and micro-CT images of subcutaneous SCC4 head and neck tumor xenografts were acquired 4, 6, 9, 11 and 13 days after tumor cell inoculation. Before MR and US scans, caliper measurements were made. After tumors were excised, in-air micro-CT imaging and ex vivo caliper measurements were performed. Tumor volumes were calculated using formula V = (π/6)*a*b*c where a, b and c are the maximum diameters in three perpendicular dimensions determined by the three image modalities and caliper, and compared with reference tumor volume by linear regression analysis as well as Bland-Altman plots. A one-way Analysis of Variance (ANOVA) test was also performed to compare volumes among caliper measurements. Results: The correlation coefficients (R2) of the regression lines for tumor volumes measured by the three imaging modalities and caliper were 0.9939, 0.9669, 0.9806, 0.9274, 0.9619 and 0.9819 for MRI, US and micro-CT, caliperbeforeMRI, caliperbeforeUS and ex vivo caliper respectively. In Bland-Altman plots, the average of tumor volume difference from reference tumor volume (bias) was significant for caliper and micro- CT, but not for MRI and US. Comparison of caliper measurements showed a significant difference (p < 0.05). Conclusion: Using the in-air micro-CT image volume, tumor volume measured by MRI was the most accurate among the three imaging modalities. In vivo caliper volume measurements showed unreliability while ex

  14. Upconverting rare-earth nanoparticles with a paramagnetic lanthanide complex shell for upconversion fluorescent and magnetic resonance dual-modality imaging

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Ji, Lei; Zhang, Bingbo; Yin, Peihao; Qiu, Yanyan; Song, Daqian; Zhou, Juying; Li, Qi

    2013-05-01

    Multi-modal imaging based on multifunctional nanoparticles is a promising alternative approach to improve the sensitivity of early cancer diagnosis. In this study, highly upconverting fluorescence and strong relaxivity rare-earth nanoparticles coated with paramagnetic lanthanide complex shells and polyethylene glycol (PEGylated UCNPs@DTPA-Gd3+) are synthesized as dual-modality imaging contrast agents (CAs) for upconverting fluorescent and magnetic resonance dual-modality imaging. PEGylated UCNPs@DTPA-Gd3+ with sizes in the range of 32-86 nm are colloidally stable. They exhibit higher longitudinal relaxivity and transverse relaxivity in water (r1 and r2 values are 7.4 and 27.8 s-1 per mM Gd3+, respectively) than does commercial Gd-DTPA (r1 and r2 values of 3.7 and 4.6 s-1 per mM Gd3+, respectively). They are found to be biocompatible. In vitro cancer cell imaging shows good imaging contrast of PEGylated UCNPs@DTPA-Gd3+. In vivo upconversion fluorescent imaging and T1-weighted MRI show excellent enhancement of both fluorescent and MR signals in the livers of mice administered PEGylated UCNPs@DTPA-Gd3+. All the experimental results indicate that the synthesized PEGylated UCNPs@DTPA-Gd3+ present great potential for biomedical upconversion of fluorescent and magnetic resonance dual-modality imaging applications.

  15. Dual-modal MRI contrast agent with aggregation-induced emission characteristic for liver specific imaging with long circulation lifetime.

    PubMed

    Chen, Yilong; Li, Min; Hong, Yuning; Lam, Jacky W Y; Zheng, Qichang; Tang, Ben Zhong

    2014-07-09

    We herein report a novel dual-modal MRI contrast agent, TPE-2Gd, for both magnetic and fluorescence imaging. TPE-2Gd consists of a hydrophobic tetraphenylethene (TPE) fluorophore and two hydrophilic gadolinium (Gd) diethylenetriaminepentaacetic acid moieties. As an amphiphilic molecule, TPE-2Gd aggregates into micelles at a high concentration in aqueous medium. These aggregates are highly emissive, showing an aggregation-induced emission (AIE) characteristic. TPE-2Gd is used as a fluorescent agent for cell imaging, which demonstrates negligible cytotoxicity and excellent photostability owing to its AIE property. As a magnetic resonance imaging (MRI) contrast agent, TPE-2Gd exhibits similar longitudinal relaxivity in water (R1,TPE-2Gd = 3.36 ± 0.10 s(-1) per mM of Gd(3+)) as those commercial agents (e.g., Magnevist, R1,magnevist = 3.70 ± 0.02 s(-1) per mM of Gd(3+)). Compared with Magnevist, the circulation lifetime of TPE-2Gd nanoaggregates in living rats is extended from 10 min to 1 h. With relatively high specificity to the liver, the MR imaging could remain hyperintense in liver even after 150 min post injection. These TPE-2Gd nanoparticles can be excreted gradually via renal filtration due to the disassembly of the nanoparticles into small molecules during circulation. TPE-2Gd could thus potentially be used as a liver specific MRI contrast agent for clinical diagnosis.

  16. A review of consensus test methods for established medical imaging modalities and their implications for optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Pfefer, Joshua; Agrawal, Anant

    2012-03-01

    In recent years there has been increasing interest in development of consensus, tissue-phantom-based approaches for assessment of biophotonic imaging systems, with the primary goal of facilitating clinical translation of novel optical technologies. Well-characterized test methods based on tissue phantoms can provide useful tools for performance assessment, thus enabling standardization and device inter-comparison during preclinical development as well as quality assurance and re-calibration in the clinical setting. In this review, we study the role of phantom-based test methods as described in consensus documents such as international standards for established imaging modalities including X-ray CT, MRI and ultrasound. Specifically, we focus on three image quality characteristics - spatial resolution, spatial measurement accuracy and image uniformity - and summarize the terminology, metrics, phantom design/construction approaches and measurement/analysis procedures used to assess these characteristics. Phantom approaches described are those in routine clinical use and tend to have simplified morphology and biologically-relevant physical parameters. Finally, we discuss the potential for applying knowledge gained from existing consensus documents in the development of standardized, phantom-based test methods for optical coherence tomography.

  17. Multi-modal in vivo imaging of brain blood oxygenation, blood flow and neural calcium dynamics during acute seizures

    NASA Astrophysics Data System (ADS)

    Ringuette, Dene; Jeffrey, Melanie A.; Carlen, Peter L.; Levi, Ofer

    2016-03-01

    Dysfunction of the vascular endothelium has been implicated in the development of epilepsy. To better understand the relation between vascular function and seizure and provide a foundation for interpreting results from functional imaging in chronic disease models, we investigate the relationship between intracellular calcium dynamics and local cerebral blood flow and blood oxygen saturation during acute seizure-like events and pharmacological seizure rescue. To probe the relation between the aforementioned physiological markers in an acute model of epilepsy in rats, we integrated three different optical modalities together with electrophysiological recordings: Laser speckle contrast imaging (LSCI) was used to study changes in flow speeds, Intrinsic optical signal imaging (IOSI) was used to monitor changes in oxygenated, de-oxygenated, and total hemoglobin concentration, and Calcium-sensitive dye imaging was used to monitor intracellular calcium dynamics. We designed a dedicated cortical flow chamber to remove superficial blood and dye resulting from the injection procedure, which reduced spurious artifacts. The near infrared light used for IOSI and LSCI was delivered via a light pipe integrated with the flow chamber to minimize the effect of fluid surface movement on illumination stability. Calcium-sensitive dye was injected via a glass electrode used for recording the local field potential. Our system allowed us to observe and correlate increases in intracellular calcium, blood flow and blood volume during seizure-like events and provide a quantitative analysis of neurovascular coupling changes associated with seizure rescue via injection of an anti-convulsive agent.

  18. Principles of nuclear medicine imaging: planar, SPECT, PET, multi-modality, and autoradiography systems.

    PubMed

    Zanzonico, Pat

    2012-04-01

    The underlying principles of nuclear medicine imaging involve the use of unsealed sources of radioactivity in the form of radiopharmaceuticals. The ionizing radiations that accompany the decay of the administered radioactivity can be quantitatively detected, measured, and imaged in vivo with instruments such as gamma cameras. This paper reviews the design and operating principles, as well as the capabilities and limitations, of instruments used clinically and preclinically for in vivo radionuclide imaging. These include gamma cameras, single-photon emission computed tomography (SPECT) scanners, and positron emission tomography (PET) scanners. The technical basis of autoradiography is reviewed as well.

  19. [Imaging modalities and therapy options in patients with acute flank pain].

    PubMed

    Grosse, A; Grosse, C

    2014-07-01

    The objective of this article is the description of imaging techniques for the evaluation of patients with acute flank pain and suspicion of urolithiasis and the impact of these techniques in the therapy management of patients with calculi.

  20. Multi-modal label-free imaging based on a femtosecond fiber laser

    PubMed Central

    Xie, Ruxin; Su, Jue; Rentchler, Eric C.; Zhang, Ziyan; Johnson, Carey K.; Shi, Honglian; Hui, Rongqing

    2014-01-01

    We demonstrate multi-mode microscopy based on a single femtosecond fiber laser. Coherent anti-Stokes Raman scattering (CARS), stimulated Raman scattering (SRS) and photothermal images can be obtained simultaneously with this simplified setup. Distributions of lipid and hemoglobin in sliced mouse brain samples and blood cells are imaged. The dependency of signal amplitude on the pump power and pump modulation frequency is characterized, which allows to isolate the impact from different contributions. PMID:25071972

  1. Multi-modal label-free imaging based on a femtosecond fiber laser.

    PubMed

    Xie, Ruxin; Su, Jue; Rentchler, Eric C; Zhang, Ziyan; Johnson, Carey K; Shi, Honglian; Hui, Rongqing

    2014-07-01

    We demonstrate multi-mode microscopy based on a single femtosecond fiber laser. Coherent anti-Stokes Raman scattering (CARS), stimulated Raman scattering (SRS) and photothermal images can be obtained simultaneously with this simplified setup. Distributions of lipid and hemoglobin in sliced mouse brain samples and blood cells are imaged. The dependency of signal amplitude on the pump power and pump modulation frequency is characterized, which allows to isolate the impact from different contributions.

  2. WE-H-206-02: Recent Advances in Multi-Modality Molecular Imaging of Small Animals.

    PubMed

    Tsui, B

    2016-06-01

    Lihong V. Wang: Photoacoustic tomography (PAT), combining non-ionizing optical and ultrasonic waves via the photoacoustic effect, provides in vivo multiscale functional, metabolic, and molecular imaging. Broad applications include imaging of the breast, brain, skin, esophagus, colon, vascular system, and lymphatic system in humans or animals. Light offers rich contrast but does not penetrate biological tissue in straight paths as x-rays do. Consequently, high-resolution pure optical imaging (e.g., confocal microscopy, two-photon microscopy, and optical coherence tomography) is limited to penetration within the optical diffusion limit (∼1 mm in the skin). Ultrasonic imaging, on the contrary, provides fine spatial resolution but suffers from both poor contrast in early-stage tumors and strong speckle artifacts. In PAT, pulsed laser light penetrates tissue and generates a small but rapid temperature rise, which induces emission of ultrasonic waves due to thermoelastic expansion. The ultrasonic waves, orders of magnitude less scattering than optical waves, are then detected to form high-resolution images of optical absorption at depths up to 7 cm, conquering the optical diffusion limit. PAT is the only modality capable of imaging across the length scales of organelles, cells, tissues, and organs (up to whole-body small animals) with consistent contrast. This rapidly growing technology promises to enable multiscale biological research and accelerate translation from microscopic laboratory discoveries to macroscopic clinical practice. PAT may also hold the key to label-free early detection of cancer by in vivo quantification of hypermetabolism, the quintessential hallmark of malignancy.

  3. The risk assessment of Gd2O3:Yb3+/Er3+ nanocomposites as dual-modal nanoprobes for magnetic and fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Huang, Long; Tian, Xiumei; Liu, Jun; Zheng, Cunjing; Xie, Fukang; Li, Li

    2017-02-01

    Our group has synthesized Gd2O3:Yb3+/Er3+ nanocomposites as magnetic/fluorescence imaging successfully in the previous study, which exhibit good uniformity and monodispersibility with a mean size of 7.4 nm. However, their systematic risk assessment remains unknown. In this article, the in vitro biocompatibility of the Gd2O3:Yb3+/Er3+ was assessed on the basis of cell viability and apoptosis. In vivo immunotoxicity was evaluated by monitoring the product of reactive oxygen species (ROS), clusters of differentiation (CD) markers, and superoxide dismutase (SOD) in Balb/c mice. No significant differences were found in cell viability, apoptosis, and immunotoxicity between our Gd2O3:Yb3+/Er3+ and gadodiamide which are used commonly in clinical. Few nanoprobes were localized in the phagosomes of the liver, heart, lung, spleen, kidney, brain, and tumor under the transmission electron microscopy (TEM) images. In addition, our products reveal good T1-weighted contrast enhancement of xenografted murine tumor. Therefore, the above results may contribute to the effective application of Gd2O3:Yb3+/Er3+ as molecular imaging contrast agents and dual-modal nanoprobes for cancer detection.

  4. Biomimetic one-pot synthesis of gold nanoclusters/nanoparticles for targeted tumor cellular dual-modality imaging

    PubMed Central

    2013-01-01

    Biomimetic synthesis has become a promising green pathway to prepare nanomaterials. In this study, bovine serum albumin (BSA)-conjugated gold nanoclusters/nanoparticles were successfully synthesized in water at room temperature by a protein-directed, solution-phase, green synthetic method. The synthesized BSA-Au nanocomplexes have fluorescence emission (588 nm) of gold nanoclusters and surface plasmon resonance of gold nanoparticles. The BSA-Au nanocomplexes display non-cytotoxicity and excellent biocompatibility on MGC803 gastric cancer cells. After conjugation of folic acid molecules, the obtained BSA-Au nanocomplexes showed highly selective targeting for MGC803 cells and dual-modality dark-field and fluorescence imaging. PMID:23587362

  5. Which imaging modality is most effective for identifying pseudotumours in metal-on-metal hip resurfacings requiring revision

    PubMed Central

    Matharu, G. S.; Mansour, R.; Dada, O.; Ostlere, S.; Pandit, H. G.; Murray, D. W.

    2016-01-01

    Aims The aims of this study were to compare the diagnostic test characteristics of ultrasound alone, metal artefact reduction sequence MRI (MARS-MRI) alone, and ultrasound combined with MARS-MRI for identifying intra-operative pseudotumours in metal-on-metal hip resurfacing (MoMHR) patients undergoing revision surgery. Methods This retrospective diagnostic accuracy study involved 39 patients (40 MoMHRs). The time between imaging modalities was a mean of 14.6 days (0 to 90), with imaging performed at a mean of 5.3 months (0.06 to 12) before revision. The prevalence of intra-operative pseudotumours was 82.5% (n = 33). Results Agreement with the intra-operative findings was 82.5% (n = 33) for ultrasound alone, 87.5% (n = 35) for MARS-MRI alone, and 92.5% (n = 37) for ultrasound and MARS-MRI combined. The diagnostic characteristics for ultrasound alone and MARS-MRI alone reached similar sensitivities (90.9% vs 93.9%) and positive predictive values (PPVs; 88.2% vs 91.2%), but higher specificities (57.1% vs 42.9%) and negative predictive values (NPVs; 66.7% vs 50.0%) were achieved with MARS-MRI. Ultrasound and MARS-MRI combined produced 100% sensitivity and 100% NPV, whilst maintaining both specificity (57.1%) and PPV (91.7%). For the identification of a pseudotumour, which was confirmed at revision surgery, agreement was substantial for ultrasound and MARS-MRI combined (κ = 0.69), moderate for MARS-MRI alone (κ = 0.54), and fair for ultrasound alone (κ = 0.36). Discussion These findings suggest that ultrasound and/or MARS-MRI have a role when assessing patients with a MoMHR, with the choice dependent on local financial constraints and the availability of ultrasound expertise. However in patients with a MoMHR who require revision, combined imaging was most effective. Take home message: Combined imaging with ultrasound and MARS-MRI always identified intra-operative pseudotumours if present. Furthermore, if neither imaging modality showed a pseudotumour, one was not

  6. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  7. High-frequency annular array with coaxial illumination for dual-modality ultrasonic and photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Filoux, Erwan; Sampathkumar, Ashwin; Chitnis, Parag V.; Aristizábal, Orlando; Ketterling, Jeffrey A.

    2013-05-01

    This paper presents a combined ultrasound and photoacoustic (PA) imaging (PAI) system used to obtain high-quality, co-registered images of mouse-embryo anatomy and vasculature. High-frequency ultrasound (HFU, >20 MHz) is utilized to obtain high-resolution anatomical images of small animals while PAI provides high-contrast images of the vascular network. The imaging system is based on a 40 MHz, 5-element, 6 mm aperture annular-array transducer with a 800 μm diameter hole through its central element. The transducer was integrated in a cage-plate assembly allowing for a collimated laser beam to pass through the hole so that the optical and acoustic beams were collinear. The assembly was mounted on a two-axis, motorized stage to enable the simultaneous acquisition of co-registered HFU and PA volumetric data. Data were collected from all five elements in receive and a synthetic-focusing algorithm was applied in post-processing to beamform the data and increase the spatial resolution and depth-of-field (DOF) of the HFU and PA images. Phantom measurements showed that the system could achieve high-resolution images (down to 90 μm for HFU and 150 μm for PAI) and a large DOF of >8 mm. Volume renderings of a mouse embryo showed that the scanner allowed for visualizing morphologically precise anatomy of the entire embryo along with corresponding co-registered vasculature. Major head vessels, such as the superior sagittal sinus or rostral vein, were clearly identified as well as limb bud vasculature.

  8. Multi-Modal Imaging in a Mouse Model of Orthotopic Lung Cancer

    PubMed Central

    Patel, Priya; Kato, Tatsuya; Ujiie, Hideki; Wada, Hironobu; Lee, Daiyoon; Hu, Hsin-pei; Hirohashi, Kentaro; Ahn, Jin Young; Zheng, Jinzi; Yasufuku, Kazuhiro

    2016-01-01

    Background Investigation of CF800, a novel PEGylated nano-liposomal imaging agent containing indocyanine green (ICG) and iohexol, for real-time near infrared (NIR) fluorescence and computed tomography (CT) image-guided surgery in an orthotopic lung cancer model in nude mice. Methods CF800 was intravenously administered into 13 mice bearing the H460 orthotopic human lung cancer. At 48 h post-injection (peak imaging agent accumulation time point), ex vivo NIR and CT imaging was performed. A clinical NIR imaging system (SPY®, Novadaq) was used to measure fluorescence intensity of tumor and lung. Tumor-to-background-ratios (TBR) were calculated in inflated and deflated states. The mean Hounsfield unit (HU) of lung tumor was quantified using the CT data set and a semi-automated threshold-based method. Histological evaluation using H&E, the macrophage marker F4/80 and the endothelial cell marker CD31, was performed, and compared to the liposomal fluorescence signal obtained from adjacent tissue sections Results The fluorescence TBR measured when the lung is in the inflated state (2.0 ± 0.58) was significantly greater than in the deflated state (1.42 ± 0.380 (n = 7, p<0.003). Mean fluorescent signal in tumor was highly variable across samples, (49.0 ± 18.8 AU). CT image analysis revealed greater contrast enhancement in lung tumors (a mean increase of 110 ± 57 HU) when CF800 is administered compared to the no contrast enhanced tumors (p = 0.0002). Conclusion Preliminary data suggests that the high fluorescence TBR and CT tumor contrast enhancement provided by CF800 may have clinical utility in localization of lung cancer during CT and NIR image-guided surgery. PMID:27584018

  9. VEGF-loaded graphene oxide as theranostics for multi-modality imaging-monitored targeting therapeutic angiogenesis of ischemic muscle

    NASA Astrophysics Data System (ADS)

    Sun, Zhongchan; Huang, Peng; Tong, Guang; Lin, Jing; Jin, Albert; Rong, Pengfei; Zhu, Lei; Nie, Liming; Niu, Gang; Cao, Feng; Chen, Xiaoyuan

    2013-07-01

    Herein we report the design and synthesis of multifunctional VEGF-loaded IR800-conjugated graphene oxide (GO-IR800-VEGF) for multi-modality imaging-monitored therapeutic angiogenesis of ischemic muscle. The as-prepared GO-IR800-VEGF positively targets VEGF receptors, maintains an elevated level of VEGF in ischemic tissues for a prolonged time, and finally leads to remarkable therapeutic angiogenesis of ischemic muscle. Although more efforts are required to further understand the in vivo behaviors and the long-term toxicology of GO, our work demonstrates the success of using GO for efficient VEGF delivery in vivo by intravenous administration and suggests the great promise of using graphene oxide in theranostic applications for treating ischemic disease.Herein we report the design and synthesis of multifunctional VEGF-loaded IR800-conjugated graphene oxide (GO-IR800-VEGF) for multi-modality imaging-monitored therapeutic angiogenesis of ischemic muscle. The as-prepared GO-IR800-VEGF positively targets VEGF receptors, maintains an elevated level of VEGF in ischemic tissues for a prolonged time, and finally leads to remarkable therapeutic angiogenesis of ischemic muscle. Although more efforts are required to further understand the in vivo behaviors and the long-term toxicology of GO, our work demonstrates the success of using GO for efficient VEGF delivery in vivo by intravenous administration and suggests the great promise of using graphene oxide in theranostic applications for treating ischemic disease. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr01573d

  10. Color intensity projections with hue cycling for intuitive and compressed presentation of motion in medical imaging modalities

    NASA Astrophysics Data System (ADS)

    Cover, Keith S.; Lagerwaard, Frank J.; Verdaasdonk, Rudolf M.

    2013-03-01

    Color intensity projections (CIPs) has been employed to improve the accuracy and reduce the workload of interpreting a series of grayscale images by summarizing the grayscale images in a single color image. CIPs - which has been applied to grayscale images in angiography, 4D CT, nuclear medicine and astronomy - uses the hue, saturation and brightness of the color image to encode the summary information. In CIPs, when a pixel has the same value over the grayscale images, the corresponding pixel in the color image has the identical grayscale color. The arrival time of a signal at each pixel, such as the arrival time of contrast in angiography, is often encoded in the hue (red-yellow-green-light blue-blue-purple) of the corresponding pixel in the color image. In addition, the saturation and brightness of each pixel in the color image encodes the amplitude range and amplitude maximum of the corresponding pixel in the grayscale images. In previous applications of CIPs the hue has been limited to less than one cycle over the color image to avoid the aliasing due to a hue corresponding to more than one arrival time. However, sometimes in applications such as angiography and astronomy, in some instances the aliasing due to increasing the number of cycles of hue over the color image is tolerable as it increases the resolution of arrival time. Key to applying hue cycling effectively is interpolating several grayscale images between each pair of grayscale images. Ideally, the interpreter is allowed to adjust the amount of hue cycling in realtime to find the best setting for each particular CIPs image. CIPs with hue cycling should be a valuable tool in many fields where interpreting a series of grayscale images is required.

  11. Prototypes of Lanthanide(III) Agents Responsive to Enzymatic Activities in Three Complementary Imaging Modalities: Visible/Near-Infrared Luminescence, PARACEST-, and T1-MRI.

    PubMed

    He, Jiefang; Bonnet, Célia S; Eliseeva, Svetlana V; Lacerda, Sara; Chauvin, Thomas; Retailleau, Pascal; Szeremeta, Frederic; Badet, Bernard; Petoud, Stéphane; Tóth, Éva; Durand, Philippe

    2016-03-09

    We report first prototypes of responsive lanthanide(III) complexes that can be monitored independently in three complementary imaging modalities. Through the appropriate choice of lanthanide(III) cations, the same reactive ligand can be used to form complexes providing detection by (i) visible (Tb(3+)) and near-infrared (Yb(3+)) luminescence, (ii) PARACEST- (Tb(3+), Yb(3+)), or (iii) T1-weighted (Gd(3+)) MRI. The use of lanthanide(III) ions of different natures for these imaging modalities induces only a minor change in the structure of complexes that are therefore expected to have a single biodistribution and cytotoxicity.

  12. Automatic Image Registration of Multi-Modal Remotely Sensed Data with Global Shearlet Features

    NASA Technical Reports Server (NTRS)

    Murphy, James M.; Le Moigne, Jacqueline; Harding, David J.

    2016-01-01

    Automatic image registration is the process of aligning two or more images of approximately the same scene with minimal human assistance. Wavelet-based automatic registration methods are standard, but sometimes are not robust to the choice of initial conditions. That is, if the images to be registered are too far apart relative to the initial guess of the algorithm, the registration algorithm does not converge or has poor accuracy, and is thus not robust. These problems occur because wavelet techniques primarily identify isotropic textural features and are less effective at identifying linear and curvilinear edge features. We integrate the recently developed mathematical construction of shearlets, which is more effective at identifying sparse anisotropic edges, with an existing automatic wavelet-based registration algorithm. Our shearlet features algorithm produces more distinct features than wavelet features algorithms; the separation of edges from textures is even stronger than with wavelets. Our algorithm computes shearlet and wavelet features for the images to be registered, then performs least squares minimization on these features to compute a registration transformation. Our algorithm is two-staged and multiresolution in nature. First, a cascade of shearlet features is used to provide a robust, though approximate, registration. This is then refined by registering with a cascade of wavelet features. Experiments across a variety of image classes show an improved robustness to initial conditions, when compared to wavelet features alone.

  13. In vivo optical imaging of human vaginal gel thickness distributions with a probe-based, dual-modality instrument

    NASA Astrophysics Data System (ADS)

    Drake, Tyler K.; DeSoto, Michael G.; Peters, Jennifer J.; Henderson, Marcus H.; Thiele, Bonnie; Bishop, Tammy Sinclair; Murtha, Amy P.; Katz, David F.; Wax, Adam

    2012-11-01

    We used a probe-based dual-modality optical imaging instrument to measure in vivo coating thickness distributions of a gel distributed along the vaginal lumen, in a clinical study. The gel was a surrogate for one delivering an anti-HIV topical microbicide. Imaging data from Fourier-domain multiplexed low-coherence interferometry (mLCI) and fluorimetric measurements were compared to assess the feasibility and accuracy of mLCI in measuring in vivo gel coating thickness distributions. In each study session, 3.5 mL of Replens gel was inserted to the vaginal fornix while the participant was supine. The participant either: 1. remained supine (10 or 60 min) or 2. sat up (1 min), stood up (1 min), sat down (1 min) and returned to the supine position; net elapsed time was 10 or 60 min after which the gel distribution was imaged. Local coating thickness distributions were qualitatively and quantitatively similar. Here mLCI did not accurately measure thicker gel coatings (>0.8 mm), a limitation not seen with fluorimetry. However, mLCI is capable of measuring in vivo microbicide gel distributions with resolution on the order of 10 μm, without the need for exogenous contrast agents, and can accurately capture relevant summary coating measures in good agreement with fluorimetry.

  14. Multi-modal miniature microscope: 4M Device for bio-imaging applications - an overview of the system

    NASA Astrophysics Data System (ADS)

    Tkaczyk, Tomasz S.; Rogers, Jeremy D.; Rahman, Mohammed; Christenson, Todd C.; Gaalema, Stephen; Dereniak, Eustace L.; Richards-Kortum, Rebecca; Descour, Michael R.

    2005-09-01

    The multi-modal miniature microscope (4M) device to image morphology and cytochemistry in vivo is a microscope on a chip including optical, micro-mechanical, and electronic components. This paper describes all major system components: optical system, custom high speed CMOS detector and comb drive actuator. The hybrid sol-gel lenses, their fabrication and assembling technology, optical system parameters, and various operation modes (fluorescence, reflectance, structured illumination) are also discussed. A particularly interesting method is a structured illumination technique that delivers confocal-imaging capabilities and may be used for optical sectioning. For reconstruction of the sectioned layer a sine approximation algorithm is applied. Structured illumination is produced with LIGA fabricated actuator scanning in resonance. The spatial resolution of the system is 1 μm, and was magnified by 4x matching the CMOS pixel size of 4 μm (a lateral magnification is 4:1), and the extent of field of the system is 250μm. An overview of the 4M device is combined with the presentation of imaging results for epithelial cell phantoms with optical properties characteristic of normal and cancerous tissue labeled with nanoparticles.

  15. Imaging findings in a case of Gorlin-Goltz syndrome: a survey using advanced modalities.

    PubMed

    Bronoosh, Pegah; Shakibafar, Ali Reza; Houshyar, Maneli; Nafarzade, Shima

    2011-12-01

    Gorlin-Goltz syndrome is an infrequent multi-systemic disease which is characterized by multiple keratocysts in the jaws, calcification of falx cerebri, and basal cell carcinomas. We report a case of Gorlin-Goltz syndrome in a 23-year-old man with emphasis on image findings of keratocyctic odontogenic tumors (KCOTs) on panoramic radiograph, computed tomography, magnetic resonance (MR) imaging, and Ultrasonography (US). In this case, pericoronal lesions were mostly orthokeratinized odontogenic cyst (OOC) concerning the MR and US study, which tended to recur less. The aim of this report was to clarify the characteristic imaging features of the syndrome-related keratocysts that can be used to differentiate KCOT from OOC. Also, our findings suggested that the recurrence rate of KCOTs might be predicted based on their association to teeth.

  16. Chimpanzees process structural isomorphisms across sensory modalities.

    PubMed

    Ravignani, Andrea; Sonnweber, Ruth

    2017-04-01

    Evolution has shaped animal brains to detect sensory regularities in environmental stimuli. In addition, many species map one-dimensional quantities across sensory modalities, such as conspecific faces to voices, or high-pitched sounds to bright light. If basic patterns like repetitions and identities are frequently perceived in different sensory modalities, it could be advantageous to detect cross-modal isomorphisms, i.e. develop modality-independent representations of structural features, exploitable in visual, tactile, and auditory processing. While cross-modal mappings are common in the animal kingdom, the ability to map similar (isomorphic) structures across domains has been demonstrated in humans but no other animals. We tested cross-modal isomorphisms in two chimpanzees (Pan troglodytes). Individuals were previously trained to choose structurally 'symmetric' image sequences (two identical geometrical shapes separated by a different shape) presented beside 'edge' sequences (two identical shapes preceded or followed by a different one). Here, with no additional training, the choice between symmetric and edge visual sequences was preceded by playback of three concatenated sounds, which could be symmetric (mimicking the symmetric structure of reinforced images) or edge. The chimpanzees spontaneously detected a visual-auditory isomorphism. Response latencies in choosing symmetric sequences were shorter when presented with (structurally isomorphic) symmetric, rather than edge, sound triplets: The auditory stimuli interfered, based on their structural properties, with processing of the learnt visual rule. Crucially, the animals had neither been exposed to the acoustic sequences before the experiment, nor were they trained to associate sounds to images. Our result provides the first evidence of structure processing across modalities in a non-human species. It suggests that basic cross-modal abstraction capacities transcend linguistic abilities and might involve

  17. High-frequency 3D echodentographic imaging modality for early assessment of periodontal diseases: in vitro study

    NASA Astrophysics Data System (ADS)

    Mahmoud, Ahmed M.; Ngan, Peter; Crout, Richard; Mukdadi, Osama M.

    2009-02-01

    The use of ultrasound in dentistry is still an open growing area of research. Currently, there is a lack of imaging modalities to accurately predict minute structures and defects in the jawbone. In particular, the inability of 2D radiographic images to detect bony periodontal defects resulted from infection of the periodontium. This study investigates the feasibility of high frequency ultrasound to reconstruct high resolution 3D surface images of human jawbone. Methods: A dentate and non-dentate mandibles were used in this study. The system employs high frequency single-element ultrasound focused transducers (15-30 MHz) for scanning. Continuous acquisition using a 1 GHz data acquisition card is synchronized with a high precision two-dimensional stage positioning system of +/-1 μm resolution for acquiring accurate and quantitative measurements of the mandible in vitro. Radio frequency (RF) signals are acquired laterally 44-45.5 μm apart for each frame. Different frames are reconstructed 500 μm apart for the 3D reconstruction. Signal processing algorithms are applied on the received ultrasound signals for filtering, focusing, and envelope detection before frame reconstruction. Furthermore, an edge detection technique is adopted to detect the bone surface in each frame. Finally, all edges are combined together in order to render a 3D surface image of the jawbone. Major anatomical landmarks on the resultant images were confirmed with the anatomical structures on the mandibles to show the efficacy of the system. Comparison were also made with conventional 2D radiographs to show the superiority of the ultrasound imaging system in diagnosing small defects in the lateral, axial and elevation planes of space. Results: The landmarks on all ultrasound images matched with those on the mandible, indicating the efficacy of the system in detecting small structures in human jaw bones. Comparison with conventional 2D radiographic images of the same mandible showed superiority of

  18. Fluorescent magnetic Fe3 O4 /rare Earth colloidal nanoparticles for dual-modality imaging.

    PubMed

    Zhu, Haie; Shang, Yalei; Wang, Wenhao; Zhou, Yingjie; Li, Penghui; Yan, Kai; Wu, Shuilin; Yeung, Kelvin W K; Xu, Zushun; Xu, Haibo; Chu, Paul K

    2013-09-09

    Fluorescent magnetic colloidal nanoparticles (FMCNPs) are produced by a two-step, seed emulsifier-free emulsion polymerization in the presence of oleic acid and sodium undecylenate-modified Fe3 O4 nanoparticles (NPs). The Fe3 O4 /poly(St-co-GMA) nanoparticles are first synthesized as the seed and Eu(AA)3 Phen is copolymerized with the remaining St and GMA to form the fluorescent polymer shell in the second step. The uniform core-shell structured FMCNPs with a mean diameter of 120 nm exhibit superparamagnetism with saturation magnetization of 1.92 emu/g. Red luminescence from the FMCNPs is confirmed by the salient fluorescence emission peaks of europium ions at 594 and 619 nm as well as 2-photon confocal scanning laser microscopy. The in vitro cytotoxicity test conducted using the MTT assay shows good cytocompatibility and the T2 relaxivity of the FMCNPs is 353.86 mM(-1) S(-1) suggesting its potential in magnetic resonance imaging (MRI). In vivo MRI studies based on a rat model show significantly enhanced T2 -weighted images of the liver after administration and prussian blue staining of the liver tissue slice reveals accumulation of FMCNPs in the organ. The cytocompatibility, superparamagnetism, and excellent fluorescent properties of FMCNPs make them suitable for biological imaging probes in MRI and optical imaging.

  19. Multiphoton microscopy as a diagnostic imaging modality for pancreatic neoplasms without hematoxylin and eosin stains

    NASA Astrophysics Data System (ADS)

    Chen, Youting; Chen, Jing; Chen, Hong; Hong, Zhipeng; Zhu, Xiaoqin; Zhuo, Shuangmu; Chen, Yanling; Chen, Jianxin

    2014-09-01

    Hematoxylin and eosin (H&E) staining of tissue samples is the standard approach in histopathology for imaging and diagnosing cancer. Recent reports have shown that multiphoton microscopy (MPM) provides better sample interface with single-cell resolution, which enhances traditional H&E staining and offers a powerful diagnostic tool with potential applications in oncology. The purpose of this study was to further expand the versatility of MPM by establishing the optical parameters required for imaging unstained histological sections of pancreatic neoplasms, thereby providing an efficient and environmentally sustainable alternative to H&E staining while improving the accuracy of pancreatic cancer diagnoses. We found that the high-resolution MPM images clearly distinguish between the structure of normal pancreatic tissues compared with pancreatic neoplasms in unstained histological sections, and discernable differences in tissue architecture and cell morphology between normal versus tumorigenic cells led to enhanced optical diagnosis of cancerous tissue. Moreover, quantitative assessment of the cytomorphological features visualized from MPM images showed significant differences in the nuclear-cytoplasmic ratios of pancreatic neoplasms compared with normal pancreas, as well as further distinguished pancreatic malignant tumors from benign tumors. These results indicate that the MPM could potentially serve as an optical tool for the diagnosis of pancreatic neoplasms in unstained histological sections.

  20. Cone Beam Computed Tomography-Dawn of A New Imaging Modality in Orthodontics.

    PubMed

    Mamatha, J; Chaitra, K R; Paul, Renji K; George, Merin; Anitha, J; Khanna, Bharti

    2015-01-01

    Today, we are in a world of innovations, and there are various diagnostics aids that help to take a decision regarding treatment in a well-planned way. Cone beam computed tomography (CBCT) has been a vital tool for imaging diagnostic tool in orthodontics. This article reviews case reports during orthodontic treatment and importance of CBCT during the treatment evaluation.

  1. Cone Beam Computed Tomography-Dawn of A New Imaging Modality in Orthodontics

    PubMed Central

    Mamatha, J; Chaitra, K R; Paul, Renji K; George, Merin; Anitha, J; Khanna, Bharti

    2015-01-01

    Today, we are in a world of innovations, and there are various diagnostics aids that help to take a decision regarding treatment in a well-planned way. Cone beam computed tomography (CBCT) has been a vital tool for imaging diagnostic tool in orthodontics. This article reviews case reports during orthodontic treatment and importance of CBCT during the treatment evaluation. PMID:26225116

  2. Multiphoton microscopy as a diagnostic imaging modality for pancreatic neoplasms without hematoxylin and eosin stains.

    PubMed

    Chen, Youting; Chen, Jing; Chen, Hong; Hong, Zhipeng; Zhu, Xiaoqin; Zhuo, Shuangmu; Chen, Yanling; Chen, Jianxin

    2014-09-01

    Hematoxylin and eosin (H&E) staining of tissue samples is the standard approach in histopathology for imaging and diagnosing cancer. Recent reports have shown that multiphoton microscopy (MPM) provides better sample interface with single-cell resolution, which enhances traditional H&E staining and offers a powerful diagnostic tool with potential applications in oncology. The purpose of this study was to further expand the versatility of MPM by establishing the optical parameters required for imaging unstained histological sections of pancreatic neoplasms, thereby providing an efficient and environmentally sustainable alternative to H&E staining while improving the accuracy of pancreatic cancer diagnoses. We found that the high-resolution MPM images clearly distinguish between the structure of normal pancreatic tissues compared with pancreatic neoplasms in unstained histological sections, and discernable differences in tissue architecture and cell morphology between normal versus tumorigenic cells led to enhanced optical diagnosis of cancerous tissue. Moreover, quantitative assessment of the cytomorphological features visualized from MPM images showed significant differences in the nuclear–cytoplasmic ratios of pancreatic neoplasms compared with normal pancreas, as well as further distinguished pancreatic malignant tumors from benign tumors. These results indicate that the MPM could potentially serve as an optical tool for the diagnosis of pancreatic neoplasms in unstained histological sections.

  3. 68Ga-labeled superparamagnetic iron oxide nanoparticles (SPIONs) for multi-modality PET/MR/Cherenkov luminescence imaging of sentinel lymph nodes

    PubMed Central

    Madru, Renata; Tran, Thuy A; Axelsson, Johan; Ingvar, Christian; Bibic, Adnan; Ståhlberg, Freddy; Knutsson, Linda; Strand, Sven-Erik

    2014-01-01

    The aim of this study was to develop 68Ga-SPIONs for use as a single contrast agent for dynamic, quantitative and high resolution PET/MR imaging of Sentinel Lymph Node (SLN). In addition 68Ga enables Cherenkov light emission which can be used for optical guidance during resection of SLN. SPIONs were labeled with 68Ga in ammonium acetate buffer, pH 5.5. The labeling yield and stability in human serum were determined using instant thin layer chromatography. An amount of 0.07-0.1 mL (~5-10 MBq, 0.13 mg Fe) of 68Ga-SPIONs was subcutaneously injected in the hind paw of rats. The animals were imaged at 0-3 h and 25 h post injection with PET/CT, 9.4 T MR and CCDbased Cherenkov optical systems. A biodistribution study was performed by dissecting and measuring the radioactivity in lymph nodes, kidneys, spleen, liver and the injection site. The labeling yield was 97.3 ± 0.05% after 15 min and the 68Ga-SPIONs were stable in human serum. PET, MR and Cherenkov luminescence imaging clearly visualized the SLN. Biodistribution confirmed a high uptake of the 68Ga-SPIONs within the SLN. We conclude that generator produced 68Ga can be labeled to SPIONs. Subcutaneously injected 68Ga-SPIONs can enhance the identification of the SLNs by combining sensitive PET and high resolution MR imaging. Clinically, hybrid PET/MR cameras are already in use and 68Ga-SPIONs have a great potential as a single-dose, tri-modality agent for diagnostic imaging and potential Cherenkov luminescent guided resection of SLN. PMID:24380046

  4. Cy5.5 conjugated MnO nanoparticles for magnetic resonance/near-infrared fluorescence dual-modal imaging of brain gliomas.

    PubMed

    Chen, Ning; Shao, Chen; Li, Shuai; Wang, Zihao; Qu, Yanming; Gu, Wei; Yu, Chunjiang; Ye, Ling

    2015-11-01

    The fusion of molecular and anatomical modalities facilitates more reliable and accurate detection of tumors. Herein, we prepared the PEG-Cy5.5 conjugated MnO nanoparticles (MnO-PEG-Cy5.5 NPs) with magnetic resonance (MR) and near-infrared fluorescence (NIRF) imaging modalities. The applicability of MnO-PEG-Cy5.5 NPs as a dual-modal (MR/NIRF) imaging nanoprobe for the detection of brain gliomas was investigated. In vivo MR contrast enhancement of the MnO-PEG-Cy5.5 nanoprobe in the tumor region was demonstrated. Meanwhile, whole-body NIRF imaging of glioma bearing nude mouse exhibited distinct tumor localization upon injection of MnO-PEG-Cy5.5 NPs. Moreover, ex vivo CLSM imaging of the brain slice hosting glioma indicated the preferential accumulation of MnO-PEG-Cy5.5 NPs in the glioma region. Our results therefore demonstrated the potential of MnO-PEG-Cy5.5 NPs as a dual-modal (MR/NIRF) imaging nanoprobe in improving the diagnostic efficacy by simultaneously providing anatomical information from deep inside the body and more sensitive information at the cellular level.

  5. A novel optical detector concept for dedicated and multi-modality in vivo small animal imaging

    NASA Astrophysics Data System (ADS)

    Peter, Jörg; Schulz, Ralf B.; Unholtz, Daniel; Semmler, Wolfhard

    2007-07-01

    An optical detector suitable for inclusion in tomographic arrangements for non-contact in vivo bioluminescence and fluorescence imaging applications is proposed. It consists of a microlens array (MLA) intended for field-of-view definition, a large-field complementary metal-oxide-semiconductor (CMOS) chip for light detection, a septum mask for cross-talk suppression, and an exchangeable filter to block excitation light. Prototype detector units with sensitive areas of 2.5 cm x 5 cm each were assembled. The CMOS sensor constitutes a 512 x 1024 photodiode matrix at 48 μm pixel pitch. Refractive MLAs with plano-convex lenses of 480 μm in diameter and pitch were selected resulting in a 55 x 105 lens matrix. The CMOS sensor is aligned on the focal plane of the MLA at 2.15mm distance. To separate individual microlens images an opaque multi-bore septum mask of 2.1mm in thickness and bore diameters of 400 μm at 480 μm pitch, aligned with the lens pattern, is placed between MLA and CMOS. Intrinsic spatial detector resolution and sensitivity was evaluated experimentally as a function of detector-object distance. Due to its small overall dimensions such detectors can be favorably packed for tomographic imaging (optical diffusion tomography, ODT) yielding complete 2 π field-of-view coverage. We also present a design study of a device intended to simultaneously image positron labeled substrates (positron emission tomography, PET) and optical molecular probes in small animals such as mice and rats. It consists of a cylindrical allocation of optical detector units which form an inner detector ring while PET detector blocks are mounted in radial extension, those gaining complementary information in a single, intrinsically coregistered experimental data acquisition study. Finally, in a second design study we propose a method for integrated optical and magnetic resonance imaging (MRI) which yields in vivo functional/molecular information that is intrinsically registered with the

  6. Multi-Modal Image Registration and Matching for Localization of a Balloon on Titan

    NASA Technical Reports Server (NTRS)

    Ansar, Adnan I.

    2011-01-01

    A solution was developed that matches visible/IR imagery aboard a balloon in Saturn's moon Titan's atmosphere to SAR (synthetic aperture radar) and visible/IR data acquired from orbit. A balloon in Titan's atmosphere must be able to localize itself autonomously both globally and with respect to local terrain. The orbital data is used to provide the balloon imagery with global context. The work is novel in applying mutual information (MI) to orbital vs. aerial data. There are unique challenges in this setting. Image offsets are much higher than in medical imaging, there is local distortion due to 3D terrain relief, and the fields of regard from orbit and from the air are quite different.

  7. Tri-modal microscopy with multiphoton and optical coherence microscopy/tomography for multi-scale and multi-contrast imaging

    PubMed Central

    Chong, Shau Poh; Lai, Tom; Zhou, Yifeng; Tang, Shuo

    2013-01-01

    Multi-scale multimodal microscopy is a very useful technique by providing multiple imaging contrasts with adjustable field of views and spatial resolutions. Here, we present a tri-modal microscope combining multiphoton microscopy (MPM), optical coherence microscopy (OCM) and optical coherence tomography (OCT) for subsurface visualization of biological tissues. The advantages of the tri-modal system are demonstrated on various biological samples. It enables the visualization of multiple intrinsic contrasts including scattering, two-photon excitation fluorescence (TPEF), and second harmonic generation (SHG). It also enables a rapid scanning over a large tissue area and a high resolution zoom-in for cellular-level structures on regions of interest. The tri-modal microscope can be important for label-free imaging to obtain a sufficient set of parameters for reliable sample analysis. PMID:24049679

  8. Development of an Automated Modality-Independent Elastographic Image Analysis System for Tumor Screening

    DTIC Science & Technology

    2006-02-01

    increased computational complexity, developing and testing metrics for the evaluation of reconstructions, and the fabrication of a compression chamber... tested on a tissue-like polymer phantom. elastography, breast cancer screening, image processing 16. SECURITY CLASSIFICATION OF: 17. LIMITATION...design and a share of 100 CPUs on the Vanderbilt University Advanced Computing Center for Research and 5 Education cluster, this has been tested to be

  9. Multi-modality imaging review of congenital abnormalities of kidney and upper urinary tract

    PubMed Central

    Ramanathan, Subramaniyan; Kumar, Devendra; Khanna, Maneesh; Al Heidous, Mahmoud; Sheikh, Adnan; Virmani, Vivek; Palaniappan, Yegu

    2016-01-01

    Congenital abnormalities of the kidney and urinary tract (CAKUT) include a wide range of abnormalities ranging from asymptomatic ectopic kidneys to life threatening renal agenesis (bilateral). Many of them are detected in the antenatal or immediate postnatal with a significant proportion identified in the adult population with varying degree of severity. CAKUT can be classified on embryological basis in to abnormalities in the renal parenchymal development, aberrant embryonic migration and abnormalities of the collecting system. Renal parenchymal abnormalities include multi cystic dysplastic kidneys, renal hypoplasia, number (agenesis or supernumerary), shape and cystic renal diseases. Aberrant embryonic migration encompasses abnormal location and fusion anomalies. Collecting system abnormalities include duplex kidneys and Pelvi ureteric junction obstruction. Ultrasonography (US) is typically the first imaging performed as it is easily available, non-invasive and radiation free used both antenatally and postnatally. Computed tomography (CT) and magnetic resonance imaging (MRI) are useful to confirm the ultrasound detected abnormality, detection of complex malformations, demonstration of collecting system and vascular anatomy and more importantly for early detection of complications like renal calculi, infection and malignancies. As CAKUT are one of the leading causes of end stage renal disease, it is important for the radiologists to be familiar with the varying imaging appearances of CAKUT on US, CT and MRI, thereby helping in prompt diagnosis and optimal management. PMID:26981222

  10. Rational design of magnetic nanorattles as contrast agents for ultrasound/magnetic resonance dual-modality imaging.

    PubMed

    Yang, Peng; Wang, Fang; Luo, Xianfu; Zhang, Yuting; Guo, Jia; Shi, Weibin; Wang, Changchun

    2014-08-13

    Nanorattles, as promising functional hollow nanomaterials, show considerable advantages in a variety of applications for drug delivery, biosensors, and biomedical imaging because of their tailored ability in both the movable core and shell. In this study, we formulate a facile controllable route to synthesize a monodisperse magnetic nanorattle with an Fe3O4 superparticle as the core and poly(vinylsilane) (PVS) as the outer shell (Fe3O4@air@PVS) using the polymer-backbone-transition strategy. In the process of synthesis, besides acting as the precursor for the PVS shells of nanorattles, organosilica (o-SiO2) plays the role of template for the middle cavities. The structures of nanorattles can be easily formed via etching treatment of NaOH solution. Through encapsulating sensitive perfluorohexane (PFH) in the cavities of Fe3O4@air@PVS, the biocompatible magnetic nanosystem shows a relatively stable ultrasound signal intensity and a high r2 value of 62.19 mM(-1) s(-1) for magnetic resonance imaging (MRI). After intravenous administration of nanorattles to a healthy rat, dramatically positively enhanced ultrasound imaging and negatively enhanced T2-weighted MRI are detected in the liver. Furthermore, when the Fe3O4@PFH@PVS nanorattles are administered to tumor-bearing mice, a significant passive accumulation in the tumor via an electron paramagnetic resonance effect is detected by both ultrasound imaging and MRI. In vivo experiments indicate that the obtained Fe3O4@PFH@PVS nanorattles can be used as dual-modality contrast agents for simultaneous ultrasound and MRI detection.

  11. Imaging brain activity during seizures in freely behaving rats using a miniature multi-modal imaging system

    PubMed Central

    Sigal, Iliya; Koletar, Margaret M.; Ringuette, Dene; Gad, Raanan; Jeffrey, Melanie; Carlen, Peter L.; Stefanovic, Bojana; Levi, Ofer

    2016-01-01

    We report on a miniature label-free imaging system for monitoring brain blood flow and blood oxygenation changes in awake, freely behaving rats. The device, weighing 15 grams, enables imaging in a ∼ 2 × 2 mm field of view with 4.4 μm lateral resolution and 1 − 8 Hz temporal sampling rate. The imaging is performed through a chronically-implanted cranial window that remains optically clear between 2 to > 6 weeks after the craniotomy. This imaging method is well suited for longitudinal studies of chronic models of brain diseases and disorders. In this work, it is applied to monitoring neurovascular coupling during drug-induced absence-like seizures 6 weeks following the craniotomy. PMID:27699123

  12. The coronagraphic Modal Wavefront Sensor: a hybrid focal-plane sensor for the high-contrast imaging of circumstellar environments

    NASA Astrophysics Data System (ADS)

    Wilby, M. J.; Keller, C. U.; Snik, F.; Korkiakoski, V.; Pietrow, A. G. M.

    2017-01-01

    The raw coronagraphic performance of current high-contrast imaging instruments is limited by the presence of a quasi-static speckle (QSS) background, resulting from instrumental Non-Common Path Errors (NCPEs). Rapid development of efficient speckle subtraction techniques in data reduction has enabled final contrasts of up to 10-6 to be obtained, however it remains preferable to eliminate the underlying NCPEs at the source. In this work we introduce the coronagraphic Modal Wavefront Sensor (cMWS), a new wavefront sensor suitable for real-time NCPE correction. This combines the Apodizing Phase Plate (APP) coronagraph with a holographic modal wavefront sensor to provide simultaneous coronagraphic imaging and focal-plane wavefront sensing with the science point-spread function. We first characterise the baseline performance of the cMWS via idealised closed-loop simulations, showing that the sensor is able to successfully recover diffraction-limited coronagraph performance over an effective dynamic range of ±2.5 radians root-mean-square (rms) wavefront error within 2-10 iterations, with performance independent of the specific choice of mode basis. We then present the results of initial on-sky testing at the William Herschel Telescope, which demonstrate that the sensor is capable of NCPE sensing under realistic seeing conditions via the recovery of known static aberrations to an accuracy of 10 nm (0.1 radians) rms error in the presence of a dominant atmospheric speckle foreground. We also find that the sensor is capable of real-time measurement of broadband atmospheric wavefront variance (50% bandwidth, 158 nm rms wavefront error) at a cadence of 50 Hz over an uncorrected telescope sub-aperture. When combined with a suitable closed-loop adaptive optics system, the cMWS holds the potential to deliver an improvement of up to two orders of magnitude over the uncorrected QSS floor. Such a sensor would be eminently suitable for the direct imaging and spectroscopy of

  13. Direct laser additive fabrication system with image feedback control

    DOEpatents

    Griffith, Michelle L.; Hofmeister, William H.; Knorovsky, Gerald A.; MacCallum, Danny O.; Schlienger, M. Eric; Smugeresky, John E.

    2002-01-01

    A closed-loop, feedback-controlled direct laser fabrication system is disclosed. The feedback refers to the actual growth conditions obtained by real-time analysis of thermal radiation images. The resulting system can fabricate components with severalfold improvement in dimensional tolerances and surface finish.

  14. Black titania-based theranostic nanoplatform for single NIR laser induced dual-modal imaging-guided PTT/PDT.

    PubMed

    Mou, Juan; Lin, Tianquan; Huang, Fuqiang; Chen, Hangrong; Shi, Jianlin

    2016-04-01

    Substantially different from traditional combinatorial-treatment of photothermal therapy (PTT) and photodynamic therapy (PDT) by using multi-component nanocomposite under excitation of separate wavelength, a novel single near infrared (NIR) laser-induced multifunctional theranostic nanoplatform has been rationally and successfully constructed by a single component black titania (B-TiO2-x) for effective imaging-guided cancer therapy for the first time. This multifunctional PEGylated B-TiO2-x shows high dispersity/stability in aqueous solution, excellent hemo/histocompatibility and broad absorption ranging from NIR to ultraviolet (UV). Both in vitro and in vivo results well demonstrated that such a novel multifunctional theranostic nanoplaform could achieve high therapeutic efficacy of simultaneous and synergistic PTT/PDT under the guidance of infrared thermal/photoacoustic (PA) dual-modal imaging, which was triggered by a single NIR laser. This research circumvents the conventional obstacles of using multi-component nanocomposites, UV light and high laser power density. Furthermore, negligible side effects to blood and main tissues could be found in 3 months' investigation, facilitating its potential biomedical application.

  15. 3D Deep Learning for Multi-modal Imaging-Guided Survival Time Prediction of Brain Tumor Patients

    PubMed Central

    Nie, Dong; Zhang, Han; Adeli, Ehsan; Liu, Luyan

    2016-01-01

    High-grade glioma is the most aggressive and severe brain tumor that leads to death of almost 50% patients in 1–2 years. Thus, accurate prognosis for glioma patients would provide essential guidelines for their treatment planning. Conventional survival prediction generally utilizes clinical information and limited handcrafted features from magnetic resonance images (MRI), which is often time consuming, laborious and subjective. In this paper, we propose using deep learning frameworks to automatically extract features from multi-modal preoperative brain images (i.e., T1 MRI, fMRI and DTI) of high-grade glioma patients. Specifically, we adopt 3D convolutional neural networks (CNNs) and also propose a new network architecture for using multi-channel data and learning supervised features. Along with the pivotal clinical features, we finally train a support vector machine to predict if the patient has a long or short overall survival (OS) time. Experimental results demonstrate that our methods can achieve an accuracy as high as 89.9% We also find that the learned features from fMRI and DTI play more important roles in accurately predicting the OS time, which provides valuable insights into functional neuro-oncological applications. PMID:28149967

  16. 3D Deep Learning for Multi-modal Imaging-Guided Survival Time Prediction of Brain Tumor Patients.

    PubMed

    Nie, Dong; Zhang, Han; Adeli, Ehsan; Liu, Luyan; Shen, Dinggang

    2016-10-01

    High-grade glioma is the most aggressive and severe brain tumor that leads to death of almost 50% patients in 1-2 years. Thus, accurate prognosis for glioma patients would provide essential guidelines for their treatment planning. Conventional survival prediction generally utilizes clinical information and limited handcrafted features from magnetic resonance images (MRI), which is often time consuming, laborious and subjective. In this paper, we propose using deep learning frameworks to automatically extract features from multi-modal preoperative brain images (i.e., T1 MRI, fMRI and DTI) of high-grade glioma patients. Specifically, we adopt 3D convolutional neural networks (CNNs) and also propose a new network architecture for using multi-channel data and learning supervised features. Along with the pivotal clinical features, we finally train a support vector machine to predict if the patient has a long or short overall survival (OS) time. Experimental results demonstrate that our methods can achieve an accuracy as high as 89.9% We also find that the learned features from fMRI and DTI play more important roles in accurately predicting the OS time, which provides valuable insights into functional neuro-oncological applications.

  17. Improved CT and MR image registration with the introduction of a dual-modality contrast agent: performance assessment using quantitative and information theoretic methods

    NASA Astrophysics Data System (ADS)

    Hoisak, Jeremy D. P.; Zheng, Jinzi; Allen, Christine; Jaffray, David A.

    2008-03-01

    The ability of computed tomography (CT) and magnetic resonance (MR) imaging to visualize and discriminate between normal and diseased tissues is improved with contrast agents, which are designed to differentially accumulate in tissues and modify their inherent imaging signal. Conventional contrast agents are limited to a single modality and require fast acquisitions due to rapid clearance following injection. Encapsulation of iohexol and gadoteridol within a nano-engineered liposome has been achieved and can increase their in vivo half-life to several days. We hypothesize that the persistence of this contrast agent in vivo, and the simultaneous co-localized contrast enhancement across modalities will improve longitudinal image registration. This work investigates the in vivo registration performance of the dual-modality contrast agent under realistic conditions. Previous characterizations of single-modality contrast agents were limited to qualitative inspections of signal intensity enhancement. We present quantitative, information theoretic methods for assessing image registration performance. The effect of increased localized contrast upon the mutual information of the MR and CT image sets was shown to increase post-injection. Images registered post- injection had a decreased registration error compared with pre-contrast images. Performance was maintained over extended time frames, contrast agent concentrations, and with decreased field-of-view. This characterization allows optimization of the contrast agent against desired performance for a given imaging task. The ability to perform robust longitudinal image registration is essential for pre-clinical investigations of tumor development, monitoring of therapy response, and therapy guidance over multiple fractions where registration of online cone-beam CT to planning CT and MR is necessary.

  18. Optical scatter imaging: a microscopic modality for the rapid morphological assay of living cells

    NASA Astrophysics Data System (ADS)

    Boustany, Nada N.

    2007-02-01

    Tumors derived from epithelial cells comprise the majority of human tumors and their growth results from the accumulation of multiple mutations affecting cellular processes critical for tissue homeostasis, including cell proliferation and cell death. To understand these processes and address the complexity of cancer cell function, multiple cellular responses to different experimental conditions and specific genetic mutations must be analyzed. Fundamental to this endeavor is the development of rapid cellular assays in genetically defined cells, and in particular, the development of optical imaging methods that allow dynamic observation and real-time monitoring of cellular processes. In this context, we are developing an optical scatter imaging technology that is intended to bridge the gap between light and electron microscopy by rapidly providing morphometric information about the relative size and shape of non-spherical organelles, with sub-wavelength resolution. Our goal is to complement current microscopy techniques used to study cells in-vitro, especially in long-term time-lapse studies of living cells, where exogenous labels can be toxic, and electron microscopy will destroy the sample. The optical measurements are based on Fourier spatial filtering in a standard microscope, and could ultimately be incorporated into existing high-throughput diagnostic platforms for cancer cell research and histopathology of neoplastic tissue arrays. Using an engineered epithelial cell model of tumor formation, we are currently studying how organelle structure and function are altered by defined genetic mutations affecting the propensity for cell death and oncogenic potential, and by environmental conditions promoting tumor growth. This talk will describe our optical scatter imaging technology and present results from our studies on apoptosis, and the function of BCL-2 family proteins.

  19. Dual-Modality Noninvasive Mapping of Sentinel Lymph Node by Photoacoustic and Near-Infrared Fluorescent Imaging Using Dye-Loaded Mesoporous Silica Nanoparticles.

    PubMed

    Liu, Zhiguo; Rong, Pengfei; Yu, Lun; Zhang, Xintong; Yang, Cejun; Guo, Fei; Zhao, Yanzhong; Zhou, Kechao; Wang, Wei; Zeng, Wenbin

    2015-09-08

    The imaging of sentinel lymph nodes (SLNs), the first defense against primary tumor metastasis, has been considered as an important strategy for noninvasive tracking tumor metastasis in clinics. In this study, we developed an imaging contrast system based on fluorescent dye-loaded mesoporous silica nanoparticles (MSNPs) that integrate near-infrared (NIR) fluorescent and photoacoustic (PA) imaging modalities for efficient SLN mapping. By balancing the ratio of dye and nanoparticles for simultaneous optimization of dual-modality imaging (NIR and PA), the dye encapsulated MSNP platform was set up to generate both a moderate NIR emission and PA signals simultaneously. Moreover, the underlying mechanisms of the relevance between optical and PA properties were discovered. Subsequently, dual-modality imaging was achieved to visualize tumor draining SLNs up to 2 weeks in a 4T1 tumor metastatic model. Obvious differences in uptake rate and contrast between metastatic and normal SLNs were observed both in vivo and ex vivo. Based on all these imaging data, it was demonstrated that the dye-loaded MSNPs allow detection of regional lymph nodes in vivo with time-domain NIR fluorescent and PA imaging methods efficiently.

  20. Dual-Modality Activity-Based Probes as Molecular Imaging Agents for Vascular Inflammation.

    PubMed

    Withana, Nimali P; Saito, Toshinobu; Ma, Xiaowei; Garland, Megan; Liu, Changhao; Kosuge, Hisanori; Amsallem, Myriam; Verdoes, Martijn; Ofori, Leslie O; Fischbein, Michael; Arakawa, Mamoru; Cheng, Zhen; McConnell, Michael V; Bogyo, Matthew

    2016-10-01

    Macrophages are cellular mediators of vascular inflammation and are involved in the formation of atherosclerotic plaques. These immune cells secrete proteases such as matrix metalloproteinases and cathepsins that contribute to disease formation and progression. Here, we demonstrate that activity-based probes (ABPs) targeting cysteine cathepsins can be used in murine models of atherosclerosis to noninvasively image activated macrophage populations using both optical and PET/CT methods. The probes can also be used to topically label human carotid plaques demonstrating similar specific labeling of activated macrophage populations.

  1. Aqueous synthesis of Ag and Mn co-doped In2S3/ZnS quantum dots with tunable emission for dual-modal targeted imaging.

    PubMed

    Lai, Pei-Yu; Huang, Chih-Ching; Chou, Tzung-Han; Ou, Keng-Liang; Chang, Jia-Yaw

    2017-03-01

    Here, we present the microwave-assisted synthesis of In2S3/ZnS core/shell quantum dots (QDs) co-doped with Ag(+) and Mn(2+) (referred to as AgMn:In2S3/ZnS). Ag(+) altered the optical properties of the host QDs, whereas the spin magnetic moment (S=5/2) of Mn(2+) efficiently induced the longitudinal relaxation of water protons. To the best of our knowledge, this is the first report of the aqueous synthesis of color-tunable AgMn:In2S3/ZnS core/shell QDs with magnetic properties. The synthetic procedure is rapid, facile, reproducible, and scalable. The obtained QDs offered a satisfactory quantum yield (45%), high longitudinal relaxivity (6.84s(-1)mM(-1)), and robust photostability. In addition, they exhibited excellent stability over a wide pH range (5-12) and high ionic strength (0.15-2.0M NaCl). As seen by confocal microscopy and magnetic resonance imaging, AgMn:In2S3/ZnS conjugated to hyaluronic acid (referred to as AgMn:In2S3/ZnS@HA) efficiently and specifically targeted cluster determinant 44, a receptor overexpressed on cancer cells. Moreover, AgMn:In2S3/ZnS@HA showed negligible cytotoxicity in vitro and in vivo, rendering it a promising diagnostic probe for dual-modal imaging in clinical applications.

  2. Self-assembled dual-modality contrast agents for non-invasive stem cell tracking via near-infrared fluorescence and magnetic resonance imaging.

    PubMed

    Liu, Hong; Tan, Yan; Xie, Lisi; Yang, Lei; Zhao, Jing; Bai, Jingxuan; Huang, Ping; Zhan, Wugen; Wan, Qian; Zou, Chao; Han, Yali; Wang, Zhiyong

    2016-09-15

    Stem cells hold great promise for treating various diseases. However, one of the main drawbacks of stem cell therapy is the lack of non-invasive image-tracking technologies. Although magnetic resonance imaging (MRI) and near-infrared fluorescence (NIRF) imaging have been employed to analyse cellular and subcellular events via the assistance of contrast agents, the sensitivity and temporal resolution of MRI and the spatial resolution of NIRF are still shortcomings. In this study, superparamagnetic iron oxide nanocrystals and IR-780 dyes were co-encapsulated in stearic acid-modified polyethylenimine to form a dual-modality contrast agent with nano-size and positive charge. These resulting agents efficiently labelled stem cells and did not influence the cellular viability and differentiation. Moreover, the labelled cells showed the advantages of dual-modality imaging in vivo.

  3. Optimal addition of images for detection and photometry

    NASA Technical Reports Server (NTRS)

    Fischer, Philippe; Kochanski, Greg P.

    1994-01-01

    In this paper we describe weighting techniques used for the optimal coaddition of charge coupled devices (CCD) frames with differing characteristics. Optimal means maximum signal to noise (S/N) for stellar objects. We derive formulas for four applications: (1) object detection via matched filter, (2) object detection identical to DAOFIND, (3) aperture photometry, and (4) ALLSTAR profile-fitting photometry. We have included examples involving 21 frames for which either the sky brightness or image resolution varied by a factor of 3. The gains in S/N were modest for most of the examples, except for DAOFIND detection with varying image resolution which exhibited a substantial S/N increase. Even though the only consideration was maximizing S/N, the image resolution was seen to improve for most of the variable resolution examples. Also discussed are empirical fits for the weighting and the availability of the program, WEIGHT, used to generate the weighting for the individual frames. Finally, we include appendices describing the effects of clipping algorithms and a scheme for star/galaxy and cosmic-ray/star discrimination. scheme for star/galaxy and cosmic-ray/star discrimination.

  4. Integration of XNAT/PACS, DICOM, and research software for automated multi-modal image analysis

    NASA Astrophysics Data System (ADS)

    Gao, Yurui; Burns, Scott S.; Lauzon, Carolyn B.; Fong, Andrew E.; James, Terry A.; Lubar, Joel F.; Thatcher, Robert W.; Twillie, David A.; Wirt, Michael D.; Zola, Marc A.; Logan, Bret W.; Anderson, Adam W.; Landman, Bennett A.

    2013-03-01

    Traumatic brain injury (TBI) is an increasingly important public health concern. While there are several promising avenues of intervention, clinical assessments are relatively coarse and comparative quantitative analysis is an emerging field. Imaging data provide potentially useful information for evaluating TBI across functional, structural, and microstructural phenotypes. Integration and management of disparate data types are major obstacles. In a multi-institution collaboration, we are collecting electroencephalogy (EEG), structural MRI, diffusion tensor MRI (DTI), and single photon emission computed tomography (SPECT) from a large cohort of US Army service members exposed to mild or moderate TBI who are undergoing experimental treatment. We have constructed a robust informatics backbone for this project centered on the DICOM standard and eXtensible Neuroimaging Archive Toolkit (XNAT) server. Herein, we discuss (1) optimization of data transmission, validation and storage, (2) quality assurance and workflow management, and (3) integration of high performance computing with research software.

  5. MRI 3D CISS– A Novel Imaging Modality in Diagnosing Trigeminal Neuralgia – A Review

    PubMed Central

    Besta, Radhika; Shankar, Y. Uday; Kumar, Ashwini; Prakash, S. Bhanu

    2016-01-01

    Trigeminal Neuralgia (TN) is considered as one of the most painful neurologic disorders affecting oro-facial region. TN is often diagnosed clinically based on the patients complete history of pain (severity, duration, episodes etc), relief of pain on test dose of Carbamazepine, regional block of long acting anaesthetic. However, Magnetic Resonance Imaging (MRI) plays an important and confirmatory role in showing Neuro Vascular Conflict (NVC) which is the commonest causative factor for TN. This article reviews the effectiveness of three-dimensional constructive interference in steady-state (3D-CISS) MRI in diagnosing the exact location, degree of neurovascular conflict responsible for classical as well as atypical TN and possible pre-treatment evaluation and treatment outcome. PMID:27135019

  6. Integration of XNAT/PACS, DICOM, and Research Software for Automated Multi-modal Image Analysis

    PubMed Central

    Gao, Yurui; Burns, Scott S.; Lauzon, Carolyn B.; Fong, Andrew E.; James, Terry A.; Lubar, Joel F.; Thatcher, Robert W.; Twillie, David A.; Wirt, Michael D.; Zola, Marc A.; Logan, Bret W.; Anderson, Adam W.; Landman, Bennett A.

    2013-01-01

    Traumatic brain injury (TBI) is an increasingly important public health concern. While there are several promising avenues of intervention, clinical assessments are relatively coarse and comparative quantitative analysis is an emerging field. Imaging data provide potentially useful information for evaluating TBI across functional, structural, and microstructural phenotypes. Integration and management of disparate data types are major obstacles. In a multi-institution collaboration, we are collecting electroencephalogy (EEG), structural MRI, diffusion tensor MRI (DTI), and single photon emission computed tomography (SPECT) from a large cohort of US Army service members exposed to mild or moderate TBI who are undergoing experimental treatment. We have constructed a robust informatics backbone for this project centered on the DICOM standard and eXtensible Neuroimaging Archive Toolkit (XNAT) server. Herein, we discuss (1) optimization of data transmission, validation and storage, (2) quality assurance and workflow management, and (3) integration of high performance computing with research software. PMID:24386548

  7. Double jeopardy: multi-modality imaging of monozygotic "twin cap" atherosclerosis.

    PubMed

    Murray, Scott W; Cooper, Robert M; Appleby, Clare; McCann, Caroline; Binukrishnan, Sukumaran; Radu, Maria D; Stables, Rodney H

    2014-11-01

    The investigation of asymptomatic but potentially vulnerable atherosclerosis is not yet a major focus for clinical Cardiologists. We have illustrated the contemporary investigation and treatment of such disease using a clinical case that involved monozygotic twins. One twin (T1) had unfortunately suffered a cardiac arrest whilst jogging and survived only due to bystander CPR and prompt defibrillation. His identical twin brother (T2), on subsequent investigation, harbours a compositionally identical lesion in a proximal coronary vessel that has not yet ruptured or provoked a clinical event. Following the presentation of both non-invasive and invasive images, we discuss the need for active suspicion and intensive treatment for those people with a 'genetic' risk of future myocardial infarction.

  8. The Status of Contemporary Image-Guided Modalities in Oncologic Surgery

    PubMed Central

    Rosenthal, Eben L; Warram, Jason M; Bland, Kirby I; Zinn, Kurt R

    2014-01-01

    Surgical resection remains the cornerstone of therapy for patients with early stage solid malignancies and more than half of all cancer patients undergo surgery each year. The technical ability of the surgeon to obtain clear surgical margins at the initial resection remains crucial to improve overall survival and long-term morbidity. Current resection techniques are largely based on subjective and subtle changes associated with tissue distortion by invasive cancer. As a result, positive surgical margins occur in a significant portion of tumor resections, which is directly correlated with a poor outcome. A variety of cancer imaging techniques have been adapted or developed for intraoperative surgical guidance that have been shown to improve functional and oncologic outcomes in randomized clinical trials. There are also a large number of novel, cancer-specific contrast agents that are in early stage clinical trials and preclinical development that demonstrate significant promise to improve real-time detection of subclinical cancer in the operative setting. PMID:25599326

  9. Monitoring the clinical outcomes in advanced prostate cancer: what imaging modalities and other markers are reliable?

    PubMed

    Morris, Michael J; Autio, Karen A; Basch, Ethan M; Danila, Daniel C; Larson, Steven; Scher, Howard I

    2013-06-01

    Effective patient care and efficient drug development require accurate tools to assess treatment effects. For metastatic castration-resistant prostate cancer (mCRPC), response biomarkers have historically been poorly reproducible, inaccurate, inconsistently applied, or only loosely associated with tangible clinical benefits such as survival. However, the field of response assessments for prostate cancer is maturing, in compliance with a rigorous process defined by analytic validation, clinical validation, and clinical qualification. For example, bone imaging with technetium-99m scintigraphy has historically been poorly used in prostate cancer clinical trials and routine patient care, and frequently has led to poor decision-making. However, contemporary clinical trial consensus criteria (Prostate Cancer Working Group 2 [PCWG2]) have standardized the definition of progression on bone scintigraphy and the clinical trials endpoint of radiographic progression-free survival (rPFS). A validated bone scan interpretation form captures the relevant data elements. rPFS and the forms have been undergoing prospective testing in multiple phase III studies. The first of these trials demonstrated a high degree of reproducibility and correlation with overall survival, and rPFS was used by the US Food and Drug Administration (FDA) for approval of abiraterone in chemotherapy-naïve mCRPC. Circulating tumor cells (CTC) are another class of assays with significant promise as response-indicator biomarkers. CTC enumeration has undergone analytic validation and has been FDA-cleared for monitoring patients with prostate cancer in conjunction with other clinical methods. It is not yet a surrogate for survival. Patient-reported outcomes (PROs) are direct indicators of patient benefit. The assays to measure PROs must undergo each of the steps of biomarker development, and are increasingly being standardized and used as clinical trial endpoints. In this review, we critically assess each of

  10. Magnetically engineered Cd-free quantum dots as dual-modality probes for fluorescence/magnetic resonance imaging of tumors.

    PubMed

    Ding, Ke; Jing, Lihong; Liu, Chunyan; Hou, Yi; Gao, Mingyuan

    2014-02-01

    Magnetically engineered Cd-free CuInS2@ZnS:Mn quantum dots (QDs) were designed, synthesized, and evaluated as potential dual-modality probes for fluorescence and magnetic resonance imaging (MRI) of tumors in vivo. The synthesis of Mn-doped core-shell structured CuInS2@ZnS mainly comprised three steps, i.e., the preparation of fluorescent CuInS2 seeds, the particle surface coating of ZnS, and the Mn-doping of the ZnS shells. Systematic spectroscopy studies were carried out to illustrate the impacts of ZnS coating and the following Mn-doping on the optical properties of the QDs. In combination with conventional fluorescence, fluorescence excitation, and time-resolved fluorescence measurements, the structure of CuInS2@ZnS:Mn QDs prepared under optimized conditions presented a Zn gradient CuInS2 core and a ZnS outer shell, while Mn ions were mainly located in the ZnS shell, which well balanced the optical and magnetic properties of the resultant QDs. For the following in vivo imaging experiments, the hydrophobic CuInS2@ZnS:Mn QDs were transferred into water upon ligand exchange reactions by replacing the 1-dodecanethiol ligand with dihydrolipoic acid-poly(ethylene glycol) (DHLA-PEG) ligand. The MTT assays based on HeLa cells were carried out to evaluate the cytotoxicity of the current Cd-free CuInS2@ZnS:Mn QDs for comparing with that of water soluble CdTe QDs. Further in vivo fluorescence and MR imaging experiments suggested that the PEGylated CuInS2@ZnS:Mn QDs could well target both subcutaneous and intraperitoneal tumors in vivo.

  11. Spatial-temporal and modal analysis of propeller induced ground vortices by particle image velocimetry

    NASA Astrophysics Data System (ADS)

    Yang, Y.; Sciacchitano, A.; Veldhuis, L. L. M.; Eitelberg, G.

    2016-10-01

    During the ground operation of aircraft, there is potentially a system of vortices generated from the ground toward the propulsor, commonly denoted as ground vortices. Although extensive research has been conducted on ground vortices induced by turbofans which were simplified by suction tubes, these studies cannot well capture the properties of ground vortices induced by propellers, e.g., the flow phenomena due to intermittent characteristics of blade passing and the presence of slipstream of the propeller. Therefore, the investigation of ground vortices induced by a propeller is performed to improve understanding of these phenomena. The distributions of velocities in two different planes containing the vortices were measured by high frequency Particle Image Velocimetry. These planes are a wall-parallel plane in close proximity to the ground and a wall-normal plane upstream of the propeller. The instantaneous flow fields feature highly unsteady flow in both of these two planes. The spectral analysis is conducted in these two flow fields and the energetic frequencies are quantified. The flow fields are further evaluated by applying the Proper Orthogonal Decomposition analysis to capture the coherent flow structures. Consistent flow structures with strong contributions to the turbulent kinetic energy are noticed in the two planes.

  12. Enzyme-Mediated Modification of Single-Domain Antibodies for Imaging Modalities with Different Characteristics

    PubMed Central

    Edens, Jerre G.; Jacobsen, Johanne T.; Hossain, Intekhab; Wang, Qifan; Victora, Gabriel D.; Vasdev, Neil; Ploegh, Hidde; Liang, Steven H.

    2015-01-01

    Antibodies are currently the fastest-growing class of therapeutics. Although naked antibodies have proven valuable as pharmaceutical agents, they have some limitations, such as low tissue penetration and a long circulatory half-life. They have been conjugated to toxic payloads, PEGs, or radio-isotopes to increase and optimize their therapeutic efficacy. Although nonspecific conjugation is suitable for most in vitro applications, it has become evident that site specifically modified antibodies may have advantages for in vivo applications. Herein we describe a novel approach in which the antibody fragment is tagged with two handles: one for the introduction of a fluorophore or 18F isotope, and the second for further modification of the fragment with a PEG moiety or a second antibody fragment to tune its circulatory half-life or its avidity. Such constructs, which recognize Class II MHC products and CD11b, showed high avidity and specificity. They were used to image cancers and could detect small tumors. PMID:26630549

  13. Multi-modality imaging to assess metabolic response to dichloroacetate treatment in tumor models

    PubMed Central

    Neveu, Marie-Aline; Preter, Géraldine De; Joudiou, Nicolas; Bol, Anne; Brender, Jeffery R.; Saito, Keita; Kishimoto, Shun; Grégoire, Vincent; Jordan, Bénédicte F.; Krishna, Murali C.; Feron, Olivier; Gallez, Bernard

    2016-01-01

    Reverting glycolytic metabolism is an attractive strategy for cancer therapy as upregulated glycolysis is a hallmark in various cancers. Dichloroacetate (DCA), long used to treat lactic acidosis in various pathologies, has emerged as a promising anti-cancer drug. By inhibiting the pyruvate dehydrogenase kinase, DCA reactivates the mitochondrial function and decreases the glycolytic flux in tumor cells resulting in cell cycle arrest and apoptosis. We recently documented that DCA was able to induce a metabolic switch preferentially in glycolytic cancer cells, leading to a more oxidative phenotype and decreasing proliferation, while oxidative cells remained less sensitive to DCA treatment. To evaluate the relevance of this observation in vivo, the aim of the present study was to characterize the effect of DCA in glycolytic MDA-MB-231 tumors and in oxidative SiHa tumors using advanced pharmacodynamic metabolic biomarkers. Oxygen consumption, studied by 17O magnetic resonance spectroscopy, glucose uptake, evaluated by 18F-FDG PET and pyruvate transformation into lactate, measured using hyperpolarized 13C-magnetic resonance spectroscopy, were monitored before and 24 hours after DCA treatment in tumor bearing mice. In both tumor models, no clear metabolic shift was observed. Surprisingly, all these imaging parameters concur to the conclusion that both glycolytic tumors and oxidative tumors presented a similar response to DCA. These results highlight a major discordance in metabolic cancer cell bioenergetics between in vitro and in vivo setups, indicating critical role of the local microenvironment in tumor metabolic behaviors. PMID:28082726

  14. Monitoring the Spatiotemporal Activities of miRNAs in Small Animal Models Using Molecular Imaging Modalities

    PubMed Central

    Baril, Patrick; Ezzine, Safia; Pichon, Chantal

    2015-01-01

    MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression by binding mRNA targets via sequence complementary inducing translational repression and/or mRNA degradation. A current challenge in the field of miRNA biology is to understand the functionality of miRNAs under physiopathological conditions. Recent evidence indicates that miRNA expression is more complex than simple regulation at the transcriptional level. MiRNAs undergo complex post-transcriptional regulations such miRNA processing, editing, accumulation and re-cycling within P-bodies. They are dynamically regulated and have a well-orchestrated spatiotemporal localization pattern. Real-time and spatio-temporal analyses of miRNA expression are difficult to evaluate and often underestimated. Therefore, important information connecting miRNA expression and function can be lost. Conventional miRNA profiling methods such as Northern blot, real-time PCR, microarray, in situ hybridization and deep sequencing continue to contribute to our knowledge of miRNA biology. However, these methods can seldom shed light on the spatiotemporal organization and function of miRNAs in real-time. Non-invasive molecular imaging methods have the potential to address these issues and are thus attracting increasing attention. This paper reviews the state-of-the-art of methods used to detect miRNAs and discusses their contribution in the emerging field of miRNA biology and therapy. PMID:25749473

  15. Neutrons Image Additive Manufactured Turbine Blade in 3-D

    SciTech Connect

    2016-04-29

    The video displays the Inconel 718 Turbine Blade made by Additive Manufacturing. First a gray scale neutron computed tomogram (CT) is displays with transparency in order to show the internal structure. Then the neutron CT is overlapped with the engineering drawing that was used to print the part and a comparison of external and internal structures is possible. This provides a map of the accuracy of the printed turbine (printing tolerance). Internal surface roughness can also be observed.

  16. Multi-modality PET-CT imaging of breast cancer in an animal model using nanoparticle x-ray contrast agent and 18F-FDG

    NASA Astrophysics Data System (ADS)

    Badea, C. T.; Ghaghada, K.; Espinosa, G.; Strong, L.; Annapragada, A.

    2011-03-01

    Multi-modality PET-CT imaging is playing an important role in the field of oncology. While PET imaging facilitates functional interrogation of tumor status, the use of CT imaging is primarily limited to anatomical reference. In an attempt to extract comprehensive information about tumor cells and its microenvironment, we used a nanoparticle xray contrast agent to image tumor vasculature and vessel 'leakiness' and 18F-FDG to investigate the metabolic status of tumor cells. In vivo PET/CT studies were performed in mice implanted with 4T1 mammary breast cancer cells.Early-phase micro-CT imaging enabled visualization 3D vascular architecture of the tumors whereas delayedphase micro-CT demonstrated highly permeable vessels as evident by nanoparticle accumulation within the tumor. Both imaging modalities demonstrated the presence of a necrotic core as indicated by a hypo-enhanced region in the center of the tumor. At early time-points, the CT-derived fractional blood volume did not correlate with 18F-FDG uptake. At delayed time-points, the tumor enhancement in 18F-FDG micro-PET images correlated with the delayed signal enhanced due to nanoparticle extravasation seen in CT images. The proposed hybrid imaging approach could be used to better understand tumor angiogenesis and to be the basis for monitoring and evaluating anti-angiogenic and nano-chemotherapies.

  17. Evaluating the efficacy and safety of a novel endoscopic fluorescence imaging modality using oral 5-aminolevulinic acid for colorectal tumors

    PubMed Central

    Tsuruki, Eriko So; Saito, Yutaka; Abe, Seiichiro; Takamaru, Hiroyuki; Yamada, Masayoshi; Sakamoto, Taku; Nakajima, Takeshi; Matsuda, Takahisa; Sekine, Shigeki; Taniguchi, Hirokazu

    2016-01-01

    Background and study aims: Five-aminolevulinic acid (5-ALA) is being increasingly used for photodynamic diagnosis and therapy of various types of tumors including brain, urologic, and other neoplasias. The use of 5-ALA to treat Barrett’s carcinomas has been documented, but its clinical effectiveness for diagnosis of gastrointestinal tumors, particularly early cancers, remains unknown. Patients and methods: The aim of our feasibility study was to evaluate the visibility of colorectal tumors using endoscopic fluorescence imaging (EFI) after oral administration of 5-ALA. The lesions identified by direct visualization and by the spectrums produced using EFI modality with 5-ALA were compared to the clinicopathologic features of resected specimens. Results: Twenty-three patients with a total of 27 known colorectal lesions were enrolled in the study. The median tumor size was 30 mm (range 10 – 75). Eleven of the lesions were flat or depressed lesions and 16 were sessile. Red fluorescence was observed in 22 out of 27 lesions. Red fluorescence was negative in 4 out of 11 flat or depressed lesions. In comparison with histopathologic findings, the rates of red fluorescence visibility were 62.5 % in low-grade intraepithelial neoplasia, 77.8 % in high-grade neoplasia, and 100 % in submucosal carcinoma. Red fluorescence visibility increased with the degree of dysplasia. There were no significant adverse events identified in this study. Conclusions: This feasibility study using EFI with 5-ALA demonstrated high visibility of superficial colorectal neoplasia. EFI with 5-ALA appears to be a novel, safe technique for improving real-time colorectal tumor imaging. PMID:26793782

  18. Fingerprinting protocol for images based on additive homomorphic property.

    PubMed

    Kuribayashi, Minoru; Tanaka, Hatsukazu

    2005-12-01

    Homomorphic property of public-key cryptosystems is applied for several cryptographic protocols, such as electronic cash, voting system, bidding protocols, etc. Several fingerprinting protocols also exploit the property to achieve an asymmetric system. However, their enciphering rate is extremely low and the implementation of watermarking technique is difficult. In this paper, we propose a new fingerprinting protocol applying additive homomorphic property of Okamoto-Uchiyama encryption scheme. Exploiting the property ingenuously, the enciphering rate of our fingerprinting scheme can be close to the corresponding cryptosystem. We study the problem of implementation of watermarking technique and propose a successful method to embed an encrypted information without knowing the plain value. The security can also be protected for both a buyer and a merchant in our scheme.

  19. Co₉ Se₈ nanoplates as a new theranostic platform for photoacoustic/magnetic resonance dual-modal-imaging-guided chemo-photothermal combination therapy.

    PubMed

    Song, Xiao-Rong; Wang, Xiaoyong; Yu, Shu-Xian; Cao, Jianbo; Li, Shi-Hua; Li, Juan; Liu, Gang; Yang, Huang-Hao; Chen, Xiaoyuan

    2015-06-03

    A new theranostic platform is developed based on biocompatible poly(acrylic acid) (PAA)-Co9 Se8 nanoplates. These PAA-Co9 Se8 nanoplates are successfully utilized for photoacoustic imaging (PAI)/magnetic resonance imaging (MRI) dual-modal imaging. Moreover, the PAA-Co9 Se8 -DOX shows pH-responsive chemotherapy and enables the combination of photothermal therapy and chemotherapy to receive superior antitumor efficacy. This work promises further exploration of 2D nanoplatforms for theranostic applications.

  20. Gd (III) complex conjugate of low-molecular-weight chitosan as a contrast agent for magnetic resonance/fluorescence dual-modal imaging.

    PubMed

    Huang, Yan; Boamah, Peter Osei; Gong, Jianbo; Zhang, Qi; Hua, Mingqing; Ye, Yuzhen

    2016-06-05

    The fusion of molecular and anatomical modalities facilitates more reliable and accurate detection in clinic. In this work, we prepared gadolinium (III) complex Gd-DTPA-FITC-CS11 with magnetic resonance (MR) and fluorescence dual-modal imaging modalities. Gd-DTPA-FITC-CS11 consisted of fluorescein isothiocyanate and low-molecular-weight chitosan (CS11) units conjugated with gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA). Gd-DTPA-FITC-CS11 exhibited a higher longitudinal relaxivity (14.09 mM(-1)s(-1)) than the clinical Gd-DTPA (3.85 mM(-1)s(-1)). T1-weighted MR contrast enhancement was also demonstrated the comparability to Gd-DTPA at lower dosage. The binding with bovine serum albumin (BSA) was investigated. The fluorescence of BSA in the presence of Gd-DTPA-FITC-CS11 was weakened due to static quenching mechanism. The conformation of BSA was slightly changed but α-helix was dominant. The binding was entropy-driven and spontaneous and the main contribution was hydrophobic interaction. Our results suggested the potential of Gd-DTPA-FITC-CS11 as an MR/fluorescence dual-modal imaging contrast agent in improving the diagnostic sensitivity and accuracy.

  1. Phase-Transition Nanodroplets for Real-Time Photoacoustic/Ultrasound Dual-Modality Imaging and Photothermal Therapy of Sentinel Lymph Node in Breast Cancer

    PubMed Central

    Yang, Lu; Cheng, Juan; Chen, Yuli; Yu, Shengjie; Liu, Fengqiu; Sun, Yang; Chen, Yu; Ran, Haitao

    2017-01-01

    Pathological status of lymph nodes (LNs) plays a critical role in staging and treatment for the patients with breast cancer. Sentinel lymph node biopsy has become the standard method in determining pathological status of axillary LNs. Therefore, the determination of sentinel lymph nodes (SLNs) and therapy of metastatic LNs are highly desirable in clinic. Herein, an unprecedented carbon nanoparticles (CNs)-incorporated liquid-gas phase-transition nanodroplets (CNPs) with strong near-infrared (NIR) absorption, good biocompatibility, excellent photoacoustic (PA) and ultrasound (US) contrast, and high photothermal-conversion efficiency are reported in this study. Upon laser irradiation, liquid-gas phase transition of the CNPs has been demonstrated to provide excellent contrasts for PA/US dual-modality imaging both in vitro and in vivo. Additionally, the CNPs are capable of staining lymph nodes, which can contribute significantly to the identification of LNs with naked eyes. With increased laser energy, the CNPs exhibit the high performance in killing the breast cancer cells both in vitro and in vivo, due to the photothermal effect induced from the CNs within CNPs. These results suggest that the developed multifunctional phase-transition nanodroplets have high potential to act as the theranostic agents in both SLNs detection and therapy of metastatic LNs. PMID:28338071

  2. Terbium-doped gadolinium oxide nanoparticles prepared by laser ablation in liquid for use as a fluorescence and magnetic resonance imaging dual-modal contrast agent.

    PubMed

    Chen, Fei; Chen, Min; Yang, Chuan; Liu, Jun; Luo, Ningqi; Yang, Guowei; Chen, Dihu; Li, Li

    2015-01-14

    Dual-modal lanthanide-doped gadolinium nanoparticles (NPs), which exhibit an excellent magnetic resonance imaging (MRI) spatial resolution and high fluorescence imaging (FI) sensitivity, have attracted tremendous attention in biotechnology and nanomedicine applications. In this paper, terbium (Tb) ion doped gadolinium oxide (Gd2O3:Tb) NPs with varied Tb concentrations were synthesized by a laser ablation in liquid (LAL) method. The characterization of the structure, morphology, and composition shows that these NPs are spherical with excellent crystallinity. The effects of Tb ion concentration on the visible green fluorescence and longitudinal relaxivity were investigated, indicating that the fluorescence properties were significantly influenced by the Tb ion concentration, but all samples were still efficient T1-weighted contrast agents. Furthermore, the optimum Tb doping concentration was determined to be 1%. The cell viability, cellular fluorescence imaging and in vivo MRI of this dual-modal nano-probe were studied, with the results revealing that the Gd2O3:Tb NPs did not have a significant cytotoxic effect, making them good candidates for use as a dual-modal contrast agent for MRI and fluorescence imaging.

  3. Imaging modalities in keratoconus

    PubMed Central

    Matalia, Himanshu; Swarup, Rishi

    2013-01-01

    Diagnosis of keratoconus has greatly improved from simple clinical diagnosis with the advent of better diagnostic devices like corneal topographers based on placido disc, elevation based topographers and lately optical coherence tomography (OCT). These instruments are quite sensitive to pick up early keratoconus, which could help refractive surgeons to avoid serious complications like ectasia following keratorefractive surgeries. Each of these instruments has their advantages and disadvantages; in spite of that each one of them has its own place in the clinical practice. Currently, placido disc based topographers are the most commonly used topographers all over the world. There are many different companies making such devices, which follow the different techniques and color for the display. Due to these differences they are not directly comparable to each other. Various quantitative indices based on these topographers have been suggested and validated by different authors to aid in the diagnosis and quantification of keratoconus. OCT with its higher resolution and deeper penetration has created its place in the diagnostic armamentarium for keratoconus. PMID:23925322

  4. Combined multi-modal photoacoustic tomography, optical coherence tomography (OCT) and OCT angiography system with an articulated probe for in vivo human skin structure and vasculature imaging

    PubMed Central

    Liu, Mengyang; Chen, Zhe; Zabihian, Behrooz; Sinz, Christoph; Zhang, Edward; Beard, Paul C.; Ginner, Laurin; Hoover, Erich; Minneman, Micheal P.; Leitgeb, Rainer A.; Kittler, Harald; Drexler, Wolfgang

    2016-01-01

    Cutaneous blood flow accounts for approximately 5% of cardiac output in human and plays a key role in a number of a physiological and pathological processes. We show for the first time a multi-modal photoacoustic tomography (PAT), optical coherence tomography (OCT) and OCT angiography system with an articulated probe to extract human cutaneous vasculature in vivo in various skin regions. OCT angiography supplements the microvasculature which PAT alone is unable to provide. Co-registered volumes for vessel network is further embedded in the morphologic image provided by OCT. This multi-modal system is therefore demonstrated as a valuable tool for comprehensive non-invasive human skin vasculature and morphology imaging in vivo. PMID:27699106

  5. Superparamagnetic iron oxide nanoparticles function as a long-term, multi-modal imaging label for non-invasive tracking of implanted progenitor cells.

    PubMed

    Pacak, Christina A; Hammer, Peter E; MacKay, Allison A; Dowd, Rory P; Wang, Kai-Roy; Masuzawa, Akihiro; Sill, Bjoern; McCully, James D; Cowan, Douglas B

    2014-01-01

    The purpose of this study was to determine the ability of superparamagnetic iron oxide (SPIO) nanoparticles to function as a long-term tracking label for multi-modal imaging of implanted engineered tissues containing muscle-derived progenitor cells using magnetic resonance imaging (MRI) and X-ray micro-computed tomography (μCT). SPIO-labeled primary myoblasts were embedded in fibrin sealant and imaged to obtain intensity data by MRI or radio-opacity information by μCT. Each imaging modality displayed a detection gradient that matched increasing SPIO concentrations. Labeled cells were then incorporated in fibrin sealant, injected into the atrioventricular groove of rat hearts, and imaged in vivo and ex vivo for up to 1 year. Transplanted cells were identified in intact animals and isolated hearts using both imaging modalities. MRI was better able to detect minuscule amounts of SPIO nanoparticles, while μCT more precisely identified the location of heavily-labeled cells. Histological analyses confirmed that iron oxide particles were confined to viable, skeletal muscle-derived cells in the implant at the expected location based on MRI and μCT. These analyses showed no evidence of phagocytosis of labeled cells by macrophages or release of nanoparticles from transplanted cells. In conclusion, we established that SPIO nanoparticles function as a sensitive and specific long-term label for MRI and μCT, respectively. Our findings will enable investigators interested in regenerative therapies to non-invasively and serially acquire complementary, high-resolution images of transplanted cells for one year using a single label.

  6. A heart team and multi-modality imaging approach to percutaneous closure of a post-myocardial infarction ventricular septal defect

    PubMed Central

    Iyer, Sunil; Bauer, Thurston; Yeung, Michael; Ramm, Cassandra; Kiser, Andy C.; Caranasos, Thomas G.

    2016-01-01

    Post-infarction ventricular septal defect (PI-VSD) is a devastating complication that carries a high mortality with or without surgical repair. Percutaneous closure is an attractive alternative in select patients though requires appropriate characterization of the PI-VSD as well as careful device and patient selection. We describe a multidisciplinary and multi-modality imaging approach to successful percutaneous closure of a PI-VSD. PMID:27054108

  7. Calibration of remote mineralogy algorithms using modal analyses of Apollo soils by X-ray diffraction and microscopic spectral imaging

    NASA Astrophysics Data System (ADS)

    Crites, S. T.; Taylor, J.; Martel, L.; Lucey, P. G.; Blake, D. F.

    2012-12-01

    We have launched a project to determine the modal mineralogy of over 100 soils from all Apollo sites using quantitative X-ray diffraction (XRD) and microscopic hyperspectral imaging at visible, near-IR and thermal IR wavelengths. The two methods are complementary: XRD is optimal for obtaining the major mineral modes because its measurement is not limited to the surfaces of grains, whereas the hyperspectral imaging method allows us to identify minerals present even down to a single grain, well below the quantitative detection limit of XRD. Each soil is also sent to RELAB to obtain visible, near-IR, and thermal-IR reflectance spectra. The goal is to use quantitative mineralogy in comparison with spectra of the same soils and with remote sensing data of the sampling stations to improve our ability to extract quantitative mineralogy from remote sensing observations. Previous groups have demonstrated methods for using lab mineralogy to validate remote sensing. The LSCC pioneered the method of comparing mineralogy to laboratory spectra of the same soils (Pieters et al. 2002); Blewett et al. (1997) directly compared remote sensing results for sample sites with lab measurements of representative soils from those sites. We are building upon the work of both groups by expanding the number of soils measured to 128, with an emphasis on immature soils to support recent work studying fresh exposures like crater central peaks, and also by incorporating the recent high spatial and spectral resolution data sets over expanded wavelength ranges (e.g. Diviner TIR, M3 hyperspectral VNIR) not available at the time of the previous studies. We have thus far measured 32 Apollo 16 soils using quantitative XRD and are continuing with our collection of soils from the other landing sites. We have developed a microscopic spectral imaging system that includes TIR, VIS, and NIR capabilities and have completed proof-of-concept scans of mineral separates and preliminary lunar soil scans with plans

  8. Fluorescence and Magnetic Resonance Dual-Modality Imaging-Guided Photothermal and Photodynamic Dual-Therapy with Magnetic Porphyrin-Metal Organic Framework Nanocomposites

    PubMed Central

    Zhang, Hui; Li, Yu-Hao; Chen, Yang; Wang, Man-Man; Wang, Xue-Sheng; Yin, Xue-Bo

    2017-01-01

    Phototherapy shows some unique advantages in clinical application, such as remote controllability, improved selectivity, and low bio-toxicity, than chemotherapy. In order to improve the safety and therapeutic efficacy, imaging-guided therapy seems particularly important because it integrates visible information to speculate the distribution and metabolism of the probe. Here we prepare biocompatible core-shell nanocomposites for dual-modality imaging-guided photothermal and photodynamic dual-therapy by the in situ growth of porphyrin-metal organic framework (PMOF) on Fe3O4@C core. Fe3O4@C core was used as T2-weighted magnetic resonance (MR) imaging and photothermal therapy (PTT) agent. The optical properties of porphyrin were well remained in PMOF, and PMOF was therefore selected for photodynamic therapy (PDT) and fluorescence imaging. Fluorescence and MR dual-modality imaging-guided PTT and PDT dual-therapy was confirmed with tumour-bearing mice as model. The high tumour accumulation of Fe3O4@C@PMOF and controllable light excitation at the tumour site achieved efficient cancer therapy, but low toxicity was observed to the normal tissues. The results demonstrated that Fe3O4@C@PMOF was a promising dual-imaging guided PTT and PDT dual-therapy platform for tumour diagnosis and treatment with low cytotoxicity and negligible in vivo toxicity. PMID:28272454

  9. The multi-modal Australian ScienceS Imaging and Visualization Environment (MASSIVE) high performance computing infrastructure: applications in neuroscience and neuroinformatics research

    PubMed Central

    Goscinski, Wojtek J.; McIntosh, Paul; Felzmann, Ulrich; Maksimenko, Anton; Hall, Christopher J.; Gureyev, Timur; Thompson, Darren; Janke, Andrew; Galloway, Graham; Killeen, Neil E. B.; Raniga, Parnesh; Kaluza, Owen; Ng, Amanda; Poudel, Govinda; Barnes, David G.; Nguyen, Toan; Bonnington, Paul; Egan, Gary F.

    2014-01-01

    The Multi-modal Australian ScienceS Imaging and Visualization Environment (MASSIVE) is a national imaging and visualization facility established by Monash University, the Australian Synchrotron, the Commonwealth Scientific Industrial Research Organization (CSIRO), and the Victorian Partnership for Advanced Computing (VPAC), with funding from the National Computational Infrastructure and the Victorian Government. The MASSIVE facility provides hardware, software, and expertise to drive research in the biomedical sciences, particularly advanced brain imaging research using synchrotron x-ray and infrared imaging, functional and structural magnetic resonance imaging (MRI), x-ray computer tomography (CT), electron microscopy and optical microscopy. The development of MASSIVE has been based on best practice in system integration methodologies, frameworks, and architectures. The facility has: (i) integrated multiple different neuroimaging analysis software components, (ii) enabled cross-platform and cross-modality integration of neuroinformatics tools, and (iii) brought together neuroimaging databases and analysis workflows. MASSIVE is now operational as a nationally distributed and integrated facility for neuroinfomatics and brain imaging research. PMID:24734019

  10. Fluorescence and Magnetic Resonance Dual-Modality Imaging-Guided Photothermal and Photodynamic Dual-Therapy with Magnetic Porphyrin-Metal Organic Framework Nanocomposites

    NASA Astrophysics Data System (ADS)

    Zhang, Hui; Li, Yu-Hao; Chen, Yang; Wang, Man-Man; Wang, Xue-Sheng; Yin, Xue-Bo

    2017-03-01

    Phototherapy shows some unique advantages in clinical application, such as remote controllability, improved selectivity, and low bio-toxicity, than chemotherapy. In order to improve the safety and therapeutic efficacy, imaging-guided therapy seems particularly important because it integrates visible information to speculate the distribution and metabolism of the probe. Here we prepare biocompatible core-shell nanocomposites for dual-modality imaging-guided photothermal and photodynamic dual-therapy by the in situ growth of porphyrin-metal organic framework (PMOF) on Fe3O4@C core. Fe3O4@C core was used as T2-weighted magnetic resonance (MR) imaging and photothermal therapy (PTT) agent. The optical properties of porphyrin were well remained in PMOF, and PMOF was therefore selected for photodynamic therapy (PDT) and fluorescence imaging. Fluorescence and MR dual-modality imaging-guided PTT and PDT dual-therapy was confirmed with tumour-bearing mice as model. The high tumour accumulation of Fe3O4@C@PMOF and controllable light excitation at the tumour site achieved efficient cancer therapy, but low toxicity was observed to the normal tissues. The results demonstrated that Fe3O4@C@PMOF was a promising dual-imaging guided PTT and PDT dual-therapy platform for tumour diagnosis and treatment with low cytotoxicity and negligible in vivo toxicity.

  11. NSAID enteropathy: appearance at CT and MR enterography in the age of multi-modality imaging and treatment.

    PubMed

    Frye, Judson M; Hansel, Stephanie L; Dolan, Steven G; Fidler, Jeff L; Song, Louis M Wong Kee; Barlow, John M; Smyrk, Tom C; Flicek, Kristina T; Hara, Amy K; Bruining, David H; Fletcher, Joel G

    2015-06-01

    CT and MR enterography and capsule endoscopy are increasingly used as routine diagnostic tests for patients with potential small bowel disorders and obscure gastrointestinal bleeding. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used drugs that disrupt prostaglandin synthesis and result in a variety of localized complications within the small bowel ranging from ulcer formation to characteristic circumferential strictures, or diaphragms. NSAID enteropathy encompasses this spectrum of acute and chronic inflammatory sequelae, and is associated with typical findings at capsule endoscopy and surgery. Herein we review the typical clinical presentation of NSAID enteropathy, in addition to its endoscopic appearances, focusing on imaging findings at cross-sectional enterography. Multiple, short-segment strictures are the hallmarks of imaging diagnosis. Strictures may have minimal hyperenhancement or wall thickening, but these findings are typically symmetric and circumferential with respect to the bowel lumen. Multifocal Crohn's strictures, and occasionally radiation-induced strictures or adhesions, will mimic NSAID diaphragms. Multi-phase or multi-sequence imaging at CT and MR enterography increase diagnostic confidence in stricture presence. Strategies for subsequent workup and therapy after enterography are also discussed. Given the frequent use of NSAIDs and typical appearance of these strictures, knowledge of characteristic imaging findings can be particularly useful when evaluating patients with anemia and recurrent small bowel obstruction.

  12. Multi-modal Imaging of Angiogenesis in a Nude Rat Model of Breast Cancer Bone Metastasis Using Magnetic Resonance Imaging, Volumetric Computed Tomography and Ultrasound

    PubMed Central

    Bäuerle, Tobias; Komljenovic, Dorde; Berger, Martin R.; Semmler, Wolfhard

    2012-01-01

    , respectively. DCE-US allows for real-time imaging of vascularization in bone metastases after injection of microbubbles7. In conclusion, in a model of site-specific breast cancer bone metastases multi-modal imaging techniques including MRI, VCT and US offer complementary information on morphology and functional parameters of angiogenesis in these skeletal lesions. PMID:22929330

  13. Simultaneous capturing of RGB and additional band images using hybrid color filter array

    NASA Astrophysics Data System (ADS)

    Kiku, Daisuke; Monno, Yusuke; Tanaka, Masayuki; Okutomi, Masatoshi

    2014-03-01

    Extra band information in addition to the RGB, such as the near-infrared (NIR) and the ultra-violet, is valuable for many applications. In this paper, we propose a novel color filter array (CFA), which we call "hybrid CFA," and a demosaicking algorithm for the simultaneous capturing of the RGB and the additional band images. Our proposed hybrid CFA and demosaicking algorithm do not rely on any specific correlation between the RGB and the additional band. Therefore, the additional band can be arbitrarily decided by users. Experimental results demonstrate that our proposed demosaicking algorithm with the proposed hybrid CFA can provide the additional band image while keeping the RGB image almost the same quality as the image acquired by using the standard Bayer CFA.

  14. Diagnostic role of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for early and atypical bone metastases.

    PubMed

    Chen, Xiao-Liang; Li, Qian; Cao, Lin; Jiang, Shi-Xi

    2014-01-01

    The bone metastasis appeared early before the bone imaging for most of the above patients. (99)Tc(m)-MDP ((99)Tc(m) marked methylene diphosphonate) bone imaging could diagnosis the bone metastasis with highly sensitivity, but with lower specificity. The aim of this study is to explore the diagnostic value of (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging for the early period atypical bone metastases. 15 to 30 mCi (99)Tc(m)-MDP was intravenously injected to the 34 malignant patients diagnosed as doubtful early bone metastases. SPECT, CT and SPECT/CT images were captured and analyzed consequently. For the patients diagnosed as early period atypical bone metastases by SPECT/CT, combining the SPECT/CT and MRI together as the SPECT/MRI integrated image. The obtained SPECT/MRI image was analyzed and compared with the pathogenic results of patients. The results indicated that 34 early period doubtful metastatic focus, including 34 SPECT positive focus, 17 focus without special changes by using CT method, 11 bone metastases focus by using SPECT/CT method, 23 doubtful bone metastases focus, 8 doubtful bone metastases focus, 14 doubtful bone metastases focus and 2 focus without clear image. Totally, SPECT/CT combined with SPECT/MRI method diagnosed 30 bone metastatic focus and 4 doubtfully metastatic focus. In conclusion, (99)Tc(m)-MDP SPECT/CT combined SPECT/MRI Multi modality imaging shows a higher diagnostic value for the early period bone metastases, which also enhances the diagnostic accuracy rate.

  15. Comparison of dynamic contrast-enhanced MR, ultrasound and optical imaging modalities to evaluate the antiangiogenic effect of PF-03084014 and sunitinib

    PubMed Central

    Zhang, Cathy C; Yan, Zhengming; Giddabasappa, Anand; Lappin, Patrick B; Painter, Cory L; Zhang, Qin; Li, Gang; Goodman, James; Simmons, Brett; Pascual, Bernadette; Lee, Joseph; Levkoff, Ted; Nichols, Tim; Xie, Zhiyong

    2014-01-01

    Noninvasive imaging has been widely applied for monitoring antiangiogenesis therapy in cancer drug discovery. In this report, we used different imaging modalities including high-frequency ultrasound (HFUS), dynamic contrast enhanced-MR (DCE-MR), and fluorescence molecular tomography (FMT) imaging systems to monitor the changes in the tumor vascular properties after treatment with γ-secretase inhibitor PF-03084014. Sunitinib was tested in parallel for comparison. In the MDA-MB-231Luc model, we demonstrated that antiangiogenesis was one of the contributing mechanisms for the therapeutic effect of PF-03084014. By immunohistochemistry and FITC-lectin perfusion assays, we showed that the vascular defects upon treatment with PF-03084014 were associated with Notch pathway modulation, evidenced by a decrease in the HES1 protein and by the changes in VEGFR2 and HIF1α levels, which indicates down-stream effects. Using a 3D power Doppler scanning method, ultrasound imaging showed that the% vascularity in the MDA-MB-231Luc tumor decreased significantly at 4 and 7 days after the treatment with PF-03084014. A decrease in the tumor vessel function was also observed through contrast-enhanced ultrasound imaging with microbubble injection. These findings were consistent with the PF-03084014-induced functional vessel changes measured by suppressing the Ktrans values using DCE-MRI. In contrast, the FMT imaging with the AngioSence 680EX failed to detect any treatment-associated tumor vascular changes. Sunitinib demonstrated an outcome similar to PF-03084014 in the tested imaging modalities. In summary, ultrasound and DCE-MR imaging successfully provided longitudinal measurement of the phenotypic and functional changes in tumor vasculature after treatment with PF-03084014 and sunitinib. PMID:24573979

  16. A nanocomposite of Au-AgI core/shell dimer as a dual-modality contrast agent for x-ray computed tomography and photoacoustic imaging

    PubMed Central

    Orza, Anamaria; Yang, Yi; Feng, Ting; Wang, Xueding; Wu, Hui; Li, Yuancheng; Yang, Lily; Tang, Xiangyang; Mao, Hui

    2016-01-01

    Purpose: To develop a core/shell nanodimer of gold (core) and silver iodine (shell) as a dual-modal contrast-enhancing agent for biomarker targeted x-ray computed tomography (CT) and photoacoustic imaging (PAI) applications. Methods: The gold and silver iodine core/shell nanodimer (Au/AgICSD) was prepared by fusing together components of gold, silver, and iodine. The physicochemical properties of Au/AgICSD were then characterized using different optical and imaging techniques (e.g., HR- transmission electron microscope, scanning transmission electron microscope, x-ray photoelectron spectroscopy, energy-dispersive x-ray spectroscopy, Z-potential, and UV-vis). The CT and PAI contrast-enhancing effects were tested and then compared with a clinically used CT contrast agent and Au nanoparticles. To confer biocompatibility and the capability for efficient biomarker targeting, the surface of the Au/AgICSD nanodimer was modified with the amphiphilic diblock polymer and then functionalized with transferrin for targeting transferrin receptor that is overexpressed in various cancer cells. Cytotoxicity of the prepared Au/AgICSD nanodimer was also tested with both normal and cancer cell lines. Results: The characterizations of prepared Au/AgI core/shell nanostructure confirmed the formation of Au/AgICSD nanodimers. Au/AgICSD nanodimer is stable in physiological conditions for in vivo applications. Au/AgICSD nanodimer exhibited higher contrast enhancement in both CT and PAI for dual-modality imaging. Moreover, transferrin functionalized Au/AgICSD nanodimer showed specific binding to the tumor cells that have a high level of expression of the transferrin receptor. Conclusions: The developed Au/AgICSD nanodimer can be used as a potential biomarker targeted dual-modal contrast agent for both or combined CT and PAI molecular imaging. PMID:26745951

  17. A nanocomposite of Au-AgI core/shell dimer as a dual-modality contrast agent for x-ray computed tomography and photoacoustic imaging

    SciTech Connect

    Orza, Anamaria; Wu, Hui; Li, Yuancheng; Mao, Hui E-mail: Xiangyang.Tang@emory.edu; Yang, Yi; Tang, Xiangyang E-mail: Xiangyang.Tang@emory.edu; Feng, Ting; Wang, Xueding; Yang, Lily

    2016-01-15

    Purpose: To develop a core/shell nanodimer of gold (core) and silver iodine (shell) as a dual-modal contrast-enhancing agent for biomarker targeted x-ray computed tomography (CT) and photoacoustic imaging (PAI) applications. Methods: The gold and silver iodine core/shell nanodimer (Au/AgICSD) was prepared by fusing together components of gold, silver, and iodine. The physicochemical properties of Au/AgICSD were then characterized using different optical and imaging techniques (e.g., HR- transmission electron microscope, scanning transmission electron microscope, x-ray photoelectron spectroscopy, energy-dispersive x-ray spectroscopy, Z-potential, and UV-vis). The CT and PAI contrast-enhancing effects were tested and then compared with a clinically used CT contrast agent and Au nanoparticles. To confer biocompatibility and the capability for efficient biomarker targeting, the surface of the Au/AgICSD nanodimer was modified with the amphiphilic diblock polymer and then functionalized with transferrin for targeting transferrin receptor that is overexpressed in various cancer cells. Cytotoxicity of the prepared Au/AgICSD nanodimer was also tested with both normal and cancer cell lines. Results: The characterizations of prepared Au/AgI core/shell nanostructure confirmed the formation of Au/AgICSD nanodimers. Au/AgICSD nanodimer is stable in physiological conditions for in vivo applications. Au/AgICSD nanodimer exhibited higher contrast enhancement in both CT and PAI for dual-modality imaging. Moreover, transferrin functionalized Au/AgICSD nanodimer showed specific binding to the tumor cells that have a high level of expression of the transferrin receptor. Conclusions: The developed Au/AgICSD nanodimer can be used as a potential biomarker targeted dual-modal contrast agent for both or combined CT and PAI molecular imaging.

  18. Simultaneous synthesis and amine-functionalization of single-phase BaYF5:Yb/Er nanoprobe for dual-modal in vivo upconversion fluorescence and long-lasting X-ray computed tomography imaging

    NASA Astrophysics Data System (ADS)

    Liu, Hongrong; Lu, Wei; Wang, Haibo; Rao, Ling; Yi, Zhigao; Zeng, Songjun; Hao, Jianhua

    2013-06-01

    In this work, we developed a novel and biocompatible dual-modal nanoprobe based on single-phase amine-functionalized BaYF5:Yb/Er nanoparticles (NPs) for upconversion (UC) fluorescence and in vivo computed X-ray tomography (CT) bioimaging for the first time. High-quality water-soluble amine-functionalized BaYF5:Yb/Er NPs with an average size of 24 nm were synthesized by a facile environmentally friendly hydrothermal method for simultaneous synthesis and surface functionalization. Structure investigation based on the Rietveld refinement method revealed that the as-synthesized BaYF5:Yb/Er NPs present a cubic phase structure, which differs from the previously reported tetragonal structure. Under 980 nm excitation, high-contrast green and red UC emissions were observed from HeLa cells incubated with these amine-functionalized NPs. The UC spectra measured from the NPs incubated with HeLa cells presented only green and red UC emissions without any autofluorescence, further revealing that these NPs are ideal candidates for fluorescent bioimaging. In addition, the cell cytotoxicity test showed low cell toxicity of these NPs. These amine-functionalized NPs were also successfully used as CT agents for in vivo CT imaging because of the efficient X-ray absorption efficiency of Ba and doped Yb ions. A prolonged (2 h) signal enhancement of the spleen in a mouse was observed in CT imaging, which can improve the detection of splenic diseases. More importantly, the simultaneous X-ray and UC in vivo bioimaging was demonstrated in a nude mouse for the first time, indicating the as-prepared UCNPs can be successfully used as dual-modal bioprobes. These results demonstrate that BaYF5:Yb/Er NPs are ideal nanoprobes for dual-modal fluorescent/CT bioimaging with low cytotoxicity, non-autofluorescence, and enhanced detection of the spleen.

  19. India ink incorporated multifunctional phase-transition nanodroplets for photoacoustic/ultrasound dual-modality imaging and photoacoustic effect based tumor therapy.

    PubMed

    Jian, Jia; Liu, Chengbo; Gong, Yuping; Su, Lei; Zhang, Bin; Wang, Zhigang; Wang, Dong; Zhou, Yu; Xu, Fenfen; Li, Pan; Zheng, Yuanyi; Song, Liang; Zhou, Xiyuan

    2014-01-01

    The in vivo applications of gas-core microbubbles have been limited by gas diffusion, rapid body clearance, and poor vascular permeability. To overcome these limitations, using a modified three-step emulsion process, we have developed a first-of-its-kind India ink incorporated optically-triggerable phase-transition perfluorocarbon nanodroplets (INDs) that can provide not only three types of contrast mechanisms-conventional/thermoelastic photoacoustic, phase-transition/nonlinear photoacoustic, and ultrasound imaging contrasts, but also a new avenue for photoacoustic effect mediated tumor therapy. Upon pulsed laser illumination above a relatively low energy threshold, liquid-gas phase transition of the INDs has been demonstrated both in vitro and in vivo, offering excellent contrasts for photoacoustic and ultrasound dual-modality imaging. With further increased laser energy, the nanodroplets have been shown to be capable of destructing cancer cells in vivo, presumably due to the photoacoustic effect induced shock-wave generation from the carbon particles of the incorporated India ink. The demonstrated results suggest that the developed multifunctional phase-transition nanodroplets have a great potential for many theranostic biomedical applications, including photoacoustic/ultrasound dual-modality molecular imaging and targeted, localized cancer therapy.

  20. Gd-based upconversion nanocarriers with yolk-shell structure for dual-modal imaging and enhanced chemotherapy to overcome multidrug resistance in breast cancer

    NASA Astrophysics Data System (ADS)

    Pan, Yuanwei; Zhang, Ling'e.; Zeng, Leyong; Ren, Wenzhi; Xiao, Xueshan; Zhang, Jichao; Zhang, Lili; Li, Aiguo; Lu, Guangming; Wu, Aiguo

    2015-12-01

    Multidrug resistance (MDR) of cancers is still a major challenge, and it is very important to develop visualized nanoprobes for the diagnosis and treatment of drug resistant cancers. In this work, we developed a multifunctional delivery system based on DOX-encapsulated NaYF4:Yb/Er@NaGdF4 yolk-shell nanostructures for simultaneous dual-modal imaging and enhanced chemotherapy in drug resistant breast cancer. Using the large pore volume of the nanostructure, the delivery system had a high loading efficiency and excellent stability. Also, an in vitro and in vivo toxicity study showed the good biocompatibility of the as-prepared yolk-shell nanomaterials. Moreover, by nanocarrier delivery, the uptake of DOX could be greatly increased in drug resistant MCF-7/ADR cells. Compared with free DOX, the as-prepared delivery system enhanced the chemotherapy efficacy against MCF-7/ADR cells, indicating the excellent capability for overcoming MDR. Furthermore, core-shell NaYF4:Yb/Er@NaGdF4 improved the upconversion luminescence (UCL) performance, and the designed delivery system could also be applied for simultaneous UCL and magnetic resonance (MR) imaging, which could be a good candidate as a dual-modal imaging nanoprobe. Therefore, we developed a multifunctional yolk-shell delivery system, which could have potential applications as a visualized theranostic nanoprobe to overcome MDR in breast cancer.

  1. A Protein-Corona-Free T(1)-T(2) Dual-Modal Contrast Agent for Accurate Imaging of Lymphatic Tumor Metastasis.

    PubMed

    Zhou, Zijian; Liu, Hanyu; Chi, Xiaoqin; Chen, Jiahe; Wang, Lirong; Sun, Chengjie; Chen, Zhong; Gao, Jinhao

    2015-12-30

    Precise nodal staging is particularly important to guide the treatments and determine the prognosis for cancer patients. However, it is still challenging to noninvasively and precisely detect in-depth tumor metastasis in lymph nodes (LNs) because of the small size and high potential of obtaining pseudopositive results. Herein, we report the rational design of a T1-T2 dual-modal MRI contrast agent for accurate imaging of tumor metastasis in LNs using gadolinium-embedded iron oxide nanoplates (GdIOP). The GdIOP were modulated with suitable size in vivo through surface functionalization by zwitterionic dopamine sulfonate (ZDS) molecules. The efficient uptake of GdIOP@ZDS nanoparticles through drainage effect because of the presence of large amount of macrophages and dendritic cells generates both T1 and T2 contrasts in LNs. In contrast, the low uptake of protein-corona-free GdIOP@ZDS nanoparticles by melanoma B16 tumor cells promises pseudocontrast imaging of potential tumor metastasis in LNs. The combination of T1 and T2 imaging modalities allows self-confirmed detection of a metastatic tumor with about 1.2 mm in the minimal dimension in LNs, which is close to the detection limit of submilimeter level of MRI scans. This study provides an efficient and noninvasive strategy to detect tumor metastasis in LNs with greatly enhanced diagnostic accuracy.

  2. Comparing perceived auditory width to the visual image of a performing ensemble in contrasting bi-modal environmentsa)

    PubMed Central

    Valente, Daniel L.; Braasch, Jonas; Myrbeck, Shane A.

    2012-01-01

    Despite many studies investigating auditory spatial impressions in rooms, few have addressed the impact of simultaneous visual cues on localization and the perception of spaciousness. The current research presents an immersive audiovisual environment in which participants were instructed to make auditory width judgments in dynamic bi-modal settings. The results of these psychophysical tests suggest the importance of congruent audio visual presentation to the ecological interpretation of an auditory scene. Supporting data were accumulated in five rooms of ascending volumes and varying reverberation times. Participants were given an audiovisual matching test in which they were instructed to pan the auditory width of a performing ensemble to a varying set of audio and visual cues in rooms. Results show that both auditory and visual factors affect the collected responses and that the two sensory modalities coincide in distinct interactions. The greatest differences between the panned audio stimuli given a fixed visual width were found in the physical space with the largest volume and the greatest source distance. These results suggest, in this specific instance, a predominance of auditory cues in the spatial analysis of the bi-modal scene. PMID:22280585

  3. Biomass estimator for NIR image with a few additional spectral band images taken from light UAS

    NASA Astrophysics Data System (ADS)

    Pölönen, Ilkka; Salo, Heikki; Saari, Heikki; Kaivosoja, Jere; Pesonen, Liisa; Honkavaara, Eija

    2012-05-01

    A novel way to produce biomass estimation will offer possibilities for precision farming. Fertilizer prediction maps can be made based on accurate biomass estimation generated by a novel biomass estimator. By using this knowledge, a variable rate amount of fertilizers can be applied during the growing season. The innovation consists of light UAS, a high spatial resolution camera, and VTT's novel spectral camera. A few properly selected spectral wavelengths with NIR images and point clouds extracted by automatic image matching have been used in the estimation. The spectral wavelengths were chosen from green, red, and NIR channels.

  4. Translation of modality database entries to an ACR-NEMA transfer syntax

    NASA Astrophysics Data System (ADS)

    Chimiak, William J.; Williams, Rodney C.

    1993-09-01

    Picker MR images were translated to the Bowman Gray School of Medicine (BGSM) IMACS format using software designed for portability to other modalities. The Siemens PET modality was the first successful test of the software's extensibility. Although the Picker project took nine months to complete, the Siemens project took only about two months. The structures of the Siemens PET images are organized utilizing software constructs which made the translation even easier. In addition, the Siemens PET system used standard Unix workstations with the Network File System (NFS), TCP/IP, and X Windows which greatly facilitated the transport of images. The translation of GE 9800 CT modality images, using a PBT interface allowed images to be sent to the 9-track archive system or the network using a state of the art NFS mount. This permitted using many powerful tools available on most Unix machines such as the qsh software developed by Gerald Q. Maguire Jr. and Marilyn E. Noz for the translation of various modalities into their DICOM-based key-value-pair system. This provided a mechanism for modality data base translation. In this way, it is hoped that modality images can be sent effectively to our IMACS. This paper discusses the transmission and conversion of modality database entries (images and demographics) into the BGSM DICOM format.

  5. Targeting T1 and T2 dual modality enhanced magnetic resonance imaging of tumor vascular endothelial cells based on peptides-conjugated manganese ferrite nanomicelles

    PubMed Central

    Gong, Mingfu; Yang, Hua; Zhang, Song; Yang, Yan; Zhang, Dong; Li, Zhaohui; Zou, Liguang

    2016-01-01

    Tumor angiogenesis plays very important roles for tumorigenesis, tumor development, metastasis, and prognosis. Targeting T1/T2 dual modality magnetic resonance (MR) imaging of the tumor vascular endothelial cells (TVECs) with MR molecular probes can greatly improve diagnostic sensitivity and specificity, as well as helping to make an early diagnosis of tumor at the preclinical stage. In this study, a new T1 and T2 dual modality nanoprobe was successfully fabricated. The prepared nanoprobe comprise peptides CL 1555, poly(ε-caprolactone)-block-poly(ethylene glycol) amphiphilic copolymer shell, and dozens of manganese ferrite (MnFe2O4) nanoparticle core. The results showed that the hydrophobic MnFe2O4 nanoparticles were of uniform spheroidal appearance and narrow size distribution. Due to the self-assembled nanomicelles structure, the prepared probes were of high relaxivity of 281.7 mM−1 s−1, which was much higher than that of MnFe2O4 nanoparticles (67.5 mM 1 s−1). After being grafted with the targeted CD105 peptide CL 1555, the nanomicelles can combine TVECs specifically and make the labeled TVECs dark in T2-weighted MR imaging. With the passage on, the Mn2+ ions were released from MnFe2O4 and the size decreased gradually, making the signal intensity of the second and third passage of labeled TVECs increased in T1-weighted MR imaging. Our results demonstrate that CL-poly(ethylene glycol)-MnFe2O4 can conjugate TVECs and induce dark and bright contrast in MR imaging, and act as a novel molecular probe for T1- and T2-enhanced MR imaging of tumor angiogenesis. PMID:27578974

  6. An automated multi-modal object analysis approach to coronary calcium scoring of adaptive heart isolated MSCT images

    NASA Astrophysics Data System (ADS)

    Wu, Jing; Ferns, Gordon; Giles, John; Lewis, Emma

    2012-02-01

    Inter- and intra- observer variability is a problem often faced when an expert or observer is tasked with assessing the severity of a disease. This issue is keenly felt in coronary calcium scoring of patients suffering from atherosclerosis where in clinical practice, the observer must identify firstly the presence, followed by the location of candidate calcified plaques found within the coronary arteries that may prevent oxygenated blood flow to the heart muscle. This can be challenging for a human observer as it is difficult to differentiate calcified plaques that are located in the coronary arteries from those found in surrounding anatomy such as the mitral valve or pericardium. The inclusion or exclusion of false positive or true positive calcified plaques respectively will alter the patient calcium score incorrectly, thus leading to the possibility of incorrect treatment prescription. In addition to the benefits to scoring accuracy, the use of fast, low dose multi-slice CT imaging to perform the cardiac scan is capable of acquiring the entire heart within a single breath hold. Thus exposing the patient to lower radiation dose, which for a progressive disease such as atherosclerosis where multiple scans may be required, is beneficial to their health. Presented here is a fully automated method for calcium scoring using both the traditional Agatston method, as well as the Volume scoring method. Elimination of the unwanted regions of the cardiac image slices such as lungs, ribs, and vertebrae is carried out using adaptive heart isolation. Such regions cannot contain calcified plaques but can be of a similar intensity and their removal will aid detection. Removal of both the ascending and descending aortas, as they contain clinical insignificant plaques, is necessary before the final calcium scores are calculated and examined against ground truth scores of three averaged expert observer results. The results presented here are intended to show the requirement and

  7. A fully automated multi-modal computer aided diagnosis approach to coronary calcium scoring of MSCT images

    NASA Astrophysics Data System (ADS)

    Wu, Jing; Ferns, Gordon; Giles, John; Lewis, Emma

    2012-03-01

    Inter- and intra- observer variability is a problem often faced when an expert or observer is tasked with assessing the severity of a disease. This issue is keenly felt in coronary calcium scoring of patients suffering from atherosclerosis where in clinical practice, the observer must identify firstly the presence, followed by the location of candidate calcified plaques found within the coronary arteries that may prevent oxygenated blood flow to the heart muscle. However, it can be difficult for a human observer to differentiate calcified plaques that are located in the coronary arteries from those found in surrounding anatomy such as the mitral valve or pericardium. In addition to the benefits to scoring accuracy, the use of fast, low dose multi-slice CT imaging to perform the cardiac scan is capable of acquiring the entire heart within a single breath hold. Thus exposing the patient to lower radiation dose, which for a progressive disease such as atherosclerosis where multiple scans may be required, is beneficial to their health. Presented here is a fully automated method for calcium scoring using both the traditional Agatston method, as well as the volume scoring method. Elimination of the unwanted regions of the cardiac image slices such as lungs, ribs, and vertebrae is carried out using adaptive heart isolation. Such regions cannot contain calcified plaques but can be of a similar intensity and their removal will aid detection. Removal of both the ascending and descending aortas, as they contain clinical insignificant plaques, is necessary before the final calcium scores are calculated and examined against ground truth scores of three averaged expert observer results. The results presented here are intended to show the feasibility and requirement for an automated scoring method to reduce the subjectivity and reproducibility error inherent with manual clinical calcium scoring.

  8. A Three-Step Approach with Adaptive Additive Magnitude Selection for the Sharpening of Images

    PubMed Central

    Lee, Tien-Lin

    2014-01-01

    Aimed to find the additive magnitude automatically and adaptively, we propose a three-step and model-based approach for the sharpening of images in this paper. In the first pass, a Grey prediction model is applied to find a global maximal additive magnitude so that the condition of oversharpening in images to be sharpened can be avoided. During the second pass, edge pixels are picked out with our previously proposed edge detection mechanism. In this pass, a low-pass filter is also applied so that isolated pixels will not be regarded as around an edge. In the final pass, those pixels detected as around an edge are adjusted adaptively based on the local statistics, and those nonedge pixels are kept unaltered. Extensive experiments on natural images as well as medical images with subjective and objective evaluations will be given to demonstrate the usefulness of the proposed approach. PMID:25309951

  9. Hydrothermal synthesis of BaYbF5:Tm3+ nanoparticles for dual-modal upconversion near-infrared luminescence and magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Liu, Ping; Miu, Wei

    2016-04-01

    In this paper, we demonstrate multifunctional upconversion nanoparticles with intense near-infrared emission and unique magnetic properties for dual-modal upconversion luminescent bioimaging and T2-weighted magnetic resonance imaging. High-quality BaYbF5:Tm3+ nanoparticles are synthesized via a hydrophobic method and then converted to be hydrophilic via a hydrochloric acid treatment. The as-synthesized nanoparticles are cubic phase and about 6 nm in diameter with narrow size distribution. The intense near-infrared emission makes these nanoparticles can be acted as bio-probes in upconversion luminescent bioimaging with deep tissue penetration. Besides, these nanoparticles can also be used as T2-weighted contrast agents in magnetic resonance imaging due to the high value of relaxation rate (r2 = 4.05) in 0.55 T. This finding may have further bio-applications in the future due to the high performance of these BaYbF5:Tm3+ nanoparticles in dual-modal bioimaging.

  10. Monitoring the Growth of an Orthotopic Tumour Xenograft Model: Multi-Modal Imaging Assessment with Benchtop MRI (1T), High-Field MRI (9.4T), Ultrasound and Bioluminescence

    PubMed Central

    Stuckey, Daniel J.; David, Anna L.; Pedley, R. Barbara; Lythgoe, Mark F.; Siow, Bernard; Walker-Samuel, Simon

    2016-01-01

    Background Research using orthotopic and transgenic models of cancer requires imaging methods to non-invasively quantify tumour burden. As the choice of appropriate imaging modality is wide-ranging, this study aimed to compare low-field (1T) magnetic resonance imaging (MRI), a novel and relatively low-cost system, against established preclinical techniques: bioluminescence imaging (BLI), ultrasound imaging (US), and high-field (9.4T) MRI. Methods A model of colorectal metastasis to the liver was established in eight mice, which were imaged with each modality over four weeks post-implantation. Tumour burden was assessed from manually segmented regions. Results All four imaging systems provided sufficient contrast to detect tumours in all of the mice after two weeks. No significant difference was detected between tumour doubling times estimated by low-field MRI, ultrasound imaging or high-field MRI. A strong correlation was measured between high-field MRI estimates of tumour burden and all the other modalities (p < 0.001, Pearson). Conclusion These results suggest that both low-field MRI and ultrasound imaging are accurate modalities for characterising the growth of preclinical tumour models. PMID:27223614

  11. Dual-Modality Imaging of the Human Finger Joint Systems by Using Combined Multispectral Photoacoustic Computed Tomography and Ultrasound Computed Tomography

    PubMed Central

    Liu, Yubin; Wang, Yating

    2016-01-01

    We developed a homemade dual-modality imaging system that combines multispectral photoacoustic computed tomography and ultrasound computed tomography for reconstructing the structural and functional information of human finger joint systems. The fused multispectral photoacoustic-ultrasound computed tomography (MPAUCT) system was examined by the phantom and in vivo experimental tests. The imaging results indicate that the hard tissues such as the bones and the soft tissues including the blood vessels, the tendon, the skins, and the subcutaneous tissues in the finger joints systems can be effectively recovered by using our multimodality MPAUCT system. The developed MPAUCT system is able to provide us with more comprehensive information of the human finger joints, which shows its potential for characterization and diagnosis of bone or joint diseases. PMID:27774453

  12. Incidental vesicocolic fistula on routine bone scintigraphy: Value of additional delayed images and direct radionuclide cystography.

    PubMed

    Sohn, Myung-Hee; Tae Lim, Seok; Jin Jeong, Young; Wook Kim, Dong; Jeong, Hwan-Jeong; Yim, Chang-Yeol

    2010-09-01

    An unexpected vesicocolic fistula can be detected incidentally on routine bone scintigraphy. A 55-year-old man who had a radical colectomy for carcinoma of the sigmoid colon 1 year previously underwent bone scintigraphy to evaluate bone metastasis. Whole-body images showed an abnormal accumulation of radioactivity in the right lower quadrant of the abdomen, but the radioactivity did not precisely define a structure. Additional delayed images obtained after 15 and 24 hours of the initial image localized a vesicocolic fistula. Subsequent radionuclide cystography confirmed leakage of the radioactivity from the bladder.

  13. Cone-Beam CT-Based Delineation of Stereotactic Lung Targets: The Influence of Image Modality and Target Size on Interobserver Variability

    SciTech Connect

    Altorjai, Gabriela

    2012-02-01

    Purpose: It is generally agreed that the safe implementation of stereotactic body radiotherapy requires image guidance. The aim of this work was to assess interobserver variability in the delineation of lung lesions on cone-beam CT (CBCT) images compared with CT-based contouring for adaptive stereotactic body radiotherapy. The influence of target size was also evaluated. Methods and Materials: Eight radiation oncologists delineated gross tumor volumes in 12 patient cases (non-small cell lung cancer I-II or solitary metastasis) on planning CTs and on CBCTs. Cases were divided into two groups with tumor diameters of less than (Group A) or more than 2 cm (Group B). Comparison of mean volumes delineated by all observers and range and coefficient of variation were reported for each case and image modality. Interobserver variability was assessed by means of standard error of measurement, conformity index (CI), and its generalized observer-independent approach. The variance between single observers on CT and CBCT images was measured via interobserver reliability coefficient. Results: Interobserver variability on CT images was 17% with 0.79 reliability, compared with 21% variability on CBCT and 0.76 reliability. On both image modalities, values of the intraobserver reliability coefficient (0.99 for CT and 0.97 for CBCT) indicated high reproducibility of results. In general, lower interobserver agreement was observed for small lesions (CI{sub genA} = 0.62 {+-} 0.06 vs. CI{sub genB} = 0.70 {+-} 0.03, p < 0.05). The analysis of single patient cases revealed that presence of spicules, diffuse infiltrations, proximity of the tumors to the vessels and thoracic wall, and respiration motion artifacts presented the main sources of the variability. Conclusion: Interobserver variability for Stage I-II non-small cell lung cancer and lung metastasis was slightly higher on CBCT compared with CT. Absence of significant differences in interobserver variability suggests that CBCT imaging

  14. In Vivo Magnetic Resonance and Fluorescence Dual-Modality Imaging of Tumor Angiogenesis in Rats Using GEBP11 Peptide Targeted Magnetic Nanoparticles.

    PubMed

    Su, Tao; Wang, Yabin; Wang, Jiinda; Han, Dong; Ma, Sai; Cao, Jianbo; Li, Xiujuan; Zhang, Ran; Qiao, Hongyu; Liang, Jimin; Liu, Gang; Yang, Bo; Liang, Shuhui; Nie, Yongzhan; Wu, Kaichun; Li, Jiayi; Cao, Feng

    2016-05-01

    Angiogenesis is an essential process for tumor progression. Tumor vasculature-targeting peptides have shown great potential for use in cancer imaging and therapy. Our previous studies have shown that GEBP11, a novel vasculature-specific binding peptide that exhibits high affinity and specificity to tumor angiogenesis, is a promising candidate for the diagnosis and targeted radiotherapy of gastric cancer. In the present study, we developed a novel magnetic resonance and fluorescence (MR/Fluo) dual-modality imaging probe by covalently coupling 2,3-dimercaptosuccinnic acid-coated paramagnetic nanoparticles (DMSA-MNPs) and Cy5.5 to the GEBP11 peptide. The probe Cy5.5-GEBP11-DMSA-MNPs (CGD-MNPs), with a hydrodynamic diameter of 82.8 ± 6.5 nm, exhibited good imaging properties, high stability and little cytotoxicity. In vivo MR/Fluo imaging revealed that CGD-MNPs were successfully applied to visualize tumor angiogenesis in SGC-7901 xenograft mouse models. Prussian blue and CD31 immunohistochemical staining confirmed that CGD-MNPs co-localized with tumor blood vessels. In conclusion, CGD-MNPs are promising candidates for use as MR and fluorescence imaging probes for visualizing gastric cancer angiogenesis in vivo.

  15. Characterization of silver halide fiber for modal filtering on mid-infrared: imaging, nulling, and spectral transmission

    NASA Astrophysics Data System (ADS)

    Grille, R.; Labadie, L.; Kern, P.; Martin, G.; Arezki, B.

    2008-07-01

    One of the critical issues for nulling interferometry breadboards for exo-earth detection relies on the possibility to manufacture and properly characterize optical waveguides that present suitable single mode behaviors in the foreseen spectral range (4-20 μm). We developed a dedicated bench for the characterization of available guides for the considered spectral range, in particulary silver halide fibers. This interferometric bench achieves modal characterization in nulling mode and spectral transmission in Fourier Transform spectrometer mode, defining the single mode domain of the components. We present the experimental setup and its performances. We present also some characterization of their single-mode behavior according to the injection conditions. These measurements are very useful for the conception of optimized components.

  16. Magnetic and fluorescent Gd2O3:Yb(3+)/Ln(3+) nanoparticles for simultaneous upconversion luminescence/MR dual modal imaging and NIR-induced photodynamic therapy.

    PubMed

    Liu, Jun; Huang, Long; Tian, Xiumei; Chen, Xiaoming; Shao, Yuanzhi; Xie, Fukang; Chen, Dihu; Li, Li

    The development of upconversion nanoparticles (UCNs) for theranostics application is a new strategy toward the accurate diagnosis and efficient treatment of cancer. Here, magnetic and fluorescent lanthanide-doped gadolinium oxide (Gd2O3) UCNs with bright upconversion luminescence (UCL) and high longitudinal relaxivity (r1) are used for simultaneous magnetic resonance imaging (MRI)/UCL dual-modal imaging and photodynamic therapy (PDT). In vitro and in vivo MRI studies show that these products can serve as good MRI contrast agents. The bright upconversion luminescence of the products allows their use as fluorescence nanoprobes for live cells imaging. We also utilized the luminescence-emission capability of the UCNs for the activation of a photosensitizer to achieve significant PDT results. To the best of our knowledge, this study is the first use of lanthanide-doped Gd2O3 UCNs in a theranostics application. This investigation provides a useful platform for the development of Gd2O3-based UCNs for clinical diagnosis, treatment, and imaging-guided therapy of cancer.

  17. Magnetic and fluorescent Gd2O3:Yb3+/Ln3+ nanoparticles for simultaneous upconversion luminescence/MR dual modal imaging and NIR-induced photodynamic therapy

    PubMed Central

    Liu, Jun; Huang, Long; Tian, Xiumei; Chen, Xiaoming; Shao, Yuanzhi; Xie, Fukang; Chen, Dihu; Li, Li

    2017-01-01

    The development of upconversion nanoparticles (UCNs) for theranostics application is a new strategy toward the accurate diagnosis and efficient treatment of cancer. Here, magnetic and fluorescent lanthanide-doped gadolinium oxide (Gd2O3) UCNs with bright upconversion luminescence (UCL) and high longitudinal relaxivity (r1) are used for simultaneous magnetic resonance imaging (MRI)/UCL dual-modal imaging and photodynamic therapy (PDT). In vitro and in vivo MRI studies show that these products can serve as good MRI contrast agents. The bright upconversion luminescence of the products allows their use as fluorescence nanoprobes for live cells imaging. We also utilized the luminescence-emission capability of the UCNs for the activation of a photosensitizer to achieve significant PDT results. To the best of our knowledge, this study is the first use of lanthanide-doped Gd2O3 UCNs in a theranostics application. This investigation provides a useful platform for the development of Gd2O3-based UCNs for clinical diagnosis, treatment, and imaging-guided therapy of cancer. PMID:28031709

  18. Miniature device for chronic, label-free multi-modal optical imaging of cortical hemodynamics in rats

    NASA Astrophysics Data System (ADS)

    Gad, Raanan; Sigal, Iliya; Ringuette, Dene; Koletar, Margaret; Stefanovic, Bojana; Levi, Ofer

    2015-03-01

    We report on a novel miniature head-mounted imaging system for simultaneous optical recording of brain blood flow and changes in brain blood oxygenation in a rat. Measurements of blood flow speeds are accomplished using Laser Speckle Contrast Imaging (LSCI) technique, while changes in blood oxygenation are measured via Intrinsic Optical Signal Imaging (IOSI) technique. A single multi-wavelength (wavelength = 680, 795, 850 nm) package of vertical cavity surface emitting lasers (VCSELs) is used as the sole brain illumination source. VCSELs enable rapid toggling between wavelengths, and between high-coherence and low-coherence modes, necessary for LSCI and IOSI, respectively. The combination of a miniature light source and a small 10-bit CCD camera sensor lead to a sub-20 g device mass. The miniature imaging system, including the lens, camera, and illumination lasers, is packaged as a module, and is mounted on a chronic implanted observation window that is surgically placed in the skull, allowing for repeated measurements and removal of the imaging system from the rats head after the imaging session. The imaging system allows for a 2mm-diameter field of view and a resolution of 7.4 µm. It will allow neurophysiologists to correlate standard behavioural assays to neurovascular response in animal models, and thus enrich their understanding of neurovascular coupling dynamics of brain disorders and diseases such as stroke and epilepsy.

  19. Open framework for management and processing of multi-modality and multidimensional imaging data for analysis and modelling muscular function

    NASA Astrophysics Data System (ADS)

    García Juan, David; Delattre, Bénédicte M. A.; Trombella, Sara; Lynch, Sean; Becker, Matthias; Choi, Hon Fai; Ratib, Osman

    2014-03-01

    Musculoskeletal disorders (MSD) are becoming a big healthcare economical burden in developed countries with aging population. Classical methods like biopsy or EMG used in clinical practice for muscle assessment are invasive and not accurately sufficient for measurement of impairments of muscular performance. Non-invasive imaging techniques can nowadays provide effective alternatives for static and dynamic assessment of muscle function. In this paper we present work aimed toward the development of a generic data structure for handling n-dimensional metabolic and anatomical data acquired from hybrid PET/MR scanners. Special static and dynamic protocols were developed for assessment of physical and functional images of individual muscles of the lower limb. In an initial stage of the project a manual segmentation of selected muscles was performed on high-resolution 3D static images and subsequently interpolated to full dynamic set of contours from selected 2D dynamic images across different levels of the leg. This results in a full set of 4D data of lower limb muscles at rest and during exercise. These data can further be extended to a 5D data by adding metabolic data obtained from PET images. Our data structure and corresponding image processing extension allows for better evaluation of large volumes of multidimensional imaging data that are acquired and processed to generate dynamic models of the moving lower limb and its muscular function.

  20. Dual-modal three-dimensional imaging of single cells with isometric high resolution using an optical projection tomography microscope

    NASA Astrophysics Data System (ADS)

    Miao, Qin; Rahn, J. Richard; Tourovskaia, Anna; Meyer, Michael G.; Neumann, Thomas; Nelson, Alan C.; Seibel, Eric J.

    2009-11-01

    The practice of clinical cytology relies on bright-field microscopy using absorption dyes like hematoxylin and eosin in the transmission mode, while the practice of research microscopy relies on fluorescence microscopy in the epi-illumination mode. The optical projection tomography microscope is an optical microscope that can generate 3-D images of single cells with isometric high resolution both in absorption and fluorescence mode. Although the depth of field of the microscope objective is in the submicron range, it can be extended by scanning the objective's focal plane. The extended depth of field image is similar to a projection in a conventional x-ray computed tomography. Cells suspended in optical gel flow through a custom-designed microcapillary. Multiple pseudoprojection images are taken by rotating the microcapillary. After these pseudoprojection images are further aligned, computed tomography methods are applied to create 3-D reconstruction. 3-D reconstructed images of single cells are shown in both absorption and fluorescence mode. Fluorescence spatial resolution is measured at 0.35 μm in both axial and lateral dimensions. Since fluorescence and absorption images are taken in two different rotations, mechanical error may cause misalignment of 3-D images. This mechanical error is estimated to be within the resolution of the system.

  1. Development of a multi-scale and multi-modality imaging system to characterize tumours and their microenvironment in vivo

    NASA Astrophysics Data System (ADS)

    Rouffiac, Valérie; Ser-Leroux, Karine; Dugon, Emilie; Leguerney, Ingrid; Polrot, Mélanie; Robin, Sandra; Salomé-Desnoulez, Sophie; Ginefri, Jean-Christophe; Sebrié, Catherine; Laplace-Builhé, Corinne

    2015-03-01

    In vivo high-resolution imaging of tumor development is possible through dorsal skinfold chamber implantable on mice model. However, current intravital imaging systems are weakly tolerated along time by mice and do not allow multimodality imaging. Our project aims to develop a new chamber for: 1- long-term micro/macroscopic visualization of tumor (vascular and cellular compartments) and tissue microenvironment; and 2- multimodality imaging (photonic, MRI and sonography). Our new experimental device was patented in March 2014 and was primarily assessed on 75 mouse engrafted with 4T1-Luc tumor cell line, and validated in confocal and multiphoton imaging after staining the mice vasculature using Dextran 155KDa-TRITC or Dextran 2000kDa-FITC. Simultaneously, a universal stage was designed for optimal removal of respiratory and cardiac artifacts during microscopy assays. Experimental results from optical, ultrasound (Bmode and pulse subtraction mode) and MRI imaging (anatomic sequences) showed that our patented design, unlike commercial devices, improves longitudinal monitoring over several weeks (35 days on average against 12 for the commercial chamber) and allows for a better characterization of the early and late tissue alterations due to tumour development. We also demonstrated the compatibility for multimodality imaging and the increase of mice survival was by a factor of 2.9, with our new skinfold chamber. Current developments include: 1- defining new procedures for multi-labelling of cells and tissue (screening of fluorescent molecules and imaging protocols); 2- developing ultrasound and MRI imaging procedures with specific probes; 3- correlating optical/ultrasound/MRI data for a complete mapping of tumour development and microenvironment.

  2. Parotid Gland Imaging.

    PubMed

    Prasad, Ravi S

    2016-04-01

    In this article, various imaging modalities are discussed for evaluation of parotid disease, from congenital to inflammatory to neoplastic etiologies. Key imaging characteristics are outlined using case examples. Introduction to biological imaging is highlighted. Additionally, image-guided biopsy techniques are illustrated for sampling parotid and parapharyngeal space lesions in a minimally invasive manner.

  3. Astronomy in the Cloud: Using MapReduce for Image Co-Addition

    NASA Astrophysics Data System (ADS)

    Wiley, K.; Connolly, A.; Gardner, J.; Krughoff, S.; Balazinska, M.; Howe, B.; Kwon, Y.; Bu, Y.

    2011-03-01

    In the coming decade, astronomical surveys of the sky will generate tens of terabytes of images and detect hundreds of millions of sources every night. The study of these sources will involve computation challenges such as anomaly detection and classification and moving-object tracking. Since such studies benefit from the highest-quality data, methods such as image co-addition, i.e., astrometric registration followed by per-pixel summation, will be a critical preprocessing step prior to scientific investigation. With a requirement that these images be analyzed on a nightly basis to identify moving sources such as potentially hazardous asteroids or transient objects such as supernovae, these data streams present many computational challenges. Given the quantity of data involved, the computational load of these problems can only be addressed by distributing the workload over a large number of nodes. However, the high data throughput demanded by these applications may present scalability challenges for certain storage architectures. One scalable data-processing method that has emerged in recent years is MapReduce, and in this article we focus on its popular open-source implementation called Hadoop. In the Hadoop framework, the data are partitioned among storage attached directly to worker nodes, and the processing workload is scheduled in parallel on the nodes that contain the required input data. A further motivation for using Hadoop is that it allows us to exploit cloud computing resources: i.e., platforms where Hadoop is offered as a service. We report on our experience of implementing a scalable image-processing pipeline for the SDSS imaging database using Hadoop. This multiterabyte imaging data set provides a good testbed for algorithm development, since its scope and structure approximate future surveys. First, we describe MapReduce and how we adapted image co-addition to the MapReduce framework. Then we describe a number of optimizations to our basic approach

  4. Features of the Frequency- and Time-Domain Photoacoustic Modalities

    NASA Astrophysics Data System (ADS)

    Lashkari, B.; Mandelis, A.

    2013-09-01

    This article presents an instrumentation and modality-based study of the salient differences between pulsed and frequency-domain photoacoustic (PA) signals with respect to signal processing and imaging properties. The parameters of both modalities were adjusted to achieve the maximum signal-to-noise ratio (SNR). Experiments were performed by employing a dual-mode PA system and under the condition of maximum permissible exposure for both modalities. In addition, proper filtering has been applied post-processing to enhance the image quality for both methods. Theoretical estimates versus practical issues are discussed. In conclusion, it has been shown that parameters of these two methods can be adjusted to provide a competitive SNR and resolution.

  5. 99mTc-Labeled Iron Oxide Nanoparticles for Dual-Contrast (T1/T2) Magnetic Resonance and Dual-Modality Imaging of Tumor Angiogenesis.

    PubMed

    Xue, Sihan; Zhang, Chunfu; Yang, Yi; Zhang, Lu; Cheng, Dengfeng; Zhang, Jianping; Shi, Hongcheng; Zhang, Yingjian

    2015-06-01

    Multi functional probes possessing magnetic resonance imaging and single-photon emission computed tomography properties are favorable for the molecular imaging of cancers. In this study, ultra small super paramagnetic iron oxide nanoparticles, about 3.5 nm in size, were synthesized by the polyol method. The particles were functionalized using c(RGDyC) peptides and labeled with 99mTc to prepare molecular imaging probes for detecting tumor angiogenesis. The probes demonstrated good T1 (r1 = 8.2 s(-1) mM(-1)) and reasonable T2 contrast effects (r2 = 20.1 s(-1) mM(-1)) and could specifically target avβ3-positive cells, inducing more cell ingestion, unlike that in case of the control probes [functionalized with scrambled c(RADyC) peptides]. After the probes were injected into the mice bearing H1299 lung tumors, T1/T2-weighted magnetic resonance imaging and single-photon emission computed tomography revealed that they addressed tumor angiogenic vessels, which were distributed mainly in the peripheral region of tumors. Biodistribution studies indicated that tumor accumulation of the probes was significant [13.8 ± 9.6%ID/g (p < 0.01), which is more than that of the control probes, 4.5 ± 1.9%ID/g], and could be inhibited by free RGD peptides (6.0 ± 2.8%ID/g, p < 0.01). Our study demonstrated that the dual-contrast (T1/T2) magnetic resonance and dual-modal imaging probe based on ultra small superparamagnetic iron oxide nanoparticles is very promising for the molecular imaging of tumor angiogenesis.

  6. Cross-Modality Validation of Acetabular Surface Models Using 3-D Ultrasound Versus Magnetic Resonance Imaging in Normal and Dysplastic Infant Hips.

    PubMed

    Diederichs, Chad; Heath, Alana; Hareendranathan, Abhilash R; Zonoobi, Dornoosh; Kuntze, Gregor; Dulai, Sukhdeep; Mabee, Myles G; Ronsky, Janet L; Jaremko, Jacob L

    2016-09-01

    Current imaging diagnosis of developmental dysplasia of the hip (DDH) in infancy relies on 2-D ultrasound (US), which is highly operator-dependent. 3-D US offers more complete, and potentially more reliable, imaging of infant hip geometry. We sought to validate the fidelity of acetabular surface models obtained by 3-D US against those obtained concurrently by magnetic resonance imaging (MRI). 3-D US and MRI scans were performed on the same d in 20 infants with normal to severely dysplastic hips (mean age, 57 d; range 13-181 d). 3-D US was performed by two observers using a Philips VL13-5 probe. Coronal 3-D multi-echo data image combination (MEDIC) magnetic resonance (MR) images (1-mm slice thickness) were obtained, usually without sedation, in a 1.5 T Siemens unit. Acetabular surface models were generated for 40 hips from 3-D US and MRI using semi-automated tracing software, separately by three observers. For each hip, the 3-D US and MRI models were co-registered to overlap as closely as possible using Amira software, and the root mean square (RMS) distances between points on the models were computed. 3-D US scans took 3.2 s each. Inter-modality variability was visually minimal. Mean RMS distance between corresponding points on the acetabular surface at 3-D US and MRI was 0.4 ± 0.3 mm, with 95% confidence interval <1 mm. Mean RMS errors for inter-observer and intra-observer comparisons were significantly less for 3-D US than for MRI, while inter-scan and inter-modality comparisons showed no significant difference. Acetabular geometry was reproduced by 3-D US surface models within 1 mm of the corresponding 3-D MRI surface model, and the 3-D US models were more reliable. This validates the fidelity of 3-D US modeling and encourages future use of 3-D US in assessing infant acetabulum anatomy, which may be useful to detect and monitor treatment of hip dysplasia.

  7. Brain Structure and Function Associated with a History of Sport Concussion: A Multi-Modal Magnetic Resonance Imaging Study.

    PubMed

    Churchill, Nathan; Hutchison, Michael; Richards, Doug; Leung, General; Graham, Simon; Schweizer, Tom A

    2017-02-15

    There is growing concern about the potential long-term consequences of sport concussion for young, currently active athletes. However, there remains limited information about brain abnormalities associated with a history of concussion and how they relate to clinical factors. In this study, advanced MRI was used to comprehensively describe abnormalities in brain structure and function associated with a history of sport concussion. Forty-three athletes (21 male, 22 female) were recruited from interuniversity teams at the beginning of the season, including 21 with a history of concussion and 22 without prior concussion; both groups also contained a balanced sample of contact and noncontact sports. Multi-modal MRI was used to evaluate abnormalities in brain structure and function. Athletes with a history of concussion showed frontal decreases in brain volume and blood flow. However, they also demonstrated increased posterior cortical volume and elevated markers of white matter microstructure. A greater number of prior concussions was associated with more extensive decreases in cerebral blood flow and insular volume, whereas recovery time from most recent concussion was correlated with reduced frontotemporal volume. White matter showed limited correlations with clinical factors, predominantly in the anterior corona radiata. This study provides the first evidence of the long-term effects of concussion on gray matter volume, blood flow, and white matter microstructure within a single athlete cohort. This was examined for a mixture of male and female athletes in both contact and noncontact sports, demonstrating the relevance of these findings for the overall sporting community.

  8. Multi-modal magnetic resonance imaging and histology of vascular function in xenografts using macromolecular contrast agent hyperbranched polyglycerol (HPG-GdF).

    PubMed

    Baker, Jennifer H E; McPhee, Kelly C; Moosvi, Firas; Saatchi, Katayoun; Häfeli, Urs O; Minchinton, Andrew I; Reinsberg, Stefan A

    2016-01-01

    Macromolecular gadolinium (Gd)-based contrast agents are in development as blood pool markers for MRI. HPG-GdF is a 583 kDa hyperbranched polyglycerol doubly tagged with Gd and Alexa 647 nm dye, making it both MR and histologically visible. In this study we examined the location of HPG-GdF in whole-tumor xenograft sections matched to in vivo DCE-MR images of both HPG-GdF and Gadovist. Despite its large size, we have shown that HPG-GdF extravasates from some tumor vessels and accumulates over time, but does not distribute beyond a few cell diameters from vessels. Fractional plasma volume (fPV) and apparent permeability-surface area product (aPS) parameters were derived from the MR concentration-time curves of HPG-GdF. Non-viable necrotic tumor tissue was excluded from the analysis by applying a novel bolus arrival time (BAT) algorithm to all voxels. aPS derived from HPG-GdF was the only MR parameter to identify a difference in vascular function between HCT116 and HT29 colorectal tumors. This study is the first to relate low and high molecular weight contrast agents with matched whole-tumor histological sections. These detailed comparisons identified tumor regions that appear distinct from each other using the HPG-GdF biomarkers related to perfusion and vessel leakiness, while Gadovist-imaged parameter measures in the same regions were unable to detect variation in vascular function. We have established HPG-GdF as a biocompatible multi-modal high molecular weight contrast agent with application for examining vascular function in both MR and histological modalities.

  9. Optomap ultrawide field imaging identifies additional retinal abnormalities in patients with diabetic retinopathy

    PubMed Central

    Price, Liam D; Au, Stephanie; Chong, N Victor

    2015-01-01

    Purpose To compare diabetic retinopathy (DR) severity grading between Optomap ultrawide field scanning laser ophthalmoscope (UWFSLO) 200° images and an Early Treatment Diabetic Retinopathy Study (ETDRS) seven-standard field view. Methods Optomap UWFSLO images (total: 266) were retrospectively selected for evidence of DR from a database of eye clinic attendees. The Optomap UWFSLO images were graded for DR severity by two masked assessors. An ETDRS seven-field mask was overlaid on the Optomap UWFSLO images, and the DR grade was assessed for the region inside the mask. Any interassessor discrepancies were adjudicated by a senior retinal specialist. Kappa agreement levels were used for statistical analysis. Results Fifty images (19%) (P<0.001) were assigned a higher DR level in the Optomap UWFSLO view compared to the ETDRS seven-field view, which resulted in 40 images (15%) (P<0.001) receiving a higher DR severity grade. DR severity grades in the ETDRS seven-field view compared with the Optomap UWFSLO view were identical in 85% (226) of the images and within one severity level in 100% (266) of the images. Agreement between the two views was substantial: unweighted κ was 0.74±0.04 (95% confidence interval: 0.67–0.81) and weighted κ was 0.80±0.03 (95% confidence interval: 0.74–0.86). Conclusion Compared to the ETDRS seven-field view, a significant minority of patients are diagnosed with more severe DR when using the Optomap UWFSLO view. The clinical significance of additional peripheral lesions requires evaluation in future prospective studies using large cohorts. PMID:25848202

  10. Two-modality γ detection of blood volume by camera imaging and nonimaging stethoscope for kinetic studies of cardiovascular control in nuclear medicine

    NASA Astrophysics Data System (ADS)

    Eclancher, Bernard; Chambron, Jacques; Dumitresco, Barbu; Karman, Miklos; Pszota, Agnes; Simon, Atilla; Didon-Poncelet, Anna; Demangeat, Jean

    2002-04-01

    The quantification of rapid hemodynamic reactions to wide and slow breathing movements has been performed, by two modalities (gamma) -left ventriculography of 99mTc-labeled blood volume, in anterior oblique incidence on standing and even exercising healthy volunteers and cardiac patients. A highly sensitive stethoscope delivered whole (gamma) -counts acquired at 30 msec intervals in a square field of view including the left ventricle, in a one dimensional low resolution imaging mode for beat to beat analysis. A planar 2D (gamma) -camera imaging of the same cardiac area was then performed without cardiac gating for alternate acquisitions during deep inspiration and deep expiration, completed by a 3D MRI assessment of the stethoscope detection field. Young healthy volunteers displayed wide variations of diastolic times and stroke volumes, as a result of enhanced baroreflex control, together with +/- 16% variations of the stethoscope's background blood volume counts. Any of the components of these responses were shifted, abolished or even inverted as a result of either obesity, hypertension, aging or cardiac pathologies. The assessment of breathing control of the cardiovascular system by the beat to beat (gamma) -ventriculography combined with nuclear 2D and 3D MRI imaging is a kinetic method allowing the detection of functional anomalies in still ambulatory patients.

  11. A Robust and Accurate Two-Step Auto-Labeling Conditional Iterative Closest Points (TACICP) Algorithm for Three-Dimensional Multi-Modal Carotid Image Registration

    PubMed Central

    Guo, Hengkai; Wang, Guijin; Huang, Lingyun; Hu, Yuxin; Yuan, Chun; Li, Rui; Zhao, Xihai

    2016-01-01

    Atherosclerosis is among the leading causes of death and disability. Combining information from multi-modal vascular images is an effective and efficient way to diagnose and monitor atherosclerosis, in which image registration is a key technique. In this paper a feature-based registration algorithm, Two-step Auto-labeling Conditional Iterative Closed Points (TACICP) algorithm, is proposed to align three-dimensional carotid image datasets from ultrasound (US) and magnetic resonance (MR). Based on 2D segmented contours, a coarse-to-fine strategy is employed with two steps: rigid initialization step and non-rigid refinement step. Conditional Iterative Closest Points (CICP) algorithm is given in rigid initialization step to obtain the robust rigid transformation and label configurations. Then the labels and CICP algorithm with non-rigid thin-plate-spline (TPS) transformation model is introduced to solve non-rigid carotid deformation between different body positions. The results demonstrate that proposed TACICP algorithm has achieved an average registration error of less than 0.2mm with no failure case, which is superior to the state-of-the-art feature-based methods. PMID:26881433

  12. A Robust and Accurate Two-Step Auto-Labeling Conditional Iterative Closest Points (TACICP) Algorithm for Three-Dimensional Multi-Modal Carotid Image Registration.

    PubMed

    Guo, Hengkai; Wang, Guijin; Huang, Lingyun; Hu, Yuxin; Yuan, Chun; Li, Rui; Zhao, Xihai

    2016-01-01

    Atherosclerosis is among the leading causes of death and disability. Combining information from multi-modal vascular images is an effective and efficient way to diagnose and monitor atherosclerosis, in which image registration is a key technique. In this paper a feature-based registration algorithm, Two-step Auto-labeling Conditional Iterative Closed Points (TACICP) algorithm, is proposed to align three-dimensional carotid image datasets from ultrasound (US) and magnetic resonance (MR). Based on 2D segmented contours, a coarse-to-fine strategy is employed with two steps: rigid initialization step and non-rigid refinement step. Conditional Iterative Closest Points (CICP) algorithm is given in rigid initialization step to obtain the robust rigid transformation and label configurations. Then the labels and CICP algorithm with non-rigid thin-plate-spline (TPS) transformation model is introduced to solve non-rigid carotid deformation between different body positions. The results demonstrate that proposed TACICP algorithm has achieved an average registration error of less than 0.2mm with no failure case, which is superior to the state-of-the-art feature-based methods.

  13. Simulation of the expected performance of INSERT: A new multi-modality SPECT/MRI system for preclinical and clinical imaging

    NASA Astrophysics Data System (ADS)

    Busca, P.; Fiorini, C.; Butt, A. D.; Occhipinti, M.; Peloso, R.; Quaglia, R.; Schembari, F.; Trigilio, P.; Nemeth, G.; Major, P.; Erlandsson, K.; Hutton, B. F.

    2014-01-01

    A new multi-modality imaging tool is under development in the framework of the INSERT (INtegrated SPECT/MRI for Enhanced Stratification in Radio-chemo Therapy) project, supported by the European Community. The final goal is to develop a custom SPECT apparatus, that can be used as an insert for commercially available MRI systems such as 3 T MRI with 59 cm bore diameter. INSERT is expected to offer more effective and earlier diagnosis with potentially better outcome in survival for the treatment of brain tumors, primarily glioma. Two SPECT prototypes will be developed, one dedicated to preclinical imaging, the second one dedicated to clinical imaging. The basic building block of the SPECT detector ring is a small 5 cm×5 cm gamma camera, based on the well-established Anger architecture with a continuous scintillator readout by an array of silicon photodetectors. Silicon Drift Detectors (SDDs) and Silicon PhotoMultipliers (SiPM) are being considered as possible scintillator readout, considering that the detector choice plays a predominant role for the final performance of the system, such as energy and spatial resolution, as well as the useful field of view of the camera. Both solutions are therefore under study to evaluate their performances in terms of field of view (FOV), spatial and energy resolution. Preliminary simulations for both the preclinical and clinical systems have been carried out to evaluate resolution and sensitivity.

  14. Fluoroscopic-guided radiofrequency ablation of the basivertebral nerve: application and analysis with multiple imaging modalities in an ovine model (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Bergeron, Jeffrey A.; Eskey, Cliff J.; Attawia, Mohammed; Patel, Samit J.; Ryan, Thomas P.; Pellegrino, Richard; Sutton, Jeffrey; Crombie, John; Paul, B. T.; Hoopes, P. J.

    2005-04-01

    Pathologic involvement of the basivertebral nerve, an intraosseous vertebral nerve found in humans and most mammalian species, may play a role in some forms of back pain. This study was designed to assess the feasibility and effects of the percutaneous delivery of radiofrequency (RF) energy to thermally ablate the basivertebral nerve in the lumbar vertebrae of mature sheep. Using fluoroscopic guidance, a RF bipolar device was placed and a thermal dose delivered to lumbar vertebral bodies in sheep. Post-treatment assessment included multiple magnetic resonance imaging (MRI) techniques and computed tomography (CT). These data were analyzed and correlated to histopathology and morphometry findings to describe the cellular and boney structural changes resulting from the treatment. Imaging modalities MRI and CT can be implemented to non-invasively describe treatment region and volume, marrow cellular effects, and bone density alterations immediately following RF treatment and during convalescence. Such imaging can be utilized to assess treatment effects and refine the thermal dose to vertebral body volume ratio used in treatment planning. This information will be used to improve the therapeutic ratio and develop a treatment protocol for human applications.

  15. Dual-modal magnetic resonance and fluorescence imaging of atherosclerotic plaques in vivo using VCAM-1 targeted tobacco mosaic virus.

    PubMed

    Bruckman, Michael A; Jiang, Kai; Simpson, Emily J; Randolph, Lauren N; Luyt, Leonard G; Yu, Xin; Steinmetz, Nicole F

    2014-03-12

    The underlying cause of major cardiovascular events, such as myocardial infarctions and strokes, is atherosclerosis. For accurate diagnosis of this inflammatory disease, molecular imaging is required. Toward this goal, we sought to develop a nanoparticle-based, high aspect ratio, molecularly targeted magnetic resonance (MR) imaging contrast agent. Specifically, we engineered the plant viral nanoparticle platform tobacco mosaic virus (TMV) to target vascular cell adhesion molecule (VCAM)-1, which is highly expressed on activated endothelial cells at atherosclerotic plaques. To achieve dual optical and MR imaging in an atherosclerotic ApoE(-/-) mouse model, TMV was modified to carry near-infrared dyes and chelated Gd ions. Our results indicate molecular targeting of atherosclerotic plaques. On the basis of the multivalency and multifunctionality, the targeted TMV-based MR probe increased the detection limit significantly; the injected dose of Gd ions could be further reduced 400x compared to the suggested clinical use, demonstrating the utility of targeted nanoparticle cargo delivery.

  16. Wavelength-Modulated Differential Photoacoustic (WM-DPA) imaging: a high dynamic range modality towards noninvasive diagnosis of cancer

    NASA Astrophysics Data System (ADS)

    Dovlo, Edem; Lashkari, Bahman; Choi, Sung soo Sean; Mandelis, Andreas

    2016-03-01

    This study explores wavelength-modulated differential photo-acoustic (WM-DPA) imaging for non-invasive early cancer detection via sensitive characterization of functional information such as hemoglobin oxygenation (sO2) levels. Well-known benchmarks of tumor formation such as angiogenesis and hypoxia can be addressed this way. While most conventional photo-acoustic imaging has almost entirely employed high-power pulsed lasers, frequency-domain photo-acoustic radar (FD-PAR) has seen significant development as an alternative technique. It employs a continuous wave laser source intensity-modulated and driven by frequency-swept waveforms. WM-DPA imaging utilizes chirp modulated laser beams at two distinct wavelengths for which absorption differences between oxy- and deoxygenated hemoglobin are minimum (isosbestic point, 805 nm) and maximum (680 nm) to simultaneously generate two signals detected using a standard commercial array transducer as well as a single-element transducer that scans the sample. Signal processing is performed using Lab View and Matlab software developed in-house. Minute changes in total hemoglobin concentration (tHb) and oxygenation levels are detectable using this method since background absorption is suppressed due to the out-of-phase modulation of the laser sources while the difference between the two signals is amplified, thus allowing pre-malignant tumors to become identifiable. By regulating the signal amplitude ratio and phase shift the system can be tuned to applications like cancer screening, sO2 quantification and hypoxia monitoring in stroke patients. Experimental results presented demonstrate WM-DPA imaging of sheep blood phantoms in comparison to single-wavelength FD-PAR imaging. Future work includes the functional PA imaging of small animals in vivo.

  17. Terahertz imaging and tomography as efficient instruments for testing polymer additive manufacturing objects.

    PubMed

    Perraud, J B; Obaton, A F; Bou-Sleiman, J; Recur, B; Balacey, H; Darracq, F; Guillet, J P; Mounaix, P

    2016-05-01

    Additive manufacturing (AM) technology is not only used to make 3D objects but also for rapid prototyping. In industry and laboratories, quality controls for these objects are necessary though difficult to implement compared to classical methods of fabrication because the layer-by-layer printing allows for very complex object manufacturing that is unachievable with standard tools. Furthermore, AM can induce unknown or unexpected defects. Consequently, we demonstrate terahertz (THz) imaging as an innovative method for 2D inspection of polymer materials. Moreover, THz tomography may be considered as an alternative to x-ray tomography and cheaper 3D imaging for routine control. This paper proposes an experimental study of 3D polymer objects obtained by additive manufacturing techniques. This approach allows us to characterize defects and to control dimensions by volumetric measurements on 3D data reconstructed by tomography.

  18. Thermal imaging for assessment of electron-beam freeform fabrication (EBF3) additive manufacturing deposits

    NASA Astrophysics Data System (ADS)

    Zalameda, Joseph N.; Burke, Eric R.; Hafley, Robert A.; Taminger, Karen M.; Domack, Christopher S.; Brewer, Amy; Martin, Richard E.

    2013-05-01

    Additive manufacturing is a rapidly growing field where 3-dimensional parts can be produced layer by layer. NASA's electron beam freeform fabrication (EBF3) technology is being evaluated to manufacture metallic parts in a space environment. The benefits of EBF3 technology are weight savings to support space missions, rapid prototyping in a zero gravity environment, and improved vehicle readiness. The EBF3 system is composed of 3 main components: electron beam gun, multi-axis position system, and metallic wire feeder. The electron beam is used to melt the wire and the multi-axis positioning system is used to build the part layer by layer. To insure a quality deposit, a near infrared (NIR) camera is used to image the melt pool and solidification areas. This paper describes the calibration and application of a NIR camera for temperature measurement. In addition, image processing techniques are presented for deposit assessment metrics.

  19. Advanced contrast modalities for X-ray radiology: Phase-contrast and dark-field imaging using a grating interferometer.

    PubMed

    Bech, Martin; Jensen, Torben H; Bunk, Oliver; Donath, Tilman; David, Christian; Weitkamp, Timm; Le Duc, Geraldine; Bravin, Alberto; Cloetens, Peter; Pfeiffer, Franz

    2010-01-01

    Here we review our recent progress in the field of X-ray dark-field and phase-contrast imaging using a grating interferometer. We describe the basic imaging principles of grating-based phase-contrast and dark-field radiography and present some exemplary results obtained for simple test objects and biological specimens. Furthermore, we discuss how phase-contrast and dark-field radiography can be combined with the concept of computed tomography, and yield highly detailed three-dimensional insights into biomedical sample. Exemplary results obtained with standard X-ray tube sources and highly brilliant synchrotron sources are presented.

  20. Dual-modality image guided high intensity focused ultrasound device design for prostate cancer: A numerical study

    NASA Astrophysics Data System (ADS)

    Hobson, Dexter; Curiel, Laura; Chapelon, Jean-Yves; Pichardo, Samuel

    2012-10-01

    In this study the feasibility of designing a multi-element prostate cancer treatment device using Magnetic Resonance Imaging and ultrasound imaging for guidance was determined. A parametric study was performed to determine the optimal focal length (L), operating frequency (f), element size (a) and central hole radius for lodging an imaging probe (r) of a device that would safely treat cancerous tissue within the prostate. Images from the Visible Human Project were used to determine simulated organ sizes and treatment locations. Elliptical tumors were placed throughout the simulated prostate and their lateral and axial limits were selected as test locations. Using Tesla C1060 (NVIDIA, Santa Clara, CA, USA) graphics processors, the Bio-Heat Transfer Equation was implemented to calculate the heating produced during the simulated treatment. L, f a and r were varied from 45 to 75mm, 2.25 to 3.00MHz, 1.5 to 8 times λ and 9 to 11mm, respectively. Results indicated that a device of 761 elements with a combination of L, f a and r of 68mm, 2.75MHz, 2.05λ and 9mm, respectively, could safely ablate tumors within the prostate and spare the surrounding organs.

  1. Clinically-translated silica nanoparticles as dual-modality cancer-targeted probes for image-guided surgery and interventions

    PubMed Central

    Phillips, Evan; Montero, Pablo H.; Cheal, Sarah M.; Stambuk, Hilda; Durack, Jeremy C.; Sofocleous, Constantinos T.; Meester, Richard J. C.; Wiesner, Ulrich; Patel, Snehal

    2015-01-01

    Early diagnosis and treatment of melanoma are essential to minimizing morbidity and mortality. The presence of lymph node metastases is a vital prognostic predictor, and accurate identification by imaging has important implications for disease staging, prognosis, and clinical outcome. Sentinel lymph node (SLN) mapping procedures are limited by a lack of intraoperative visualization tools that can aid accurate determination of disease spread and delineate nodes from adjacent critical neural and vascular structures. Newer methods for circumventing these issues can exploit a variety of imaging tools, including biocompatible particle-based platforms coupled with portable device technologies for use with image-guided surgical and interventional procedures. We describe herein a clinically-translated, integrin-targeting platform for use with both PET and optical imaging that meets a number of key design criteria for improving SLN tissue localization and retention, target-to-background ratios, and clearance from the site of injection and the body. The use of such agents for selectively probing critical cancer targets may elucidate important insights into cellular and molecular processes that govern metastatic disease spread. Coupled with portable, real-time optical camera systems, we show that pre-operative PET imaging findings for mapping metastatic disease in clinically-relevant larger-animal models can be readily translated into the intraoperative setting for direct visualization of the draining tumor lymphatics and fluorescent SLN/s with histologic correlation. The specificity of this platform, relative to the standard-of-care radiotracer, 18F-FDG, for potentially discriminating metastatic disease from inflammatory processes is also discussed in the setting of surgically-based or interventionally-driven therapies. PMID:23138852

  2. Imaging and Molecular Markers for Patients with Lung Cancer: Approaches with Molecular Targets, Complementary/Innovative Treatment, and Therapeutic Modalities

    DTIC Science & Technology

    2011-02-01

    as an official Department of the Army position, policy or decision unless so designated by other documentation. REPORT DOCUMENTATION PAGE Form...aim was completed as reported in the previous annual report. Aim 3 To design tools for molecular imaging of lung tumors. Summary of Research...Findings This project involves a clinical trial that is designed to evaluate the biological activity of RAD001 in patients with early stage non

  3. IMPACT (Imaging and Molecular Markers for Patients with Lung Cancer: Approaches with Molecular Targets and Complementary, Innovative and Therapeutic Modalities)

    DTIC Science & Technology

    2009-03-01

    or in combination with each other or with chemo and /or radiotherapy • To explore applications of molecular imaging for targeted therapy and...kinase) with/without radiotherapy for stage III NSCLC to improve the therapeutic ratio (i.e., increase malignant cell cytotoxicity without increasing...radiation therapy); 2) compliance, which is defined to be completion of concurrent chemoradiation and erlotinib/ radiotherapy with no more than minor

  4. Newer Imaging Modalities to Assist With Target Localization in the Radiation Treatment of Prostate Cancer and Possible Lymph Node Metastases

    SciTech Connect

    John, Subhash S. Zietman, Anthony L.; Shipley, William U.; Harisinghani, Mukesh G.

    2008-05-01

    Precise localization of prostate cancer and the drainage lymph nodes is mandatory to define an accurate clinical target volume for conformal radiotherapy. Better target definition and delineation on a daily basis is surely important in quality assurance for fractionated radiation therapy. This article reviews the evidence for major emerging techniques that show promise in better identifying the clinical target volume. Partial prostate boost by brachytherapy, intensity-modulated radiation therapy, or protons has become possible not only with standard imaging techniques but also with the availability of metabolic images obtained by magnetic resonance spectroscopy. Even though fluorine-18 fluorodeoxyglucose ({sup 18}F-FDG) positron emission tomography has not been found to be useful, novel radiolabeled tracers may eventually prove of value in the diagnosis and treatment planning of prostate cancer. For the metastatic lymph nodes, lymphotropic nanoparticle-enhanced magnetic resonance imaging using ultra-small superparamagnetic iron oxide particles has greater accuracy as compared with conventional techniques and has been instrumental in delineating the lymphatic drainage of the prostate gland. These novel investigational techniques could further help in optimizing conformal radiotherapy for patients with prostate cancer. The concepts of biologic target volume, real target volume, and multidimensional conformal radiotherapy are being explored.

  5. Newer imaging modalities to assist with target localization in the radiation treatment of prostate cancer and possible lymph node metastases.

    PubMed

    John, Subhash S; Zietman, Anthony L; Shipley, William U; Harisinghani, Mukesh G

    2008-01-01

    Precise localization of prostate cancer and the drainage lymph nodes is mandatory to define an accurate clinical target volume for conformal radiotherapy. Better target definition and delineation on a daily basis is surely important in quality assurance for fractionated radiation therapy. This article reviews the evidence for major emerging techniques that show promise in better identifying the clinical target volume. Partial prostate boost by brachytherapy, intensity-modulated radiation therapy, or protons has become possible not only with standard imaging techniques but also with the availability of metabolic images obtained by magnetic resonance spectroscopy. Even though fluorine-18 fluorodeoxyglucose ((18)F-FDG) positron emission tomography has not been found to be useful, novel radiolabeled tracers may eventually prove of value in the diagnosis and treatment planning of prostate cancer. For the metastatic lymph nodes, lymphotropic nanoparticle-enhanced magnetic resonance imaging using ultra-small superparamagnetic iron oxide particles has greater accuracy as compared with conventional techniques and has been instrumental in delineating the lymphatic drainage of the prostate gland. These novel investigational techniques could further help in optimizing conformal radiotherapy for patients with prostate cancer. The concepts of biologic target volume, real target volume, and multidimensional conformal radiotherapy are being explored.

  6. Upconverting nanoparticles: a versatile platform for wide-field two-photon microscopy and multi-modal in vivo imaging.

    PubMed

    Park, Yong Il; Lee, Kang Taek; Suh, Yung Doug; Hyeon, Taeghwan

    2015-03-21

    Lanthanide-doped upconverting nanoparticles (UCNPs) have recently attracted enormous attention in the field of biological imaging owing to their unique optical properties: (1) efficient upconversion photoluminescence, which is intense enough to be detected at the single-particle level with a (nonscanning) wide-field microscope setup equipped with a continuous wave (CW) near-infrared (NIR) laser (980 nm), and (2) resistance to photoblinking and photobleaching. Moreover, the use of NIR excitation minimizes adverse photoinduced effects such as cellular photodamage and the autofluorescence background. Finally, the cytotoxicity of UCNPs is much lower than that of other nanoparticle systems. All these advantages can be exploited simultaneously without any conflicts, which enables the establishment of a novel UCNP-based platform for wide-field two-photon microscopy. UCNPs are also useful for multimodal in vivo imaging because simple variations in the composition of the lattice atoms and dopant ions integrated into the particles can be easily implemented, yielding various distinct biomedical activities relevant to magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography (PET). These multiple functions embedded in a single type of UCNPs play a crucial role in precise disease diagnosis. The application of UCNPs is extended to therapeutic fields such as photodynamic and photothermal cancer therapies through advanced surface conjugation schemes.

  7. Lanthanide-based nanocrystals as dual-modal probes for SPECT and X-ray CT imaging.

    PubMed

    Wu, Yongquan; Sun, Yun; Zhu, Xingjun; Liu, Qian; Cao, Tianye; Peng, Juanjuan; Yang, Yang; Feng, Wei; Li, Fuyou

    2014-05-01

    Applications of lanthanide-based nanoparticles for bioimaging have attracted increasing attention. Herein, small size PEG-EuOF:(153)Sm nanocrystals (∼5 nm) (PEG = poly(ethylene glycol)bis(carboxymethyl)ether) combined with the radioactive and X-ray absorption properties were synthesized. The distribution of the PEG-EuOF nanocrystals in living animals was studied by ex vivo radioassay, inductively coupled plasma-atomic emission spectrum (ICP-AES) analysis and in vivo SPECT imaging, which indicated that the small size PEG-EuOF:(153)Sm had long blood retention time (blood half-life (t1/2) reach to 4.65 h) and were eliminated significantly through biliary/gastrointestinal pathway in vivo. Meanwhile, benefiting from the high attenuation ability of Eu, the small size PEG-EuOF was successfully applied for lymph node CT imaging, extending the bio-applications of these small nanocrystals. The results of cytotoxicity and in vivo toxicity also showed that the PEG-EuOF nanocrystals have relatively low toxicity, which suggest their safety for in vivo imaging. The studies provide preliminary validation for the use of PEG-EuOF nanocrystals for in vivo bioimaging applications.

  8. Modal Mineralogy of Lunar Soils

    NASA Astrophysics Data System (ADS)

    Taylor, J.; Martel, L.; Lucey, P. G.; Crites, S. T.; Blake, D. F.

    2012-12-01

    Modal mineralogy of the lunar regolith is fundamentally important. It varies with the composition of underlying bedrock, extent of addition of materials excavated by impact both local and distant, and small-scale reworking by micrometeorite bombardment, so it contains information about local geological history. Determining modal mineralogy of soils provides vital ground truth to remote sensing studies. Mineralogy can be determined by a variety of techniques that provide complementary information: X-Ray Diffraction (XRD), optical point counting, element mapping by scanning electron microscopy (SEM) or electron microprobe (EMP), and normative calculation from a bulk chemical analysis. SEM and EMP element mapping can be converted into mineral modal abundances in a variety of ways, including defining compositional windows for specific minerals and using image processing techniques. XRD provides direct determination of the phases present, but gives little information about the chemical composition of those phases. We have launched a project to determine the modal mineralogy of over 100 lunar soils from all Apollo sites. The goal is to use this quantitative mineralogy and laboratory and remote reflectance spectra of the same soils to improve our ability to extract quantitative mineralogy from remote sensing data. Samples (< 1mm bulk soils) were dry-sieved and the <150 micron fractions analyzed in a Terra XRD instrument (InXitu, Inc.) using sample sizes of ~35 mg. We reduced the data using Reitveld refinement as implemented by the Jade program (Materials Data, Inc.). Glass abundances were determined by choosing a linear background and fitting a broad Gaussian to the scattering hump above background. Quantitative XRD is well established, but usually requires some calibration, in spite of the sophisticated Reitveld refinement and whole-pattern fitting. We calibrated the instrument by using mixtures of terrestrial minerals and results from the Lunar Sample Characterization

  9. Designing and testing the coronagraphic Modal Wavefront Sensor: a fast non-common path error sensor for high-contrast imaging

    NASA Astrophysics Data System (ADS)

    Wilby, M. J.; Keller, C. U.; Haffert, S.; Korkiakoski, V.; Snik, F.; Pietrow, A. G. M.

    2016-07-01

    Non-Common Path Errors (NCPEs) are the dominant factor limiting the performance of current astronomical high-contrast imaging instruments. If uncorrected, the resulting quasi-static speckle noise floor limits coronagraph performance to a raw contrast of typically 10-4, a value which does not improve with increasing integration time. The coronagraphic Modal Wavefront Sensor (cMWS) is a hybrid phase optic which uses holographic PSF copies to supply focal-plane wavefront sensing information directly from the science camera, whilst maintaining a bias-free coronagraphic PSF. This concept has already been successfully implemented on-sky at the William Herschel Telescope (WHT), La Palma, demonstrating both real-time wavefront sensing capability and successful extraction of slowly varying wavefront errors under a dominant and rapidly changing atmospheric speckle foreground. In this work we present an overview of the development of the cMWS and recent first light results obtained using the Leiden EXoplanet Instrument (LEXI), a high-contrast imager and high-dispersion spectrograph pathfinder instrument for the WHT.

  10. Aluminium hydroxide stabilised MnFe2O4 and Fe3O4 nanoparticles as dual-modality contrasts agent for MRI and PET imaging.

    PubMed

    Cui, Xianjin; Belo, Salome; Krüger, Dirk; Yan, Yong; de Rosales, Rafael T M; Jauregui-Osoro, Maite; Ye, Haitao; Su, Shi; Mathe, Domokos; Kovács, Noémi; Horváth, Ildikó; Semjeni, Mariann; Sunassee, Kavitha; Szigeti, Krisztian; Green, Mark A; Blower, Philip J

    2014-07-01

    Magnetic nanoparticles (NPs) MnFe2O4 and Fe3O4 were stabilised by depositing an Al(OH)3 layer via a hydrolysis process. The particles displayed excellent colloidal stability in water and a high affinity to [(18)F]-fluoride and bisphosphonate groups. A high radiolabeling efficiency, 97% for (18)F-fluoride and 100% for (64)Cu-bisphosphonate conjugate, was achieved by simply incubating NPs with radioactivity solution at room temperature for 5 min. The properties of particles were strongly dependant on the thickness and hardness of the Al(OH)3 layer which could in turn be controlled by the hydrolysis method. The application of these Al(OH)3 coated magnetic NPs in molecular imaging has been further explored. The results demonstrated that these NPs are potential candidates as dual modal probes for MR and PET. In vivo PET imaging showed a slow release of (18)F from NPs, but no sign of efflux of (64)Cu.

  11. Use Of Clinical Decision Analysis In Predicting The Efficacy Of Newer Radiological Imaging Modalities: Radioscintigraphy Versus Single Photon Transverse Section Emission Computed Tomography

    NASA Astrophysics Data System (ADS)

    Prince, John R.

    1982-12-01

    Sensitivity, specificity, and predictive accuracy have been shown to be useful measures of the clinical efficacy of diagnostic tests and can be used to predict the potential improvement in diagnostic certitude resulting from the introduction of a competing technology. This communication demonstrates how the informal use of clinical decision analysis may guide health planners in the allocation of resources, purchasing decisions, and implementation of high technology. For didactic purposes the focus is on a comparison between conventional planar radioscintigraphy (RS) and single photon transverse section emission conputed tomography (SPECT). For example, positive predictive accuracy (PPA) for brain RS in a specialist hospital with a 50% disease prevalance is about 95%. SPECT should increase this predicted accuracy to 96%. In a primary care hospital with only a 15% disease prevalance the PPA is only 77% and SPECT may increase this accuracy to about 79%. Similar calculations based on published data show that marginal improvements are expected with SPECT in the liver. It is concluded that: a) The decision to purchase a high technology imaging modality such as SPECT for clinical purposes should be analyzed on an individual organ system and institutional basis. High technology may be justified in specialist hospitals but not necessarily in primary care hospitals. This is more dependent on disease prevalance than procedure volume; b) It is questionable whether SPECT imaging will be competitive with standard RS procedures. Research should concentrate on the development of different medical applications.

  12. White matter pathway supporting phonological encoding in speech production: a multi-modal imaging study of brain damage patients.

    PubMed

    Han, Zaizhu; Ma, Yujun; Gong, Gaolang; Huang, Ruiwang; Song, Luping; Bi, Yanchao

    2016-01-01

    In speech production, an important step before motor programming is the retrieval and encoding of the phonological elements of target words. It has been proposed that phonological encoding is supported by multiple regions in the left frontal, temporal and parietal regions and their underlying white matter, especially the left arcuate fasciculus (AF) or superior longitudinal fasciculus (SLF). It is unclear, however, whether the effects of AF/SLF are indeed related to phonological encoding for output and whether there are other white matter tracts that also contribute to this process. We comprehensively investigated the anatomical connectivity supporting phonological encoding in production by studying the relationship between the integrity of all major white matter tracts across the entire brain and phonological encoding deficits in a group of 69 patients with brain damage. The integrity of each white matter tract was measured both by the percentage of damaged voxels (structural imaging) and the mean fractional anisotropy value (diffusion tensor imaging). The phonological encoding deficits were assessed by various measures in two oral production tasks that involve phonological encoding: the percentage of nonword (phonological) errors in oral picture naming and the accuracy of word reading aloud with word comprehension ability regressed out. We found that the integrity of the left SLF in both the structural and diffusion tensor imaging measures consistently predicted the severity of phonological encoding impairment in the two phonological production tasks. Such effects of the left SLF on phonological production remained significant when a range of potential confounding factors were considered through partial correlation, including total lesion volume, demographic factors, lesions on phonological-relevant grey matter regions, or effects originating from the phonological perception or semantic processes. Our results therefore conclusively demonstrate the central role of

  13. Cone Beam CT vs. Fan Beam CT: A Comparison of Image Quality and Dose Delivered Between Two Differing CT Imaging Modalities

    PubMed Central

    Weidlich, Georg A.

    2016-01-01

    A comparison of image quality and dose delivered between two differing computed tomography (CT) imaging modalities—fan beam and cone beam—was performed. A literature review of quantitative analyses for various image quality aspects such as uniformity, signal-to-noise ratio, artifact presence, spatial resolution, modulation transfer function (MTF), and low contrast resolution was generated. With these aspects quantified, cone beam computed tomography (CBCT) shows a superior spatial resolution to that of fan beam, while fan beam shows a greater ability to produce clear and anatomically correct images with better soft tissue differentiation. The results indicate that fan beam CT produces superior images to that of on-board imaging (OBI) cone beam CT systems, while providing a considerably less dose to the patient. PMID:27752404

  14. Color reproductivity improvement with additional virtual color filters for WRGB image sensor

    NASA Astrophysics Data System (ADS)

    Kawada, Shun; Kuroda, Rihito; Sugawa, Shigetoshi

    2013-02-01

    We have developed a high accuracy color reproduction method based on an estimated spectral reflectance of objects using additional virtual color filters for a wide dynamic range WRGB color filter CMOS image sensor. The four virtual color filters are created by multiplying the spectral sensitivity of White pixel by gauss functions which have different central wave length and standard deviation, and the virtual sensor outputs of those virtual filters are estimated from the four real output signals of the WRGB image sensor. The accuracy of color reproduction was evaluated with a Macbeth Color Checker (MCC), and the averaged value of the color difference ΔEab of 24 colors was 1.88 with our approach.

  15. Target detection in active polarization images perturbed with additive noise and illumination nonuniformity.

    PubMed

    Bénière, Arnaud; Goudail, François; Dolfi, Daniel; Alouini, Mehdi

    2009-07-01

    Active imaging systems that illuminate a scene with polarized light and acquire two images in two orthogonal polarizations yield information about the intensity contrast and the orthogonal state contrast (OSC) in the scene. Both contrasts are relevant for target detection. However, in real systems, the illumination is often spatially or temporally nonuniform. This creates artificial intensity contrasts that can lead to false alarms. We derive generalized likelihood ratio test (GLRT) detectors, for which intensity information is taken into account or not and determine the relevant expressions of the contrast in these two situations. These results are used to determine in which cases considering intensity information in addition to polarimetric information is relevant or not.

  16. Variation in Additional Breast Imaging Orders and Impact on Surgical Wait Times at a Comprehensive Cancer Center

    PubMed Central

    Golshan, Mehra; Losk, Katya; Mallory, Melissa A.; Camuso, Kristen; Troyan, Susan; Lin, Nancy U.; Kadish, Sarah; Bunnell, Craig A.

    2015-01-01

    Background In the multidisciplinary care model, breast imagers frequently provide second opinion reviews of imaging studies performed at outside institutions. However, the need for additional imaging and timeliness of obtaining these studies has yet to be established. We sought to evaluate the frequency of additional imaging orders by breast surgeons and to evaluate the impact of this supplementary imaging on timeliness of surgery. Methods We identified 2,489 consecutive women with breast cancer who underwent first definitive surgery (FDS) at our comprehensive cancer center between 2011 and 2013. The number of breast-specific imaging studies performed for each patient between initial consultation and FDS was obtained. Chi-squared tests were used to quantify the proportion of patients undergoing additional imaging by surgeon. Interval time between initial consultation and additional imaging and/or biopsy was calculated. The delay of additional imaging on time to FDS was assessed by t-test. Results Of 2,489 patients, 615 (24.7%) had at least one additional breast-specific imaging study performed between initial consultation and FDS, with 222 patients undergoing additional biopsies (8.9%). The proportion of patients receiving imaging tests by breast surgeon ranged from 15% to 39% (p<0.0001). Patients receiving additional imaging had statistically longer wait times to FDS for BCT (21.4 to 28.5 days, p<0.0001). Conclusions Substantial variability exists in the utilization of additional breast-specific imaging and in the timeliness of obtaining these tests among breast surgeons. Further research is warranted to assess the sources and impact of this variation on patient care, cost and outcomes. PMID:26307233

  17. Dual-modal upconversion fluorescent/X-ray imaging using ligand-free hexagonal phase NaLuF4:Gd/Yb/Er nanorods for blood vessel visualization.

    PubMed

    Zeng, Songjun; Wang, Haibo; Lu, Wei; Yi, Zhigao; Rao, Ling; Liu, Hongrong; Hao, Jianhua

    2014-03-01

    Visualization of blood vessel of lung can improve the detection of the lung and pulmonary vascular diseases. However, research on visualization of blood vessel of lung using the new generation upconversion nanoprobes is still scarce. Herein, high quality hexagonal phase NaLuF4:Gd/Yb/Er nanorods were synthesized by a simple hydrothermal method through doping Gd(3+). Doping Gd can not only promote the phase transformation from cubic to hexagonal and the shape evolution from microtube to rod-like, but also provide an additional magnetic properties for biomedical application. The as-prepared nanorods were further converted to water solubility by treating with HCl for eliminating the capped oleic acid. The ligand-free nanorods were successfully used for high-contrast upconversion fluorescent bioimaging of HeLa cells. Moreover, the in vivo synergistic upconversion fluorescent and X-ray imaging of nude mice were demonstrated by subcutaneously and intravenously administrated the ligand-free nanorods. The X-ray signals were matched well with the upconversion signal, indicating the successfully synergistic bioimaging. The ex-vivo X-ray and upconversion fluorescent imaging of various organs revealed that the nanorods were mainly accumulated in liver and lung. More importantly, the blood vessel of the lung can be readily visualized when these ligand-free nanorods are intravenously injected. Apart from the synergistic X-ray and upconversion bioimaging, the ligand-free nanorods can also possess excellent paramagnetic property for potential magnetic resonance imaging contrast agent. Our results have demonstrated the enhanced visualization of blood vessel of lung performed by dual-modal bioimaging of X-ray and upconversion fluorescence, revealing the great promise of these nanoprobes in angiography imaging. Such a new technique enables the integration of the two bioimaging techniques by combining their collective strengths and minimizing their shortcomings.

  18. Future Imaging Alternatives: The Clinical Non-invasive Modalities in Diagnosis of Oral Squamous Cell Carcinoma (OSCC)

    PubMed Central

    Omar, Esam

    2015-01-01

    Background : Oral squamous cell carcinoma (OSCC) has a remarkably high incidence worldwide, and a fairly serious prognosis. This is encouraging further research into advanced technologies for non-invasive methods of making early diagnoses, ideally in primary care settings. Method : In this article, the available objective Non-imaging methods for diagnosing OSCC have been reviewed. MEDLINE, EMBASE, the Cochrane Library, and CINAHL have been searched for advanced technologies of non-invasive methods in diagnosis of OSCC, including oral brush biopsy, optical biopsy, saliva-based oral cancer diagnosis and others. Results : Toluidine blue, one of the oldest non-invasive methods for diagnosing OSCC, is unreliable because of its subjectivity, as it is dependent on the experience of the examiner. The diagnosis of Oral carcinoma by Oral brush biopsy with exfoliative cytology based on nano-bio-chip sensor platform shows 97–100% sensitivity and 86% specificity. Another promising non-invasive technique for OSCC diagnosis is saliva-based oral cancer diagnosis, which is an alternative to serum testing. Optical biopsy, which uses the technology of spectroscopy, can be used to detect changes at a sub-cellular level; thus, it provides information that may not be available with conventional histology with reliable sensitivity and specificity. Conclusion : It is clearly evident that screening and early effective detection of cancer and pre-cancerous lesions have the potential to reduce the morbidity and mortality of this disease. The imaging technologies are subjective procedures since all of them require interpretation and significantly affected by the examiner experience. These make further research for advanced objective procedures. Saliva-based oral cancer diagnosis and optical biopsy are promising objective non-invasive methods for diagnosing OSCC. They are easy to perform clinically at primary care set. They show promising pathways for future development of more effective

  19. SU-E-J-85: The Effect of Different Imaging Modalities On the Delineation of the True Spinal Cord for Spinal Stereotactic Body Radiation Therapy

    SciTech Connect

    Goddard, L; Brodin, P; Mani, K; Lee, A; Garg, M; Tome, W; Kalnicki, S

    2015-06-15

    Purpose: SBRT allows the delivery of high dose radiation treatments to localized tumors while minimizing dose to surrounding tissues. Due to the large doses delivered, accurate contouring of organs at risk is essential. In this study, differences between the true spinal cord as seen using MRI and CT myelogram (CTM) have been assessed in patients with spinal metastases treated using SBRT. Methods: Ten patients were identified that have both a CTM and a MRI. Using rigid registration tools, the MRI was fused to the CTM. The thecal sac and true cord were contoured using each imaging modality. Images were exported and analyzed for similarity by computing the Dice similarity coefficient and the modified Hausdorff distance (greatest distance from a point in one set to the closest point in the other set). Results: The Dice coefficient was calculated for the thecal sac (0.81 ±0.06) and true cord (0.63 ±0.13). These two measures are correlated; however, some points show a low true cord overlap despite a high overlap for the thecal sac. The Hausdorff distance for structure comparisons was also calculated. For thecal sac structures, the average value, 1.6mm (±1.1), indicates good overlap. For true cord comparison, the average value, 0.3mm (±0.16), indicates very good overlap. The minimum Hausdorff distance between the true cord and thecal sac was on average 1.6mm (±0.9) Conclusion: The true cord position as seen in MRI and CTM is fairly constant, although care should be taken as large differences can be seen in individual patients. Avoidning the true cord in spine SBRT is critical, so the ability to visualize the true cord before performing SBRT to the vertebrae is essential. Here, CT myelogram appears an excellent, robust option, that can be obtained the day of treatment planning and is unaffected by uncertainties in image fusion.

  20. Engineering iodine-doped carbon dots as dual-modal probes for fluorescence and X-ray CT imaging.

    PubMed

    Zhang, Miaomiao; Ju, Huixiang; Zhang, Li; Sun, Mingzhong; Zhou, Zhongwei; Dai, Zhenyu; Zhang, Lirong; Gong, Aihua; Wu, Chaoyao; Du, Fengyi

    2015-01-01

    X-ray computed tomography (CT) is the most commonly used imaging technique for noninvasive diagnosis of disease. In order to improve tissue specificity and prevent adverse effects, we report the design and synthesis of iodine-doped carbon dots (I-doped CDs) as efficient CT contrast agents and fluorescence probe by a facile bottom-up hydrothermal carbonization process. The as-prepared I-doped CDs are monodispersed spherical nanoparticles (a diameter of ~2.7 nm) with favorable dispersibility and colloidal stability in water. The aqueous solution of I-doped CDs showed wavelength-dependent excitation and stable photoluminescence similar to traditional carbon quantum dots. Importantly, I-doped CDs displayed superior X-ray attenuation properties in vitro and excellent biocompatibility. After intravenous injection, I-doped CDs were distributed throughout the body and excreted by renal clearance. These findings validated that I-doped CDs with high X-ray attenuation potency and favorable photoluminescence show great promise for biomedical research and disease diagnosis.

  1. Latest developments in the iLids performance standard: from multiple standard camera views to new imaging modalities

    NASA Astrophysics Data System (ADS)

    Sage, K. H.; Nilski, A. J.; Sillett, I. M.

    2009-09-01

    The Imagery Library for Intelligent Detection Systems (iLids) is the UK Government's standard for Video Based Detection Systems (VBDS). The first four iLids scenarios were released in November 2006 and annual evaluations for these four scenarios began in 2007. The Home Office Scientific Development Branch (HOSDB), in partnership with the Centre for the Protection of National Infrastructure (CPNI), has also developed a fifth iLids Scenario; Multiple Camera Tracking (MCT). The fifth scenario data sets were made available in November 2008 to industry, academic and commercial research organizations The imagery contains various staged events of people walking through the camera views. Multiple Camera Tracking Systems (MCTS) are expected to initialise on a specific target and be able to track the target over some or all of the camera views. HOSDB and CPNI are now working on a sixth iLids dataset series. These datasets will cover several technology areas: • Thermal imaging systems • Systems that rely on active IR illumination The aim is to develop libraries that promote the development of systems that are able to demonstrate effective performance in the key application area of people and vehicular detection at a distance. This paper will: • Describe the evaluation process, infrastructure and tools that HOSDB will use to evaluate MCT systems. Building on the success of our previous automated tools for evaluation, HOSDB has developed the MCT evaluation tool CLAYMORE. CLAYMORE is a tool for the real-time evaluation of MCT systems. • Provide an overview of the new sixth scenario aims and objectives, library specifications and timescales for release.

  2. Bio-image warehouse system: concept and implementation of a diagnosis-based data warehouse for advanced imaging modalities in neuroradiology.

    PubMed

    Minati, L; Ghielmetti, F; Ciobanu, V; D'Incerti, L; Maccagnano, C; Bizzi, A; Bruzzone, M G

    2007-03-01

    Advanced neuroimaging techniques, such as functional magnetic resonance imaging (fMRI), chemical shift spectroscopy imaging (CSI), diffusion tensor imaging (DTI), and perfusion-weighted imaging (PWI) create novel challenges in terms of data storage and management: huge amounts of raw data are generated, the results of analysis may depend on the software and settings that have been used, and most often intermediate files are inherently not compliant with the current DICOM (digital imaging and communication in medicine) standard, as they contain multidimensional complex and tensor arrays and various other types of data structures. A software architecture, referred to as Bio-Image Warehouse System (BIWS), which can be used alongside a radiology information system/picture archiving and communication system (RIS/PACS) system to store neuroimaging data for research purposes, is presented. The system architecture is conceived with the purpose of enabling to query by diagnosis according to a predefined two-layered classification taxonomy. The operational impact of the system and the time needed to get acquainted with the web-based interface and with the taxonomy are found to be limited. The development of modules enabling automated creation of statistical templates is proposed.

  3. Three-Dimensional Quantitative Evaluation of the Segmental Functional Reserve in the Cirrhotic Liver Using Multi-Modality Imaging

    PubMed Central

    Xiang, Canhong; Chen, Yingmao; Shao, Mingzhe; Li, Can; Huang, Xin; Gong, Lei; Li, Ang; Duan, Weidong; Zhang, Aiqun; Dong, Jiahong

    2016-01-01

    Abstract To quantitatively evaluate the regional functional reserve in the cirrhotic liver and to seek related index that reflects diminished segmental liver function. A 3D system for quantitative evaluation of the liver was used to fuse technetium-99m galactosyl human serum albumin single-photon emission computed tomography and computed tomography images from 20 patients with cirrhotic liver and hepatocellular carcinoma. A set of parameters reflecting liver function including morphological liver volume, functional liver volume, functional liver density (FLD), and the drug absorption rate constant for hepatic cells (GSA-K) was calculated. Differences in FLD and GSA-K in intrahepatic segments were compared in patients with a tumor embolus (Group Y) and those without such an embolus (Group N) in the right portal vein. Differences in FLD and GSA-K in tumor-bearing (T+ group) and tumor-free (T− group) segments in patients with no tumor embolus (Group N) were also compared. Eleven living donor liver transplantation donor served as the control group. The FLD of the liver as a whole was significantly lower in patients with cirrhosis than in the control group (0.53 ± 0.13 vs 0.68 ± 0.10, P = 0.010). The FLD in segments of the right hemiliver was significantly lower than that in segments of the left hemiliver in Group Y (0.31 ± 0.21 vs 0.58 ± 0.12, P = 0.002) but not in Group N (0.60 ± 0.19 vs 0.55 ± 0.13, P = 0.294). FLD was 0.45 ± 0.17 in the T+ group and 0.60 ± 0.08 in the T− group (P = 0.008). Differences in GSA-K in intrahepatic segments were not significant. In the control group, differences in FLD and GSA-K in intrahepatic segments were not significant. The segmental liver functional reserve can be quantitatively calculated. FLD, but not GSA-K, is an index that reflects diminished regional liver function caused by portal flow obstruction or tumor compression. PMID:26945357

  4. Association between power law coefficients of the anatomical noise power spectrum and lesion detectability in breast imaging modalities

    NASA Astrophysics Data System (ADS)

    Chen, Lin; Abbey, Craig K.; Boone, John M.

    2013-03-01

    Previous research has demonstrated that a parameter extracted from a power function fit to the anatomical noise power spectrum, β, may be predictive of breast mass lesion detectability in x-ray based medical images of the breast. In this investigation, the value of β was compared with a number of other more widely used parameters, in order to determine the relationship between β and these other parameters. This study made use of breast CT data sets, acquired on two breast CT systems developed in our laboratory. A total of 185 breast data sets in 183 women were used, and only the unaffected breast was used (where no lesion was suspected). The anatomical noise power spectrum computed from two-dimensional region of interests (ROIs), was fit to a power function (NPS(f) = α f-β), and the exponent parameter (β) was determined using log/log linear regression. Breast density for each of the volume data sets was characterized in previous work. The breast CT data sets analyzed in this study were part of a previous study which evaluated the receiver operating characteristic (ROC) curve performance using simulated spherical lesions and a pre-whitened matched filter computer observer. This ROC information was used to compute the detectability index as well as the sensitivity at 95% specificity. The fractal dimension was computed from the same ROIs which were used for the assessment of β. The value of β was compared to breast density, detectability index, sensitivity, and fractal dimension, and the slope of these relationships was investigated to assess statistical significance from zero slope. A statistically significant non-zero slope was considered to be a positive association in this investigation. All comparisons between β and breast density, detectability index, sensitivity at 95% specificity, and fractal dimension demonstrated statistically significant association with p < 0.001 in all cases. The value of β was also found to be associated with patient age and

  5. Efficient Dual-Modal NIR-to-NIR Emission of Rare Earth Ions Co-doped Nanocrystals for Biological Fluorescence Imaging.

    PubMed

    Zhou, Jiajia; Shirahata, Naoto; Sun, Hong-Tao; Ghosh, Batu; Ogawara, Makoto; Teng, Yu; Zhou, Shifeng; Sa Chu, Rong Gui; Fujii, Minoru; Qiu, Jianrong

    2013-02-07

    A novel approach has been developed for the realization of efficient near-infrared to near-infrared (NIR-to-NIR) upconversion and down-shifting emission in nanophosphors. The efficient dual-modal NIR-to-NIR emission is realized in a β-NaGdF4/Nd(3+)@NaGdF4/Tm(3+)-Yb(3+) core-shell nanocrystal by careful control of the identity and concentration of the doped rare earth (RE) ion species and by manipulation of the spatial distributions of these RE ions. The photoluminescence results reveal that the emission efficiency increases at least 2-fold when comparing the materials synthesized in this study with those synthesized through traditional approaches. Hence, these core-shell structured nanocrystals with novel excitation and emission behaviors enable us to obtain tissue fluorescence imaging by detecting the upconverted and down-shifted photoluminescence from Tm(3+) and Nd(3+) ions, respectively. The reported approach thus provides a new route for the realization of high-yield emission from RE ion doped nanocrystals, which could prove to be useful for the design of optical materials containing other optically active centers.

  6. Core-shell hybrid upconversion nanoparticles carrying stable nitroxide radicals as potential multifunctional nanoprobes for upconversion luminescence and magnetic resonance dual-modality imaging

    NASA Astrophysics Data System (ADS)

    Chen, Chuan; Kang, Ning; Xu, Ting; Wang, Dong; Ren, Lei; Guo, Xiangqun

    2015-03-01

    Nitroxide radicals, such as 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) and its derivatives, have recently been used as contrast agents for magnetic resonance imaging (MRI) and electron paramagnetic resonance imaging (EPRI). However, their rapid one-electron bioreduction to diamagnetic N-hydroxy species when administered intravenously has limited their use in in vivo applications. In this article, a new approach of silica coating for carrying stable radicals was proposed. A 4-carboxyl-TEMPO nitroxide radical was covalently linked with 3-aminopropyl-trimethoxysilane to produce a silanizing TEMPO radical. Utilizing a facile reaction based on the copolymerization of silanizing TEMPO radicals with tetraethyl orthosilicate in reverse microemulsion, a TEMPO radicals doped SiO2 nanostructure was synthesized and coated on the surface of NaYF4:Yb,Er/NaYF4 upconversion nanoparticles (UCNPs) to generate a novel multifunctional nanoprobe, PEGylated UCNP@TEMPO@SiO2 for upconversion luminescence (UCL) and magnetic resonance dual-modality imaging. The electron spin resonance (ESR) signals generated by the TEMPO@SiO2 show an enhanced reduction resistance property for a period of time of up to 1 h, even in the presence of 5 mM ascorbic acid. The longitudinal relaxivity of PEGylated UCNPs@TEMPO@SiO2 nanocomposites is about 10 times stronger than that for free TEMPO radicals. The core-shell NaYF4:Yb,Er/NaYF4 UCNPs synthesized by this modified user-friendly one-pot solvothermal strategy show a significant enhancement of UCL emission of up to 60 times more than the core NaYF4:Yb,Er. Furthermore, the PEGylated UCNP@TEMPO@SiO2 nanocomposites were further used as multifunctional nanoprobes to explore their performance in the UCL imaging of living cells and T1-weighted MRI in vitro and in vivo.Nitroxide radicals, such as 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) and its derivatives, have recently been used as contrast agents for magnetic resonance imaging (MRI) and electron

  7. Additive controlled synthesis of gold nanorods (GNRs) for two-photon luminescence imaging of cancer cells.

    PubMed

    Zhu, Jing; Yong, Ken-Tye; Roy, Indrajit; Hu, Rui; Ding, Hong; Zhao, Lingling; Swihart, Mark T; He, Guang S; Cui, Yiping; Prasad, Paras N

    2010-07-16

    Gold nanorods (GNRs) with a longitudinal surface plasmon resonance peak that is tunable from 600 to 1100 nm have been fabricated in a cetyl trimethylammoniumbromide (CTAB) micellar medium using hydrochloric acid and silver nitrate as additives to control their shape and size. By manipulating the concentrations of silver nitrate and hydrochloric acid, the aspect ratio of the GNRs was reliably and reproducibly tuned from 2.5 to 8. The GNRs were first coated with polyelectrolyte multilayers and then bioconjugated to transferrin (Tf) to target pancreatic cancer cells. Two-photon imaging excited from the bioconjugated GNRs demonstrated receptor-mediated uptake of the bioconjugates into Panc-1 cells, overexpressing the transferrin receptor (TfR). The bioconjugated GNR formulation exhibited very low toxicity, suggesting that it is biocompatible and potentially suitable for targeted two-photon bioimaging.

  8. Additive white Gaussian noise level estimation in SVD domain for images.

    PubMed

    Liu, Wei; Lin, Weisi

    2013-03-01

    Accurate estimation of Gaussian noise level is of fundamental interest in a wide variety of vision and image processing applications as it is critical to the processing techniques that follow. In this paper, a new effective noise level estimation method is proposed on the basis of the study of singular values of noise-corrupted images. Two novel aspects of this paper address the major challenges in noise estimation: 1) the use of the tail of singular values for noise estimation to alleviate the influence of the signal on the data basis for the noise estimation process and 2) the addition of known noise to estimate the content-dependent parameter, so that the proposed scheme is adaptive to visual signals, thereby enabling a wider application scope of the proposed scheme. The analysis and experiment results demonstrate that the proposed algorithm can reliably infer noise levels and show robust behavior over a wide range of visual content and noise conditions, and that is outperforms relevant existing methods.

  9. Frame modal analysis

    NASA Technical Reports Server (NTRS)

    Guyan, R. J.; Heckenlaible, R. N.

    1971-01-01

    Computer model calculates natural frequencies and modal displacements of three-dimensional frame structures, and generates stiffness and mass matrices. Structures may be divided into several substructures prior to calculation of modal characteristics.

  10. [Imaging modalities of rheumatoid arthritis].

    PubMed

    Tamai, K

    1992-03-01

    Modern diagnostic techniques for rheumatoid arthritis include x-ray examination, arthro- or myelography, CT scan, scintigraphy, thermography, ultrasonography, and MRI. X-ray is the simplest and most common method for assessing the degree of joint destruction. Arthrography provides information on intra-articular pathology. CT is particularly of value in visualizing changes in the axial skeleton. Joint scintigraphy, using 99m-technetium pertechnetate, is available in evaluating the degree of synovial inflammation. Thermography has been performed for a similar purpose. Ultrasound allows a real-time, dynamic study of soft tissues in and around the joint, including tendons, synovium and articular cartilage. MRI most clearly shows various pathological conditions such as pannus, degenerated cartilage or spinal cord compression, although the examination time should be shortened.

  11. In vivo molecular imaging of colorectal cancer using quantum dots targeted to vascular endothelial growth factor receptor 2 and optical coherence tomography/laser-induced fluorescence dual-modality imaging

    NASA Astrophysics Data System (ADS)

    Carbary-Ganz, Jordan L.; Welge, Weston A.; Barton, Jennifer K.; Utzinger, Urs

    2015-09-01

    Optical coherence tomography/laser induced fluorescence (OCT/LIF) dual-modality imaging allows for minimally invasive, nondestructive endoscopic visualization of colorectal cancer in mice. This technology enables simultaneous longitudinal tracking of morphological (OCT) and biochemical (fluorescence) changes as colorectal cancer develops, compared to current methods of colorectal cancer screening in humans that rely on morphological changes alone. We have shown that QDot655 targeted to vascular endothelial growth factor receptor 2 (QD655-VEGFR2) can be applied to the colon of carcinogen-treated mice and provides significantly increased contrast between the diseased and undiseased tissue with high sensitivity and specificity ex vivo. QD655-VEGFR2 was used in a longitudinal in vivo study to investigate the ability to correlate fluorescence signal to tumor development. QD655-VEGFR2 was applied to the colon of azoxymethane (AOM-) or saline-treated control mice in vivo via lavage. OCT/LIF images of the distal colon were taken at five consecutive time points every three weeks after the final AOM injection. Difficulties in fully flushing unbound contrast agent from the colon led to variable background signal; however, a spatial correlation was found between tumors identified in OCT images, and high fluorescence intensity of the QD655 signal, demonstrating the ability to detect VEGFR2 expressing tumors in vivo.

  12. In vivo molecular imaging of colorectal cancer using quantum dots targeted to vascular endothelial growth factor receptor 2 and optical coherence tomography/laser-induced fluorescence dual-modality imaging

    PubMed Central

    Carbary-Ganz, Jordan L.; Welge, Weston A.; Barton, Jennifer K.; Utzinger, Urs

    2015-01-01

    Abstract. Optical coherence tomography/laser induced fluorescence (OCT/LIF) dual-modality imaging allows for minimally invasive, nondestructive endoscopic visualization of colorectal cancer in mice. This technology enables simultaneous longitudinal tracking of morphological (OCT) and biochemical (fluorescence) changes as colorectal cancer develops, compared to current methods of colorectal cancer screening in humans that rely on morphological changes alone. We have shown that QDot655 targeted to vascular endothelial growth factor receptor 2 (QD655-VEGFR2) can be applied to the colon of carcinogen-treated mice and provides significantly increased contrast between the diseased and undiseased tissue with high sensitivity and specificity ex vivo. QD655-VEGFR2 was used in a longitudinal in vivo study to investigate the ability to correlate fluorescence signal to tumor development. QD655-VEGFR2 was applied to the colon of azoxymethane (AOM-) or saline-treated control mice in vivo via lavage. OCT/LIF images of the distal colon were taken at five consecutive time points every three weeks after the final AOM injection. Difficulties in fully flushing unbound contrast agent from the colon led to variable background signal; however, a spatial correlation was found between tumors identified in OCT images, and high fluorescence intensity of the QD655 signal, demonstrating the ability to detect VEGFR2 expressing tumors in vivo. PMID:26397238

  13. Flight simulator with IR and MMW radar image generation capabilities

    NASA Astrophysics Data System (ADS)

    Bonjean, Maxime E.; Lapierre, Fabian D.; Schiefele, Jens; Verly, Jacques G.

    2006-05-01

    In the future, modern airliners will use enhanced-synthesic vision systems (ESVS) to improve aeronautical operations in bad weather conditions. Before ESVS are effectively found aboard airliners, one must develop a multisensor flight simulator capable of synthetizing, in real time, images corresponding to a variety of imaging modalities. We present a real-time simulator called ARIS (Airborne Radar and Infrared Simulator) which is capable of generating two such imaging modalities: a forward-looking infrared (FLIR) and a millimeter-wave radar (MMWR) imaging system. The proposed simulator is modular sothat additional imaging modalities can be added. Example of images generated by the simulator are shown.

  14. Correction of non-additive errors in variational and ensemble data assimilation using image registration

    NASA Astrophysics Data System (ADS)

    Landelius, Tomas; Bojarova, Jelena; Gustafsson, Nils; Lindskog, Magnus

    2013-04-01

    It is hard to forecast the position of localized weather phenomena such as clouds, precipitation, and fronts. Moreover, cloudy areas are important since this is where most of the active weather occurs. Position errors, also known as phase or alignment or displacement errors, can have several causes; timing errors, deficient model physics, inadequate model resolution, etc. Furthermore, position errors have been shown to be non-additive and non-Gaussian, which violates the error model most data assimilation methods rely on. Remote sensing data contain coherent information on the weather development in time and space. By comparing structures in radar or satellite images with the forecast model state it is possible to get information about position errors. We use an image registration (optical flow) method to find a transformation, in terms of a displacement field, that aligns the model state with the corresponding remote sensing data. In particular, we surmise that assimilation of radiances in cloudy areas will benefit from a better aligned first guess. Analysis perturbations should become smaller and be easier to handle by the linearizations in the observation operator. In the variational setting the displacement field is used as a mapping function to obtain a new, better aligned, first guess from the old one by means of interpolation (warping). To reduce the effect of imbalances, the aligned first guess is not used as is. Instead it is used for generation of pseudo observations that are assimilated in a first step to get an aligned and balanced first guess. This step reduces the non-additive errors due to mis-alignment and is followed by a second step with a standard variational assimilation to compensate for the remaining additive errors. In ensemble data assimilation a displacement field is estimated for each ensemble member and is used as a distance measure. In areas where a member has a smaller displacement (smaller position error) than the control it is given

  15. Left ventricular dyssynchrony assessed by two three-dimensional imaging modalities: phase analysis of gated myocardial perfusion SPECT and tri-plane tissue Doppler imaging

    PubMed Central

    Ajmone Marsan, Nina; Henneman, Maureen M.; Chen, Ji; Ypenburg, Claudia; Dibbets, Petra; Ghio, Stefano; Bleeker, Gabe B.; Stokkel, Marcel P.; van der Wall, Ernst E.; Tavazzi, Luigi; Garcia, Ernest V.

    2007-01-01

    Purpose To compare left ventricular (LV) dyssynchrony assessment by phase analysis from gated myocardial perfusion SPECT (GMPS) with LV dyssynchrony assessment by tri-plane tissue Doppler imaging (TDI). Baseline LV dyssynchrony assessed with standard deviation (SD) of time-to-peak systolic velocity of 12 LV segments (Ts-SD) with TDI has proven to be a powerful predictor of response to CRT. Information on LV dyssynchrony can also be provided by GMPS with phase analysis of regional LV maximal count changes throughout the cardiac cycle. Methods Forty heart failure patients, referred for evaluation of potential eligibility for CRT, underwent both 3D echocardiography, with tri-plane TDI, and resting GMPS. From tri-plane TDI, Ts-SD was used as a validated parameter of LV dyssynchrony and compared with different indices (histogram bandwidth, phase SD, histogram skewness and kurtosis) derived from phase analysis of GMPS. Results Histogram bandwidth and phase SD showed good correlation with Ts-SD (r=0.77 and r=0.74, p<0.0001, respectively). Patients with substantial LV dyssynchrony assessed with tri-plane TDI (Ts-SD ≥33 ms) had also significantly higher values of histogram bandwidth and phase SD. Conclusions The results of this study support the use of phase analysis by GMPS to evaluate LV dyssynchrony. Histogram bandwidth and phase SD showed the best correlation with Ts-SD assessed with tri-plane TDI and appeared the most optimal variables for assessment of LV dyssynchrony with GMPS. PMID:17874098

  16. Radiolabeled cyclic arginine-glycine-aspartic (RGD)-conjugated iron oxide nanoparticles as single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) dual-modality agents for imaging of breast cancer

    NASA Astrophysics Data System (ADS)

    Deng, Shengming; Zhang, Wei; Zhang, Bin; Hong, Ruoyu; Chen, Qing; Dong, Jiajia; Chen, Yinyiin; Chen, Zhiqiang; Wu, Yiwei

    2015-01-01

    Ultrasmall superparamagnetic iron oxide nanoparticles (USPIOs) modified with a novel cyclic arginine-glycine-aspartate (RGD) peptide were made and radiolabeled as single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) dual-modality agents for imaging of breast cancer. The probe was tested both in vitro and in vivo to determine its receptor targeting efficacy and feasibility for SPECT and MRI. The radiochemical syntheses of 125I-cRGD-USPIO were accomplished with a radiochemical purity of 96.05 ± 0.33 %. High radiochemical stability was found in fresh human serum and in phosphate-buffered saline. The average hydrodynamic size of 125I-cRGD-USPIO determined by dynamic light scattering was 51.3 nm. Results of in vitro experiments verified the specificity of the radiolabeled nanoparticles to tumor cells. Preliminary biodistribution studies of 125I-radiolabeled cRGD-USPIO in Bcap37-bearing nude mice showed that it had long circulation half-life, high tumor uptake, and high initial blood retention with moderate liver uptake. In vivo tumor targeting and uptake of the radiolabeled nanoparticles in mice model were visualized by SPECT and MRI collected at different time points. Our results strongly indicated that the 125I-cRGD-USPIO could be used as a promising bifunctional radiotracer for early clinical tumor detection with high sensitivity and high spatial resolution by SPECT and MRI.

  17. Fiber-Optic System for Dual-Modality Imaging of Glucose Probes 18F-FDG and 6-NBDG in Atherosclerotic Plaques

    PubMed Central

    Zaman, Raiyan T.; Kosuge, Hisanori; Pratx, Guillem; Carpenter, Colin; Xing, Lei; McConnell, Michael V.

    2014-01-01

    Background Atherosclerosis is a progressive inflammatory condition that underlies coronary artery disease (CAD)–the leading cause of death in the United States. Thus, the ultimate goal of this research is to advance our understanding of human CAD by improving the characterization of metabolically active vulnerable plaques within the coronary arteries using a novel catheter-based imaging system. The aims of this study include (1) developing a